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Updated: Jul 15, 2026
09:36
Measurement of Spatial Stability in Precision Grip
Published on: June 4, 2020
Perceived and actual grasp forces on cylindrical handles.
David J Cochran1, Yuxiang Chen, Xuedong Ding
1Department of Industrial and Management Systems Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588-0518, USA. dcochran@unlnotes.unl.edu
Human Factors
|April 24, 2007
Summary
Grasp force perception is linear up to 80% of maximum voluntary contraction (MVC) on cylindrical handles. Beyond 80%, the relationship between perceived and actual grasp force becomes quadratic, requiring a different model for accurate estimation.
Area of Science:
- Ergonomics and Human Factors
- Biomechanics
- Occupational Health
Background:
- Musculoskeletal disorders are linked to forceful workplace exertions.
- Accurate measurement of exertion forces is challenging.
- Estimates often rely on perceived force relative to maximum voluntary contraction (MVC).
Purpose of the Study:
- To compare actual grasp force with perceived grasp force on cylindrical handles.
- To establish a functional relationship between perceived and actual grasp force as a percentage of MVC.
- To inform estimations of grip exertion in occupational settings.
Main Methods:
- Participants exerted grasp forces on five different cylindrical handle sizes.
- Grip pressure was measured at 16 locations on the hand.
- Participants perceived and exerted specific percentages of their MVC in 10% increments.
Main Results:
- A linear relationship was observed between perceived and actual grasp force up to approximately 80% of perceived MVC.
- Above 80% of perceived MVC, the relationship transitioned to quadratic.
- A piecewise regression model accurately described the entire range of perceived grasp forces.
Conclusions:
- Grasp force is linear and consistent up to 80% of perceived maximum voluntary contraction (MVC).
- The relationship between perceived and actual grasp force becomes quadratic beyond 80% MVC.
- Practitioners can apply a linear model for perceived MVC up to 80% and a quadratic model for higher percentages when assessing grip on cylindrical handles.
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