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First of all, I am neither an electronic nor a mechanical engineer, so if some of what I say sounds ignorant, that's most likely because it is.

I have been thinking about this for a while now. I love EVs and the fact that they are one of the best ways to cut down carbon emissions. On the other hand, I hate the fact that more and more modern vehicles are coming with a large amount of control being handed over to Electronic Control Systems. Would it be possible to have an EV that has little or no Electronic Control Systems in it? Is it possible to mechanically control features such as ABS, power-steering, etc without electronics?I mean, how much AI do you actually need in these vehicles? Are we just including it because we can, or because it is absolutely necessary? Essentially, is it possible to build an EV that would survive an EMP bomb?

Thanks.

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    $\begingroup$ Electric vehicles were popular in the early history of the car. Manufactures stopped making them in the 1910s. Most cars, where electric or internal combustion engine, don't need the amount of electronic control systems they currently have. $\endgroup$ – Fred Oct 22 at 13:50
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    $\begingroup$ No !!!!! You will need control systems whether mechanical, electrical, done in computer code or whatever. $\endgroup$ – licensed professional engineer Oct 22 at 19:03
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    $\begingroup$ As a cool example that proves the answer to your question is "yes", my dad owns a Jet Industries ElectraVan, which was produced in the late 70s and early 80s using the General Electric EV1 controller: forkenswift.com/electric-car-photo.htm?img_id=72 While you're driving down the road, the EV1 "sings" (very loudly) in way that sounds like a Therimin. I don't know that this device doesn't have a "computer" in it, but certainly it wouldn't be like anything we would think of today. $\endgroup$ – Sompom Oct 22 at 21:54
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    $\begingroup$ I suggest you should learn some microcontrollers. Get yourself an Arduino, make some little project, like a "useless machine" that turns itself off. You will see they are extremely useful and they don't have to be overkill. Whatever you replace the electronics with will be just as complicated as the electronics, anyway. $\endgroup$ – user253751 Nov 3 at 18:27
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    $\begingroup$ But the reason modern cars have such sophisticated electronics is because they can... if you can get 1% extra mileage by doubling the size of the code, then why wouldn't you? Code is "free". You don't need all that complexity to make the car work at all, you do if you want it to be the best car. $\endgroup$ – user253751 Nov 3 at 18:28
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Yes, it's possible, but electronics do it cheaper, lighter, and in a more sophisticated manner than what electro-mechanicals can do it. You can also tweak software to tune a basic design. With electro-mechanicals, the basic design has to be tweaked to fit the control system. (although which is easier to tweak at this point is a matter of opinion).

Having said that, I have no idea why modern cars need half a million lines of code to roll down the road. And I still operate equipment that has nothing more than an alternator, a fuel solenoid, a starter, and some lights. But even golf carts switched to electronic motor controls

Ward Leonard control was patented for electric vehicles in 1903.

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    $\begingroup$ Half a million lines of code isnt necceserily much code as such. $\endgroup$ – joojaa Oct 22 at 19:07
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    $\begingroup$ Yeah, given the modern trends in software development, most of that code is likely the never used library/framework code. $\endgroup$ – Ruslan Oct 22 at 21:29
  • $\begingroup$ @Ruslan: actually, car manufacturers are notoriously COGS (Cost of Goods Sold) conscious. If all that extra unused code ends up forcing the manufacturer to use a part that costs \$1 more, they won't do it (because \$1 per car x number of cars they make == real money) $\endgroup$ – poncho Oct 22 at 22:39
  • $\begingroup$ @Phil Sweet How much more efficient do you think the code makes the battery? $\endgroup$ – oiclid Oct 25 at 8:41
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    $\begingroup$ @oiclid Software can't do much about air resistance, rolling resistance, a hill, or hotel loads, but it is important for managing charge and discharge rates as a function of state of charge. BMS software has a significant effect on the total power throughput of the battery before it needs to be replaced. Perhaps the best thing it can do is manage traffic congestion and optimize routes in dense urban areas. $\endgroup$ – Phil Sweet Oct 25 at 12:38
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It has certainly been done. A friend of mine actually had a Citicar in the 1980’s. The design was very simple. Standard lead-acid batteries and a 12hp DC (brushed) motor. The speed was controlled by a series of relays that would engage was the accelerator was pushed farther in. No regenerative braking. No power brakes or power steering. Max range and speed of around 40 miles and 38 mph.

A big thing computer assistance brings is complex feedback loops. For comparison, modern electric cars (and electric power tools) now use three-phase AC motors, often called “brushless DC motors” by power tool marketing. The reason is higher reliability by eliminating the brushes that wear out, higher efficiency, and vastly higher starting torque. However, it means that speed is controlled not by a variable resistor or a set of relays in the gas pedal/trigger, but by a microchip that reads the trigger input and the current rotation of the motor and decides the duty cycle of the inverters that are generating the three-phase power for the motor. Yes, your cordless drill has an extremely simple computer inside it. Lighter, more torque, longer battery life, longer motor life.

Just an example. Similar control systems have improved gasoline engines from 25% to as much as 80% fuel efficiency in my lifetime.

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    $\begingroup$ What gasoline engine that has 80% efficiency are you thinking of? $\endgroup$ – Transistor Oct 22 at 21:45
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    $\begingroup$ That might be 80% of Carnot efficiency, but you're still losing more than 75% of the chemical energy in the gasoline as waste heat. $\endgroup$ – Mark Oct 22 at 23:11
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    $\begingroup$ Why can I not find the analysis? The study combined the Mercades F-1 engine (>50%) with heat reclamation and regenerative braking. Lesson to self, find references before posting. $\endgroup$ – UrQuan3 Oct 24 at 0:37

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