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Updated: May 28, 2026
06:58
A Structured Rehabilitation Protocol for Improved Multifunctional Prosthetic Control: A Case Study
Published on: November 6, 2015
The role of feed-forward and feedback processes for closed-loop prosthesis control.
Ian Saunders1, Sethu Vijayakumar
1Institute of Perception, Action and Behaviour, School of Informatics, University of Edinburgh, UK. i.saunders@sms.ed.ac.uk
Journal of Neuroengineering and Rehabilitation
|October 29, 2011
Summary
Tactile feedback is crucial for object manipulation, especially when feed-forward control is uncertain. This study shows that while feed-forward control is robust, tactile feedback significantly enhances performance in prosthetic hands.
Area of Science:
- Robotics
- Neuroscience
- Biomechanics
Background:
- Object manipulation relies on both feed-forward and feed-back control mechanisms.
- Lack of tactile feedback in upper-limb prostheses may limit dexterity and grip control.
- Investigating whether prosthesis control deficits stem from feedback absence or feed-forward inadequacy.
Purpose of the Study:
- To determine the role of tactile feedback in object manipulation.
- To differentiate the contributions of feed-forward and feed-back control in grasping and lifting.
- To inform the design of advanced prosthetic hands.
Main Methods:
- Healthy subjects used a robotic hand to grasp and lift objects of varying weights.
- Experiments manipulated feed-forward and feed-back configurations.
- Recorded hand trajectories and force profiles under ideal, sensory-deprived, and uncertain conditions.
Main Results:
- Subjects maintained economical grasps even without visual or tactile feedback.
- Performance degraded significantly with feed-forward uncertainty when feedback was absent.
- Optimal performance was achieved with both visual and tactile feedback present.
Conclusions:
- Tactile feedback significantly enhances performance under feed-forward uncertainty.
- Feed-forward and feed-back mechanisms play complementary roles in object manipulation.
- Future prosthetic hands should address feed-forward control uncertainty.
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