Acceleration-based transparency control framework for wearable robots

To render a wearable robot imperceptible to a user is a very challenging control task. The constant and intrinsic interaction between robot and human, and person-dependent behaviours are the main difficulties when designing such cooperative control. In this contribution we introduce and discuss a novel and promising transparency control framework. The foundation of the framework is to measure the acceleration of the human limbs and to exploit this measurement to generate feedforward control commands by using a rigid body model of the robot. The framework includes also an acceleration feedback controller and a state estimator to enhance the overall performance. We present a simplified stability analysis with different feedback controllers and preliminary experimental data that demonstrate the potential of the proposed method in reducing interaction forces and mimicking human motions.