It is common to develop extensive dynamic models for new equipment early in the design stage. While dynamic characteristics are often determined from impulse, step, and sinusoidal inputs to the models, the actual response of the equipment will be a response to inputs made by the human using control levers, knobs and switches. The work described here is the use of a robot manipulator that allows the human to provide natural motion and force inputs to the simulated dynamic system and to use the response to evaluate the performance of the system and controls. A heavy lift assist device is used as the test system here, where an operator grasps handles attached to the lifting jaws, and uses a large partially powered mechanism to provide load support. The kinematic and dynamic model of this system are derived and programmed to provide the expected system output in response to human motion and force inputs. An industrial PUMA manipulator is outfitted with a lifting handle and programmed to follow the same motion as the simulated system would, given particular inputs. A force transducer measures the inputs from the human, and the operator can assess system performance using both the response data and an evaluation.