Information on digital angle gauge.

[Les Jones 1Participant @lesjones1]

Hi Michael,
The space between the PCB and the front cover is 3.97 mm and there would be room for a square with about 7 mm sides. The smallest switch I have in my junk box is about a 6 mm cube plus the plunger. It is one of the push push type so it would require some kind of guard round the plunger to prevent it accidentally being switched on. If a switch could be found with the same footprint as the push buttons it is easy to cut the tracks so it could be inserted into the board.

Les.

[Les Jones 1Participant @lesjones1]

Hi Involute Curve,
I have not seen one of these devices. I see no reason why they should not be used for this purpose. am I correct in assuming that there are 5 encoders in the arm assembly ? The software most do some pretty clever trigonometry. to convert these angles and arm lengths into X, Y, Z coordinates. ( I assume the arm lengths are fixed.)
The interface I have designed to be used with "Yuriy's Android tablet DRO" has 4 inputs and with some changes to the software should be able to output the data in a suitable format. It should also be possible to add support for a fitht channel by using a processor fraom the same family but with more I/O pins.
You can sometimes find encoders on the end of motors in printers etc. The problem is that some have strange numbers of lines. When I first started to fit a DRO to my milling machine I found an encoder from an HP printer that on my first test looked like it was 500 counts per rev. After fitting it I found the reading were not correct. It turned out it was 504 counts per rev.

Les.

[Involute CurveParticipant @involutecurve]

Here's a link to the page I read

http://www.cnczone.com/forums/digitizing-laser-digitizing/4424-digitizing-arm-options.html

Shaun

[Neil WyattModerator @neilwyatt]

> It turned out it was 504 counts per rev.

You can imagine the designer sniggering "This one will fox the skip-monkeys!"

Neil

[Les Jones 1Participant @lesjones1]

I have found out that I made a mistake with the original information I gave about the angle gauges. I was 1 bit position out. This is the corrected information.
I have found that 256 counts corresponds to 5 degrees so one count is 0.01953125 degrees. Bits 0 to 8 count the number of 0.0390625 degree units. Bits 9 to 23 count the number of 10 degree units. There will be 18432 counts per revolution. Bit 23 is used as a sign bit so the counter will overflow at a value of + or – 8388608 counts. This corresponds to 455 revolutions plus 40 degrees. I think this will mean that when the count overflows the readings will be wrong. (Unless the display board does some clever maths.)
I now have my interface to "Yuriy's Android DRO" reading data from the angle gauge and displaying on my Nexus 7 tablet. I have not yet put in code to subtract 360 degrees for each full revolution,

Les.

[Les Jones 1Participant @lesjones1]

Hi all,
I have updated the information on my website about the "Wixey" type angle gauges. I have also added a design for an interface to allow the output to be displayed on "Yuriy's Android tablet DRO"

Les.

[Michael GilliganParticipant @michaelgilligan61133]

Thanks, Les

MichaelG.

[Nathan BrawnerParticipant @nathanbrawner91618]

Hello Les, I am looking to display my Wixey angle gauge on either an LCD or display on my laptop for a project. Any advise on how to get started with deciferring the data? I don't have much experience with data as I have just began to study it. Thank you for any help provided.

-Nathan

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