Trike with all wheel drive?

I've been fortunate enough to be able to build a cromotor powered hardtail bike this summer. With a kelly controller it behaves nicely at low throttle, but twist the throttle and it most certainly will try to throw you off. Now it looks as if I will have another chance to build something absolutely crazy, but the question remains; What?

My budget is the equivalent to ~6000 USD and while I do want to build another motorized bike - this revision should be rideable for just about everyone. I live in Norway and in the winter it is icy and snowy. Four wheel drive cars are very popular. I've yet to see an all wheel drive trike completed.

I would therefore like comments on this setup:

• 2x direct drive front motors
  Geared rear drive, MAC
  Kelly controllers all around, working in balanced/torque mode
  Powerful battery. Power before range
  Tadpole trike as starting point

Dual front direct drive motors will allow torque vectoring, while the rear motor only is added for peak power output. I'm just about done with a M.Sc EE, so I'm fairly certain that if I do not explore torque vectoring myself - I'll have someone else look into it. High power hub motors will allow swift acceleration, but the trike will go into 60+ kg territory.

As said, any hints and tips are greatly appreciated.

Torque vectoring would work best if the rear wheel is a larger caster. Then you have the same thing as a zero turn radius mower.

If the rear wheel is a hub motor, then you have to use mechanical steering to point the front wheels.

Two wheel front drive will be plenty of traction. But you need special throttles, one on each side. Roll back to go forward, roll forward to go backwards. one forward one back will steer if the rear wheel casters.

Similar effect can be had with two normal throttles, and left and right brakes. Grab left brake, and right throttle, left turn.

It might be worth checking out Dr Bass's photo on the initial page. His trike uses skis on the front and a very powerful rear hub motor. Seems like a much simpler solution to riding in snow. On a trike, much of the weight is on the back wheel, depending, of course on where the batteries are placed. Sort of like a 3 wheeled VW Bug.
otherDoc

dogman dan said:

Torque vectoring would work best if the rear wheel is a larger caster. Then you have the same thing as a zero turn radius mower.

If the rear wheel is a hub motor, then you have to use mechanical steering to point the front wheels.

Two wheel front drive will be plenty of traction. But you need special throttles, one on each side. Roll back to go forward, roll forward to go backwards. one forward one back will steer if the rear wheel casters.

Similar effect can be had with two normal throttles, and left and right brakes. Grab left brake, and right throttle, left turn.

Click to expand...

I've been wanting to build a trike like this for years! Torque vectoring on two front hub motors, caster rear wheel. Do this and get rid of the pedals altogether, and you have eliminated what are the only complex parts of a tadpole trike: the steering linkage and running your drivetrain all the way from the front to the back.

Has anyone ever done this? This post here is the closest thing I can find on ES. In fact, any kind of dual hub motor tadpole trike seems very rare. I can only find pictures of one example.