A three-dimensional anthropometric solid model of the hand based on landmark measurements

Area of Science:

• Ergonomics
• Human Factors Engineering
• Anthropometry

Background:

• Existing hand anthropometry data often uses outstretched hand measurements, limiting its application to functional gripping postures.
• Accurate hand anthropometry is crucial for the ergonomic design of hand tools to ensure user comfort and safety.

Purpose of the Study:

• To develop a representative and scalable 3-D hand model.
• To aid in the ergonomic design of hand tools by providing accurate hand models for gripping postures.
• To create a valuable resource for 3-D software drawing packages.

Main Methods:

• Digitized 66 landmarks on the palmar surface of 100 subjects' right hands across four functional postures.
• Developed 3-D surface models representing the mean, 25th, and 75th percentile hands.
• Validated the model by comparing hand length and breadth measurements against digitized data.

Main Results:

• The 3-D hand model demonstrated good agreement with digitized hand measurements.
• Root mean square differences for hand length were 11.4 mm (25th%), 3.2 mm (50th%), and 8.9 mm (75th%).
• Root mean square differences for hand breadth were 2.0 mm (25th%), 0.4 mm (50th%), and 1.4 mm (75%).

Conclusions:

• The developed 3-D hand model effectively represents hands in functional gripping postures.
• This research provides improved hand anthropometry reference values for general population tool design.
• The model facilitates enhanced ergonomic hand tool design through accurate, posture-specific data.