Design and control of a three‐degrees‐of‐freedom, in‐parallel, actuated manipulator

The mechanics, design, and control of a 3–degrees‐of‐freedom, in‐parallel, pneumatically actuated manipulator are presented. The manipulator consists of two platforms connected by three serial chains. The kinematic design is such that the three relative degrees of freedom between the two plates allow the manipulator to accomodate uncertainties and sustain impacts while contacting and interacting with unknown environments. In particular, the manipulator is naturally compliant in translation along the approach direction as well as in rotations about axes perpendicular to the approach direction, while it is stiff in other directions. In this article, an overview of the manipulator kinematics, a description of the manipulator system and the associated hardware, and experimental results on the dynamic behavior of a prototype are presented. © 1994 John Wiley & Sons, Inc.