A technique for the robot trajectory planning is proposed.The technique mainly consists in controlling a manipulator by assigning not only the way points on the path but also the geometrical tangent of the desired path shape at each of those points.This is achieved by assigning to the control system not only the joint variables { q i } , but also the vector values { q ? i } of the velocities that the joints must have when the end-effector passes through each of those trajectory points.In this way if a path is defined by a same number of points, the proposed technique permits to achieve more accurate paths than those obtained by a traditional point to point technique.Finally, some examples are presented making comparisons on same trajectories assigned by different techniques and also an example of a elaborate surface. Highlights? A technique for the robot trajectory planning is proposed. ? The trajectory is obtained by "envelope of tangents". ? The joints velocities vector values at each of the trajectory points are assigned. ? The end-effector leaves each assigned point moving along the tangent to the path. ? The end-effector reaches the next assigned point moving along the tangent to the path. ? Test results show that the proposed technique permits to achieve more accurate paths.