Stepper motor

Eagle1

I recently obtained a stepper motor from Parallax. Nice little unit which works as advertised. My question is: Can th stepper be programmed to stop in a certain position on loss of power without going thru extraordinary effort ? It seems to me that I am missing some fairly obvious method.
Thank-You-In-Advance

Post Edited (Eagle1) : 7/17/2010 11:34:22 AM GMT

Franklin

I don't think you could get it to stop in a specific position on power fail bacause of no power but if you were to keep track of where it was or used an absolute encoder you could have it return to a home position on power restore. Or you could have backup power to allow it to run after power fail until it reset to home position then shut down.

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- Stephen

erco

Without power, steppers become shleppers: loosey-goosey with no holding torque. There's no guarantee a stepper will stay in position, so it's "a bit dodgey" to assume it's right where you left it. My Hero 2000's arm is all stepper motor-based. It goes through a painfully slow homing routine each time you initialize it, which runs each joint to its extreme and closes a limit switch to verify the home position.

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·"If you build it, they will come."

Eagle1

Thanks erco and Franklin , both posts give me direction