DasGupta and Ghosh used a constant pressure angle to assess jamming of the follower in its guide based on the follower–guide friction. studied the effect of the error in cam profile on the behavior of nonlinear dynamics of the oscillated roller follower by solving the nonlinear second order differential equations. They showed that the cam and the follower kept permanent contact at low speeds, while the separation and oblique impact will happen at high speeds. extended a transient impact hypothesis of the contact model by considering the tangential slip between the cam and the follower. They determined the kinematic parameters of the dynamic force analysis at different motion for the follower such as constant velocity motion, cycloidal motion, parabolic motion and simple harmonic motion. Desai and Patel determined the critical angular speed when the follower jumps off the cam. The detachment between the cam and the follower has been detected based on bifurcation diagram and chaos. They concluded that the detachment and the separation between the cam and the follower occurs when there will be a difference in angular velocity between the cam and the follower at the contact point. observed experimentally the detachment when the contact force exceeds the restoring force at critical velocity region. measured the contact force experimentally during the rotation of a circular eccentric cam and an engine spline cam at different rotational speeds and preloads in the presence of lubricant film thickness between the cam and the follower. They showed different conditions for the contact at low and high magnification to detect the angular positions of the cam. designed an apparatus to measure the contact force using an optical interferometry sensor with high speed camera. They improve numerically the level of film thickness lubricant by taking into consideration the parabolic shape of the pressure distribution through cam depth which reduced the detachment between the cam and the follower. discussed the parameters that affect the contact problem between the cam and flat-faced follower such as radius of curvature, surface velocities and applied load under thin film of lubricants.
They proposed a mathematical model for the cam profile with a variable speed to change the follower motion by using Bezier function. Yan and Tsay solved the separation phenomenon problem between the cam and the follower by increasing the preload rate of the spring force. used the Hertzian contact theory to calculate the contact stiffness by analyzing the coefficient of restitution model using single degree of freedom when the cam was spinning about a fixed point.
The peak of nonlinear response of the follower displacement was reduced to (15%, 32%, 45%, and 62%) after using multiple degrees of freedom systems. The friction and impact were considered between the cam and the follower and between the follower and its guide. SolidWorks program was used in the numerical solution while high speed camera at the foreground of the OPTOTRAK 30/20 equipment was used to catch the follower position. Nonlinear response of the follower displacement was calculated at different cam speeds, different coefficient of restitution, different contact conditions, and different internal distance of the follower guide from inside. Multi-degrees of freedom (spring-damper-mass) systems at the very end of the follower were used to improve the dynamic performance and to reduce the detachment between the cam and the follower. The follower displacement and the contact force between the cam and the follower were used in the detection of the detachment heights.
The detachment between the cam and the follower were detected using largest Lyapunov exponent parameter, power density function of Fast Fourier Transform (FFT), and Poincare’ maps due to the nonlinear dynamics phenomenon of the follower. The detachment between the cam and the follower was investigated for different cam speeds (N) and different internal distance of the follower guide from inside (I.D.).
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