A Low-Cost Compliant Gripper Using Cooperative Mini-Delta Robots for Dexterous Manipulation

Traditional parallel-jaw grippers are insufficient for delicate object manipulation due to their stiffness and lack of dexterity. Other dexterous robotic hands often have bulky fingers; rely on complex time-varying cable drives; or are prohibitively expensive. In this paper; we introduce a novel low-cost compliant gripper with two centimeter-scaled 3-DOF delta robots using off-the-shelf linear actuators and 3D-printed soft materials. To model the kinematics of delta robots with soft compliant links; which diverge from typical rigid links; we train neural networks using a perception system. Furthermore; we analyze the delta robot's force profile by varying the starting position in its workspace and measuring the resulting force from a push action. Finally; we demonstrate the compliance and dexterity of our gripper through six dexterous manipulation tasks involving small and delicate objects. Thus; we present the groundwork for creating modular multi-fingered hands that can execute precise and low-inertia manipulations.