A method of identification of kinematic chains and distinct mechanisms

Ashok Dargar; Ali Hasan; Rasheed Ahmed Khan

Ashok Dargar Department of Mechanical Engineering, Maharaja Agarsain I nstitute of Technology, Pilkhuwa
Ali Hasan Department of Mechanical Engineering, Faculty of Engineering and Technology Jamia Millia Islamia University, NewDelhi
Rasheed Ahmed Khan Department of Mechanical Engineering, Faculty of Engineering and Technology Jamia Millia Islamia University, NewDelhi

Abstract

A new method is proposed to identify the distinct mechanisms derived from a given kinematic chain in this paper. The kinematic chains and their derived mechanisms are presented in the form of a flow matrix. Two structural invariants, sum of the absolute values of the characteristic polynomial coefficients (SCPC) and maximum absolute value of the characteristic polynomial coefficient (MCPC) are determined using the software MATLAB. These invariants are used as the composite identification number of a kinematic chain and mechanisms and clearly identify the distinct mechanisms derived from the family of 1-F, 8-links and 10-links KC as well as 2-F, 9-links simple joined KC. This study will help the designer to select the best possible mechanism to perform the specified task at the conceptual stage of design. The proposed method does not require any test for isomorphism separately. Some examples are provided to demonstrate the effectiveness of this method.

Keywords

kinematic chain (KC), distinct mechanism (DM), flow matrix, SCPC, MCPC,

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