Joint mechanism

Biomimetic Joint Mechanism Combining Tendon Tension and String Resilience

This technology is a biomimetic joint mechanism that performs bending motions using tendon tension and returns to its initial position using the resilience of a string set. It is designed to allow joint rotation without bearings by connecting multiple bodies with strings at set intervals.

Existing robot joints suffer from mechanical wear, discomfort due to heavy components, a lack of biomimetic structure, limited shock absorption, and increased control complexity.

This technology constructs joints by connecting bodies with tendons and multiple strings, eliminating direct contact between the bodies. Bending is controlled via tendon tension, while the tensile elasticity of the strings provides natural restoration. By asymmetrically adjusting the tension of certain strings, the range of motion during rotation can be variably limited to enhance gripping force. Applicable to wearable robots, prosthetic hands, and collaborative robots, it enables bearing-free joint operation while improving durability and wearer comfort.

‍

‍

Key Features:

• A first body equipped with a fastening part where the tendon is secured, spaced apart from the center toward the top in the height direction
• A second body connected to the first body by a first string set and equipped with a first pulley for housing the tendon
• A first tendon guide provided between the fastening part and the first pulley to guide the tendon downward
• A first string set consisting of strings 1-1 through 1-4 that connect the opposing wings of the first and second bodies

‍

This invention was developed with support from the Ministry of Science and ICT for the development of biomimetic bionic arm mechanisms.