Tendon device for wearable muscle-assist robots

Tendon device for wearable robotic clothing to assist muscle strength

This technology is a mechanical mechanism that assists in the flexion and extension of human joints. It features a pair of wires and tendon modules with built-in individual torsion springs, enabling precise muscle strength assistance for each joint by calculating wire tension through torsion spring displacement measured by pulley encoders.

Conventional technology uses a single pulley for symmetrical joint movement, which leads to wire length imbalances. This makes it difficult to provide muscle support during irregular movements such as walking on stairs or inclines and limits control due to the inability to measure wire tension.

This technology applies independent tendon modules for each wire and installs torsion springs inside the pulleys to maintain wire tension and ensure back-drivability. It performs precise control by measuring human-robot interaction forces in real-time using the rotation angles calculated by pulley encoders and the spring constants. It can be applied to rehabilitation training, gait assistance, and medical/welfare services, improving precise control over joint movement and enhancing muscle strength support for daily activities.

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Key Features:

• A control unit that outputs control signals by calculating signals generated by the movement of the first and second wires in the first and second tendon modules, based on the tension of the first and second wires measured by the first and second pulley encoders.
• First and second wires that are fixed to the anterior and posterior sides of the user's joint, respectively, and move longitudinally according to the flexion and extension of the joint.
• A drive unit around which either the first or second wire is wound to assist the muscle strength of the agonist muscle during joint movement.
• A tendon device for wearable robotic clothing that provides muscle strength assistance, where the torsion of the second torsion spring maintains the tension of the second wire while providing back-drivability.

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This invention was developed with the support of the Ministry of Trade, Industry and Energy for the development of a wearable robotic system consisting of a 50W-class drive module for human muscle strength assistance and a human-robot muscle model-based control technique.