Introduction to the 'Cam Mechanical System'.


Together, the Cam Mechanical System has a:

'Simple' Input Motion

Usually, the cam has a 'simple' motion. It is said to be the input motion.

'Complex' Output Motion

Usually, the follower* has a more 'complex' motion.  It is said to be the output-motion.

Input Transmission

The mechanical components from the motor [power source] to the cam are said to be the input-transmission.

Output Transmission

The mechanical components from the follower to the payload** are said to be the output-transmission.

* Follower : also called the Cam-Follower

** Payload : Other names for the 'payload' are 'load', 'tooling', and 'end-effector'.

You cannot design a cam in isolation of other components in the mechanical system. The design and selection of the mechanical components influence the cam-system's performance. This applies particularly to the input and output-transmissions, which usually consist of a variety of conventional machine elements [such as shafts, gears, couplings, sliders, and linkages], that are connected together in series. The inertia, rigidity and backlash of the transmission component are of particular importance.

Equally important is the motion you design for the payload. A poor motion will needlessly incite vibrations in any mechanical system. A good motion will give you a machine that lasts longer, jams less frequently, and has the same capital cost as a machine with poor motion-design.

Motion-Design for a single axis is fairly straightforward. Motion-Design for multi-axis machines, with many interacting mechanisms and complex material-to-machine interactions, requires experience, skill and a good understanding of the motion-design requirements as a whole.

Cam Mechanism : from the 'Power-Source' to the 'Payload'



Power Source, or Drive

This is Power Source for the cam system. It is frequently an electric motor, a servomotor.

See Torque, Overrun and Power

Input Transmission

The mechanical components between the 'Power-Source' and the Cam.

For example: shafts, couplings, gearbox, levers, ...

See Transmission Design Considerations

Cam + Cam-Profile

'Cam' is the Part.

'Cam-Profile': the shape that is in continuous contact with the Cam-Follower

See Cam Types


Efficient transfer of motion and power from Cam-Profile to the Cam-Follower.

The action must be efficient and have a long life. You must consider: materials, metallurgy, lubrication, heat treatment, wear, rolling contact fatigue, backlash, ...

See Efficient 'Action' from Cam to Follower

Follower + Cam-Follower

'Follower': the Part.

'Cam-Follower': the shape that is in continuous contact with the Cam-Profile

See Cam-Follower Types


Output Transmission

The mechanical elements between the follower and the tool.

For example: ball-screws, conveyors, rack/pinions, slides, belts/pulleys/chains/sprockets, ...

See Transmission Design Considerations

See Dynamic Response: Period-Ratio, Damping and Backlash

See Torque, Overrun, Power


The Payload is the element to which the conventional 'tooling' is rigidly attached.

The 'tooling' is anything that comes into contact with or does work on the work-piece, product or package. Examples are: a punch, a rotary table, a linear conveyor, a pusher, a workpiece carrier....

'Payload', 'Tooling' and 'End-Effector' are different words for the same machine elements.

See Payload Types

Tutorial and Reference Help Files for MechDesigner and MotionDesigner 13.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd