{"action":"created","issue":{"url":"https://api.github.com/repos/openETCS/modeling/issues/597","labels_url":"https://api.github.com/repos/openETCS/modeling/issues/597/labels{/name}","comments_url":"https://api.github.com/repos/openETCS/modeling/issues/597/comments","events_url":"https://api.github.com/repos/openETCS/modeling/issues/597/events","html_url":"https://github.com/openETCS/modeling/issues/597","id":96752903,"number":597,"title":"Fundamental issues about Amsterdam- Utrecht track model","user":{"login":"mairamou","id":11831051,"avatar_url":"https://avatars.githubusercontent.com/u/11831051?v=3","gravatar_id":"","url":"https://api.github.com/users/mairamou","html_url":"https://github.com/mairamou","followers_url":"https://api.github.com/users/mairamou/followers","following_url":"https://api.github.com/users/mairamou/following{/other_user}","gists_url":"https://api.github.com/users/mairamou/gists{/gist_id}","starred_url":"https://api.github.com/users/mairamou/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/mairamou/subscriptions","organizations_url":"https://api.github.com/users/mairamou/orgs","repos_url":"https://api.github.com/users/mairamou/repos","events_url":"https://api.github.com/users/mairamou/events{/privacy}","received_events_url":"https://api.github.com/users/mairamou/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":8,"created_at":"2015-07-23T07:43:56Z","updated_at":"2015-07-23T08:56:44Z","closed_at":null,"body":"During the documentation work on Amsterdam Utrecht track model I came across a real conceptual problem.\r\nAfter discussion with @JakobGartner it is like this:\r\n\r\n- The balises have been modelled using the planning documents from ProRail\r\n-  the packets have been modelled using the packets received by the JRU\r\n\r\nWhile analysing the balise positions against the linking information, I could see that the two are not consistent.\r\nThis is a **static error** as this type of inconsistency does not have anything to do with possible onboard or JRU inaccuracies. \r\n\r\nI had another look at the JRU data. \r\nThe JRU also recorded the distance from the LRBG and the DOUBTOVER/DOUBTUNDER values.\r\nBut they are not part of the track model of course but only a documentation of the onboard calculation (which again mixes many errors including odometry)\r\n\r\nOur conclusion is:\r\n\r\n- The plans are just plans, apparently the real positions of the balises are not very much what was planned (errors up to 9m)\r\n- Probably, the Packet 5 data are more precise than the data in the engineering plans, if not the track could not have been gone operational\r\n--> we should correct the balise positions for *this iteration* to make them consistent with the linking information. If not, we will always run into errors without meaning. (we know already that the two datasets from ProRail/ from the packets also from ProRail) are not consistent)\r\n--> we could think about using the additional JRU data about \"where a balise was actually found\" in a next iteration track model/and/or an odometer error model. \r\n\r\nIf you all agree, I will sit down and build a version of the track model that moves the balise positions to a location consistent with the linking information. \r\n\r\n\r\n\r\n\r\n"},"comment":{"url":"https://api.github.com/repos/openETCS/modeling/issues/comments/124026254","html_url":"https://github.com/openETCS/modeling/issues/597#issuecomment-124026254","issue_url":"https://api.github.com/repos/openETCS/modeling/issues/597","id":124026254,"user":{"login":"mairamou","id":11831051,"avatar_url":"https://avatars.githubusercontent.com/u/11831051?v=3","gravatar_id":"","url":"https://api.github.com/users/mairamou","html_url":"https://github.com/mairamou","followers_url":"https://api.github.com/users/mairamou/followers","following_url":"https://api.github.com/users/mairamou/following{/other_user}","gists_url":"https://api.github.com/users/mairamou/gists{/gist_id}","starred_url":"https://api.github.com/users/mairamou/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/mairamou/subscriptions","organizations_url":"https://api.github.com/users/mairamou/orgs","repos_url":"https://api.github.com/users/mairamou/repos","events_url":"https://api.github.com/users/mairamou/events{/privacy}","received_events_url":"https://api.github.com/users/mairamou/received_events","type":"User","site_admin":false},"created_at":"2015-07-23T08:56:44Z","updated_at":"2015-07-23T08:56:44Z","body":" \n\nWe had a file with the planned engineering positions (which are the same\ndata as you find in the plans that Baseliyos has used to describe the\nUser Story \n\nWe also have a more detailed file with distances to some locations on\nthe track (which I don't really understand) \n\nWe have no file that is consistent with the packet data \n\nI think maybe the files we have were the input to whoever built the\ntrack \n\nand the packets are the output :-) from whoever built the track \n\nOn 2015-07-23 10:49, Jan Welte wrote: \n\n> The only point I'll never understand is that there has to be a docuent somewhere which lists the real positions, since the data for the packets has to be created depending on the positions. But that's a question for another discussion. Nothing which helps us at the moment. \n> \n> --\n> Reply to this email directly or view it on GitHub [1].\n\n-- \nMairamou Haman Adji\nJunior Software Developer\nResearch Fellow\n---------------------------\nLEA RAILERGY\n \n\nLinks:\n------\n[1]\nhttps://github.com/openETCS/modeling/issues/597#issuecomment-124024451\n"}}