Accurate and repeatable location for robot handling

[Cameronke]

I am currently designing a bio-tech robot that is to have trays loaded and unloaded vertically. It is important that we locate quickly to about 100 micron accuracy (X,Y & Z). We are having a debate regarding the best design for a locating pin/receptacle combination. Three point fixing to achieve a well defined plane seems the way to go. However our first thought is to use a tapered pin with a shoulder going into a slight clearance bore and the same pin into an oval bore and a third pin with a third generous clearance bore. I have been considering using tapered pins into tapered bores / slots but been concerned at variation in altitude due to variations in taper / contamination etc.
I would really value any ideas and comments

Best regards to all

 

[GregLocock]

By oval you mean a straight sided figure with semicircular ends, right?

In that case you have come up with the same solution as we did for a similar but different problem.

Later it was cost reduced to 3 clearance holes - grrrr. Cheers

Greg Locock

 

[modir]

Dear,
Positioning is universal problem in the engineering. Now there are couple things to be considerate before giving any definite solutions.
But in general,
1 Use of encoders, LVDT or triangulations sensors are reocmaded depending on the working environment and the product nature.
Use the goggle to know more about this processes. Other wise contact me back with your need. I will be more than happy to share my information.
Thanks

 

[GregLocock]

Assuming it is a 'normal' size robot, ie roughly man size, then 100 micron (4 thou) is a fairly tight spec for placement. Cheers

Greg Locock