Torque Vectoring

more motors
more hype

torque vectoring by braking can have uneven brake wear

One motor per wheels allows torque vectoring not through braking but by actually just not putting that rotational energy into the wheel, IE the wheel is driven at a lesser rate, rather than the brakes being activated to slow the wheel down because the torque is instantaneous


Differentials can get complicated or can lead to odd handling characteristics on the street, but I'm think more like old school detroit lockers or a mini spool rather than something electro magic

>>16923832
>One motor per wheels allows torque vectoring not through braking
Regenerative braking uses the electric motor to brake and charge the battery.

>>16923889
That is correct, I should have specified braking by using the pads

Or like in the new NSX, the computers do their thing and tell the motor to dial back to torque being applied for most efficient operation

In short: One 50 hp motor per wheel means that each wheel can only ever be supplied with 50 hp maximum. One 200 hp motor for the entire car with torque vectoring differentials means that all 200 hp can go to as little as one wheel.

>>16923600
Why can't we have both?

>>16923943
Braking reduces this efficiency though. That's not real vectoring.

Limited slip diffs have X amount of preload (not sure if it's called that: "torque required to slip" = preload for now).

That means in order to get the diff to start to slip (send power to other wheel) you're wasting at least the preload torque into the brakes.

With real torque vectoring using an e-Diff, you "brake" in the diff (not entirely sure how it actually works) but that torque is rerouted into the other side, not lost to brakes. I would say it's magic and pixie dust but Mitsubishi did it so it's probably pretty simple.

>>16924735
Can a torque vectoring differential apply negative torque while the vehicle is moving in the positive direction, or is this unique to electric vehicles with one motor per wheel?

>>16924958

Like a Bobcat?

>>16924958
Dont think so. They're clutch based. Again, not sure exactly what goes on inside but I believe that clutches control a set of gears in the diff. Effectively what this means is that the torque is split into 3, some to each normal drive axle and some to this extra gearing. Computers plus clutches choose which side the overdrive gearing ultimately helps power.

Net result is that you always have all power going to the wheels instead of cutting power to motors or the braking type, which is a budget way to do torque vectoring using more standard LSDs.

>one motor per wheel
I assume you are only referring to electric cars then, and seeing as there's an over 5k lb car that is going 0-60 in 2.4secs with 245 front, 265 rear regular street tires, and uses normal open diffs, I'd say there's little performance benefit running two motors per axle on tarmac. There could definitely be interesting applications for off road/rally when electric cars emerge there though.

I've always thought that one motor per wheel was stupid because if one motor gets worn out it then they're uneven all the time but with a single motor they're still even, just less power.

>>16923600
Literally don't listen to any of the 200+ responses you're about to get. Nobody on /o/ knows jack about cars, yet alone fancy shit like this. I literally ride a bus.

>>16925465
exactly why this will always be a meme.

>>16925393
>brosciencing this hard

>>16925465
I think it would be more reliable than one motor assuming the torque vectoring computer could correct for one of the motors not working if you are willing to put up with reduced power.

>>16924735
>With real torque vectoring using an e-Diff, you "brake" in the diff (not entirely sure how it actually works) but that torque is rerouted into the other side, not lost to brakes. I would say it's magic and pixie dust but Mitsubishi did it so it's probably pretty simple.
It's just an active differential. Mitsubishi AWC and Honda SH-AWD both do it. I'm sure others do it, although not many. It's an electromagnetically driven clutch in the differential, taking input from wheel speed, engine load, throttle position, yaw sensor, and steering angle.

>>16924958
basically this. The 1 motor/wheel can do negative torque while the e-diff/diff can't. A car with 4 motor all wheel drive could pivot in place while the traditional couldn't. The only reason we haven't seen this the amount of programming and complexity is rather high. The top FSAE electric teams use in-hub electric motors and can do some stupid silly stuff with it. We went with one motor with a traditional diff as it was a lot simpler and cheaper.