Mobile Assistive Robot with Shared Control

The rapidly aging population and the existence of a large number of people with different kinds of disabilities pose a great challenge to engineers and researchers to design and build suitable and practical healthcare robotic systems. There are many applications and potential for assistive robotic systems in the area of healthcare. In this thesis, a prototype of a novel mobile assistive robot for senior and disabled people has been developed to help the group transport heavy objects in their daily life. Several technical problems related to the design of the system are addressed and solved. In this robot prototype, a haptic device is used as the input interface to build the haptic interaction channel and compensate for the loss of visual or auditory capabilities in the target user. A nonlinear tracking controller is designed for the robot to follow the user. An obstacle avoidance controller is developed based on the deformable virtual zone (DVZ) principle, in order for the robot to avoid obstacles. A shared control problem is also studied in this thesis. Since the user may not have a normal level of mobility and cognitive capabilities, a stable and optimal adaptive servo-level shared control algorithm is applied to properly allocate the input authority between the human and the artificial intelligence when the robot encounters obstacles. Extensive experiments have been conducted to validate the control algorithms developed. The results demonstrate that in a cluster environment, the proposed robot can smoothly track the user.