Experimental Investigation To Study the Influence of Handle Diameter on Low‐Frequency, Hand–Arm Vertical Vibration

Abstract

Handle vibration from equipment or machines influences musculoskeletal activity as well as comfort in handling the same. New technology can be worse than no technology if it was not developed correctly as ergonomic research has clearly demonstrated the relationship between injury risk and poorly designed hand tools. Clinical and epidemiological studies have shown that operators of handheld power tools are prone to develop various vibration‐induced disorders of the hand and arm, which are collectively referred to as “hand–arm vibration syndrome.'' The vibration direction has a great influence on the transmitted vibration. The present study focuses the effects of low‐frequency vertical vibration on hand to shoulder from handles of different size. The electrodynamic exciter is used for simulating vibration to a vertical handles of four different diameters. PULSE LabShop software is used for evaluating the magnitude of vibration in different frequency bands. The vibration characteristic data were acquired in the yh axis at the wrist, elbow, and shoulder for bent arm and extended arm postures with vibration excitation of 4.5 m/s2. Transmissibility characteristics are computed to determine the influence of handle diameter in yh vibration transmitted to the hand–arm system. The magnitude of vibration transmitted within the hand, elbow, and shoulder was observed to be dependent on the handle size; larger handles cause higher vibration transmissibility. The results also show that the human hand–arm system in an extended arm posture amplifies the vibration transmitted than bent arm in a small difference. © 2011 Wiley Periodicals, Inc.

Assessment of ergonomically designed handle shapes for low-frequency vibration responses

“…Therefore, it is obvious that the peak transmissibility occurred at the peak frequency (higher frequency) for all the handles. The findings of the present study are in good agreement with those of Alphin et al 19 for varying diameter handles. Table 3 shows the mean vibration transmissibility of the hand-arm system (wrist, elbow, and shoulder).…”

“…The typical first resonance occurred at 10 Hz and that should be the dominant motion of the hand-arm system. Research work carried out by Alphin et al 19 showed that a similar response (peaks) occurred at the wrist, elbow, and shoulder for different diameter handles. Suspended handle designs for grass trimmers were developed by Ko Ying Ho et al, 4 and the peak accelerations were found to be at 80 Hz without considering the hand and handle responses.…”

Muscular fatigue measurements for push‐down tasks in ground demolitions

“…The vibration of a power tool is transmitted to the body via the worker's hand, elbow, and shoulder. It could lead to extra efforts required for tool control and has been reported to be one of the major contributors to musculoskeletal disorders (Alphin et al, 2013). Whether noise plays a role in the development of muscular fatigue is not clear.…”

Finite element analysis to assess the biomechanical behavior of a finger model gripping handles with different diameters

“…Similarly, the compressive stress was reduced by 24.6%, 25% and 39.6%, while the diameter of the handles varied from 30 mm to 50 mm during 20 N, 40 N and 50 N respectively. Experimental work carried out by Alphin et al [3] with various diameter handles showed that the minimum vibration transmissibility occurred at the wrist, elbow and shoulder for maximum diameter handles. But the trend varies, since an increase in grip force increases the compressive stress in the finger soft skin model.…”