Abstract
In developing the control system for the shoulder arm prosthesis, we have tried to answer the following fundamental question: How can we control the prosthesis to produce the intended movement by a natural physiological signal-giving motion?
First we define the intended movement to be a synergical movement to position the wrist. And in order to connect this movement with the physiological signal-giving motion of the shoulder, the analogue processing technique is adopted to detect the signal-giving motion. And the control-by-intention technique is newly proposed on the basis of the end point control technique in order to control the wrist positioning synergically. In the end point control technique, the control variable is the end point (an important position of the wrist in ADL), while in the control-by-intention it is an arbitrary direction vector. In order to obtain the synergical control of the prosthesis by the vector, the end point control technique is extended and the control-by-intention technique by the grid point vector has been introduced. Moreover the elbow declination control is introduced to make the movement more flexible by a tentative change of the content of grid points. As the result it is possible to make the prosthesis motion much more similar to the natural human movement in ADL.
