“…This has an important drawback, leading to a weak stability margin for grasping. To tackle this problem, the minimization function , (5), is modified by introducing weight coefficients as follows: (13) This function can be also written as follows: (14) where is a diagonal matrix, defined as: , , , . Proposition 1: The optimal forces for the minimization of function , defined by equation 13, under the constraints imposed by (1), are given by the following equation: (15) or equivalently (16) where is a weighted pseudoinverse of matrix , with:…”