Revisiting the Effect of Velocity on Human Force Control

Human-robot collaborative systems (HRCS) have the potential to dramatically change many aspects of surgery, manufacturing, hazardous-material handling, and other dextrous tasks. We are particularly interested in precise manipulation tasks, which are typically performed under an admittance-control regime, where the controlled velocity is proportional to the user-applied force. During precise fast movements, there is a noticeable degradation in control precision, and prior results have indicated that system velocity, and not system admittance, is the factor that is correlated with force-control precision. In this paper, we report evidence that system admittance is more important than velocity in determining the user’s ability to control force, and we provide an explanation as to why prior results might have indicated otherwise.