Adaptive under-actuated anthropomorphic hand:
People involved:
- Mahmoud Tavakoli
- Anibal T De Almeida
ISR-Softhand is a novel under-actuated self contained anthropomorphic robotic hand which takes advantage of elastic joints and soft pads. The integrated compliance in the hand’s joint allows for a very good adaptability to a wide range of objects. It can achieve the top ten grasps with highest frequency of usage by humans, with only three actuators.
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-33-100-1.jpg)
Bones and joints of the human hand, DIP – Distal Interphalangeal joint; PIP – Proximal Interphalangeal joint; IP – Interphalangeal joint; MCP – Metacarpophalangeal joint; CMC – Carpo-Metacarpal joint.
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-32-100-1.jpg)
Conceptual design of the Softhand: Each finger is composed of MCP and PIP joints and does not include the DIP joint. The thumb is composed of CMC and MCP joints. Except the non/actuated thumb abduction/adduction joint, all other joints are fabricated with elastic materials.
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-58-100.jpg)
The three actuators drive flexion of the thumb, flexion of the index and flexion of the remaining 3 fingers. The thumb abduction/adduction is performed manually.
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-30-100-1.jpg)
Fabrication method: The 3D printed index finger before casting the Urethane rubber (up), the finger after casting(down).
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-57-100-1.jpg)
Routing of the tendons for all five fingers.
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-34-100.jpg)
Forces applied to the fingers in a tip pinch.
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-55-100-1.jpg)
Large diamete, lateral pinch, medium wrap and sphere 3 finger grasps performed by the ISR-Softhand.
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-54-100-1.jpg)
Tip pinch grasp was succesfully performed for grasping several objects.
![](https://spm.isr.uc.pt/wp-content/uploads/2019/09/Asset-53-100.jpg)
The initial synergy of the hand which could perform seven out of the top ten grasps, has only an open and a close position.
Adaptive under-actuated anthropomorphic hand: ISR-SoftHand.
M. Tavakoli and A. T. de Almeida, “Adaptive under-actuated anthropomorphic hand: ISR-SoftHand,” 2014 IEEE/RSJ International Conference on Intelligent Robots and Systems, Chicago, IL, 2014, pp. 1629-1634. doi: 10.1109/IROS.2014.6942773