Disc Cam Component Generator with Changing RPM

[c13intzUPK2K]

I am trying to figure out if I can generate a cam with changing speeds. For example, I want a cam that rotates 180° in .061s and then continues to rotate another 180° in .659s. The first 180° is my intended cam path and the second 180° is a dwell (see attached picture). I understand the physical shape of the cam would be the same as a cam that rotates 360° in .122s, but I want to see how the outputted results may change. This is relevant as it is important while sizing an appropriate servo motor for my application as the speeds will be changing which changes my servo requirements. I also understand I could rotate only 180° in .061s, dwell without movement for .659s, and then repeat using the same profile on both halves of the cam. However, the constraints given to me are to perform a full 360° rotation eliminating the need to start and stop the servo motor, it can just constantly rotate at varying speeds. Is there a way to simulate this using the disc cam component generator?

 

[jan.vonasek]

Hi @c13intzUPK2K,

Cam generators do not support changing speed.

If you want to play with changing speed the workaround may be combination of the steps below

• Calculate for multiple speeds and export data using Save button above the graph. Note: number of exported data depends on Number of Split Points.
• Combine data from exports or use single export and modify data using speed ratio function.
• Include forces related to speed acceleration.

Note: Because your changing speed part is without lift the only forces should be related to speed acceleration which is not counted by generator. You may insert cam and try Dynamic Simulation or calculate yourself using cam body properties.