Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Precise positioning sensors

Status
Not open for further replies.

artem

Advanced Member level 4
Joined
May 22, 2003
Messages
1,350
Helped
126
Reputation
252
Reaction score
32
Trophy points
1,328
Location
Turkey
Activity points
13,461
kender positioning site:edaboard.com

Hello

I need to position or ground a mechanical system during construction. I need a sensor to detect a zero mechanical point. Precision home mechanical switches are available but too costly - 3-5 um repetitive accuracy costs more than 100 Euro .

Actually 10 um precision is affordable . I guess the easiest way to build such is to use LVDS . Since i need to get repetitive result on 1 point LVDS full scale linearity is not of importance. Just i have a problem with finding cores for LVDS . Need Ni(40-60 ) Fe (rest) alloy . May i use ferrite roads for magnetic antennas as LVDS core?

The second alternative is to use quadrant photodiode with laser ligth but it is costly too - Hamamatsu is above 100 Euro per pcs.

Third alternative - electrical contact based on beariong balls . DIY constructions claim 10 um for digitizing probe made with this method .

Any suggestions ?
 

kender

Advanced Member level 4
Joined
Jun 19, 2005
Messages
1,422
Helped
138
Reputation
276
Reaction score
38
Trophy points
1,328
Location
Stanford, SF Bay Peninsula, California, Earth, Sol
Activity points
9,970
Hey, I don't know the direct answer to your question. But I think, you've come across some interesting devices in your search. Could you post links to the datasheets for the 5um accurate switches?

You could also post your question to the group dedicated to sensors: http://tech.groups.yahoo.com/group/sensorforum
 

artem

Advanced Member level 4
Joined
May 22, 2003
Messages
1,350
Helped
126
Reputation
252
Reaction score
32
Trophy points
1,328
Location
Turkey
Activity points
13,461
kender said:
Hey, I don't know the direct answer to your question. But I think, you've come across some interesting devices in your search. Could you post links to the datasheets for the 5um accurate switches?

You could also post your question to the group dedicated to sensors: http://tech.groups.yahoo.com/group/sensorforum

http://sensor.baumerelectric.com/productnavigator/scripts/level2.php?pid=&cat=CONFMechanische_Praezisionsschalter_My_Com&ptk=&psg=myPG|My_Com_Praezisionsschalter&language=en&country=TR&header=Turkey+%2F+Ilke+Otomasyon&orderby=TM_Mech_Familie|asc&restrict=&specialSort=1

repeatability < 0,001 mm
 

Ayman Sharif

Newbie level 4
Joined
May 30, 2008
Messages
7
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,325
Hello
Consider using linear encoder. This type of sensors has steps from 0.1 mm down to 0.1 um.
 

artem

Advanced Member level 4
Joined
May 22, 2003
Messages
1,350
Helped
126
Reputation
252
Reaction score
32
Trophy points
1,328
Location
Turkey
Activity points
13,461
are you about magnetic, magnitostrictive, optical or other types ? Could you please be more specific?

Added after 1 minutes:

It is possible to make ~ 10 um resolution switch based on patented touch probe. For details:

http://www.indoor.flyer.co.uk/probe.htm
 

FvM

Super Moderator
Staff member
Joined
Jan 22, 2008
Messages
48,196
Helped
14,202
Reputation
28,663
Reaction score
12,896
Trophy points
1,393
Location
Bochum, Germany
Activity points
279,212
You never mentioned how many degrees of freedom exist for the object position in your application.
This would be an important condition in selection a suitable sensing principle. Also the opportunity
to have mounting fixtures at one or both involved parts.
 

artem

Advanced Member level 4
Joined
May 22, 2003
Messages
1,350
Helped
126
Reputation
252
Reaction score
32
Trophy points
1,328
Location
Turkey
Activity points
13,461
There is linear guide and ball bearing attached to base and i need to detect motion along one axis with fixture attached to linear guide base. And there is much room to play with it as i have access to mechanical workshop.

Somebody does have information about repeatability (around 5-10 mcirons) of DIY LVDS for minimum output signal for LVDS core based on ferrite cylinder ?
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top