 To mimic the knee's functionality during gait, microprocessor-controlled knee joints have been developed that control the flexion of the knee.Some examples are Otto Bock’s C-leg, introduced in 1997, Ossur's Rheo Knee, released in 2005, the Power Knee by Ossur, introduced in 2006, the Plié Knee from Freedom Innovations and DAW Industries’ Self Learning Knee (SLK).The idea was originally developed by Kelly James, a Canadian engineer, at the University of Alberta.