Nonlinear sliding motion stage

[Rolly]

Hi,

I would like to know where I find companies offering nonlinear sliding motion stage with motorized controller? There are a lot of linear stage on the web, but the thing I need is similar except the stage table moves in an curve? Rotary stage is not a good alternative since I only need motion of +-45 deg from the center.

Thanks very much

[Buechsenschuetz]

What you are looking for usually is referred to as 'goniometer stage'. I found a link to a company making such devices:

http://www.micos-online.com/WT_120.html

Manually driven goniometer stages are available from Edmund Optics, such as #L55-838. The items available from Edmund optics have +/- 20 deg tilt range only.

[Jochen]

I know Micos very well and they also provide direct connectivity to NI motion control boards.Goniometers have a fixed radius. For the case that you need a flexible solution with variable radii a hexapod (e. g. available from PI) could do the job but this solution might be a bit oversized



Best regards,

Jochen Klier
National Instruments Germany

[Buechsenschuetz]

There are many solutions for this problem, and there is one (probably oversized, too) available from our company, the 'open Eulerian cradle'. It is originally designed for sample positioning in crystallographic equipment but think it might be suitable for other applications, too.

http://www.stoe.com/pages/brochure/sampleholders_brochure.pdf

[Rolly]

Hi,

Thanks for your information but I should have made myself clear, please have a look.

Thanks.

[Buechsenschuetz]

I see... THK makes linear, curved and combined linear-curved guide rails but usually they do not supply the drives.

http://www.thk.com/technical/seihin_en.html

Of course it is not possible to drive a non-linear guide stage with a worm gear (spindle). We are using THK's curved guide rails for a similar application (positioning of a read-out head on a semi-circular track) and had to design our own drive, using a stepper motor and a belt drive, plus numerous rollers to guide the belt around the curved rail.

I am afraid there is no off-the-shelf solution for your problem but I think a consultant or a company with some experience in specialised mechanical design could help you.

Another approach would be a linear motor on a curved guide. There are companies making these devices but they are quite costly.

[Jochen]

Another simple solution could be a xy-table running arc moves but of course it depends on your application if this is an option or not. The major disadvantage of the xy-table is of course the increased amount of space required.
Even if you can't find such a stage in the standard product catalogs of Micos and PI it still might be a good idea to contact these companies as they both can provide customized stages, too.

Jochen

[Rolly]

hello Buechsenschuetz ,

Could you please help me to identify the model of THK for your application, there are too many of them and I am not sure which to look at. Is it the R Guide HCR you are using?

Thanks a lot,

Rolly

Message Edited by Rolly on 07-27-2005 06:45 PM

[Rolly]

Hello Jochen ,

Thanks and I have thought of that but it is not so economical.

Rolly

[Buechsenschuetz]

You already found it, the HCR guides might be suitable for your application. However, you still need a drive but a mechanical engineer will be able to help you.