Index Finger of a Human-Like Robotic Hand Using Thin Soft Muscles

This letter presents an index finger of human-like robotics hand which intends to closely replicate the human finger in terms of bones, ligaments, muscles, extensor mechanism, tendon, and its pulley system. We fabricated the muscles of the index finger using thin multifilament McKibben muscles that consist of three intrinsic and three extrinsic muscles with diameters of 1.3 mm and 4.0 mm, respectively. We present the fabrication method of the index finger and model it based on the Landsmeer Model I, II, and III. We validated the properties of our developed finger with the Landsmeer model for extension and flexion motion. Finally, we demonstrated the capabilities of the finger using motion capture, Tracker, to compare sweeps of the HR-hand finger with a cadaver finger motion for normal and finger deformity condition. Having McKibben muscles as the actuator that mimics the human muscle, one can better understand the human finger function and may use it for training and for modeling the human finger disorders.