Estimation of the biodynamic responses distributed at fingers and palm based on the total response of the hand-arm system

The major objective of this study is to develop a modeling method for estimating the biodynamic responses distributed at the fingers and the palm of the hand based on the total driving-point mechanical impedance of the entire hand arm system. A five degrees-of-freedom (DOF) model with a set of constraints proposed in this study was used in the estimation. Three sets of mechanical impedance data measured at the fingers and palm of the hand Were used to examine the validity of the proposed method. The estimated response distributed at the palm was consistent with the measured data even when the real part of the impedance alone was used in the modeling (coefficient of correlation, r(2) >= 0.902). Better agreements between the estimated and measured responses were obtained (r(2) >= 0.929) when the magnitude and phase of the total impedance or the magnitude alone were used in the modeling estimation. In each case, the estimated response distributed at the fingers was also reliably correlated with the experimental data (r(2) >= 0.726) but it was not as consistent with the experimental data as that distributed at the palm. The applications of the proposed method were also demonstrated using five other sets of reported experimental data. This study also demonstrated that the modeling method may also be used to assess the quality of the experimental data in some cases. As a special application of the acceptable data identified in this study, this study also defined a 2-DOF model for the construction of a hand arm simulator for tool tests. The results of this study and the proposed modeling method are expected to contribute to the revision of ISO 10068 (1998). Relevance to industry: Prolonged exposure to intensive tool vibration could cause hand arm vibration syndrome (HAVS). An effective approach to reduce the HAVS is to reduce the intensity of the vibration exposure. The proposed modeling method and the results of this study can be used to help develop better tools and anti-vibration devices for reducing the exposure. The modeling study can also be used to help develop the location-specific frequency weightings for assessing the risk of the location-specific disorders induced from the hand-transmitted vibration exposure. Published by Elsevier B.V.