The present study has established equal sensation curves for steering wheel hand-arm rotational vibration. Psychophysical response tests of 20 participants were performed in a steering wheel rotational vibration simulator using the category-ratio Borg CR10 scale procedure for direct estimation of perceived vibration intensity. The test stimuli used were sinusoidal vibrations at 22 third octave ...

The foresters workers are especially exposed to hand-arm transmitted vibrations. These vibrations can cause the complex of vascular, neurological and musculoskeletal disorders, collectively named hand-arm vibration syndrome. Among these, the most common disorder is the vibration-induced white finger. The group exposed to vibration included: 4 hand saws cutters, 5 electric saws cutters, 3 tracto...

This invited paper reviews experimental studies of the frequency-dependence of absolute thresholds for the perception of vibration, equivalent comfort contours, temporary changes in sensation caused by vibration, and reductions in finger blood flow caused by hand-transmitted vibration. Absolute thresholds depend on the contact conditions but for a typical hand grip the thresholds show greatest ...

This study was conducted to clarify the effects of vibration on the peripheral nerves. Rat tails were exposed to vibration (acceleration 56.9 m/s2, frequency 60 Hz, amplitude 0.4 mm for two or four hours daily, six days a week. The maximum motor conduction velocity (MCV), the amplitude of evoked response, and the motor distal latency were measured on rat tail nerves every two months. Thin secti...

This study is investigated the optimum parameters for a tuned mass damper (TMD) under the seismic excitation. Shuffled complex evolution (SCE) is a meta-heuristic optimization method which is used to find the optimum damping and tuning frequency ratio for a TMD. The efficiency of the TMD is evaluated by decreasing the structural displacement dynamic magnification factor (DDMF) and acceleration ...

This paper deals with the experimental and numerical assessment of the vibration suppression of smart structures using piezoelectric shear actuators. Experimental results are presented for an adaptive sandwich cantilever beam that consists of aluminum facings and a core made of two piezoelectric shear actuators and foam. The electric Þeld is applied perpendicular to the poling direction of the ...

UNLABELLED Previous studies on vibration training have all been based on protocols at different combinations of frequencies and amplitudes without controlling the loading intensity. OBJECTIVES This study investigated the effect of an 8-week vibration training program, under identical acceleration loads with various frequencies and amplitudes, on jumping performance, muscle activation and body...

The objective of this study was to compare the lateral apparent mass of the seated human body measured in response to lateral and roll motions. The lateral apparent mass was measured at the seat surface using a rigid flat seat with no backrest. The axis of rotation of the roll motions was also at the seat surface. Tests were conducted using pseudo-random motions band-limited at 0.2 and 2 Hz rep...

This paper analyzes the comfort of wheelchair users when a sliding-mode trajectory-tracking controller is used. The transmission of the horizontal (fore-and-aft) vibration to the head-neck complex (HNC) in the seated human body may cause unacceptable discomfort and motion sickness. A double-inverted pendulum model with two degrees of freedom is considered as a model for the HNC. The user comfor...