Design and Analysis of a Grasping Mechanism with an Actuated Palm for On-Orbit Servicing

To address the inability of existing space grasping mechanisms to adapt to the varying shapes and sizes of space objects, we propose a novel three-fingered space robotic hand composed of an actuated palm and deployable fingers with the aim of successfully grasping a wider variety of space objects. We begin by elaborating on the design concept of the robotic hand. Compared to traditional robotic palms, the actuated palm possesses deployment and metamorphic functions, allowing it to adjust its dimensions to actively adapt to different items. The modular deployable fingers are designed based on a parallel scissor mechanism featuring folding and deployment functions. Next, a kinematic analysis and performance evaluation are performed. The force closure and contact force distribution are also analyzed. After that, a physical prototype is fabricated, and basic motion and grasping tests are performed. The proposed three-fingered robotic hand exhibits excellent adaptability. Finally, the design trade-offs are discussed, along with an analysis of the model’s limitations and future prospects, and it is demonstrated that the proposed novel robotic hand has broad application prospects in future on-orbit missions.