Nonlinear Dynamics Simulation of Stress Concentration Factor of Pear Cam and Roller Follower Mechanism With Clearance

Abstract

The effect of stress concentration factor on the nonlinear dynamics phenomenon of the follower is studied at different internal distance of the follower guides from inside (I.D.) and different cam speeds (N). The stress concentration factor is examined at the contact point and around the square grooving key. The contact between the cam and the follower and between the follower and its guides are considered using SolidWork program. Three different involutes’ profiles of the pear cam are used to select the optimum cam profile. Phase-plane diagram is used to detect the periodic and non-periodic motions over times. Moreover, the dynamic tool of Wolf algorithm code is used to calculate the local Lyapunov exponent against number of samples. The overshoot of the transient response of local Lyapunov exponent parameter is done at different cam speeds and different follower guides’ clearances. Photo-elastic device is used to check the value of stress concentration factor experimentally. Multi spring-damper-mass model is used on the follower stem to reduce the contact stress at the contact point and around the square grooving key.