Device to measure distance

[cnick]

I’m working on a design for a simple mechanical device that will disperse objects at a precise fixed distance entered on a control panel (i.e. every 2 ft.) The machine will roll on the ground. Would connecting a plc to a rotary encoder device be a cost effective way of measuring distance? After zeroing, I want the machine to perform an operation at a programmed distance (output a signal once the machine reaches a programmed distance). The operation would be repeated at the fixed distance until an overall distance is reached (accumulated).

 

[jbartos]

Suggestion: The PLC could be cost effective unless you:
1. Have a computer on the machine already; or
2. Intend to design a PLC equivalent; or
3. Invent some simpler way based on you ingenuity.