The super simple and cheap car of the future


With Mobility on Demand, you don't buy a car, you buy rides. That's certainly Uber's plan, and is a plan that makes sense for Google, Apple and other no-car companies. But even Daimler, with Car2Go/Car2Come, BMW with DriveNow and GM with Lyft plan to sell you a ride rather than a car, because it's the more lucrative thing to do.

So what does that car of the future look like? There is no one answer, because in this world, the car that is sent to pick you up is tailored to your trip. The more people traveling, the bigger the car is. If your trip does not involve a highway, it may not be a car capable of the highway. If your trip is up to a mountain cabin, it's more like an SUV, but you never use an SUV to go get a bottle of milk the way we do today. If it's for a cruise to the beach on a sunny day, the roof may have been removed at the depot. If it's for an overnight trip to a country home, it may be just beds.

I outlined many of these changes in this article on design changes in cars but today I will focus on the incredibly cheap and simple design of what should become the most common vehicle made, namely the car designed for a short urban trip by one person. That's 80% of trips and around 45% of miles, so this should be a large fraction of the fleet. I predict a lot of these cars will be made every year -- more than all the cars made today, even though they are used as taxis and shared among many passengers. What does it look like?


A car for 1-2 people will be small. It will probably be around 1.5m wide, narrow enough that you can fit two in a lane, and have it park very efficiently when it has to wait. If it's for just one person, it won't be very long either. For two people, there will be a "face to face" configuration which is longer and an "tandem" configuration which is a bit shorter. The 2 person vehicles aren't a lot bigger or heavier than the one person, so they might be the most common cars, since you can serve a solo rider fairly efficiently with one, even if not perfectly efficient.

A car that is so narrow can't corner very fast. A wide stance is much more stable. There are a few solutions to that, including combinations of these:

  • The wheels bank independently, allowing the vehicle to lean like a motorcycle when in corners. This is the best solution, but it costs some money.
  • Alternately it's a two wheeler, which is also able to lean, but has other tricks like the LIT Motors C-1 to stay upright.
  • It's electric, and has all the batteries in the floor, giving it a very low center of gravity. (One extreme example of this is the Tango, which uses lead batteries deliberately to give it that stability.)
  • It never goes on fast roads, so it never needs to corner very fast, and its precision robot driving assures it never corners so fast as to become unstable, and it plans its route accordingly.

Not super aerodynamic

The car already has a big win when it comes to aerodynamic drag by only being half-width. The non-highway version probably gives back a bit of that because you don't need to worry as much about that if you are not going fast. Energy lost to drag goes up with the square of velocity. So a 30mph car has 1/4 the drag of a 60mph car, and 1/8th the drag of a similar car of full width. The highway car needs to be shaped as close to a "teardrop" as you can, but the city car can get away with being a bit taller for more comfortable seating and entry/exit. The most efficient and safest design would be a teardrop with a backwards-facing passenger, but many people don't like facing backwards. Though in a forward crash it's the best direction to face.

Electric powertrain

You don't care about the powertrain in your taxi, but the fleet manager cares, and various reasons suggest electric might be the way here, especially for the city car. Public policy may also push in that direction, for zero tailpipe emissions and lower overall emissions in non-coal areas. The main disadvantage is the downtime of the vehicle during recharge. That's not an issue for you as the passenger; you never see that. You can answer it by having more cars, battery swap or occasional supercharge sessions during the day.

The electric powertrain is super simple compared to today's cars. This future car has just a tiny number of moving parts compared to any gasoline car. It's easier for innovators to build and experiment with and easier to maintain. It has all the torque you need (you don't need much) and regenerates energy in city driving. It stuffs all the weight into the floor of the car for stability and is quiet and smooth. As battery prices drop, it becomes very hard to beat once you remove the range anxiety and recharge anxiety questions, as a taxi inherently does. (You don't get sent a taxi without the range for your desired trip.)

Much, much simpler (and cheaper)

Just as the electric powertrain has vastly fewer parts than the ICE powertrain, this car also is much simpler. While there will be cheap versions and luxury versions, many of the things we see in cars today vanish. For a short urban trip, a "box on wheels with a chair in it" is not a bad description of what you actually want.

The body

Some customers are still going to want some style, of course, but the bodies will be simple. Possibly just one door -- the car parks in a way that your door is pointing the right direction. If it's for tourism, a big wide windshield might still be present, but otherwise it's easier and safer to have a segmented window. (You do need a 2nd emergency exit, some panel that can be kicked out.)

If it's a LIDAR car it doesn't need full headlights, just LED running lights so other cars can see it at night. It doesn't drive on dark rural roads, remember, only lit streets. Being electric it has no need for a grille. It probably doesn't have a hood, because they probably unscrew the body at the depot during the rare service that electrics need. It doesn't have a trunk either, just a place inside to put stuff. (Some vehicles will have trunks or other interior space, and will come when you say you have stuff to move with you.)

It does have mounting points for robocar sensors of course, that's the one thing that adds cost over a regular vehicle.

We probably still want side windows that can come down, and locks we can control, but the windows might be simpler than they are today. The window on the side that has no door is probably easier to build. Unlike a human driven car, however, these windows will legally be able to tint. LCD variable tint might be a nice luxury feature.

No side-view mirrors, of course, and no rear-view mirror either. But that's inside.


It does have to be crash-worthy, of course, and in spite of intuitions it is possible to do that on smaller cars, it just costs money and weight to create the crumple zones and other structures, plus the airbags. A robocar has some special abilities when an accident is inevitable, to turn the vehicle if it can to direct the impact through the crumple zones and to position you well for the airbag. (It's not out of the question a car could even spin itself to make you take the impact backwards, if the tires can offer that sort of force.) In time, as more cars on the road become robocars and accidents become more rare, we might see a reduction in the amount of weight that has to be devoted to passive crash protection. With no steering wheel, there is more room to absorb energy into a bigger airbag if you are thrown forward, and bags can be triggered even slightly before impact.

The interior

The seat can be spartan or luxurious, but it may not need to move around as much. If you're alone in the car it would be fixed at maximum legroom. Luxury vehicles will have motorized recline or other adjustments as they do today, but since the trips are short, fancy features like lumbar supporters and massage are less important. Armrests might be fixed.

You'll want places to put things, particularly cupholders for drinks and charging stations for your devices, and a convenient place, probably at your feet, to put your bags.

There will be a fold-out table, and also a fold-down screen. For security reasons, it should not offer a keyboard or mouse that you would connect to your devices (that means giving control of your devices to a potentially hacked keyboard) though if it has its own small general purpose computer it could offer those. Mostly the screen would exist for use by your devices, when they want to offer you a bigger screen for work or videos.

You don't really need a glove compartment since you don't keep things in this car, but it might want to have a small cabinet with useful supplies that people need -- tissues, cloths to wipe up spills, and possibly a booklet for major failures.

The dashboard

The most obvious thing missing though, are the controls and the dashboard. They are almost entirely gone. You will use your own phone for entertainment and information, even to issue commands to the car. A small tablet might be found as well, showing background information and allowing control in situations where your phone is unsuitable.

While it would require some standardization, it would be nice if there were a slot that could accept most phones and tablets and offer them wireless power, plus connectivity to the screen and a one-way feed of data from the car. (For security reasons, communications to the car's driving system from your untrusted phone must be tightly constrained.) It's possible, if new, that the car might offer a superior mobile data connection to your device, since a robocar needs its own mobile data connection and has the opportunity to have a well placed antenna and more power. On the other hand, you may still want to use your phone's data connection as your phone will usually be newer and have a better one.

There might be a pop-out control for the car in breakdown situations, such as a handlebar that pops out or a joystick that lets you move the car slowly, video-game style. It would not be for driving at speed or even human takeover in an accident situation, just a low cost device to let you do things like get the car off the road in the event of major breakdowns. Cars which go out into the country might have fancier controls to let you drive dirt roads, driveways or other unmapped spaces.

Will there be a fancy sound system? Well, people will want music and video in the cars and the electric engines will be less noisy. On the other hand, quality noise cancelling headphones might offer an even better experience, aided by only a subwoofer or vibration elements in the seat. And they could even offer different audio to each person if there are multiple occupants. They will probably be cheaper than a fancy sound system, too, and can be brought by the passenger if some cases. They also can be easily upgraded.

More economical cars might have none of this -- no screen, a fixed seat, bring your own headphones -- and still be quite suitable for many riders. You aren't spending an hour in this thing, you're spending 15 minutes. You will mostly spend it fiddling with your phone and care about little else.


We will want climate control, but robotaxis offer some interesting alternatives. While heat will mostly come from the battery cooling system, it's possible that some heat and cooling could come in a much simpler way. The car could stop by a depot for a load of ice or other pre-chilled coolant good enough to keep the vehicle cool for an hour or two. Then it would reload. With short rides, you won't know or care how it's done, but this could be a better choice than having an air conditioner and sucking battery power. Heat in very cold areas could also come this way, or with some GHG emissions, by burning a liquid fuel, or a biofuel.

The small electric taxi may also be granted permission to go inside buildings, so you enter and leave primarily in climate controlled places, reducing its need for powerful climate control. During bitter cold periods, the cars could go to heating stations (or electric stations) to keep their interiors and batteries warm.

Drive systems

While this car strips out things like pedals or a steering column, it does have a few things over and above the traditional car. It needs two redundant steering systems and two redundant braking systems in particular, because the human is not there to provide alternatives if one fails. And of course it has the sensors and computers to make it drive itself.

The suspension also changes. It may get more expensive in higher end vehicles as it offers a super smooth, "no feel of the road" ride to those that want it because they are no longer driving.

The Big Picture

This car is small and simple, much fewer moving parts and general parts than the typical car made today. It's light and efficient and electric.

Small, simple and light translates into cheap. Very cheap. As the computer/sensor pack drops down to the $1,000 range over time, and the batteries drop in price to $150/kwh, this car becomes a lot cheaper to make than traditional cars.

Cheaper to make means cheaper to sell. Sold by the mile for around 25-30 cents/mile (compared to today's cars which are around 60 cents/mile if you could buy them by the mile) this is cheaper even than a bus ticket for many rides. Billions more people will be able to access car transportation than can do so today, when you must put down many thousands of dollars to get in the game. That means big sales of these and other vehicles, which also means even lower prices.


There are many things in this blog post that struck me as quite unnecessary for cars where "you aren’t spending an hour in this thing, you're spending 15 minutes."

For example:

"Some customers are still going to want some [body] style" (implies vehicle ownership; when you get a taxi today you don't care about its style)
"There will be a fold-out table, and also a fold-down screen." (not useful for trips of only 15 minutes)
"a small cabinet with useful supplies that people need" (just like taxis have now...)
"the car might offer a superior mobile data connection to your device" (no chance)
"Cars which go out into the country" (nah, these cars will be restricted to roads like the way shopping carts have wheel locks that prevent them from leaving the supermarket parking lot)
"a subwoofer or vibration elements in the seat" (and a unicorn)

"You will mostly spend [your 15 minute trip] fiddling with your phone and care about little else." This. And only this.

Some customers want to show up with style and will order vehicles they like.

If you have a laptop and are working on it, you want that table.

We now have an great example of a simpler smaller lightweight vehicle on the roads....the Elio. At about $7k it's much cheaper than any available electric. Your suggestion that EV's are 'simpler' is false of course, since the number of components in an ICE is about the same (or even less) if you don't count the number of cells in a battery or components inside the ICE.
Would you consider an Elio a reasonable Taxi, I certainly would not? EV counterparts will be about the same, just not up to the quality you want for a ride.
Your whole hypothesis is fundamentally flawed however. The prediction that there will be a very large and varied autonomous vehicle type fleet (SUV's through to the 2 seater lightweights) available for TAAS is simple fantasy, at least for the next 15-20 years.
The available business models that might be profitable for the next ten years limits you to in essence car/taxi type product, there won't be any sleeper's, boat towers, Skiing holiday SUV's, off road SUV's, but you might just get your drop down table/tray for the laptop. Even Google have now gone for a multi-passenger people mover (the FCA Pacifica)as their first real attempt at a deliverable product.

I agree if you consider each battery cell individual you have more parts in the battery pack. But I view having 1,000 of the same parts as different from 1,000 different parts. The elimination of the other ICE parts saves a lot of parts (especially moving parts) and the elimination of the dashboard saves a ton more.

The most common car will be the small taxi, but you need more than that in your fleet --including traditional 4 passenger size cars. You can always serve one person with a larger car, it's just less efficient. (Car rental companies often give you a fancier car than you reserved for that reason.)

The SUVs and sleepers do not need to be many because they will be more for reserved trips than on-demand rides. In fact, in any self-drive taxi fleet is a pile of traditional human driven cars along the routes out of town, and your robotic taxis take you to them for a quick (zipcar style) transfer to your road trip car, which you will drive, or do some of the driving in. In fact it may be a partnership with zipcar.

Most modern 4-6 cyl ICE have under 500 parts by the way so it's difficult to generalize on component levels. You might be better to compare reliability and maintenance costs.
Most battery systems and electric motors have the advantage that they need little maintenance, so you could propose that as a benefit. However an ICE can be reconditioned when it's done too many miles, a battery typically cannot, so as they degrade they are simply scrap. EV TAAS vehicles are likely to see at least one battery swap in their usable life raising total costs.
In the rest of the vehicle there simply are not enough component differences to make a difference.
Elimination of the dashboard would happen whether EV or ICE if the vehicle is I see no difference there. You might save brake pads in an EV, but you still need the hydro-mechanical brake system.

You make exactly my point on business models, the likelihood is that you will see mostly 4 (or more) seater autonomous vehicles, with a large enough fleet to serve peak commute times. For non-peak times the vehicles will be just parked as manual vehicles are today, which reduces overall efficiency.
You can see the initial stages today, with several 8-12 seater low speed vehicles on the market (or in late prototype stages). This trend will obviously continue, and the more of these that arrive the less attractive it is to develop 1,2 seater configurations..
Proposing lightweight vehicles will be released en-masse with huge uptake seems overly optimistic. The vast majority of vehicles on the road are 1.2k lbs and above. EV's are typically must heavier than their ICE counterparts, for example the Elio is 1.2k lbs and an eSMART about 1.7k lbs. Batteries for energy storage are very inefficient.

Correct, the simplicity that comes form the power train is independent of the simplicity that comes from things like having no dashboard, or one door, or a simpler interior. I am listing all the things that make the vehicle simpler and cheaper. Of course, one of the biggest is just being smaller.

The move to electric is not assured. What is key is that many of the disadvantages of electric are eliminated for the passenger -- range anxiety and recharge time anxiety. Also hunting for charging where you need to park. However, with those removed, the other disadvantages (cost and weight) still exist and I am predicting the switch based on the forecasts of $150/kwh or less for the batteries.

However, simple ICE engines are also possible. In fact, they are also better off because the city cars have no need for high acceleration or power (one of electric's advantages, actually.)

But I do feel that the 1 seaters will be much cheaper to make than the 4 seaters and cheaper to run, so there will be demand for them, because a ride in one will cost less, and they also will have better ability to go through traffic -- even lane splitting -- and will be cheaper to store/park. And then the day will come when there will be infrastructure just for them -- underpasses and elevated paths only for use by narrow, light vehicles.

If driverless autonomy succeeds and shared TAAS becomes common, the most likely vehicle size would seem to be 4 seaters and above. If the fleet is sized for commute/peak then there will be lots of vehicles parked somewhere off peak. It would seem to make little economic sense to create 1-2 seaters if you have lots of 4 seaters parked. The difference in energy efficiency is unlikely to offset capitol costs.
Underpasses and elevate paths seem to make no sense at all if it's just for 1-2 seaters....there would be no need or advantage for this infrastructure off peak, and the cost would appear immense. Since you are normally vehemently against any infrastructure changes to support automated vehicles, I'm surprised you'd suggest this course.

Assuming 4 seaters and above seating would be side by side seating:

Tandem seats have the advantage to occupy less width. Vehicle width causes congestion. With the eventuality of narrow cars, government entities will tax side by side seated cars for the congestion they create. Therefore, tandem seating has enormous value added attributes over side-by-side designed cars.

Half-width vehicles have half the drag, and half the weight. Half-width, half-length vehicles will have even less weight. All of these mean less energy to move them and less manufacturing cost. Less weight of vehicle also makes the battery more productive in an electric vehicle. There is a virtuous circle with electric cars -- make the car lighter and it needs less battery to move it, and that reduces the weight even more.

If people buy rides using autonomous electric car inthe future, every city has to deal with autonomous taxi company or car sharing company?
If so, that can be change today's city development plan. People do not need to prepare private parking space, right?
How about shopping daily goods on week day or weekends? Do people have to ride on the autonomous car to buy something to any shopping center?

Can autonomous car run an errand alone to buy daily goods to shopping center for its owner or borrower?
Shoppers can order their goods using their online devices and they can let their autonomous car to pick their goods up without them, I guess.
If so, the building space will be changed a lot.
Shopping centers can introduce kind of dive-through line for autonomous cars, instead of the traditional huge parking space.

Autonomous car sharing could induce dramatic change in human life style and city development plan such as road, parking space, etc.

Add new comment