Measurement of hand-vibration transmissibility by non-contact measurement techniques

Abstract

Background: Workers who use hand-held vibrating tools may experience finger blanching attacks due to episodic vasospasm in the digital vessels. In occupational medicine, the pathological consequences to the exposure to handtransmitted vibration are known as vibration induced white finger (VWF). In many cases, workers are recommended to use anti-vibration gloves and a standard procedure (ISO 10819) is used to test and qualify such anti-vibration gloves. Some problems and limits are known for what concerns the measurement and procedure proposed by this standard. Materials and methods: Hand-arm vibration transmissibility (ratio between rms acceleration on different points of the upper side of the hand and the handle rms acceleration) of 13 healthy subjects (main BMI: 24.3 [kg/m 2 ]) was measured using a mono-axial accelerometer on the handle and a laser Doppler vibrometer on several points on the hand. The laser vibrometer eliminates any mass loading effect on the hand tissue. Seven single frequency excitations (rms acceleration amplitude: 3 m/s 2 ) have been tested: 15, 20, 30, 50, 70, 90 and 110 Hz. Closed loop control of the handle acceleration is provided. Monitoring of the push force (50 ± 5.0 N) has been carried out during the test. Results: Transmissibility higher then one (1.54) has been measured at the tip of the fingers, especially for vibration frequencies lower then 70 Hz, while transmissibility lower then 1 (0.20) is reported on the hand knuckles for frequencies higher then 30 Hz. Conclusions: The measurement procedure presented a non-contact measurement of the vibration transmissibility of the human hand and in particular its spatial distribution over the hand.

An examination of the vibration transmissibility of the hand-arm system in three orthogonal directions

“…While a 1-D laser vibrometer has been used for the measurement of the transmitted vibration in the direction approximately vertical to the surface of the hand-arm system (Sörensson and Lundström, 1992; Rossi and Tomasini, 1995; Deboli et al, 1999; Nataletti et al, 2005; Scalise et al, 2007; Concettoni and Griffin, 2009; Xu et al, 2011), the feasibility of applying a 3-D laser vibrometer to reliably measure multi-axial vibrations of the hand-arm system has not been proven. Except for a preliminary introduction of the current study (Welcome et al, 2011), the application of a 3-D laser vibrometer for the measurement of 3-D vibrations on the entire hand-arm system was not found during the literature review for this study.…”

The effects of vibration-reducing gloves on finger vibration

“…These problems can be avoided by using a laser vibrometer in the measurement. While the use of a single-direction laser vibrometer for the measurement of hand vibration transmission has been reported by several researchers (Sörensson and Lundström, 1992; Rossi and Tomasini, 1995; Nataletti et al, 2005; Scalise et al, 2007; Concettoni and Griffin, 2009; Xu et al, 2011), a 3-D vibrometer has also been recently used to measure the vibration transmitted to the hand-arm system (Welcome et al, 2011). This technique has made it possible to conduct reliable 3-D measurement of the finger vibration for examining the effectiveness of the gloves for finger vibration exposure protection.…”

Cardiorespiratory interactions: Noncontact assessment using laser Doppler vibrometry

“…These findings add to the growing body of evidence regarding the range of physiological signals, all of interest to psychophysiology, that can be recorded using the LDV method (and kindred methods based on self‐mixing interferometry and laser speckle tracking). In keeping with the general observation that physiology (particularly at the system level) typically includes an appreciable mechanical component, these applications have demonstrated effectiveness in a number of systems including respiration (Marchionni, Scalise, Ercoli, & Tomasini, ; Scalise, Ercoli, & Marchionni, ; Scalise, Ercoli, Marchionni, & Tomasini, ; Scalise, Marchionni, & Ercoli, ), speech (Avargel & Cohen, ), mechanical myogram (Rohrbaugh, Sirevaag, & Richter, ; Scalise, Casaccia, Marchionni, Ercoli, & Tomasini, ), and biomechanics (P. Castellini & Tomasini, ; Nataletti, Paone, & Scalise, ; Revel, Scalise, & Scalise, ; Scalise, Rossetti, & Paone, ; Valentino et al, ), in addition to the CV system. CV variables include the phonocardiogram (De Melis, Morbiducci, & Scalise, ), PTT (De Melis et al, ), heart rate (Marchionni et al, ; Morbiducci, Scalise, De Melis, & Grigioni, ; Scalise & Morbiducci, ), movements of the precordium (Hong & Fox, ; Scalise, Morbiducci, & De Melis, ; Schuurman, Rixen, Swenne, & Hinnen, ), and the BP pulse (Campo, Segers, & Dirckx, ; Capelli, Bollati, & Giuliani, ; Desjardins, Antontelli, & Soares, ; Hong & Fox, ; Y. Li, Segers, Dirckx, & Baets, ; Pinotti, Paone, Santos, & Tomasini, ).…”

“…systems including respiration Scalise, Ercoli, Marchionni, & Tomasini, 2011;, speech (Avargel & Cohen, 2011), mechanical myogram (Rohrbaugh, Sirevaag, & Richter, 2013;Scalise, Casaccia, Marchionni, Ercoli, & Tomasini, 2013), and biomechanics (P. Castellini & Tomasini, 1998;Nataletti, Paone, & Scalise, 2005;Revel, Scalise, & Scalise, 2003;Scalise, Rossetti, & Paone, 2007;Valentino et al, 2004), in addition to the CV system. CV variables include the phonocardiogram (De Melis, , PTT (De Melis et al, 2008), heart rate Morbiducci, Scalise, De Melis, & Grigioni, 2007;, movements of the precordium (Hong & Fox, 1997;Scalise, Morbiducci, & De Melis, 2006;Schuurman, Rixen, Swenne, & Hinnen, 2013), and the BP pulse (Campo, Segers, & Dirckx, 2011;Capelli, Bollati, & Giuliani, 2011;Desjardins, Antontelli, & Soares, 2007;Hong & Fox, 1994, 1997Y.…”