A bio-inspired dual-mode gripper using for climbing robot in microgravity

Reliable locomotion on spacecraft exteriors is fundamental to autonomous On-Orbit Servicing (OOS), but it remains a significant challenge due to the mechanical heterogeneity of surfaces, such as rigid metallic panels and compliant Multilayer Insulation (MLI). This paper presents SPACE-1, a bio-inspired quadrupedal climbing robot designed to achieve stable traversal across these diverse substrates in microgravity. A novel dual-mode gripper integrating colloid-based dry adhesion and spine penetration is designed within a unified single-actuator architecture. To eliminate the need for manual mode switching, a kinematically optimized five-bar linkage is developed to internalize the switching logic into a deterministic interaction trajectory. This mechanism ensures an oblique insertion path to anchor on soft MLI without causing material bunching, and a nearly vertical separation path to minimize detachment induced disturbances on rigid surfaces. Furthermore, a momentum-aware trajectory optimization framework based on seventh-order Bézier curves is implemented to suppress reactive impulses during dynamic gait transitions. Experimental results in simulated microgravity demonstrate successful navigation on both rigid and soft MLI surfaces, achieving climbing speeds of 5.3 mm/s and 2.2 mm/s, respectively. The results confirm SPACE-1’s potential for future autonomous spacecraft inspection, maintenance, and assembly operations.