Re: I'm curious

The should be titled : I'm Ignorant

Really, I don't know nearly as much as most of you. The amount of experience here is amazing.

I do know that my home built mill / router is running on steppers, diven by Gecko's, and told what to do by Mach3. I NEVER lose steps unless I try to do somthing beyong the capabiliities of the machine. When used withing it's capabilities it is flawless. No it does not move at 400ipm (100 is it's normal rate) and it will not handle deep cuts in much of anything, but it does whit I designed it to do perfectly.

I have a question about the error corection of the closed loop system. In the closed loop system I understand that when the expected position and the actual postion do not aggree, the system will attempt to correct or catch up.

Now, I'm making a 3D cut (X, Y, and Z all moving) and my Y axis begins to lose position won't the loss of this position and any correction applied ruin the work?

Seems to me that a systems design should NOT expect to have to deal with lost position. Isn't the the real point. Build the machine for it's intended purpose.

Hey, I could be wrong. :)

BTW I have a telescope driven by servos. Backlash, I have plenty. The software knows about the backlash and compensates when a direction change is made. During normal viewing or tracking of an object, a direction change is never made. Therefore no backlash to worry about. If I know I have 30 ArcSec of backlash, program it in. My scope is nothing like the one you guys are talking about (quite impressive) but my simple system works for me. (I'll be out looking for Neptune tonight) Happy Gazing

Ted


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