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Updated: Jul 1, 2026
09:41
Estimation of Contact Regions Between Hands and Objects During Human Multi-Digit Grasping
Published on: April 21, 2023
Functional workspace for precision manipulation between thumb and fingers in normal hands.
Li-Chieh Kuo1, Haw-Yen Chiu, Cheung-Wen Chang
1Department of Occupational Therapy, National Cheng Kung University, 1 University Road, Tainan 701, Taiwan, ROC. jkkuo@mail.ncku.edu.tw
Summary
This study defines and quantifies the human hand's functional workspace for precision grasp. Results establish objective metrics for hand function assessment and ergonomic design.
Area of Science:
- Biomechanics
- Human Factors Engineering
- Kinesiology
Background:
- Prehensile hand functions rely on thumb-finger interactions, crucial for daily activities.
- Maximal workspace is understood, but the functional workspace based on thumb-finger relationships remains largely unexplored.
Purpose of the Study:
- To define and quantitatively measure the functional workspace of the human hand during precision grasp.
- To establish a baseline for understanding the range of simultaneous thumb-tip and fingertip contact.
Main Methods:
- Recorded maximal motion trajectories of thumb-tip and fingertips from twenty subjects using a video-capture system.
- Calculated the functional workspace using numerical methods based on maximal workspace data.
- Determined the ratio of functional to maximal workspace for each finger.
Main Results:
- Quantified the functional workspace of the precision thumb-finger grasp.
- Calculated ratios of functional workspace to maximal workspace: Index (33.7%), Middle (27.1%), Ring (23.5%), Little (19.1%).
Conclusions:
- The study presents a novel quantitative method for measuring the functional workspace of the human hand.
- Findings may serve as objective standards for clinical applications, insurance claims, rehabilitation, and ergonomic design.
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