Compliance Flatness Based Control of a Collaborative Upper-Limb Exoskeleton Robot

This paper focuses on two challenges when developing the Smart Robotic Exoskeleton (SREx), a new exoskeleton robot that collaborates with individuals with Upper Limb dys-functions. The first challenge is estimating the wearer’s desired intended motion (DIM) for the robot accurately. The second challenge is implementing a robust control strategy for the SREx, which entails transforming variables to achieve the triangular flat canonical normal form (TCNF) for nonlinear dynamic systems with the flatness geometric property. Damped Least Square (DLS) is used in the proposed geometrical transformation-based control strategy to link the estimated DIM to the flatness-compliant control, allowing the SREx to track the wearer’s motion easily. Experiments and comparative studies are presented to show the effectiveness of the proposed control scheme.