Automated pressure map segmentation for quantifying phalangeal kinetics during cylindrical gripping.

Area of Science:

• Biomechanics
• Human Factors Engineering
• Musculoskeletal Research

Background:

• Accurate phalangeal kinetics are crucial for investigating musculoskeletal disorders related to gripping.
• Previous methods using pressure film grids on cylindrical handles have limitations in precise force analysis.

Purpose of the Study:

• To develop and validate a novel method for automatically segmenting pressure maps to quantify phalangeal kinetics during cylindrical gripping.
• To fuse hand kinematics with pressure film data for enhanced analysis.

Main Methods:

• Modeled phalanges as conic frusta and projected them onto a pressure grid to create regions of interest (ROIs).
• Fused six degree-of-freedom hand kinematics with kinematic calibration of a cylinder-wrapped pressure film.
• Summed surface-normal force vectors within each ROI to determine reaction force and center of pressure.

Main Results:

• The method successfully segmented pressure maps for subjects with varying hand dimensions gripping different sized cylinders.
• Phalangeal force magnitudes were comparable to previously reported values.
• A surrogate model achieved a classification F-score above 0.95, validating the segmentation accuracy.

Conclusions:

• The presented approach offers an automated and accurate method for segmenting pressure maps.
• This technique is effective for quantifying phalangeal kinetics during cylindrical gripping.
• The findings support the application of this method in studying hand biomechanics and related disorders.