A few years ago, someone on the EV List posted about Electric Barstool Racing. 

As you can see, the barstool is a little the worse for wear, but at least it does now have a purpose in life! 
 

The barstool uses two motors, one driving each of the two rear wheels via a belt drive, made out of Mini fan belts. At the moment, there is no gearing (it's direct drive), so starting torque is a problem. Top speed would be pretty horrific too, so I will need to put some gear reduction in to avoid burning out the motors, and getting booked for speeding!

Motors - these are Mini dynamos, which have separate field and armature windings. 

This allows them to be used as motors. 

I have modified the field windings so that I can reverse the current through them, this makes the motor turn backwards.... 
 

The two large silver-coloured blocks near the seat are the controllers - these are two huge darlington transistor arrays, which can switch up to 160 amps each. They have built-in diodes too, just perfect for inductive loads ... I ripped them out of a dead UPS we had in work. 

The Plan is to have a small PIC feeding PWM control signals to these darlington arrays, to control the power to the motors. The PIC will also control two relays which will reverse the field current to control the direction of each motor. A PC joystick will provide user input to the PIC, so it'll just be "point 'n' shoot" ! 

June 99....

I have recently upgraded the Barstool, it now has two car batteries giving 24 volts of raw power, a 200 amp contactor, 100 amp fuses for each battery, and an industrial machine style emergency stop control box! I've also found a footswitch assembly, which lurked in my cupboard for 7 years.....

With 24 volts buzzing through both motors, it does actually move, even with me sitting on top of it!

But, the motors are getting hot - it'll be letting the smoke out soon - so the next upgrades will be:

1. Add a huge blower to blast air through the motors

2. Change the gearing, so the motors don't have such a hard time !