Abstract
It is important to save the dissipated energy even of a manipulators for improving the environment of the earth which is warmed up by CO2 gas emitted from thermal power plants. Hence, this paper describes an optimal path and operating time which minimize the dissipated energy in PTP motions of a vertically articulated manipulators. A globally optimal path is roughly estimated so that the heavier link is accelerated toward gravitational direction and decelerated toward anti-gravitation. This proposed path is used as a starting function of the iteration method solving a non-linear two-point boundary-value problem. In order to avoid collision with the obstacle such as a desk laying a handled material, the obtained optimal path is modified by an optimal control theory with state constraints.
The simulation results show that a proposed optimal path can reduce the dissipated energy to 1/14 -1/30 compared with conventional path when the operating time is selected so as to be optimal.
