Designing a Stepper Motor System

Lautarocondor

Hello,

I am trying to design a system that incorporates a stepper motor that drives a “guillotine” like cutter driven by a stepper motor, a simple up and down selector(arrow buttons) to decide cutter depth, and a seven segment display showing the selected position (value between 0-99).

When I select a value, lets say (0), I want the stepper motor to lower the cutter to the fully closed position after the trigger switch is pressed. And then return to the fully open position. And when the value (50) is selected it will close about halfway and then open.

Thanks for your help

Post Edited By Moderator (Chris Savage (Parallax)) : 9/6/2006 5:00:29 AM GMT

Franklin

Figure out how many revolutions it takes to fully close then send that many revolutions to the stepper and then again in reverse. Take a look at the publications on controlling stepper motors on the parallax site.

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- Stephen

metron9

I use stepper motors in gauges, they have very low torque. To zero the gauge I turn the motor on one direction for more steps than it takes to turn the full span, it bumps against the side it is turning into. When the loop is finished I know the position of the gauge pointer.

If you are cutting something with this device and you have high torque this wont work. Typically a stop sensor (Micro switch) is used to tell the processor when the position is at a known position. Fully open and fully closed sensors could be used, the stamp would count the number of steps from one to the other then divide by 2 to place the blade at center. Scale the number to fit your 0 to 99 close to open after your program measures the full step range.

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Think outside the BOX!