International Journal of Innovative Technology and Exploring Engineering (IJITEE) ISSN: 2278-3075, Volume-9 Issue-1, November, 2019 4653 Published By: Blue Eyes Intelligence Engineering & Sciences Publication Retrieval Number: A4941119119/2019©BEIESP DOI: 10.35940/ijitee.A4941.119119 Abstract: Modeling of optimized flexible four bar mechanism considering joint clearances are developed at first. The dynamic analysis such as Moment, Torque, Energy and structural analysis such as Deformation, different mode of Stress are done by considering load in coupler point of optimized flexible four bar linkage. The deformation and stress are compared by considering different materials. Lagrange's equation is used to define the direction of the joint clearance. Differential evolution algorithm is used to optimize the length of links which reduce the gap between the desirable and actual path. Keywords: Optimized linkage; dynamic and structural analysis; Lagrange’s equation; differential evolution I. INTRODUCTION A system having no clearance is assumed as rigid link and having clearance is the flexible linkage. An external force is applied on the linkage. Due to the given external force, clearance affects the mechanisms. In a dynamically balanced body, the elastic deformation with high input speed affects the mechanism. Erkaya and I. Uzmay [1] represented that how the joint clearance affect the path and transmission angle and the link parameters were optimized by the help of GA technique in the 4-bar linkage. S.D.Yu and W. L. Cleghorn [2] represented the dynamic behavior of 4-bar linkage according to the critical running speed and conditions by which the system gets balanced is obtained experimentally and validate with the analytical value. H.Sen Yan and R.C. Soong[8] designed and verified mechanism with its desired position, expected motion and dynamically balanced with considering two conditions i.e. link with different positions and mass distributed in each link. In this paper, the dynamic and structural analysis is done are compared with considering different materials. Stress analysis of the model is done with the help of ANSYS workbench. The 4-bar linkage with joint clearances is analyzed dynamically with the help of ADAMS by considering the same as for the stress analysis. The results of dynamic and structural analysis of the flexible 4-bar linkage are compared with mechanism before optimization and mechanism after optimization. II. MODELLING OF THE FOUR BAR MECHANISM: (a) Design of Joint clearances: Revised Manuscript Received on November 10, 2019. * Correspondence Author Ruby Mishra*,SME,KIIT deemed to be university, Bhubaneswar, India. E-mail:rubymishrafme@kiit.ac.in Rojalin Behera,Tube investment of India limited, Chennai,India. E-mail:rojalin44.behera@gmail.com, Joint clearance in the flexible 4-bar mechanism is defined as the space between the pin center to the hole centre. Joint clearance acts same as the journal bearing in which pin act as a journal and hole act as a bearing. In an operating condition, pin gives the impact force on the surface of the hole. The impact force between pin and hole surface is tangential in nature. Fig.2.Schmatic diagram of a 4-bar flexible linkage considering joint clearances Fig.3.Vector representation of four bar flexible mechanism (b) Design model of four bar mechanism before optimization: Cconsidering the link lengths considering joint clearances at crank-coupler and coupler-follower the flexible 4-bar linkage model is developed [1]. The mechanism was solved by using the Equation of Lagrange and Differential Evolution algorithm (DE). By using the vector loop equation [11], 3 c  and c 4  are obtained which is given below: 0 3 2 4 3 2 1 3 2 4 3 2 1             i i i i i i e r e r e L e L e L e L (1) c 3  and c 4  are obtained by using the below equation: Design Improvement of Four Bar Linkages Using Different Soft-Computing Methods Ruby Mishra, Rojalin Behera