The field of prosthetics has experienced great achievements in recent years. The development of controllable robotic arms and hands has had a significant impact on the quality of life for amputees. In prosthetic design, the new fields of mechatronics and bioengineering have combined to produce some very innovative solutions. One of the more recent developments has been the robotic-controlled ankle. In earlier prosthetic designs, the ankle mechanism was modeled using a simple cantilever beam made of carbon composite materials.