Experience Effect in Power Tool Operations: A Mechanical Model Perspective

動力工具操作之經驗效應：一個力學模式之觀點

林嘉華(Jia-Hua Lin) ； Raymond W. McGorry ； 張堅琦(Chien-Chi Chang)

《人因工程學刊》 15卷2期 (2013/09) Pp. 53-60

https://doi.org/10.6273/JES.2013.15(2).01

摘要

Previous study demonstrated that a single-degree-of-freedom mechanical model can represent a human power tool operator subjected to impulsive torque reactions. Using only novice tool users, it was shown by mechanical modeling that the response to tool torque reaction depended on workstation location and orientation, and varied among users (Lin, Radwin, & Richard, 2000). The current study hypothesized that the mechanical model elements among experienced tool operators may be different from novice users. A laboratory protocol was carried out to measure the mechanical parameters among the novice and experienced tools users. The results demonstrate the difference between the two groups. Experienced operators had less stiffness, but greater mass moment of inertia than novice operators did. Overall operator hand-arm stiffness was significantly affected by handle height (p＜ 0.001) and distance (p = 0.001). Difference in mechanical properties may represent the strategy developed by the experienced users to minimize the impacts from impulsive torque reactions.

關鍵字

生物力學 ； 職業安全 ； 手與工具介面 ； 經驗 ； 力學模式

並列摘要

Previous study demonstrated that a single-degree-of-freedom mechanical model can represent a human power tool operator subjected to impulsive torque reactions. Using only novice tool users, it was shown by mechanical modeling that the response to tool torque reaction depended on workstation location and orientation, and varied among users (Lin, Radwin, & Richard, 2000). The current study hypothesized that the mechanical model elements among experienced tool operators may be different from novice users. A laboratory protocol was carried out to measure the mechanical parameters among the novice and experienced tools users. The results demonstrate the difference between the two groups. Experienced operators had less stiffness, but greater mass moment of inertia than novice operators did. Overall operator hand-arm stiffness was significantly affected by handle height (p＜ 0.001) and distance (p = 0.001). Difference in mechanical properties may represent the strategy developed by the experienced users to minimize the impacts from impulsive torque reactions.

並列關鍵字

Biomechanics ； Occupational safety ； Hand-tool interface ； Experience ； Mechanical model

參考文獻

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Joyce, G. C., Rack, P. M. H., & Ross, H. F. (1974). The forces generated at the human elbow joint in response to imposed sinusoidal movements of the forearm. Journal of Physiology, 240, 351-374.

Kihlberg, S., Kjellberg, A., & Lindbeck, L. (1993). Pneumatic tool torque reaction: reaction forces, displacement, muscle activity and discomfort in the hand-arm system. Applied Ergonomics, 24, 165-173.