I have now posted the results of FPath Experiment 010. In this experiment a small stepper motor driven XY stage was created out of the medium linear actuators (documented in Experiment 008) and some LEGO bricks.
The controlling software for the FPath project was improved and it can now position a small tool (represented in this experiment by a segment of 100 micron wire) with about 10 micron accuracy. This can be done manually (using the WASD keys) or via automatic target seeking behaviour. Furthermore, this target seeking algorythm has been extended to demonstrate path following.
I just thought that some of you might be interested in how it was done. The video explains all: https://youtu.be/rHwGZN5nuRI
The image below shows the little COTS XY stage. (click on the image to enlarge, watch the video for context)
That moving from point to point method is going to work well with the "dipify" code. Just move up on Z before positioning, dip when it's in place, get back up out of the way, and seek the next point.
ReplyDeleteJust as long as the Z move down is cautious enough not to overshoot :)
I do think it would work well with the "dipify" methodology - by the way, impressive progress with that today!
DeleteI have an idea for handling the overshoot on the Z move which might prove out. Basically it works as follows: As we all know, the focal plane is very thin at these magnifications - so maybe we can turn that annoying problem into a feature. If the probe at touchdown is in focus and I can write some image recognition code to detect the amount of blurring when it is pulled off the work surface, then it should be possible to drop the probe back down and detect when it is once again in focus. The detected blur level would go back to zero. I bet a theoretical Z height resolution of about 2-3 microns could be possible. It all depends on the depth of the focal plane.
I haven't put much thought this yet - it is all just pie-in-the-sky. Probably others have though - my phone camera autofocuses very well at a wide variety of ranges.