2019 Volume 55 Issue 5 Pages 353-361
For a control system operated by a human, human assist control to avoid accidents attracts much attention in recent years. In this paper, we propose a novel definition of a control barrier function and a human assist control law with the proposed control barrier function. This paper proves that the proposed human assist control guarantees the safety of the control system under the human operation. Moreover, the paper shows that the control is the minimum of all safe inputs and a continuous function of both state and human inputs. The effectiveness of the proposed method is confirmed by computer simulation and experiments of a four-wheeled mobile robot.