Point of optimal kinematic error: Improvement of the instantaneous helical pivot method for locating centers of rotation

JOURNAL OF BIOMECHANICS

卷:47

Article

De Rosario, Helios^1,3  Page, Alvaro^2,3  Mata, Vicente⁴ 

[1] Univ Politecn Valencia, Inst Biomecan Valencia, E-46022 Valencia, Spain

[2] Univ Politecn Valencia, Dept Fis Aplicada, E-46022 Valencia, Spain

[3] CIBER Bioingn Biomat Nanomed CIBER BBN, Grp Tecnol Sanitaria IBV, Valencia, Spain

[4] Univ Politecn Valencia, Dept Ingn Mecan & Mat, E-46022 Valencia, Spain

关键词: Center of rotation;    Instantaneous helical axis;    Functional calibration;    Optimization;   

DOI  :  10.1016/j.jbiomech.2014.02.003

来源: Elsevier

【 摘 要 】

This paper proposes a variation of the instantaneous helical pivot technique for locating centers of rotation. The point of optimal kinematic error (POKE), which minimizes the velocity at the center of rotation, may be obtained by just adding a weighting factor equal to the square of angular velocity in Woltring's equation of the pivot of instantaneous helical axes (PIHA). Calculations are simplified with respect to the original method, since it is not necessary to make explicit calculations of the helical axis, and the effect of accidental errors is reduced. The improved performance of this method was validated by simulations based on a functional calibration task for the gleno-humeral joint center. Noisy data caused a systematic dislocation of the calculated center of rotation towards the center of the arm marker cluster. This error in PIHA could even exceed the effect of soft tissue artifacts associated to small and medium deformations, but it was successfully reduced by the POKE estimation. (C) 2014 Elsevier Ltd. All rights reserved.

【 授权许可】

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