Human–robot collision model with effective mass and manipulability for design of a spatial manipulator

As the use of service robots becomes more popular, many solutions to ensure human safety during human–robot collision have been proposed. In this paper, we address one of the most fundamental solutions to design an inherently safe robot manipulator. A collision model is developed to evaluate the collision safety of any spatial manipulator. Most collision studies have focused on collision analysis and safety evaluation, but not on the use of evaluation results to design a safer robot arm. Therefore, we propose a collision model that relates design parameters to collision safety by adopting effective mass and manipulability. The model was then simplified with several assumptions. Furthermore, experimental results from biomechanical literature were employed to describe a human–robot collision. The major advantage of this collision model is that it can be used to systemically determine the design parameters of a robot arm.