Gurram R, Rakheja S, Gouw G J
Department of Mechanical Engineering, Concordia University, Montréal, Québec, Canada.
Ergonomics. 1995 Apr;38(4):684-99. doi: 10.1080/00140139508925140.
A matrix of miniature and flexible pressure sensors is proposed to measure the grip pressure distribution (GPD) at the hand-handle interface of a vibrating handle. The GPD was acquired under static and dynamic loads for various levels of grip forces and magnitudes of vibration at different discrete frequencies in the 20-1000 Hz range. The EMG of finger flexor muscles was acquired using the silver-silver chloride surface electrodes under different static and dynamic loads. The measured data was analysed to study the influence of grip force, and magnitude and frequency characteristics of handle vibration on: (i) the local concentration of forces at the hand-handle interface; and (ii) the electrical activity of the finger flexor muscles. The results of the study revealed high interface pressure near the tips of index and middle fingers, and base of the thumb under static grip conditions. This concentration of high pressure shifted towards the middle of the fingers under dynamic loads, irrespective of the grip force, excitation frequency, and acceleration levels. The electrical activity of the finger flexor muscles increased considerably with the grip force under static as well as dynamic loads. The electrical activity under dynamic loads was observed to be 1.5-6.0 times higher than that under the static loads.
提出了一种微型柔性压力传感器矩阵，用于测量振动手柄的手 - 手柄界面处的握力压力分布（GPD）。在20 - 1000 Hz范围内不同离散频率下，针对各种握力水平和振动幅度，在静态和动态载荷下获取GPD。使用银 - 氯化银表面电极在不同静态和动态载荷下获取手指屈肌的肌电图（EMG）。对测量数据进行分析，以研究握力、手柄振动的幅度和频率特性对以下方面的影响：（i）手 - 手柄界面处力的局部集中情况；（ii）手指屈肌的电活动。研究结果表明，在静态握持条件下，食指和中指指尖以及拇指基部附近存在较高的界面压力。无论握力、激励频率和加速度水平如何，在动态载荷下，这种高压集中向手指中部移动。在静态和动态载荷下，手指屈肌的电活动均随着握力的增加而显著增加。观察到动态载荷下的电活动比静态载荷下高1.5 - 6.0倍。
