The more axis, the more chance of accumulating errors. Without a closed loop, 5-axis machines would be machining nightmares. I have a closed loop mill and I recently built an open-loop one for little projects. In the open-loop one, I can see where I lose steps. Over time, if that problem isn't addressed, the home(zero) drifts.
As a side note, I plan on adding a CNC rotary table to one of my mills. Closed loop is a must. That will make my design harder. (closed loop on a stepper? Yikes!)
What are the most significant technology advances (software or hardware) that are improving these applications for 5-Axis machining? Obviously there are advances in position accuracy and repeatability of the feedback devices and more available processing power, but are there also algorithm developments and more sophisticated application programming techniques that are driving the advances in this area as well?
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