Drive force optimization for a redundant parallel machine

Redundant actuation can effectively eliminate singularities in the task space of a parallel manipulator,but the drive force distribution is not unique because of the redundant actuation.This paper presents an analysis of the redundant actuation of a 4 degree of freedom parallel machine.An inverse kinematic analysis was used to calculate the partial angular velocity matrix and the partial velocity matrix for each link to calculate the resultant force and torque on each link.The inverse dynamics equation was then developed based on the virtual work principle and then linearized.The drive force was then optimized using force optimization and energy optimization due to the redundant actuation.The force optimization method is more efficient while the energy optimization method gives a lower maximum drive force.This dynamic model can be used to identity the dynamic parameters and for dynamic control.