Proceedings of SerbiaTrib '13

Serbian TribologySocietySERBIATRIB‘1313th International Conference onTribologyKragujevac,Serbia, 15 – 17 May 2013Faculty of Engineeringin KragujevaccOPTIMAL DESIGN OFA CAMMECHANISMWITHTRANSLATING FLAT-FACE FOLLOWERUSINGG GENETICALGORITHMI. Tsiafis 1 , S. Mitsi 1 , K.D. Bouzakis 1 , A. Papadimitriou 11 AristotleUniversity of Thessaloniki, Departmentt of Mechanical Engineering, Greece,tsiafis@eng.auth.gr, mitsi@eng.auth.gr,bouzakis@@eng.auth.gr, thanpap22@gmail.comAbstract: The optimumm design of f a cam mechanism is a time consuming task, due to the numerousalternativesconsiderations. In the present work, the problem of designn parameterss optimization of a cammechanism with translating flat-facefollower is investigatedfrom a multi-objective point of view. The designparameters,just like the cam basecircle radius, the follower face width and thee follower offset can bedetermined consideringas optimization criteriaa the minimization of the cam size, off the input torque and ofthe contact stress. During the optimization procedure, a number of constraints regarding the pressure angle,the contact stress, etcare taken into account. The optimization approach, based on genetic algorithm, isapplied to find the optimal solutionss with respect to the afore-mentionedd objective function and to t ensure thekinematic requirements. Finally, the dynamic behaviour of the designed cam mechanism is investigatedconsideringthe frictional forces.Keywords: Cam mechanism, geneticalgorithms, , contact stress, optimization.1. INTRODUCTIONThe optimal design of cam mechanismm ishandled in many publications [1-5], where variousconstraints and methods are considered. Αnon-known as SUMT algorithm is used in [3]foroptimum synthesis of a disk cam mechanism withswinging roller follower.In [4] the designparameters are determined by the minimizationn oflinear programming technique with constraints,the maximum compressive stress at the contact areaof a cam-disk mechanism with translating rollerfollower, where the camprofile is described withthe aid of cubic spline functions. Tsiafis ett al.present in [ 5] a multi-objective procedure basedd ongenetic algorithmsto optimize the designparameters of a disk-cam mechanism with a rollerfollower.In the present paperthe problemof the designparameters optimizationof a cam mechanism witha reciprocating flat-face follower is investigated,using multi-objectiveoptimizationwith geneticalgorithm. The design parameters for this typee ofmechanism are the radius of the cam base circle,the follower face width andd the follower offset. Theoptimization iss achieved by the development ofprograms usingg the high level computing languageMATLAB withh the GA (genetic algorithm) toolboxapplication. Furthermore, the dynamical analysis ofthe designed mechanism m consideringfriction isinvestigated.2. MATHEMATICAL FORMULATIONA cam mechanism withh a translating flat-facefollower is shown in figuree 1. The camis assumedto have constant angular velocity. The profile of thecamcan be determined considering thekinematicalanddynamical requirementss of the mechanism.The design parameters under optimization arethe cam base circle c R b , thee width follower face Landthe follower offset e as shown in figure 1.The optimization of the design parameters of thecammechanism can beachieved by theminimisation off the cam size, of the torque requiredto drive the camm and the contact stress between thecamand the follower.27013 th International Conference C onn Tribology – Serbiatrib’13