This paper deals with the problem of the dynamic stress optimisation for manipulator robots. The maximum dynamic stress search is a challenging problem, insofar the dynamic stresses change in a very complex manner and they are strongly influenced by the payload, internal parameters of the robot, and instantaneous values of the articular variables (positions, velocities, and accelerations). This problem is solved using a hybrid simplex-genetic algorithm. This algorithm allows solving the dilemma of exploration vs. exploitation in the search space. A simulation study shows the greater performance of the proposed approach as compared to a classical approach of the configuration space inverse sweeping.