Instead of having our own STM32F4 micro-controller circuit, this new design uses the Crazyflie 2.0 nano drone from Bitcraze. The drone is plugged on the O'PAVES board using its extension port. This means that the board is really easy to build (no SMT soldering). Here's a picture of the first iteration of this new design:
You can also see that the motor is different. The pervious version used a single motor with the two rear wheels fixed on the same shaft. This means the two wheels have to turn at the same speed which results it poor cornering. That's why cars have differential. It's difficult to have a differential on such a small car, it would increase a lot the complexity of the design. For this new version we use a dual motor gear box, which means that each wheel has it's own motor and can turn at a different speed than the other. This improved a lot the cornering as you can see here:
The dual motor configuration might also allow us to implement active differential, where we can increase the power in one of the two motors to make the car turn tighter.