Mechanical Engineering - Theory of machines - Discussion

Low and moderate speed Follows SHM.

@All.

I will explain where all these motions are used:

1) SHM:- In these motion, there is an infinite jerk, vibration and noise so it would be suited for low and moderate speed.

2) Constant acceleration and deceleration (parabolic) :-There are abrupt changes in the acceleration at beginning, midway and the end of the follower motion. At midway, an infinite jerk is produced. So best suited up to moderate speed.

3) Constant velocity:-Due to the infinite inertia forces, it is not suited from the practical point of view.

4) Cycloidal:- There are no abrupt changes in the velocity and the acceleration at any stage of the motion, so it is an ideal programme for high-speed follower motion.

The graph represents of SHM that of uniformity rather than other types of profile.

From the diagram of acceleration and angular displacement of cam, acceleration becomes zero when there is maximum velocity which smoothens motion in the high-velocity rise.

Because cycloidal motion has uniform rise and return.

Thank you all for the explanation.

Thanks to all for the explanation.

The cycloidal cam profile is best suited for high-speed applications because the successive derivatives of the function, ie. velocity, acceleration, and jerk are continuous functions rather than step functions, throughout the motion. Due to this continuity the bearings of the cam and follower are least prone to cyclic stresses, This improves the service life and no noise is present.

Why is cycloidal follower best suited in high-speed applications?

Constant velocity is not practically applicable. SHM and constant acceleration can be used for low or moderate speeds; but there will be jerks.