Compared　with　the　ground　environment，the　robot　system　exposed　to　cosmic　rays　in　space　environment　is　more　susceptible　to　external　interference，and　the　system　parameter　changes　such　as　mass　and　inertia　caused　by　difficult　maintenance　and　fuel　consumption　make　it　more　prone　to　system　uncertainty.　Aiming　at　the　problems　of　system　uncertainty　and　external　interference　in　a　floating　space　robot　system　with　uncontrolled　carrier　position，a　trajectory　tracking　control　method　based　on　variable　universe　fuzzy　control　is　proposed.　On　the　basis　of　calculating　torque　controller　to　solve　the　nominal　system　control　torque，the　variable　universe　adaptive　fuzzy　controller　is　used　to　compensate　the　errors　caused　by　the　system　uncertainty　and　external　interference.　The　real-time　change　of　the　scope　of　the　variable　domain　makes　the　fuzzy　controller　applicable　to　different　error　ranges　at　different　time，thus　effectively　improving　the　response　speed　of　the　system　and　reducing　the　steady-state　tracking　error　of　the　system.　Finally，the　stability　of　the　control　scheme　is　proved　by　Lyapunov　method，and　the　effectiveness　of　the　control　method　is　proved　by　numerical　simulation.　©　2024　Nanjing　University　of　Aeronautics　an　Astronautics.　All　rights　reserved.