Make Your Car Electric for 5K in Less Than a Day
jamesdysonaward.org
jamesdysonaward.org
Nobody on this process must have ever been involved in DFM.
You might have missed some key points in the pitch. Slide 4 has e-hydraulics for steering and braking.
As the other commenter pointed out, there's a lot of hand-waiving going on by the kid who won the contest; it's like the farside comic where there's a giant "magic happens" in the middle of a board full of mathematic scribbling.
For example: running HVDC to the engine compartment (for the AC, power steering, and vacuum pump) from the spare tire well in a vehicle whose undercarriage isn't designed for it requires pretty substantial armoring.
The other problem: in-wheel motors are not new (Mistubishi sunk a LOT of R&D into it), and they haven't taken off for a reason.
They massively increase unsprung weight. Your average car wheel weighs maybe 30-40lb at most. He's probably doubling that. That means atrocious ride quality and traction issues, because the tire's going to be bouncing around like crazy due to the suspension not being designed to dampen that much weight.
The motor is also subject to all the vibration normally soaked by the suspension and vehicle frame. Trying to get an electric motor to withstand that sort of vibration is not a trivial problem.
This is just a bunch of hogwash from Dyson. The kid figured out that what they care about is a nice big fat PR grabber, and he gave them one.
It's not possible for a reasonable price. NRE costs per model would be high, making a farce of "Make your car electric for 5k".
For the mechanic installing the device, you have to have an installation manual listing where every cable and hose needs to go and be secured. And you need to choose well, because if it rubs anywhere: recall and fix (is there enough money in $5k for recalls? No).
You have to hack the ECM, /per model/, to allow you to drive without the engine actually running.
It's preposterous.
I’m planning on doing something similar on my old hilux. The lack of power steering or power breaks or any auxiliary system that relies on the engine simplifies the build substantially.
> REVR is a retrofit kit that incorporates all systems required for the conversion of a light ICE vehicle to hybrid electric.
While using the gasoline engine, the power accessories (power steering, power brake assist, ABS!) are functional, but when the gas engine is powered off, you'll have none of them? That's going to get someone killed. And on top of that, the climate control issues -- A/C won't work, and the heat will only last so long as the gas engine is preheated and then only briefly as the coolant isn't being circulated.
The concept of hybrid is an invisible marriage of gas/electric propulsion brought to us by Toyota who perfected it in the Prius. This is just a hack as far as I am concerned. I would be more impressed if the engine were removed entirely, and this motor were bolted up to the transmission as a replacement flywheel.
You still reduce fuel use, don't need to change any other parts to work without the engine.
You just basically need to know when the accelerator and break (and perhaps clutch?) Were pressed, and perhaps change accelerator response to make it feel more natural.
The price of a used Leaf in the USA can be $3000: https://seattle.craigslist.org/sno/ctd/d/everett-2013-nissan...
So if you just want an EV, you can get a whole working car, with more range, for less.
I'm just hopeful that there is some way to retrofit the millions of existing ICE vehicles out there in a way that's cost-effective.
No, you'd buy a Prius instead, because it'd work better and be cheaper.
Also ford going to offer a conversion kits with Mach-E crate motors, but appears the supply shortage and rising prices put a pause on it.
https://electrek.co/2021/11/03/ford-is-selling-mach-e-crate-...
I'm not sure how "available" it is in the real world, and I'd note that it is sold through authorized installation centers rather than direct-to-DIYer.
Ford has a new electric truck platform in development, the "T3". This is supposedly electric from the ground up, unlike the F-150 and Ford Transit, which are modified versions of gas vehicles.
Cost: I’d assume the cost is for a single motor; that would be a fairly unstable vehicle to drive with different left/right turning behavior.
Wheel offset: Mounting the motor here will require a pretty massive increase in wheel offset or a pretty massive outward push of the wheel centerline, with each having its issues.
Brake heat: If the stock brakes are used they will likely cook themselves and the motor. You are essentially requiring the electric motor to do all the braking, or else developing a hybrid braking system. Using hydraulic brakes on just one axle is a non-starter for safety reasons.
Very clever idea, and maybe they can make it work. There are more than the reasons I listed as to why this hasn’t been pursued previously.
??? Why?
Doesn't it take the same energy to stop a car disregarding what kind of force put it in motion?
For reference, it’s not uncommon to see temperatures of 1000F or higher after a single highway speed stop on the front rotors of most passenger vehicles. Having that amount of heat that close to the motor is something that needs to be designed around. The rear brakes will typically be 200-400F cooler depending on the weight bias, but that’s still not a trivial amount of heat.
b) An electric car is going 60 mph and brakes to a standstill.
How does one generate more heat than the other?
Why would the brakes "cook themselves" in b when they don't in a?
>For reference, it’s not uncommon to see temperatures of 1000F or higher after a single highway speed stop on the front rotors of most passenger vehicles.
I'd like to see that reference. 1000F is F1 tier, lol.
Yes, maybe that's why they only add motors to the back wheels (x2).
You can't just start taking parts off of cars without understanding the impacts.
Also, ebrake, etc. These things are required by law.
Handled by the motor, the motor is the brake IIRC?
Regenerative braking doesn't replace the need for brakes. There are lots of reasons why, safety reasons, that you need thr brakes to work even if power fails, when the car is parked etc.
Actually, I think it is perfectly practical for a DIYer like me, with the following small caveats (as opposed to your large caveats):
1. Use a front-wheel-drive car as the donor.
2. Mount two motors on the rear wheels (one per wheel).
This way:
1. The first instability from torque steer due to driving only a single wheel is gone - car will accelerate in a straight line because equal power is provided to both wheels. The second instability from larger unsprung mass is easier to mitigate on non-steering wheels (i.e. the rear wheels). The third instability from increased wheel offset relative to the kingpin is completely removed.
2. Modifying the offsets on the rear axles (specifically, reducing them) in a FWD car is simpler[1] than doing the same on the drive wheels. If a double-wishbone design is used, it becomes a little complicated, but no more complicated than doing the same on the front.
3. The rear wheels do (IIRC) ~10% of the braking work that the front wheels do, so there is less heat generated. Until recently, quite a lot of the low end cars came with drum brakes on the rear anyway/
I'm curious why he placed the prototype on the front wheels - he must have had a good reason. After al;, someone who came up with the design itself isn't stupid, and someone who actually modded the car knew what they were doing as well, so there's probably a good reason for modifying the front wheels and not the rear.
[1] Still complicated, but a lot simpler - because the wheels don't steer there is no need to worry about the steering geometry, track rods/steering rack modifications, etc.
> A retrofitted car can have two or four of these electric wheel motors
One motor definitely doesn't seem like a usable product without other changes to the car. Unless we're making an electric Messerschmitt Kabinenroller.
I’d love to see an electric three wheeler, maybe like the old heavy duty Mazda trucks!
> REVR could cost as little as $5k without rebates and can be installed in under a day.
What are the conditions in which it "could" cost this amount, and has it already been achieved?
Some newer vehicles have a “belt-starter-generator” that’s just on the accessory belt, like the Fiat 500, and a tiny <1kwh battery, but dunno why it’s not expandable or why nobody makes something bolt-on for ICE vehicles that are common. Companies make a bolt-on supercharger kit for the Corolla, but nothing like this that could be useful in fleet/delivery/taxi applications.
I guess gas is too cheap to plug in one’s vehicle for a 10% reduction in fuel consumption.
Basically a lot of the extra things like power steering and water pump are electric instead of engine driven. And the generator is set to run as much as possible only when decelerating / braking. So it's using energy that would normally go to waste in a non-hybrid car. The battery is 1kwh which is enough for this purpose.
They haven't incuded the air conditioning pump in this, probably because it requires more power than the electrical system on a non-hybrid car could handle.
While the ICE would still move at all times valves could stay up for 1 (only 3 firing) to 4 cylinders (no ignition at all) to eliminate pump loss (there's still friction loss). Sadly the electric engine is a bit weak for full EV operation except coasting but I found the approach quite elegant.
Smart.
You save considerably more energy by slowing down 10mph than you do by turning off the AC.
Having more mainly comes in handy for ascents and acceleration, though electrical loads are a bit more constant.
(Another gripe of mine is how big engine sizes are in North America, it's not like Europe has low speed limits and no mountains)
ICEs are incredibly inefficient, most of the petrol energy is lost to waste heat. Something like 60+% IIRC.
On my MX-5 when I ditched the AC compressor and switched to an OEM manual rack the car picked up some pep but I observed no significant difference in MPG...
IIRC the major way to move the MPG needle on these things is to increase the compression ratio, since that's directly linked to the thermal efficiency.
A problem specific to ICE in a vehicle application is that at the engines end up running in conditions away from their peak efficiency point due to vehicle load, terrain and traffic conditions. That is where hybrids are supposed to pick up their efficiency by letting the ICE turn off completely in the regimes that force the engine to run at low efficiency points. Such as idling where the MPG is zero.
Off the roads there is less regulation and that is where 90% of the pollution happens.
What a time to be alive.
> The James Dyson Award supports budding design engineers at the start of their careers. If you’re a current student or recent graduate with an idea that solves a problem, we want to hear about it. We’ll be equally impressed by rough-and-ready prototypes as we will by mass market-ready samples.
They're not worth spending big bucks on, but an EV retrofit kit that is 'good enough' would be worth it.
Extra points, if your middle class 'car enthusiast' type could do the majority of the retrofitting (or all of it) himself.
The aftermarket car culture has been waning a bit and safe electronics could be a big lift.
$5k seems cheap, even for a retrofit, I can imagine building a new car should be even cheaper than this. Of course there is the body of the car, interior and suspension, but the whole package together should become cheap as motors and batteries become ubiquitous ?
I get it for preserving older cars for movies, etc. But a corolla? Thats like replacing screen on iphone 6 and hoping it’s worth something.