AN OPTIMAL FORCE DISTRIBUTION SCHEME FOR COOPERATING MULTIPLE ROBOT MANIPULATORS

Abstract

In this paper, we suggest an optimal force distribution scheme by weak point force minimization and we also present an efficient method to solve the problem. The concept of a weak point is a generalized one which is applicable to any points of interest, as well as joints or contact points between end-effectors and an object. The problem is formulated by a quadratic objective function of the forces exerted at weak points subject to the linear equality and inequality constraints, and its optimal solution is obtained by an efficient method. As regards the solution of the problem, the original problem is reformulated to a reduced order dual problem after the equality constraints are eliminated by force decomposition. Then an optimal solution is obtained by a linear complementary pivoting method together with a cutting plane method proposed in this paper to accommodate inequality constraints. The proposed method is applicable to diverse areas such as a fragile and long object, weakly connected assembly parts, and weakly combined joints in cooperating multiple robot manipulators. A similar problem can be formulated for a multi-legged vehicle or a multi-fingered hand.