Investigation of hand forces applied to a pruning tool - pilot study

Area of Science:

• Agricultural Engineering
• Ergonomics
• Plant Science

Background:

• Winter pruning is essential for plant cultivation, but repetitive hand scissor use poses musculoskeletal disorder (MSD) risks.
• The manual nature of pruning involves frequent, high-frequency gestures, increasing hand-wrist strain for agricultural workers.

Purpose of the Study:

• To quantify the forces exerted by operators during pruning tasks.
• To identify factors influencing applied forces and hand regions most affected.

Main Methods:

• Sensored scissors and a sensor matrix measured peak and average forces during branch cutting across 3 diameters.
• Eight participants cut branches from 5 wine-grape cultivars, with forces recorded in 6 hand areas.

Main Results:

• Branch diameter and humidity significantly impacted cutting forces (peak and average).
• Cut duration correlated inversely with hand size; the middle finger area experienced the highest forces.
• The hand region furthest from the thumb showed the least force exertion.

Conclusions:

• Identified key factors (branch diameter, humidity) influencing pruning forces and high-strain hand areas.
• Findings provide insights for developing strategies to prevent MSDs in pruning operations.
• Recommendations for further research include larger subject pools for broader applicability.