Efficient parallel algorithms for robot forward dynamics computation

Abstract

Computing the robot forward dynamics is important for real-time computer simulation of robot arm motion. Two efficient parallel algorithms for computing the forward dynamics for robot arm simulation were developed to be implemented on an SIMD computer with n processors, where n is the number of degrees-of-freedom of the manipulator. The first parallel algorithm, based on the Composite Rigid-Body method, generates the inertia matrix using the parallel Newton-Euler algorithm, the parallel linear recurrence algorithm, and the row-sweep algorithm, and then inverts the inertia matrix to obtain the joint acceleration vector desired at time t. The second parallel algorithm, based on the conjugate gradient method, computes the joint accelerations with a time complexity of O(n) for multiplication operation and O(nlogn) for addition operation. The proposed parallel computation results are compared with the existing methods.