Human-Coordinated Control of Two-Wheeled Robot with Elastic Handle

The electronic commerce (EC) market in the BtoC industry has grown rapidly in recent years. Consequently, the volume of parcel delivery services is also rising, and the physical burden on the delivery staff is increasing. Therefore, this study aims to develop a new transport support system that enhances operability and followability. In this method, an elastic handle is attached to a two-wheeled robot. The elastic handle reduces the turning radius, improves the tracking performance, and minimizes operational discomfort as it deforms to follow the direction the user pulls. However, the elasticity of the handle may cause the robot's pitch angle to tilt excessively, or the handle may vibrate owing to elasticity, leading to reduced operability. This study implements stabilization control in the translational and pitch angle directions to address these issues, considering disturbances and using a Lyapunov controller. In the turning direction, turning angle control is implemented using load-side acceleration control with the handle side as the load. The effects of the elastic handle and control system were verified through simulations. Verification results confirmed that the system can follow human operations and reduce human effort while stabilizing the robot body.