Slide for extreme temperatures

[IES]

We are working in an automotive test equipment. First phase is complete, now we are at the second phase.
In 2nd stage we have to build a xyz table with servomotors or steper motors. The travel distance for the movement is 12inches in each axis, the accuracy is .05in. My problem: The XYZ has to be inside of a temperature chamber where tests will be perform, however temperature range is from
-40ºC to 85ºC. If the slides are aluminum and stainless steel material should I have problems with accuracy?

 

[Barry1961]

Good problem. With the temp. swing you are talking about you max expansion should be around .05" but just in the guide length. As long as this does not cause the guides to warp you should be ok.

You will also have to worry about your drive screw or belt since it's expansion will cause a more immediate effect.

I would have one guide rail fixed and let the other float. Also if you have a steel rail on a aluminum base you would need some compliance between them lenght ways. Maybe just tighten a couple of screws in middle and have screws on ends snug.

.050" sounds like plenty of slop till you start adding things up.

Good Luck, Barry1961

 

[Barry1961]

There is something else you can do with software. If you can fix a sensor to a reference point so that it gets actuated at the end of travel you can use it to measure the actual distance. Then offset your commanded position accordingly.

Barry1961