When studying brain activity in animals, scientists try to intrude as little as possible in their daily activities. Ideally, they would like the animal to have free range of motion, but this is rather difficult while attached to a EEG. What is needed is a device that allows faint signals to be measured while the animal is freely moving in their habitat.
Hypnion Inc. brought this problem to my current employer and asked us to help solve it. My team and I produced an ultra low friction commutator that could achieve the signal requirements they needed, while dramatically reducing the disturbance to the small rodents. We designed and built a prototype which was then manufactured in the hundreds.