Adaptive Control of a Wheelchair-Pushing Holonomic Robot Subject to Input Constraints

摘要

In our earlier work, we proposed a synergistic design and control strategy to enable a holonomic mobile robot transport wheelchair bound residents in long-term-care facilities. Several simplifying assumptions were made and an adaptive control framework was proposed for wheelchair trajectory tracking. We remove some of the limiting assumptions by considering actuator saturation and actuator dynamics in this paper. We modify the adaptive controller and show that asymptotic trajectory tracking can be achieved provided that the reference trajectory does not result in complete loss of control authority. In the absence of control authority, we suspend trajectory tracking to maintain stability and revert to asymptotic trajectory tracking when control authority is regained. Although we focus on an application for long-term-care facilities, the technology being developed will find diverse applications such as autonomous transportation of hazardous materials.