A robust tracking controller for rigid-link electrically driven (RLED) robot manipulators operating in free-space or under motion constraints is introduced. Using models of the robot dynamics and environmental constraints, a dynamic model with decoupled position and force degrees of freedom is obtained for the mechanical subsystem with respect to a set of task-space coordinates. A robust tracking control is then formulated for the decoupled manipulator dynamics and the electrical actuator dynamics, which yields a global uniform ultimate bounded (GUUB) stability result for the position and velocity tracking error. The controller is robust with respect to parametric uncertainties and additive bounded disturbances in the RLED dynamic model. The controller requires measurement of the robot link positions, link velocities, and motor armature currents.