To　comply　with　the　process　of　a　space　robot　capturing　a　spacecraft　and　the　subsequent　auxiliary　docking　operation，　precise　control　of　the　output　force　and　position　of　the　spacecraft　docking　device　was　studied　herein.　A　spring　damper　buffer　device　was　added　between　the　joint　motor　and　manipulator　to　prevent　the　joint　from　being　damaged　under　the　huge　impact　force　generated　during　contact　and　impact.　First，　by　combining　Newton＇s　third　law，　velocity　constraints　of　the　capture　points，　and　closed-chain　system　geometric　constraints，　a　dynamic　model　of　the　hybrid　system　after　capture　was　obtained，　and　the　impact　effect　and　force　were　estimated　based　on　momentum　conservation.　Then，　the　impedance　model　during　docking　was　established　through　the　kinematics　of　the　spacecraft　docking　device　relative　to　the　base　coordinate　system.　Subsequently，　a　robust　adaptive-double-layer　sliding-mode　control　strategy　was　developed.　Combined　with　impedance　control，　this　strategy　employed　a　force　load　servo　control　system　to　accurately　control　the　position　and　output　force　of　the　docking　device　to　reduce　the　impact　force　during　contact　and　impact.　The　control　strategy　featured　a　double-layer　sliding-mode　structure，　with　the　first　layer　ensuring　convergence　of　the　hybrid　system　in　finite　time　and　the　second　layer　being　used　to　solve　the　high-gain　problem　of　the　controller.　Finally，　the　stability　of　the　system　was　proved　using　the　Lyapunov　theorem，　and　the　effectiveness　of　the　proposed　strategy　was　verified　through　a　numerical　simulation.　The　simulation　results　indicate　that　the　buffer　device　can　reduce　the　impact　force　by　46.78%　of　the　maximum　at　the　given　velocities.　Moreover，　the　control　accuracy　of　the　output　force　is　better　than　0.5　N，　while　the　accuracies　of　the　position　and　attitude　are　better　than　10-3　m　and　0.5°，　respectively.　©　2023　Chinese　Academy　of　Sciences.　All　rights　reserved.