One aim of controlling a manipulator robot is to maximize its performances such as accuracy, speed, time etc…. However, limiting the power of actuators causes a limitation of their generalized accelerations and velocities; this is due to the high inertial forces, which create dangerous voltages at the machines elements. This paper propose an algorithm to solve the problem of maximizing the manipulator performances considering that the end-effector position and orientation is characterized by a 6x1 vector i.e., six degrees of freedom; moreover, the need to move the end-effector from the start position to the target with a minimum time, without violating its boundaries. The presented solution is well suited to this context. It is optimal with respect to time constraints, and it allows a direct calculation.