Well, the Spirit of 76, the kind of motto of this crew and the spirit behind the flight has been one of teamwork. We required a lot of teamwork amongst the crew members to execute the difficult portions of this flight, be it the rendezvous, the transfer operations, the EVA, all the spectacular first that took place. But the teamwork didn't end with the crew. It certainly, in fact, had its beginnings as origins with the folks sitting in this room and all the people here at the Johnson Space Center, took a great team, a great team effort to pull off STS-76 and make it look easy. I've had more people come up to me and say, gosh, it looked like you're having a lot of fun up there. The mission was such a great success. Those things don't happen by accident. They happen because of a lot of dedicated hard work that's done by each and every person in this room and the other folks on this center that were associated with making STS-76 a reality. So on behalf of the crew, I'd like to begin today by thanking each and every one of you here. You're all award winners in my mind, and we really appreciate you coming over here today and doing the great work that you do day in and day out at the Johnson Space Center. Well now I'd kind of like to transition into the home movie side of the adventure. I want you to know this is a premiere of this picture. We've looked at edited versions, so I'm as excited as you are to watch what happens here as we roll it. This was the evening before launch, and you can see it. We couldn't ask for better weather. Once the winds calmed down on the 21st, the 22nd turned out to be a spectacular night to go fly with an ungodly hour to lift off at 3.13 in the morning. Here we are walking out of the crew quarters, and I was surprised.  I saw a member of our training team standing there smiling at us. So we had a lot of support from Johnson down there for the launch.  The power of the space shuttle main engines as they throttle up on the pad in those final six seconds, and that feeling in your heart, the bottom of your heart that you know good and well you're going someplace in a hurry here momentarily, is one that will be always a part of my memory. I've never experienced a night launch, and as you can see from the lift off, it's incredibly bright. As we clear the tower, I watched the tower go by. It was like daytime looking out the left window, and during the later stages of Ascent I got to witness post-solid rocket motor separation here. The experience of seeing out the front window of the orbiter pulsating lights from the main engines in the rear. So you are really kind of in a little glow there, a little lighted glow as you proceed uphill toward main engine cutoff eight and a half minutes after lift off. You can see us opening the payload bay doors here, and this is sped up a bit by the way, so it doesn't take so long in the film, but that's always a relief to get on orbit, get a go to stay on orbit and open the doors. The next morning on flight day two after going through the internal airlock and down the tunnel, we got to the hatch for a space hab, and here Ron and I are opening that on our second morning, first real morning on orbit, our second day, to get ready to open up the hab and activate it and start operations back there, and this was a very busy place during the mission. As we float into it here, you can see that there was a lot of stowage back here. There's some new soft stowage bags up on the wall, first time they've ever flown. Those were developed for the other equipment that we had to transfer to mirror. You just saw the gyrodyne on the right side, and this panning view shows the bio rack and the glove box. So between the bio rack and all the transfer operations back here that went on while we were docked, it was a busy place. And back up on the flight deck, Rick is taking a look at the camera mounted up there. That's our electronic camera for kidsat. We left it in the window during the undocked times. It took digitized images of the earth and made them available to the students on the ground who were controlling the camera. This is a view of Florida from kidsat, and I want to emphasize that we really began the rendezvous portion of this mission right from launch as we launched into a lower catch-up orbit on Mir. And as we prepared on flight day two, our particular role in the rendezvous got closer and closer to Mir. But we didn't really get the good video, of course, until we got within a thousand feet or so. This is looking out the ODS centerline up at the Mir as we're approaching from underneath. This is the Mir view, what they saw as they were looking down at the space shuttle Atlantis passing over the earth. We included a couple of views of the crew activities in the flight deck, Chilly at the AF station flying the vehicle, Rich assisting him, and I was bobbing in and out of the field of view there, working the computers and assisting in my particular role. This is a view of the Mir space station as we passed from across the terminator from sun lit portion of the planet to the backside. And it was very interesting to see that with the running lights, Mir was very visible and it was quite bright even on the dark side of the planet. As this process continued of the rendezvous and approach up the R-bar, got closer and closer to Mir. And again, this was sped up too. And part of that intent was to make it flow quicker in the movie, but an added side benefit is it makes the commander look even better because it looks like it's really going fast. But Chilly did a phenomenal job flying the space shuttle up to the Mir. And you can see, this is the end game here. This is where it all comes together. And hitting those critical docking parameters, the target, of course, is shown on the right on the split screen image. We really did get that jostle as we made contact and had the post-contact thrusting firing. And then I must confess to a little bit of relief in the cockpit once we reach that milestone, there Chilly's being congratulated by Rich and it's on to docked activities, Rich. We're giving a panorama of the Mir complex starting with the docking module here. And now you're looking through the aft cockpit. I'll refer back to the target you just saw. We confirmed after we docked that no flyout was required. Thank you, Malice. But it's a beautiful, this thing is, this Mir complex is really large and I have memories of standing back in the ODS, looking up through the tunnel and thinking that it was at least 300 feet up to the Mir complex. Here's a view of the initial hatch opening from the Russian side, of course. And you're going to see a couple of happy faces here between Yuri Aniforanko and Kevin Shilton. Tremendous relief once you get there and you join up and realize that it's an excellent place to be. There's some good work going on up there and felt like home for Shannon already. Neither one of those guys were happy. And of course, Shannon, she felt at home the minute she got there and they put her right to work. She was one of the experts in the transfer activities and it's no small part due to the preparation we had here. And here we're getting ready for the welcoming ceremony, one of the official PAO acts. Due to a small miscoordination, we had the flags in the wrong location. So you're going to see Yuri Ushchev bringing the American flag into the docking module base, or not the docking module, but the base block for the welcome ceremony. And then we're going to pass some gifts that we took up to them. What you'll see is some of the personal items that we gave to our Russian crewmates. They both have a love for children and the future of space exploration. So some of the gifts that we gave them were space books for their children and it brought tears to their eyes. And here you see the gift exchange. Some of the books bought right here in Space Center, Houston. Well, I think I need to pick up here. Right with transporters that you run. I think there's a rich and Rick taking off a docking ring from a gyrodine. We brought up a new one and brought back a used one. We also transferred nearly 1500 pounds of water. This is a byproduct of the shuttle's power system. So we removed iodine from our system and supplied minerals and biocide and then transferred these water bags to the Mir space station. This is going through the shuttle side. There's some empty food containers which we returned to Earth from the Mir station. And finally working our way to the docking module. There's temporary storage in the white mesh bags of food containers containing many of the supplies that will help Shannon and Yuri and Yuri in the coming months. We transferred nearly two tons of science hardware over and nearly one ton back. This is a COUR system used for navigation on the approach and docking for the Russian system that will be brought back and refurbished. We also needed to keep track of the items that went over to Mir and those that were returning back to Earth. So Chilly and I are making sure that we have all of the items in our inventory management system in order. The blue box on the left hand side is a refrigerator freezer in which we brought back urine, blood and saliva samples. The glove box in which Linda is working is where we carried on some of the technology development as well as fundamental biology for a joint effort between the U.S. and several European countries. Here are lintel seeds and the investigation here is for status site polarity. We had several experiments in biology. The middeck is where we had lunch with the Mir 21 crew on dock day. We went over for dinner in the base block of Mir to enjoy Russian food. Each night if we had a chance we sent mail messages by way of a laptop computer and you see Shannon doing just that back to her family. On three separate days we saw the comet. Many of you may have seen it here, Hakataki, in which it was very bright and Rich was the first to notice that and on subsequent days we kept track of the comet. Now the EBA activities. Linda? Well, Ron is helping Rich and I get suited up here in the airlock. We're getting pretty close to getting into our pre-breathed timeline and following that we get ready to go out the hatch. We had a lot of room inside because we had an airlock and a docking adapter and came out of the hatch on the docking adapter. Our first job was to install some clamps on the handrails to deploy the experiment packages later and then our task was to move to a camera to remove it on the docking module and this was used on STS 74 when they docked with Mir and then when they left the docking module there the camera was left there also.  And I took some of the smaller items back and here you see Rich he's translating with the camera itself which is rather large and he was being very careful of that as he shepherded it back to the tunnel adapter where he stowed it temporarily back inside until we were finished with the EBA. Here you see Linda and myself removing one of the four meep containers for installation into the under some clamps on the docking module. We tested out some new tools and equipment for use on the ultimate international space station, the rigid tether and the multiple use tether which we use to transport the the meeps to their work site and install them into the clamps. Here you're going to see one of those activities and then one of the funnest things that Linda and I had to do were the deployment of the meeps and you're going to see that here. It's so much easier to do up there you just give it a little flick and it flies around and I'm sure that this is real time instead of sped up but but tremendously finally designed hardware that worked well in flight and we can learn a lot from the folks at Langley and our own engineering director at here that helped design the hardware for this particular EBA. It all worked well and we deployed this one here is meep number four I believe. The the meep experiments are orbital debris sensors and passive samplers. Well this is my cue for my second come in after really a whirlwind and flurry of activity over several days we were all very very sad to get ready to depart the mere space station. This is the farewell ceremony and I think I can speak for the rest of the crew. Certainly for me it was the most emotion fulfilled moment that I'd had in orbit in two missions. Of course saying goodbye to Shannon there's a chilly given her a hug and wishing her well for her long stay up there until STS 79 goes back to pick her up. On undocked day we again were very busy on that day similarly to the docking day. We prepared configuration wise this orbiter and mere complex to separate and very shortly here we'll see that separation sequence and leading into the fly around. This is chilly waving goodbye to his buddies over there the mere twenty one crew including Shannon. The Russians were very kind to ship down this video which then came from soup to MCC and enabled us to put it in our crew movie in a very timely fashion. Separation here again sped up. We were as I mentioned before very sad to leave and wish we could have stayed longer and been up there with our friends. The separate the initial separation burn a couple of low Z pulses out to get going and. Establish the initial opening rate and as we continue to fly out we assumed a range of four hundred and fifty to five hundred and fifty feet targeted to conduct this fly around of the mirror which I was privileged to fly and it's been for me one of the most professionally rewarding things I've ever done but the same time in the background of my mind also very emotionally charged event. This video will share some of what we saw from on orbit which was just absolutely outstanding and flabbergasting really to see this orbiting complex out our windows and here in this particular case to see video shot from the mirror of America's greatest technology achievement ever a space shuttle in orbit doing what it does best. This is a view of the mere space station over the Great Barrier Reef right after we gave the KU antenna to calm to send TV down this is the first picture that came down to the ground and this particular view is as we mere passes through the horizon approaching the terminator and know it is not a model we saw it with our own eyes and that's what it was and it was outstandingly beautiful with the backlit view and something that I will always treasure in my mind. Now it's coming home time now and Ron did a bang up job shooting these scenes that little camcorder that he holds there is a self shot on the way down starts weighing zero at the start of re-entry and then it starts feeling like it weighs a ton on the way down so he did a great job shooting this. This is out the overhead windows were coming in through the re-entry and you can see the plasma trail behind the orbit there pulsates like that and literally lights the cockpit up and with flashes as you come down out the front window you just get a nice steady pink and orangeish glow as you go through the maximum heating and here we are in a roll reversal one of three that we did as we lined up for our approach at Edwards Air Force Base rather unique long range shot here where you can actually see the RCS jets firing in the tail of the shuttle as we decelerated through around Mach 2 approaching Edwards to keep help keep the nose pointed forward and I logged a night landing on this one because officially the sun hadn't come up but but it sure was a pretty time of day to land it was just the xenons were on but you really didn't need them you could see the ground just find and there wasn't hardly a breath of wind in the air it was real calm smooth skies and it just you know you knew what you were flying the space shuttle was responding just so beautifully it really really flew marvelously and was a joy to bring in for a landing. Rick go ahead and punched out the landing gear force on time and then the drag shoot and the timing was just right on that and cushioned the nose slapped down as as we came rolling down the runway for a stop and I think I'll quote Andy Allen from STS-75 there's there's no better feeling than that call wheel stop particularly when you you know you've done your job you've done the best you can and now it's it's over and it's time to turn turn the vehicle over to the folks at Kennedy to get it ready to start back through the same process all over again to go up and retrieve Shannon STS-79 if I look a little confused here at the end I was doing a nose count and came up one short but but I was assured that that was the right answer so everybody felt terrific after the flight and it was certainly good to get back home to family and friends and you all back here in Houston. We'll ask Rick to go ahead and narrate as they come up so please enjoy them. Thanks Joey of course our crew patched there and I might add Rich's son Brandon who's a seventh grader was largely responsible for the artwork and the concept for this patch and we really appreciate his artistic talents and what he contributed to to make the mission go and to me it's a significant or symbolic in the sense that we not only received great support from Johnson Space Center and every and Kennedy Space Center and everyone that supports the shuttle program but from our families as well and I know speaking for myself I could not have done my part in this mission without this loving support from my home my wife and children so I thank them as well. This is a view as we're approaching the Mir space station again Atlantis in all her orbital glory with the payload bay doors open there just this was one of the few times that I wished I could have stayed on board Mir for a long duration to see what the orbiter looked like in its entirety we were fortunate enough to get some views this is a view that we could see out of one of the living quarter portholes on board the Mir of our spaceship and it's kind of a strange feeling to make that translation across that interface and know that you're in another orbiting vehicle even though you're all tied together and look out the window and see this incredible flying machine out there and this is a view of the Soyuz is up in the upper left hand corner attached to the Kovant one in the baseball and some I think there's some solar arrays down there in the lower left hand corner but we include this particular view because of that beautiful effect you get with that rosy changing to gold and then finally changing to darkness as you pass from the day side of the planet into the night another view for those of you who are geography buffs you probably realized right away that in the field of view kind of in the center right is the Sinai Peninsula one of the things that I found particularly interesting from a photographic point of view is taking pictures of the earth while framing them up and trying to get a good composition with the lines and angles of the solar arrays and the space station itself it really is just as a space shuttle is a beautiful beautiful site on orbit the mirror is really quite striking and beautiful on orbit as well the colors are just incredible once you get up there in the vacuum and clarity of space a view on the fly around that's the northern tip of the south island of New Zealand just to the right of the mirror and of course the deep blue waters of the Pacific as well again a view of mirror at the horizon as we approach the terminator we wanted to wrap up our last few slides just to show the two crews the people that were very fortunate and blessed to be the flight crew members of this particular mission here's the mere 21 crew and of course Shannon is going to be in both of these pictures but we can't say enough good about the opportunities we've had is American astronauts to work with our cosmonaut colleagues in this case Yuri Anna Franco and Yuri Yusicev their professionals in every sense of the word and wonderful guys and just Shannon's gonna have a great time flying with them and working with them in this cooperative venture finally this is the STS 76 crew up until the point we made the official handover of Shannon to the to the mere 21 crew and we'll close with our patch


Welcome to this session on laser beam welding process under the course advanced manufacturing processes. In the last few sessions we have discussed about the solid state welding processes, then the electron beam welding process and plasma arc welding process. We have also seen the working principles, process requirements, advantages, limitations and applications of these processes. Moving on, let us see another advanced welding process, namely the laser beam welding process. We have already discussed about the laser beam machining process in the module 3. So, this laser beam welding process is also similar to that process in the sense that the same kind of laser will be used and here instead of cutting or removing material, we will confine the laser beam power into just melting the materials and fusing the two materials. In the previous lecture, we have discussed about the principles of laser formation, then some unique characteristics of lasers and their applications. However, in this session we will confine our discussion to the welding aspects along with a brief description of the basics and features of and applications of laser beam welding process. The process principles, advantages, limitations and applications of some other important welding processes like force welding and diffusion welding will also be covered in this session. Now, let us move on to first the laser beam welding process. As we have indicated already, this is also a thermal based process in which heat will be generated by the application of laser beam. The coalescence of the surfaces of the material will be produced by heating the work piece due to the impingement of the concentrated beam, laser beam which will be coming out from the laser generating device or we call as laser source. Let us refresh ourselves with the laser system. Although we have already discussed quickly, let us have a recap of the process what we have discussed already. It is a device that produces a concentrated coherent light beam of single frequency by stimulated electronic or molecular transitions to lower energy levels. Laser is an acronym for light amplification by stimulated emission of radiation. If we recall our earlier discussions, we can see that this is for producing laser, one material which is called say, legend, this legend material has to be excited or in other words, the electrons in the orbits of low energy. So, here energy is E 1 and here energy is E 2 which is higher than E 1. Similarly, if we go on to the other orbits, so energy level will be higher subsequently. Therefore, if we apply some or if we supply some energy, this is additional energy to the low energy electrons. So, these are nothing but electrons with different energy levels as we have indicated. Now, if these electrons at relatively lower energy level is shifted to or not to the lower energy level, then up to another level which is at higher energy and this is shifted to further shifted to another level which has got further energy, then they will come to an excited status or excited state which is very very unstable for them to remain for a longer period. Therefore, these electrons will always try to jump to the next lower energy level. They will always keep on trying this. In turn, again they will try to come to their original energy level. While doing so at this moment, when it was here, say they were at this E 3 level. Now, while coming back to E 2 level where E 2 is less than E 3, the difference in the energy del E is nothing but E 3 minus E 2. This energy or delta E is equivalent to h nu and this is nothing but the energy and this energy will be emitted in the form of emitted in the form of some packets or also called as quanta or these are in the form very simple meaning. It can be known as packets of energy. These quantas are also called photons. So, they have single wavelength. Therefore, they are you can say monochromatic monochromatic in nature and these quantas are nothing but what we call as laser. Therefore, while coming back here, they will emit some radiation. This is nothing but h nu. Similarly, while coming out from here, they will emit some radiation. This is nothing but h nu which will be now equivalent to h E 2 minus E 1. Again, it will be delta E. So, this is nothing but what we call as laser. What we call as laser here? So, this is the basic principle how we produce or we can get laser from a lasing material or a lasant that is lasant. So, for this we need an external source of energy that we call as additional source or this we call as excitation energy which will be generally in the form of some additional UV light or some other arrangement and the material in the excited state will emit this laser energy or the photons. These will be allowed to get reflected several times inside the device or inside the lasing device and after it gets amplified to a certain level, then they will be allowed to come out from the device or the lasing environment from the system through special mechanisms and that will be taken away or collected for different applications. So, this is the basic principle of laser production that we will see how they are being manipulated further for different applications. In the laser beam welding process, laser beam is directed by flat optical elements such as mirrors and then focus to a small spot for high power density. At the workpiece where we want to do the welding operation using either reflective elements or some special lenses. This is the schematic of the laser system. This is what just we were discussing just now. It is schematic is on the screen. This is the lasing material I was talking about or also called as lasant. So, here it is shown as a rod which can be say ruby rod if it is a solid state material or neodymium, yttrium, aluminum, garnet rod. So, these are some of the lasing material or lasant solid state lasant. Or from that we can use some gases also like argon system, helium argon system or carbon dioxide is a very popular lasing material. Now, this lasant is being excited by some additional energy. So, this is the energy supply system, additional energy supply system. Generally these are like krypton or xenon flash lamps. So, they pump energy, pump energy in the form of some light waves which will be responsible for causing the population inversion. What is the situation called population inversion? Like just we have discussed just now the electrons from lower energy level to higher energy level will be knocked up. That means that will create a very unusual situation of electron densities at the cells, outer cells where generally the number of electrons will be different from that of inner cells or for that matter we can say each cell has got some fixed number of electrons because owing to its electronic configuration. Now, if we disturb that number which is naturally occurring say for example, in the outer cell if there were 4 electrons. Now, if we knocked up few more electrons on to the outer cell say for example, it has come to 8 then it is called a situation that is population inversion. We have created an abnormal situation of different abnormal population in the outer cell. Now, at this day that as I have already told the electrons are in an unstable condition and they will always try to jump to the near nearer cells or low or low orbits to come to in order to come to the outer cell. They are normal conditions therefore, they will always try to jump down to the next orbits next lower energy level orbits and thereby making the population inversion condition going back to the original condition. However, because of this additional source this population inversion will be kept on creating or will be maintained over a period and therefore, these electrons although they will jump back to the next electron energy next lower energy level cells some more electrons will be again brought back or knocked up to the higher energy level cells. However, this while jumping down to the smaller energy level cells the energy released will be in the form of some photons or we can say in the form of some radiations which will be as shown in the in the figure will be continuously being reflected in this system. This is shown as 100 percent reflector system. So, in between in between the chamber or the enclosure. So, some specially placed mirrors are there which will be responsible for their continuous reflection of these beams and after getting amplified to a certain or required level they will be allowed to come out through this lens or the mirror through this mirror system which is partially reflective. That means some portion of the amplified energy or the beam in the form of laser will be allowed to come out from this system and this amplified energy which is called laser will be used for industrial purposes or for other purposes which can be for say medical purposes as well. It is as we have already seen the schematic or the principle this laser welding device is a non-contact device in which there is no conventional electrode and a work piece contact or the tool work piece contact situation. And therefore, there is no question of applying any pressure as well. Inert gas welding is generally employed to prevent oxidation of the molten puddle and filler metals may be occasionally used as we have already spoken about. This is a thermal based process and causes material to get melted. Therefore, it is prone to oxidation if the environment is not controlled properly. Therefore, some shielding gases for certain materials which are very easily oxidizable, very susceptible to oxidation should be used. Some shielding gases should be used for protecting the weld pull from this oxidizing agents. Now, let us talk about the gas lasers which is generally widely used in case of laser beam welding. And as we have already indicated the carbon dioxide is the most popular gas laser. The electric discharge style of carbon dioxide gas lasers are the most efficient type currently available for high power laser beam material processing. These lasers employ gas mixers primarily containing nitrogen and helium along with a small percentage of carbon dioxide. An electric glow discharge is used to pump this laser medium that is to excite the carbon dioxide molecules. Gas heating produced in this fashion is controlled by continuously flowing the gas mixture through the optical cavity. Thus, carbon dioxide lasers are usually categorized according to the type of gas flow system which they employ.   They are the simplest of the carbon dioxide gas laser family. So, gas flow is maintained in the same direction in this case as the laser operators resonators optical axis. And the electric excitation filled or the gas discharge part in the same direction. These are capable of generating laser beams with a continuous power rating of approximately 800 watts for every meter of discharge length. A folded tube configuration is used for achieving output power levels of 50 to 100 watts maximum. And in case of fast axial flow Faf in short gas lasers. They have a similar arrangement of components as that of the slow axial flow gas lasers. Except that in the case of fast axial flow gas lasers a roof blower or turbo pump is used to circulate the gas at high speed through the discharge region and corresponding heat exchangers. Fast axial flow gas lasers with continuous output power between 500 to 6000 watts are easily available. Then comes the transfers flow gas lasers. These lasers operate by continuously circulating gas across the resonator cavity by means of a high speed fan type blower. While maintaining an electric discharge perpendicular to both the gas flow direction and the laser beams optical axis. Transverse flow lasers with continuous wave output power levels between 1 and 25 kilowatt are easily available. A schematic of this type of flow gas laser is shown here in the screen.  So all the requirements or the components like polarizing mirror, rear mirror all these components are integrated in this system. And this is where this is the device through which we can have the beam output. This gas flow direction etcetera are also being shown in this figure. Now let us look at the advantages, major advantages of laser beam welding process. So this includes the following number one. Heat input is close to the minimum required to fuse the weld metal. Thus heat affected zones are reduced and workpiece distortions are minimized. As we have already spoken about. So this is also another thermal based process and heat affected zones is most likely. However because of the characteristics of laser that it can be just focused to a very narrow zone. Therefore the heating effect to the nearby material of the weld point will be much less. This is clearly an advantage of this process like we have seen in the electron beam welding process also. In that case also the beam can be concentrated to a very small diameter spot. And therefore the heat affected zone nearby to this working zone will be much less. Number two no electrodes are required in this case welding is performed with freedom from electrode contamination, indentation or damage from the high resistance welding currents. In fact there is no current being applied to the workpiece or the system, the system only the laser production system does need the power supply that is different. Laser beam welding being a non-contact process distortions are minimized and tool wears are eliminated. Welding in areas that are not easily accessible with other means of welding can be done by laser beam welding. Since the beams can be focused, aligned and directed by optical elements on a very precise area. This we have spoken about in case of electron beam welding as well. So, even if there is a small constriction, so this laser beam being very very thin in diameter or the diameter of the beam is very less can be guided to a very restricted area as well. And welding can be done in which case perhaps the conventional welding electrodes could not be inserted to reach that particular area. And of course, the conventional welding rods will give a macro level welding spot which can be reduced to a very very narrow or small zone in case of laser welding. Therefore, it is suited mostly for for micro joining or micro manufacturing applications. Laser beam can be focused on a very small area permitting the joining of the small and closely spaced components with tiny welds that is usually ideally it is suited for most of the micro fabrication purposes. Then, wide variety of materials including various combinations can be welded by laser beam welding method. Thin welds done by laser welding or small diameter weirs are less susceptible to burn back effects. This is clearly an advantage. The burn back is quite often noticed in arc welding for small and thin sections which can be easily avoided in case of laser welding system. Materials with dissimilar physical properties such as electric resistance can also be welded very effectively here because electric resistance, electrical resistance does not come into the picture in case of laser beam welding process. And no vacuum or x-ray shielding is required in this case which is clearly an advantage situation. Laser welds are not influenced by magnetic fields as in the case of arc and electron beam welds where magnetic field influences the beam itself and it can deflect the beam from the axial point of focus etcetera. But here in this case it is not so. They also tend to follow weld joints through the root of the work piece even when the beam and the joint are not perfectly aligned. Then the aspect ratios which is nothing but depth to width ratio of the order of 10 is to 1 could be attainable in this laser beam welding process. This process can be automated very easily and controlled by robots also. The process gives very high repeatability which is very important as per as the process performance is concerned. It provides very high accuracy, this provides very high control, accuracy of control is very high and high speed can be obtained. Let us at the same time note few limitations of this process as well. The joints that are obtained by laser beam welding must be accurately positioned laterally under the beam and at a controlled position with respect to the beam focal point. This is very critical for accuracy of the welding process. In case of mechanical clamping of the weld joints it must be ensured that final position of the joint is accurately aligned with the beam impingement point. The maximum joint thickness that can be welded by laser beam is somewhat limited. The weld penetrations of larger than 19 millimeter are difficult to weld. High reflectivity and high thermal conductivity of materials like aluminum and copper can affect the weldability of lasers. This we have of course we have seen in case of laser beam machining as well where it is difficult to machine those materials which has got very high reflectivity particularly that of like copper and aluminum and their alloys. These materials have got very high reflectivity and laser as such does not work very well with this type of materials. An appropriate plasma control device must be employed to ensure the weld reproducibility while performing moderate to high power laser welding. Lasers tend to have a fairly low energy conversion efficiency which is generally less than 10 percent. So, this is a point of concern as far as the economics of the system is concerned or economics of the process is concerned. Some weld porosity and brittleness can be expected as a consequence of the rapid solidification characteristics of the laser beam welding. The rays of laser are harmful to human body and needs precautions. Now let us see few applications of this process. It is being used in the following sectors like in defense applications, aerospace applications, automotive applications, marine applications, medical applications, building constructions, electronics, power generation and networks, alternative energy devices like fuel cells, solar power and wind turbines, nuclear applications, oil and gas industries and then many home appliances. Now let us move to few new trends in laser welding which is transmission or overlap welding. Joining of polymers by lasers is a relatively new area which is achieved using a laser transparent material and laser absorbing material. The schematic is shown in the screen here. So, here as shown in the screen there are two materials that upper material this is transparent to laser. So, laser can penetrate this material and fall on the other material and this material the bottom material is laser absorbing material. Therefore, the material here gets heated up upon this incident of this laser material and therefore, this heated material then gets fused to or gets bonded to the top material because of the application of the light pressure on them and this molten material can get the both the halves bonded. So, this is called laser overlap welding process. The laser beam penetrates in this case the upper material and is absorbed by the lower material thus heating up the lower layer directly that we have seen in the screen in the figure. This layer transports the heat indirectly via heat expansion and conduction to the upper layer. So, that both materials are simultaneously heated up and melted. External pressure can be applied to make them get intimated which can give higher strength to the welded materials which is almost equal to that of the base material. The benefits of such a transmission welding process through laser is that the weld is inside the component. This is very important that is not exposed to the environment or outside we can see anything. The surface is not affected and no micro particles are generated in the joint. The laser beam is absorbed by the lower component and local heating thus take place. Due to conduction of heat the upper component is melted through the application of external pressure solidification of the melt zone occurs yielding a joint. In brief in this laser welding process we have studied the process and the features of the laser beam welding laser applications and new trends in this category. Let us discuss some other welding processes. First of all the force welding process it is one of the oldest known processes to mankind. In this process the ends of the parts to be joined are heated to a temperature slightly below the solidest temperature and the pressure is applied so that a fusion joint is obtained. The process is similar to the traditional method used by blacksmiths. The force can be applied by manual blows continuously or repeatedly by a machine or by rolls. In case of ferrous alloys a thin layer of iron oxide gets formed when the heated metal is exposed to atmospheric oxygen. This oxide layer has to be removed before further weld passes. Flux is applied to that so that the oxide layer becomes more fluid and under pressure flows out to the joint. Borax and silica are sands are used as fluxes. Rot iron and low carbon steels can be easily force welded. It is a slow process and is a more labor intensive process. The quality of this weld depends more on the skill of the welder rather than the process. Hence this is an expensive process and not much in use in industries. Another process is diffusion welding process. Diffusion welding process is also known as diffusion bonding process. The diffusion can be achieved when one keeps two pieces in intimate contact under pressure. The pressure used in the range of 35 to 70 mega Pascal. By using heat the bonding time can be further reduced as the diffusion process gets accelerated through heat. The heat applied is much slower than the melting points of metals. The pressure needs to be kept optimum such that there is no plastic deformation. A complete intimate contact is essential in this process. A filler material can be used and is kept between the two metals to be joined. It aids in the reduction of operating temperature and permits some atmosphere around the joint instead of using a vacuum. In one method the plates are kept together in contact inside the chamber and the plates are heated through normal electric resistance. During heating an inert gas is pumped inside the chamber to provide uniform pressure on the process to be joined. This method is used for joining nonferrous metals since the pressure and temperature are relatively low. In the second method vacuum chamber is used and plates are kept under contact inside it. Force is applied mechanically by means of dead weight or a press. As the pressure applied can be higher it is suitable for welding ferrous metals. The filler material if used its thickness is in the range of 5 to 25 microns only. In such a case it is expected that the temperature required for bonding is reduced by the formation of a eutactic alloy. Thus the filler metal diffuses into the two metal plates and forms a eutactic joint. Diffusion welding can be used for joining metals to metals and metal to non metals as well. Since diffusion welding method is used in joint formation metallurgically the joints are sound without any defects. It produces neat welds requiring no further processing on it unlike many other processes. Now let us summarize what we have studied in this session. We have discussed about the laser beam welding process first. Then briefly we have refreshed how the laser is being produced and different requirements applications and limitations of the laser beam welding process. We have also discussed the force welding process and diffusion welding process. The potential applications of these processes have also been discussed. We hope this session was informative and interesting. Thank you.


Hello my beautiful internet friends this video I am so freaking excited to bring to you guys because I feel like as monumental as this is for me There's so many people who have sent me encouraging messages like out of the blue being like hey I know you're you know process disappointments coming up I hope it goes well, and I hope you get a walk soon So many of you guys are so incredibly invested in this with me that I am so excited to tell you guys about today And let's not waste any more time with words. Let's start with this morning It's 8 a.m. And I might be getting a leg today. It's also October 11th Which is the one-year anniversary of the day that I lost my leg. I'm really trying to control my expectations of today I want to Simultaneously think that like nothing good is gonna happen and also that I'm like gonna walk out of there with a leg today And I don't think either one of those things is gonna happen. I think we'll probably be some forward movement Super anxious. We're gonna get our ceremonial Starbucks coffee for the ride up to Denver Let's do this There's always an answer Joe, right? What you're watching right now is me getting a direct socket This is a totally different process than getting casted for other prosthetics I've actually never seen of it or heard of it before. However, it's pretty darn cool They literally build the socket directly on your leg though. It does come with some Let's just say interesting difficulties, which you'll see in just a moment here, but check this out. This is pretty amazing We should tell you that this is your new leg Of course it did you second everything I Would give it time We are home home and icing this puppy up because walking Walking kind of aggravates it a little bit, but not nearly as much as I thought it would It might actually be happening guys. This may be real Legitimate literal and figurative steps forward. I feel like completely overwhelmed by emotions I've kind of gone from like holy crap. This is amazing to like. Oh my god. Nothing's gonna work Even if it feels good, it's never gonna work like that paralyzing fear to like I'm so grateful that today went well Holy crap today went well and there's no asterisk on there. There's no like oh it went well, but it just went well I have a leg that is home with me. It's freaking awesome. It's so much lighter than the other ones It fits better than the other ones. It looks so much better than the other ones Which is not the most important thing, but it's nice to like how your leg looks. I like how this one looks I am emotionally and physically completely drained at this moment, but I'm happy drained I know that this is like the first step towards Getting to where I actually want to go and I feel like I can see a little bit of that light like everything that I've gone through in the last 365 days might actually be worth it because after so much time I must begin to forget why I did it in the first place because there's been so many issues This is why I did it these moments are the reason that I did it. It's not gonna be easy, but it's so worth it It's here. It's starting and I don't know what tomorrow is gonna bring I don't know if anything is gonna happen. Of course. I'm worried that something's gonna go wrong, but it's going wonderfully It's actually going wonderfully right now and I took steps I even took steps hands-free like holy crap I did not expect to be able to do that and yeah, my legs pretty sore right now But it's not horrible like I'm not in a ton of pain I know like give it a few weeks and I'm gonna be like sobbing with happiness I'm just I feel like there's so much emotion in me right now That I can't I'm only feeling like so much of it, you know, because I'm so overwhelmed and drained I really can't wait to see where this goes and I feel like for the first time in a long time Things are happening the way that I want them to happen and I'm so grateful for that I'm so thankful for that check this out guys. Like it even looks pretty freaking cool.  Thank you to my patrons who helped so much in so many different ways one of which is helping me have the money available to Be able to pay the deductible for things like this leg You guys help me in more ways than you know and by watching this video You are helping me in more ways that you know. Thanks so much guys.  I mean like have some water and maybe a drink and some appetizers Cuz that's my kind of party. I love you guys. I'm thinking of you and I'll see you in the next video


This is stock number 11234. We are here at Summit Automotive in Fond du Lac, Wisconsin. You're new and used heavy-duty truck and ram headquarters today. We are checking out this super clean 2018 ram 2500 crew cab short box This truck has the 6.7 liter Cummins diesel It has been fully safe deed and inspected by our service shop has a fresh oil and filter change all the fluids have been checked and topped off and It is 100% ready to go Brilliant black crystal pearl is the color. We shoot all of our videos in 1080p 60 frames per second So if you have HD capabilities on your computer tablet or smartphone device Turn them on right now because it is definitely your best way to check out the quality and condition of the truck before seeing it in person And if you'd like to check out all the photos on this truck in the upper right hand part of your screen is a link to our website Click that and check us out there. It comes with the 18 inch steel rims with the chrome covers and it has Crosswind AT LT 275 70 R 18 tires and these tires look like they have a really good amount of tread left I'd say 70 to 80% Frame and underbody on this truck is exceptionally clean. This one came out of Colorado and Montana Front fender is in excellent shape. I didn't see any dents or dings on there Headlight lenses are nice and clear and that front bumper is in excellent condition I didn't see any dents or dings on that and the lower valence is in nice shape as well the hood No dents on there looks really good passenger side front fender same story Ram 2500 and Cummins logo look really good and The passenger side rim no scuffs or scrapes on there As you go down this side of the truck take note of how reflective and mirror like that paint is We take these HD videos So if you are far away or even if you're close by and you just cannot make the trip down But you're still interested in purchasing the vehicle You can see the truck hear the truck and have confidence in what you're looking at before you even get here So that when you do get here, there's absolutely no surprises Cab is in a shape and that is why we offer the summit auto fast-pass Option in the upper right hand part of your screen a link right to our website where you can apply for financing get pre-approved See a payment quote even appraise a trade all from the comfort of your own home So when you get here all you got to do is drive the truck love it You'll be all set to go back tires have just as much tried as those front tires and the frame and underbody back here is Exceptionally clean as well And it is like that all the way underneath other than a little bit of dust Has all the remaining factory exhaust, but no corrosion lower rockers all look really good as well Definitely what you want to see On a used truck no corrosion As we come around to the back of the vehicle rear bumper is in excellent shape as well-known denser dings does have a full towing package Which includes a receiver hitch four pin and seven pin wiring and that tailgate is an excellent condition too This is an SLT package Has a nice rugged liner drop-in bed liner That's a nice shape And as you go down the driver's side just as clean as that passenger side No dense or dings on the box And for full disclosure this back rim just as nice as the rest Doors all look really good Does come with the power heated mirrors And if you thought the outside was nice on this truck the inside is equally as nice if not nicer Inside the SLT package gives you the gray cloth interior No rips or tears on those seats Very nice condition. We do have weather tech floor mats in this truck auto headlamps Power windows power locks power mirrors And we'll hop inside check out the miles and everything you can see that this one has 26,055 miles you get an outside temp and compass display instrument cluster is very nice and clean This one does have Bluetooth capabilities Steering wheel is in nice shape cruise controls on the right Bluetooth and information center controls on the left does come with the six-speed automatic transmission with the optional tap shift Turn dial four-wheel drive Keyless entry has the five inch touchscreen radio AM FM and Sirius XM radio capabilities And this is also where your backup camera shows up Down here you have your climate controls factory brake controllers stability control tow-haul and your factory exhaust brake Carpeting and passenger side floor mat are in excellent shape as well and the passenger side seat No rips or tears on there smells very clean inside this truck And the headliner is an excellent condition to You do get map lights up here your power sliding rear window button and Won't check out the back seats and then we'll start it up and check out under the hood But very very clean in the front you get that 40 2040 split bench seat So this is a six-passenger Vehicle back seats are just as clean as the front seats no rips no tears back here It does have the latch child safety system power sliding rear window You do get storage underneath these seats And then you also get in-floor storage on each side With removable containers for easy cleaning you can actually put ice and drinks in there It's like you got too many coolers wherever you go just dump them out and you're all set to go Doors all look really good, and it does have child safety locks on the back doors Of course all the bottoms of the doors and everything looks really good on this truck As well. We'll start it up and take a quick look under the hood I would personally like to thank you for checking out the video today, and hopefully from this HD video You will have been able to tell just how clean this truck is all the way around inside and out Under the hood we have the 6.7 liter Cummins diesel Engine bay is very very clean and it's very smooth Once again this truck has been fully safe and inspected by our service shop as a fresh foil and filter change All the fluids have been checked and topped off The truck has been gone through mechanically 100% And is 100% ready to go The headlights are nice and clear And I would highly recommend this truck to make quality and condition standpoint and to see more pictures of this truck Or one of our other 450 new and used cars trucks SCVs minivans wranglers half tons three quarter tons one tons you name it. We got it website Full pictures and descriptions of every single vehicle from two locations all at summit auto comm and if you'd like to check out more HD videos You can go to youtube comm slash summit auto remember to like subscribe and share on this video and all the videos that you see there In fact in a second we'll see a link to subscribe to a YouTube channel on your left a link to more Ram 2500 truck videos like this and on your right You've not been to our website on the bottom link to this vehicle on our website click those check us out We really look forward to help you with this super clean 2018 Ram 2500 crew cab short box SLT and brilliant black crystal pearl. Thanks again for checking out the video


Hey guys, welcome back to my YouTube channel. This is Daniel Rosel here bringing you this video today from Jerusalem. I've just been out in Jerusalem city center for a few hours with a friend of mine, Marcus James subscriber to this YouTube channel. Also a rookie or aspiring videographer a bit like myself. Marcus said, he said, you know, Daniel Sonny said, you have a great head of hair and you need to have three point, three point lighting. And I said, you're right, Marcus. I need to work on my lighting. So I just spent the last hour. It's now about two in the morning here in Israel, trying without success to get my lighting right because as you can see, there's still the shadow over here. So I want to say firstly to Marcus, thank you. Kidding aside, I appreciate your technical help. I appreciate all the feedback I get from people that helps me to improve this YouTube channel because that's what I really love about YouTube. And what I'm really loving about video is there's such a learning curve. There's always more to do and more to improve. So I don't think I just for reference, I do, I am using three lights in this video, but yeah, it's maybe a little bit better than it was before. Anyway, what I wanted to talk about for this video blog today was Facebook groups that might be useful to you if you are new to Israel. If you have made aliyah now Facebook these days, I'm 33 years old, but it already has a bit of an old person's connotation. A lot of the young kids in the block. I've heard are using TikTok and Instagram and therefore Facebook is thought of as a bit of a sort of platform for people my age and older. It still remains if you're an English speaker moving to Israel, Facebook definitely remains a great conduit of information. And you can also find community. You can make friends through some of these groups moving to Israel. Of course, the number one objective is always to learn Hebrew. And one point I'm not going to do. I'm not going to include Hebrew groups on this particular video, but just to say that for every English group, there is a corresponding Hebrew group, more or less, and not that I have any disrespect for my fellow English speaking immigrants to Israel. To the contrary, I have enormous respect for anyone who picks themselves up from wherever they are in the world to make this exciting journey. But just to say that in general, it's a long standing belief of mine. In fact, I think it's probably pretty on on controversial that you're going to get better, better information if you're searching for stuff in Hebrew. Just got more people and is it is the language here. That was all that was all that out of the way. Let's go check out some of the Facebook groups that are on the better known site for newcomers to Israel. And let's jump over to my computer. Okay, so starting out my my virtual tour with one of the well-known groups here. It's called secret Jerusalem. Now I'm going to post the URLs for these different Facebook groups at the bottom. There's a couple of groups because they're sort of supposed to be anonymous. I'm not going to scroll down into last anyone any participants, you know become visible. So just to protect people's privacy secret Jerusalem is a very useful group. If you are a English speaker specifically living in Jerusalem, there's also a group called secret Tel Aviv and in fact, there's a whole network of groups called secret and start the name of the city. They're secret. Ranana secret elat secret Haifa etc. So if you're if you've moved to a community in Israel with the number of English speakers, you're probably going to find a secret group. Now it's it's called secret. There's nothing really secret about it. I think it started as a kind of underground page for people and now it's just become it's a kind of watering cooler. If you will for English speakers secret Jerusalem clearly intended for Jerusalemites. So therefore it tends to be a bit more right wing and religious than let's say some of these other groups and that's just a reflection of the demographics that are here in Israel. But if you are in Jerusalem, you're new to the city, you're looking for you know common that you just want help from people. You can post in one of these groups and they've just enabled the anonymous posting feature which I think is very useful. So if you have a question and you for whatever reason you don't want it to be visible to your friends on Facebook that you're posting. It does allow you to post anonymously and people requiring help of various kinds whether mental or financial uses functionality. So I think it's great that that's their second group broadening broadening out a little bit from the context of cities is this group called Anglos in Israel and people have mixed feelings about the whole term Anglo. It actually comes from Anglo. It's supposed to be Anglo foe Anglo phone. I think right someone who speaks English is technically called an Anglo phone just as there is Franco phones etc. So it's become an abbreviation. I was very confused when I moved to Israel and people were calling me an Anglo and my brain went straight to Anglo Saxon which was like an ancient people marauding across Europe on these freaky boats. So he's like an Anglo. So that's what an Anglo means. Some people don't like the term. I can't say I love it but it's just used to refer to English speakers in Israel. So that particular group Anglos in Israel is open for English speakers no matter what part of the country they're in and again these groups are just kind of watering coolers exchange of information. What older folks sometimes refer to as list serves right you used to have these things nowadays group of groups is probably the closest approximation and it was an email list and of course nowadays most of this dialogue has moved over to Facebook but Anglos in Israel is a good group and as you can see from the membership number twenty six point nine there are a lot of groups like this they're and they're quite big. There's just a lot of English speakers in Israel. So these are useful just to point out I'm gonna I said I wouldn't show Hebrew groups and I've ended up including one of them in my sort of wrap up here. This one's called Yaro Shalimim that Yaro Shalimi which means Jerusalemites in the male plural and Jerusalemites in the female plural and just to show you guys what a Facebook groups looks like looks like in Hebrew the writings in Hebrew the conversations are in Hebrew and it's this is actually in my opinion a good way to improve your Hebrew especially if you're looking for picking up more kind of slangy Hebrew you might find words used in this group that are more colloquial let's say so this is a big group and if you compare its size to secret Jerusalem this one has one almost one hundred and seventy eight thousand members so that's like a lot of people so if you're living in Jerusalem and you want to dip your toes however gradually into the world of Hebrew groups this is one that I would personally recommend I'm just popping myself up a small bit here now there's a lot of groups also for folks who are making Aliyah and this is something I wish I knew about before I personally moved to Israel back in 2015 I moved to Israel from Cork in Ireland and I was like the only Jewish person really that I knew outside of my immediate family members so I don't really have anyone to talk to and bounce ideas about Aliyah around about maybe talk about is Jerusalem a good community for me are there other alpans that you might recommend I was completely reliant upon the kind of official information I was getting from the Jewish agency I would just personally recommend if you're for whatever reason in this boat you're making Aliyah you're moving to Israel from a place without a Jewish community or maybe you just don't know anyone in your real Jewish community your real world network who has made Aliyah then I really really recommend putting the search terms into Facebook there are groups for folks who are in the over 50s category you know older people making Aliyah there's ones for a specific profession so if you're an accountant considering making Aliyah and you've questions specifically about licensing in Israel there's a real real strong network of these groups there is a couple of communities on reddit and I've talked a lot on this channel about reddit but not really they don't really have communities like this on reddit there's just one for Israel and it tends to be more political discussions something you will see on these Facebook groups is that it tends to often be a no politics rule and that's just because Israel is such a politically controversial place and these groups are really focused on more pragmatic concerns helping folks to make the Aliyah process easier navigate the bureaucracy etc etc just want to also say one more thing before we jump back to the screen here and that's it this is like a very incomplete selection I've tried to pluck out a few groups from the ones I'm a member of just to give a kind of flavor for the different types of groups that are out there on Facebook okay guys let's continue Israeli foodies I'm looking I'm seeing my friend Shemshon Lashinsky up there very because he's become a very popular food reviewer among the English speaking community here I've done a few videos with Shemshon he's a very very funny person and I like Shemshon a lot so if you're looking for a discussing more foodie concerns like ingredients etc where can I find this then Israeli foodies is a good group there's also one specifically for coffee lovers there's one for spicy pepper lovers there's like a lot of groups you name what your interest is in Israel and you know put that together with Israel like Israel coffee and I'm almost guarantee that you will find a group matching that description restaurant club Jerusalem is a group again I'm focusing a little bit more on Jerusalem here because it's where I live but this is a really good group run by I think it's Debest Israel is how it's a pronounced or written this is someone Debbie I think her name is she has a really good website there and she posts links to new restaurants that have opened and gives reviews about them not just in Israel what I like about restaurant club Jerusalem is it's not exclusively for kosher keepers there is one for people who keep kosher and even for among people who keep kosher there's people on different degree some people keep Mahadrin kosher so that can be something that you know if you if you're not really if you're just happy with regular kosher that all might be unnecessary info for you but restaurant club Jerusalem and rest restaurant club Israel are two good groups if you're looking for new places to try out here's another one of the secret groups I mentioned at the start of this video this is called secret talaviv and it definitely eclipses secret Jerusalem and size is 401.6 thousand members at the time I'm recording this video it has like jobs board it has a website this is like a serious operation I think this got closed down at some point by Facebook and then after restart maybe I'm wrong about that but it is secret talaviv and there is as you can see here a secret talaviv dot com there's a jobs board and we're just going to get into jobs presently so this group nephish benefic jobs in Israel just a couple of comments about it for many many years this was kind of kind of recommended as like the go-to forum if you're a new English speaker in Israel and you're looking for employment opportunities not the only one but one of the main groups in that category my personal feeling and observation is that it's gone down in quality over the years now my recommendation maybe I'll do a separate video about job hunting in Israel I particularly recommend linked in you know I'm I've been working in a job for my current job for the past six months but I'm previous rounds of job searching I actually had a lot of success on LinkedIn you can filter now for hybrid jobs remote jobs or in-office jobs depending on what you're looking for and I think that linked in specifically for jobs has become a more vibrant ecosystem than nephish benefic is group but they mean well nephish benefic has a jobs board on their site and if you're looking perhaps to pick up more casual work like working in a kitchen or a hotel you might find this group to be useful here's a great group again living financially smarter in Israel LFS II it's run by someone called Rivka Lebevowitz I hope I'm getting her name right she has some great videos actually on YouTube she interviews other financial English speaking financial professionals in Israel this group is again kind of a wealth of information people discuss here very openly and that's that's something that it took me a while to appreciate about Israel there was a time when I thought I was the only person with kind of questions about life in Israel or struggles in Israel particularly of the financial variety and it's nice even sometimes to just talk with other people openly beyond your close friend circle in the real world about the concerns we share as immigrants in Israel whether that's how we can afford property amongst the crazy property more market how you can qualify for government first-time buyer schemes and stuff like that talking about the pros and cons of different credit cards so if you're looking to get to grips with your your personal finances in Israel really really really recommend strongly this Facebook group a lot of knowledgeable people posting there continuing and I've just got three more groups to go guys and again this is just my sort of cherry picking from the group this one's called LFS II your recommendations LFS II stands for living financially smarter in Israel so it's not just one group it's kind of a network of groups and if you're looking for a specific thing for instance if you're looking to buy a puzzle for your kids or a technical product of some nature and you're looking for sources in Israel this group is often useful for that another group of the same kind of and the same kind of page a little bit it's called live in Israel shop online it's a it's a it's a private group there is a frugal group so for whatever reason living frugally is a big part of your the picture for you as you live in Israel and you're looking for ways to cut down on your bills and save money on foods there there are a couple of group big groups for living frugally in Israel there's also women's only groups and clearly as a guy I'm unfamiliar with exactly what those ones are but just to say they are out there my wife I'm sure knows the names but if you are a woman you'll probably find out about those groups from your from your friends here's a really important group it's called get help Israel and of course I've talked about mental health on this channel a few times and been open about my own journey getting therapy accessing psychiatric help for anxiety and depression get help us get help Israel comms a really terrific resource it's a listing of English speaking mental health practitioners and one thing I've said many times I'm actually going to open up one more page just as I'm doing this because I just realized there's one I should have included in this and I've left out so I'll just kind of be looking off to my screen for a few seconds here but certainly that's a very useful group if if you're looking for help now the health care system in Israel works really well when it comes to mental health care sometimes it's not quite as as it's not the same well-oiled machine as the physical health care system and again I'm not just pining here I'm talking from personal experience but if you are looking for help you're struggling with something like ADHD depression anxiety there is an ADHD specific group just to say but get help Israel is a good group and you can post anonymously there if again if you're looking for a psychiatrist or therapist and you don't want that post being seen by all your Facebook friends I think a really really useful and important feature for for folks one of the newer groups here I like this one it's called achieving financial independence in Israel I think it's run by a guy called Aaron or his friend I was on Aaron's YouTube channel a few weeks ago is a really good guy and he's interviewing folks in Israel pension professionals financial professional tax advisor I'll put a link to Aaron's website his project called it's called alia money tips so if you plug that into Google you should get his web operation and his YouTube from that and this is a good group because I like the fact that it focuses on achieving financial independence because for a lot of us at the start of our journeys in Israel we're just looking to kind of get by and what they call and in Hebrew finish the month and then I think sometimes over the course of many years we can set our ambitions a little bit higher and we actually start thinking about long-term financial planning and so I think these more focus groups for investments and this kind of thing are particularly helpful now wrapping up I did say I skipped one that I should have included and that's this group it's called navigating the Israeli health care system the Yad La'olim health care division and this group is run by the Shira Pransky project which is a really really good resource if you are trying to navigate the Israeli health care system including actually mental health care providers this group is kind of run and operated by them again I'll put the links in the video description here or you can just type it into Facebook I don't see most of these groups go in the way anytime soon and that this is a really good group if you have medical questions you're looking for a practitioner you're looking for a question about if you a specific medication exists in Israel but just to underscore one more time before I wrap up the video that for all of these groups you're going to find comparable groups in Hebrew so if your Hebrew is good enough to be able to type in Hebrew and read post in Hebrew I personally would recommend joining both because you're going to find more groups in Hebrew more specific groups and sometimes also just more up-to-date information so as I see the video is almost 18 minutes long I'm going to wrap this up here if you are new to Israel or you're in the process of making aliyah again there's nothing stopping you from joining these communities before you come here so you can start getting smart about how to live in Israel before the wheels of your airplane hit the tarmac in Ben-Gurion Airport and again speaking from my own aliyah experience I regress not looking for information beyond the officialdom of Nefesh Benefesh and the Jewish Agency not that there's anything wrong with either organization both do a great job but there is really really distinct value in my opinion in more peer-to-peer or Olay to Olay information and I just remembered one more old olim helping you young olim if you're a seasoned veteran of the crazy Israel world and that you have you think you can help folks who are younger on in the journey don't forget to check out that group as well hope this roundup of some Facebook groups that might be useful for you as a new immigrant to Israel has been useful I do post these Israel specific videos to a separate playlist on this YouTube channel called living in Israel I'll also put that link in the description and for everyone watching whether you knew here coming here about to come here best of luck in your aliyah journey remember there's help out there not just not just from the official sources but other folks here in Israel and don't hesitate even though sometimes people can get nasty on Facebook that's for sure don't let it get to you look for information network with your fellow olim a native Israelis of course as well and really good communities to join thank you guys for watching more videos coming soon if I get more of course feel free to also subscribe to this YouTube channel thank you for watching


Now we have Matthias and Sergius to talk about Kubernetes matrix API. All right, thanks. Okay, cool. Hi, I'm Sergius. By the way, can you hear me? Works? Okay, cool, great. I'm Sergius. I'm a software engineer at Red Hat. Traditionally, I come from the Kubernetes ecosystem. All things around that topic. And now I'm working on all things Prometheus inside Kubernetes at Red Hat. Together with Matthias. So, hi, I'm Matthias. I'm a software engineer at Red Hat as well. Do all kinds of, like, go Kubernetes Prometheus as well. And I also organized the Prometheus Berlin meetup. So if you ever happen to be in Berlin, we might as well have a Prometheus meetup. So this is the agenda. While you're reading this, please give a quick hands of who uses Kubernetes. All right, who uses Prometheus? All right, same amount. So you all should be users of basically what we are. We use the Prometheus adapter. Awesome. Okay, so maybe you don't know yet. So yeah, this is the agenda. Quickly going through the history. We don't have much time, so let's get going. So the history of Kubernetes metrics was kind of rough in the beginning. It was simply hard coded into Kubernetes. It started with CPU and memory metrics for each port and node. And this was basically the architecture. So we had Heapster in the middle, and it would go to the Kubelet and see Advisor and get the metrics from there and then put it in some storage backend, which wasn't really, like, decoupled from Heapster. So Heapster had, like, a lot of, like, I don't know, if it's, like, feature creep in a way. So yeah, these are the problems. And it was a push-based model. As I said, it had, like, the vendor dumps, opinionated tooling abstraction, and what about, like, Prometheus, right? So we want to, like, use Prometheus. So where is it? So these were the goals for refactoring this, trying to decouple it and introduce an abstract API schema so that we can actually use Prometheus or maybe something else even if we want to. So meet the metrics APIs inside Kubernetes. We have the resource metrics, which are CPU and memory, so what you're already familiar with and what actually was in Kubernetes right from the beginning. And then we have now custom metrics, which are metrics that you can define to be bound to a Kubernetes object. So for example, to a pod or a deployment to a job, something like that. And then we have external metrics. External metrics are simply something coming from your cloud provider, for example, which are not really tied to anything Prometheus-specific, and we can still leverage those inside of Kubernetes. So this is the architecture. We have the API server at the very top. CubeCity, HPA, which is the horizontal pod autoscaler, and the scheduler will talk to that API. And in our case, we have the Kubernetes Prometheus adapter running, and this will actually, which Sagesh will explain, transform the API calls coming to Kubernetes into something that Prometheus understands so that we can use both together. So there are kind of these example implementations for the metrics APIs, something that is often shipped with Kubernetes, so to say by default, is the metric server, and this has only the resource like CPU and memory metrics implemented, and we are going to take a look at deeper into the Prometheus adapter. As you can see, external metrics are work in progress, but it also has the custom metrics already. So going into detail now. Okay, cool. So resource metrics. As you learned, we have three metrics, hopefully three orthogonal metrics APIs inside Kubernetes, and I just might take a step back here to this slide because I really like that one. The important message of this slide is that Prometheus adapter is not the only provider of custom metrics. You can actually mix and match those implementations. You can use the Prometheus adapter to host your custom metrics, whereas still taking your old metrics server to host resource metrics. Or you could use the Prometheus adapter to host resource metrics inside your cluster, but a totally different adapter hosting custom metrics for your provider at will. And two implementations that we also enlisted here are for Azure and Stackdriver. I'm not sure if there exists one for AWS. We simply didn't find it on Google. That's why it's not in the slide probably. So it's important for you. You can mix and match those things per API group, namely per metrics state, SIO, custom metrics, and Excel metrics. You are not married to the Prometheus adapter at all. So resource metrics, the first API of those three. How do we actually first find out if our cluster is able to support that? There is a API services object inside a Kubernetes, which you can query. And if you ask a Kupka to get API services, metrics, state, SIO, it will tell you if the thing is available or not. And the thing becomes available if you deploy the Prometheus adapter and register it as a so-called API service. Resource metrics have two well-defined metrics. As you learned, one is all about nodes and the other is all about pods. Nodes, metrics are obviously not namespaced. Nodes are ubiquitous across the whole cluster. And pods obviously are deployed on a namespace basis. So those two first class resource objects are available inside Kubernetes. And you can query them the same way you query any other object inside Kubernetes, as you would say, I don't know. Kupka will get deployments. Kupka will get pods or whatnot. You can do Kupka will get pods.metrics.kfsio and it will list all available resource metrics inside your cluster. In this example, we simply enlisted the Grafana resource metrics and you will get an output like this, which should be very familiar for any other Kubernetes object. So now the question is, you know, what you see here is we query resource metrics for Grafana. We get the output, we have two containers. One is named Grafana. The other one is unnamed. One is occupying 10 millis of CPU and some memory. How do these metrics get into there by the help of the Prometheus adapter? Obviously, oh, sorry, before we go to the other slide, this is probably the command that some of you know, the kupka top part under the hood, it does exactly the same what I just did manually with kupka to get metrics for the pods. The configuration for the Prometheus adapter is pretty straightforward. It's a simple little config map inside Kubernetes and it follows a pretty simple structure at least for the resource metrics. And as you can imagine, when you do a kupka top part at the end of the day, there must be some Prometheus query being executed. And that's all what the config map is about. So when you specify this configuration, you can specify rules for retrieving resource metrics. So one is for querying CPU metrics per container and that's essentially like a very simple rate-based query against Prometheus. And the other one specifies the query for executing or for retrieving metrics regarding nodes. As you can see, all of this is totally configurable. When you deploy the Prometheus adapter that is shipped inside the repository, we come with the predefined query for you, but you can all tweak this by yourself and we have a pretty simple go template-based system where all the parameters to instrument that query will be dependency injected for you. So the query is being executed. Some metrics are being retrieved from Prometheus. So how does the connection now go on when you get a metric series back with values and the actual object inside the Kubernetes world? So the other section inside that configuration is called resources. And that's because we want to associate some label names that come back from Prometheus with the Kubernetes resource objects that we are querying against. In the case of resource metrics, these are either nodes or parts. So what you will see here is like a simple map-based representation. This is what I called a roverite configuration. When a label name called node is present inside the metric, we will map it one-to-one to the Kubernetes resource node. And this resource name node comes from the verbs that you are used to when you execute kubectl commands. So we could equally write in there nodes, the polarization form. The Prometheus adapter behind the scenes will normalize this. So for the node and namespace name labels, these map one-in-one with the resource names from Kubernetes. One exception, and I know there is some dangling pull requests out there, at least some effort there to normalize this. And CAdvisor unfortunately exposes metrics regarding parts with the part underscore name label. So we have to map this to the resource type part manually. All of this is also configurable. So if you have some more other label names which sort of do not have a perfect impedance match with the Kubernetes world, you can configure this here via overrides. Another thing, the metrics of obviously you saw we have per container metrics. So you also have to provide the mapping what the label is all about, which specifies container metrics. And that's the last part for resource metrics configuration. I specified this query here as you remember. Container CPU uses seconds total. So one little hint for you to sort of like find out or discover yourself how these metrics look like in the Prometheus server. There is one nifty API call, API v1 series which you can give it a selector and it will give you back like metadata about the metrics series. And question who didn't know this API call before? OK, that's cool. Just remind this yourself this is very nice for debugging and finding out about like the structure of the metrics that are present inside the Prometheus. For instance, you will get back all the label names that come back here. So as you may remember from the previous slide we have the label name, container name which we will associate with the container account. We have the label name, name space pod and pod name which we associated with the corresponding resource names from Kubernetes using the overrides configuration. Same goes for memory. Same principle applies here. As you learned we have CPU and memory metrics for resource metrics. Same stuff, no magic. Instead of having some CPU metric here we are invoking a sum of container memory working set bytes from CAdvisor. And one little bit you have to tell the Prometheus adapter of the window because that's what the Kubernetes also API expects. The window you took the measurements from and these must correspond to the window that you specified in the rate function. So take care that you match those two guys. Custom metrics. Resource metrics has been quite easy but custom metrics are a little bit of a different beast. Resource metrics are predefined in the Kubernetes API. Custom metrics is something that you totally define yourself. So you can invent totally custom metrics and based upon these metrics you can instrument the horizontal pod outer scaler for instance to scale up your parts. So the process here unfortunately is not that easy. Custom metrics API is always as Matthias mentioned bound to a very concrete Kubernetes type or Kubernetes resource, pod services, jobs ingress objects, whatever is present inside inside your cluster. Same thing as above. You find out if custom metrics are enabled by calling get API services view on beta one custom metrics KSIO and see if it's available. Unfortunately since the metrics that come from the custom metrics world are not first class Kubernetes resource types it's not that easy to query them as like kubectl get part stop metrics. Fortunately there is a raw command which lets you explore the Kubernetes API internally and if you do kubectl get raw slash API is custom metrics KSIO it will list you like all the available custom metrics inside your cluster which are out to discovered. In this case what I prepared here for you canonical example, requests per second metric that I configured inside my cluster and you will get a nice representation of this one. So exactly same question as above how does this metric get there? And the Prometheus adapter has like a four step process to accomplish this. First one is it has a method of discovering the metrics inside your Prometheus all configurable and you will learn how to accomplish that. Then second step as before once we found out about our metrics we have to associate them with the Kubernetes resource types then we need to provide some naming of those metrics inside our cluster. These names may vary for instance if you apply the rate function the name HTTP requests per second total doesn't make any sense because the rate function is a per second function or the result of that is a per second value. So you may want to apply the per second suffix to that metric name. So you want to configure that. And finally as before you want some way of configuring the actual query of those custom metrics against Prometheus. Again config mac as before instead of resource you specify the section rules and in order to configure the metrics what you set up here is a so called series query. So in this series query we will be executed against the very same API endpoint of Prometheus that I showed you before and I recommend you to because that's what we've been struggling with right what is the selector what metrics are actually being returned when I configure this beast here when you take this HTTP requests total namespace is not empty and stitch it into this series API discovery endpoint of Prometheus you will get a nice list of metrics that will be fetched from the Prometheus adapter. In this case HTTP requests total and in the selector we specified namespace to be not empty in the hope that these metrics are somehow related to Kubernetes right and it depends upon you to specify those selectors as explicit as possible in order not to have false positive and fetch metrics which don't have to do anything with Kubernetes at all. Second point association and again we have the resources section in the previous example you learned about the so called overrides configuration the second method of configuring this association between label names and resource names is a very simple template so what we did here is we set dot resource and what we simply assume is that the label name equals one in one with the Kubernetes resource name that is present inside your cluster so you have both possibilities to configure those resource associations and you can mix and match both inside this configuration so again example as before and here you will actually see a nice false positive the namespace label name will be associated with namespace objects part with parts, service with service and the job actually is false positive here therefore we very often specify those overrides directly to do these associations because it's not always obvious if all those label names really refer to Kubernetes objects second name naming third thing naming so once you have your metric HTTP request total you probably want to apply a rate function to it so we must change the name that is exposed inside Kubernetes and here we have a very simple regex-based approach and in this case we just simply here group here the prefix underscore total take the group one and append per second so you have quite some flexibility here to do this conversion of names so HTTP request total becomes HTTP request total second final thing once you have everything in place you found out about your metrics you associated them with Kubernetes resource objects and you converted your names you actually want to specify the actual query so in this case we simply have a rate-based theory which we execute against it with again some go-templating mechanism in order to get a very concrete metrics value of custom metrics we don't have such a nice way as with resource metrics you can execute this kubectl get-raw command with the endpoint custom metrics state-sio for instance in this case namespaces some namespace and then some part and then slash and the metric name that you specified in the Kubernetes world and if everything works out nicely you have a value that finally comes from Prometheus and just as a proof you know we have here my test setup I was simply executing five requests per second again it's the pot-info part and when you take this theory that we configured in the very last step of the configuration it should be at the very same value so I recommend if you do configure the Prometheus adapter do these kinds of sanity checks to see if the query is executed correctly if the metrics are being discovered correctly so this is a nice way to check this out future as you see this is quite an elaborate configuration setup and we spent some time we work at Red Hat and also to configure it correctly for our own purposes actually there was the motivation for this talk because we were sometimes confused by our own tools and we actually want to improve things on the Prometheus adapter side so first of all there is a very nice pull request by the community out there to add external metric support currently it is hosted under the username of Soliras who has been initially working on the tool we would like to move it to the Kubernetes organization obviously hopefully a year from now I won't need to spend so much time on explaining the configuration of the Prometheus adapter anymore we want to tackle this quite complex configuration and obviously since this is a pretty abstract discovery mechanism we recognize some scalability issues with the current approach so we would like to tackle the current issues with that one so we do plan a pretty beefy refactoring of the adapter itself in the future nevertheless for resource metrics we do feel that it's quite stable to be used as of today for custom metrics hopefully you learned how to do the mapping yourself so you can actually use it as of today too maybe the recommendation would be write rigid selectors to reduce the amount of metrics exposed inside the Kubernetes cluster finally HPA configuration once and that we will just spend one slide on it because we don't have a lot of time once you have your metrics ready and exposed you obviously can use them as any other metric inside the horizontal pod autoscaler configuration and in this case here I simply scaled this pod info part to based on the target average value of one request per second per part so that's about it yeah, you want to know? so if you want to get into running the Prometheus adapter and use all of this what we just explained the easiest is probably to use QPrometheus which is inside the Prometheus operator repository we ship Prometheus adapter preconfigured for resource metrics you still have to do some manual work due to the limitations we were just talking about for custom metrics and you can also check out the custom metric examples in the Prometheus adapter repository so for getting started just go and QPretel apply the manifests in QPrometheus oh and for the custom metrics there is a deploy sub directory inside the Kubernetes Prometheus adapter upstream repository itself so if you want to play around with that but again you may or may vary you may also want to mix a different adapter implementations depending on your environment so yeah how to get involved because this is a custom if you want to get involved we have ZIG instrumentation and ZIG auto scaling which are the special interest groups in Kubernetes and especially the Prometheus adapter is part of ZIG instrumentation and we have like both B-weekly I'm not sure auto scaling is like 3-weekly meeting sometimes and there is also a mailing list but you can also go into Kubernetes and ask questions about these topics so yeah I think that's it if you have any questions feel free and we are going to stick around afterwards as well questions cool as you head out if you find any trash please put it in the bins there oh we have a question hi thanks but my question is not related to this because you are I'm interested in the GoPath are you using this on production GoPath you are mentioning one of the creator of GoPath yeah I'm using it on a daily basis and I know like I don't know like 20 people that use it too so but we can discuss it afterwards okay does it have a matrix endpoint not yet okay no questions thanks folks