2017 Formula SAE Events

FSAE Lincoln Nebraska

Wisconsin’s FSAE Team competing in Lincoln

Most performance differentials are severely handicapped relative to the potential of the “differential” in the University of Wisconsin’s Formula SAE car.

The typical racing differentials work by using a clutch to clamp the left halfshaft to the right halfshaft and forcing the two tires to rotate together.  However, the tires on the outside of the turn (right tires in a left turn) needs to travel a longer distance around a corner than the tires on the inside of the turn.  Therefore, they naturally want to rotate at different speeds.  Using a clutch to minimize the wheel speed difference across an axle is good in a straight line but means you will compromise one or both of the tires’ grip in a corner.

Wisconsin’s FSAE team built a racecar with one electric motor per rear wheel.  By having independent control of each of the wheels, Nebraska can drive each of the wheels to its individually appropriate slip level.  Not only can this optimize acceleration but it has the potential to make the car more closely follow the driver’s steering request.  Similar to a driving a military tank or a Bobcat brand skid steer loader, send more torque to the right side and you will turn left and vice versa.  They have broken the constraints associated with typical racing differentials.

Wisconsin’s team did a tremendous job in bringing this and many other technologies to reality.

Electron Speed plays a role in the FSAE competition by identifying and rewarding teams that are doing the best job in bringing the next generation of engineers and business leaders up to speed.  With our background in performance chassis controls, it was easy to see the value in Wisconsin’s educational experiment.

For more on Wisconsin’s FSAE effort, see their page.
For more on steering a tank, visit Wikipedia.
For more on Torque Vectoring, visit Wikipedia.
For more on Skid Steer, visit Wikipedia.