STATIC BALANCING OF A SIX-DEGREE-OF-FREEDOM PARALLEL MECHANISM WITH SIX TWO-LINK REVOLUTE LEGS

摘要

This paper addresses the static balancing of a six-degree-of-freedom parallel platform-type manipulator. The manipulator has six revolute legs, each leg consisting of two links that are connected by a revolute joint. Static balancing is defined as the weight of the links that does not produce any force at actuators for any configuration of the manipulator. Two methods are studied for the static balancing, using counterweights and using springs. In both methods, the resulting mechanism is fully compensated for gravity. Then, in the first method, the conditions for static balancing are expressed by a system of 11 equations with 15 linkage parameters, and the second by a system of 10 equations with 15 linkage parameters. Finally, examples are provided to demonstrate the developed method.