Page 232 - Handbook of Biomechatronics

Upper-Limb Prosthetic Devices 229

History Lesson
In the 1920s the airplanes had Bowden cables (a form of EPP) so pilots can
“feel” where the flaps are, similar to how car drivers “feel” where the wheels
were with the unassisted passive steering. Later on, the modern airplanes use
mechatronic joysticks in a master slave topology to convey to the pilot as a
feedback the position of the flaps (see Fig. 28).

3.5.1.1 Enable Evolution of Older EPP With Mechatronics
In the 1970s the prosthetic industry took a turn from cineplasty and body-
powered prostheses to myoelectric control. The excitement of electronics
and the fact myoelectric control would eliminate the need for surgery
(cineplasty) or complicated harness and cables for body-powered played a
big role in that industry turn? What did we lose though? We lost proprio-
ception, the ability of the human to “feel” the state of the prosthesis subcon-
sciously, by using the remaining afferent (sensory) neural circuitry. This turn
maybe was not evident at that time because people substituted with visual
feedback or patients did not have the chance to evaluate and choose. It is
evident now, though. The lack of proprioception makes many-DoF control
more difficult or does not take the current prostheses closer to the “ideal”
state for upper-limb prostheses (see Fig. 29). The value of the EPP is shown

Fig. 28 Airplane’s evolution from Bowden cables to modern pilot joysticks.