Analysis and control of 3R underactuated manipulator

In this paper, 3R underactuated Manipulator under gravity is to be considered. Dynamical behaviors under vibratory input to the first joint are analyzed via averaging analysis. It is clarified that dynamical stabilization onto a configuration other than the gravitational equilibriums can be realized using a kind of artifical potential prodused by vibratory input against gravity. And a method of shape control is also proposed.