Precision Grasp Using an Arm-Hand System as a Hybrid Parallel-Serial System: A Novel Inverse Kinematics Solution

In this letter, we present a novel inverse kinematics (IK) solution for robotic arm-hand system to achieve precision grasp. This problem is kinematically over-constrained and address the issue solve problem, propose new approach with three key insights. First, human-inspired thumb-first strategy consider one finger of hand as “thumb” narrow down search space increase success rate our algorithm. Second, formulate arm-thumb serial chain closed such that entire controlled hybrid parallel-serial system. The closed-chain formulation simplifies task hierarchy Third, attach virtual revolute joint thumb's tip its rotation axis aligning contact normal will embody functional redundancy. By selecting joints including added active chain, system's self-motion (i.e., palm pose) redundancy can be directly without using null projection. provides possibility control systems. Simulation results demonstrate advantages superior performance proposed achieving grasp compared other classical approaches.