DRO Idea
Posted by
Bill
on 2000-04-18 09:30:02 UTC
I have been lurking and watching all of the ideas presented for making home
made DRO's and haven't seen any one mention the following idea:
Obtain a MR read head from a DAT tape machine, zip drive or some other
similar piece of equipment and use either DAT tape or hi-8 video tape with
the proper recording. Use of 2 tracks would yield quadrature output.
Bandwidth should be no problem so you should be able to achieve 0.0001"
resolution very easily. The use of the MR (magneto resistive) head would be
necessary because of its ability to read flux transitions independently of
speed. Use of standard iron core read heads would require a minimum feed
rate to have a reliable output.
I believe that you can buy 9 track DAT tape heads in qty in the $15.00 price
range, and one DAT tape would supply most of the list members with enough
tape for most applications. It would be necessary to very accurately encode
the tape with the proper bit density and bit / track orientation to provide
quadrature output. The coercivity of DAT tape is very high so the chance
accidental erasure would be pretty slim. The tape and read head would have
to be mounted in some sort of alum track similar to a glass scale and a good
seal would be necessary to keep swarf out.
This is just an idea, if anyone finds it viable, please feel free to take
the idea and run with it! I have only a small working knowledge in this
field and I am not the person to answer all of the questions that may arise
from this idea. I do, however, work with hi level engineers who may be
willing to provide some answers to some questions.
Bill Griffin
www.grifftek.com/links.htm
made DRO's and haven't seen any one mention the following idea:
Obtain a MR read head from a DAT tape machine, zip drive or some other
similar piece of equipment and use either DAT tape or hi-8 video tape with
the proper recording. Use of 2 tracks would yield quadrature output.
Bandwidth should be no problem so you should be able to achieve 0.0001"
resolution very easily. The use of the MR (magneto resistive) head would be
necessary because of its ability to read flux transitions independently of
speed. Use of standard iron core read heads would require a minimum feed
rate to have a reliable output.
I believe that you can buy 9 track DAT tape heads in qty in the $15.00 price
range, and one DAT tape would supply most of the list members with enough
tape for most applications. It would be necessary to very accurately encode
the tape with the proper bit density and bit / track orientation to provide
quadrature output. The coercivity of DAT tape is very high so the chance
accidental erasure would be pretty slim. The tape and read head would have
to be mounted in some sort of alum track similar to a glass scale and a good
seal would be necessary to keep swarf out.
This is just an idea, if anyone finds it viable, please feel free to take
the idea and run with it! I have only a small working knowledge in this
field and I am not the person to answer all of the questions that may arise
from this idea. I do, however, work with hi level engineers who may be
willing to provide some answers to some questions.
Bill Griffin
www.grifftek.com/links.htm