Crossing Biomimetic Kinematic Pair

Aligns with finger joint motion

Based on medical imaging, an equivalent instantaneous center of rotation model is built so the exoskeleton joint follows the finger's true rolling-sliding motion, reducing misalignment and pressure concentration.

Zhang, Peng · Ge, Shuyuan

Biomimetics 2025

Specifications

Reduction in mean pressure at MCP and PIP

{'zh': '15-25', 'en': '15-25'} %

Reduction in peak pressure at MCP and PIP

{'zh': '20-30', 'en': '20-30'} %

Advantages

Tracks finger motion accurately

Using an equivalent center of rotation model, the crossing kinematic pairs enable the exoskeleton fingertip trajectories to match physiological trajectories with significantly reduced RMSE, demonstrating improved kinematic alignment over fixed-axis assumptions.

Peak pressure drops by 20-30%

Peak pressure at MCP and PIP is reduced by approximately 20-30% with more uniform distribution, alleviating pressure hotspots and reducing risk of soft tissue injury.

Drives ten DOFs across fingers

The three-loop ten-linkage exoskeleton provides dual DOFs per finger (flexion-extension and abduction-adduction, 10 DOFs in total), accommodating complex grasping movements.

Applications

• Hand rehabilitation exoskeleton：Replaces fixed-axis hinges to eliminate misalignment and pressure sores caused by center of rotation drift.
• Anthropomorphic robotic hand：Uses crossing biomimetic joints to mimic human finger rolling-sliding motion.
• Wearable rehabilitation device：More uniform pressure distribution enables long-term wear without soft tissue injury.