Reel-Based Tension Control of Tethered Space Robots

This article elaborates on the tension control design of tethered space robots for debris removal. The novel approach is to change the tether natural length via a reel. With only the tension sensing, we leverage a Kalman filter and a recursive least-squares algorithm to estimate the actual length and the debris mass, which are fed back to a model-predictive controller to generate the optimal tangential velocity of the reel. Simulations show that the stiff tether exhibits better tension-tracking performance which is robust to the tumbling debris.