Tendon-Driven Actuation Module for Robotic Hands (UCLA Case No. 2015-071)

Summary:

UCLA researchers in the Department of Mechanical Engineering have developed a modular actuation system that can control robotic manipulators of the same size and form as the human hand with unprecedented speed, strength, and precision.

Background:

The design of humanoid robotic hands is limited by their small volume constraints. To achieve a desirable combination of dexterity and strength, many robotic hands use an "extrinsic" actuation scheme akin to the human hand, wherein muscles (actuators) located in the forearm control the fingers via tendons. Many robotic systems have been developed based on this tendon (i.e. cable)-driven design concept, but existing robotic technologies lack the collective performance of the human hand in terms of speed, strength, and precision of control. There remains an unmet need for an improved design of compact robotic manipulators and actuation schemes.

Innovation:

UCLA researchers in the UCLA Biomechatronics Lab led by Dr. Veronica J. Santos have developed a compact actuation module that can deliver fast, forceful, high-precision control of any tendon-driven robotic manipulator. The design is based on a rotary motor unit that can exert either uni- or bi-directional ("push-pull") control of any tendon-driven rotational joint, thereby enabling independent, high-performance control of each individual active degree of freedom in a robotic hand, including a palmar flexion degree of freedom. This design overcomes the limited speed and strength of existing actuation modules used in robotic technologies.

Demonstration Videos:

Giving robots and prostheses the human touch - Science Nation

Using Robotics for Assistive Devices | Mission Unstoppable

Patents:

10,029,364
10,899,003

Potential Applications:

• Robotic prosthetic hands
• Robotic manipulators
• For tele-operated systems: e.g. robotic telesurgery, bomb disarmament, brain-controlled robotic devices for neuro-rehabilitation
• For automated robotic systems: e.g. mobile housekeeping & courier robots
• Robotics & machine learning research platforms

Advantages:

• Speed: human-like speeds without performance degradation
• Strength: dynamic operating range
• Performance & Precision Control: cable pre-tensioning mechanism and integrated load cell
• Simple hardware requirements: bi-directional motor action
• Compliance: actuation passive compliance for unexpected loads or impacts during operation
• Versatility: compatible with a variety of robotic manipulator designs
• Modularity & Scalability: various arrangements of robotic fingers and actuation units
• Bio-inspired Design: compatible with human form factor for robotic and prosthetic applications
• Adaptability: compatible with a variety of end effectors and sensors

State of Development:

This technology has been prototyped and extensively tested by the research group of Dr. Veronica J. Santos in the UCLA Biomechatronics Laboratory. The test platform is comprised of the novel actuation unit in conjunction with a robotic finger.