Re: Inductsyn
Posted by
Arne Chr. Jorgensen
on 2000-03-17 10:24:42 UTC
Inductsyn:
-------
Jon wrote:
We don't have to debate this - my point was that the linear strip,
or primary, is not critical to make. This is not sensitive to voltage drops
along the "strip" or stability of the voltage source.
I think you focus on the end part of the sensor electronics, and that is
something else.
Thanks for the info about the datasheets. If I come across them, I'll have a
look, but it is very clear that you know what I am talking about, so - what
is your verdict ?
Do you think this could be a candidate for a DIY DRO ?
Mitutoyo digital vernier:
---------------
I am blank on this one. ( there is nothing on the backside of the strip ? )
Is i possible to dig up some more info on how this might work ?
Sensors using bearing balls in a tube:
-------------------------
Same as above, more info.
In closing:
------
It is very clear that a lot of systems don't use optical reading, and why ? I
think some of these other systems would be better. There is "hundreds" of
possible ways to make a DRO, but only a few % of them would work out in this
context.
I would just end with a few words about the "inductosyn" : I have said that
they used a system like this on some old IBM printers. I just had a short
look at one, years ago. But the sensors was not very close to the strip
( 0.1-0.2" ) and there was some spill. Take this together with what I tried
to tell Jon, - I think you could get a home-made system work well.
There is difficulties with everything, but the objective is to solve the
linear ruler problem. If you could make them, mount them, and have a decent
accuracy, - then this should be the main thing. Maybe the electronics is a bit
more complicated, - but that should be easier to solve.
To put it into other words: I would rather pay something more for a sensor I
could use with something I could mount and fit myself, then buying a very
expensive scale and use home-made electronics.
We have mentioned a few different systems, is it possible to dig up some more
info of some practical designs ?
//ARNE
-------
Jon wrote:
>> It is not sensitive to voltage, but phase.Well, - yes and no :)
>No, the amplitude varies sinusoidally with position, and the phase flips
>as the signal goes
>through the zero. You need the amplitude of both pickups to
>interpolate, because the
>winding pitch (equivalnt to the grating pitch on an optical encoder) is
>fairly coarse.
We don't have to debate this - my point was that the linear strip,
or primary, is not critical to make. This is not sensitive to voltage drops
along the "strip" or stability of the voltage source.
I think you focus on the end part of the sensor electronics, and that is
something else.
Thanks for the info about the datasheets. If I come across them, I'll have a
look, but it is very clear that you know what I am talking about, so - what
is your verdict ?
Do you think this could be a candidate for a DIY DRO ?
Mitutoyo digital vernier:
---------------
I am blank on this one. ( there is nothing on the backside of the strip ? )
Is i possible to dig up some more info on how this might work ?
Sensors using bearing balls in a tube:
-------------------------
Same as above, more info.
In closing:
------
It is very clear that a lot of systems don't use optical reading, and why ? I
think some of these other systems would be better. There is "hundreds" of
possible ways to make a DRO, but only a few % of them would work out in this
context.
I would just end with a few words about the "inductosyn" : I have said that
they used a system like this on some old IBM printers. I just had a short
look at one, years ago. But the sensors was not very close to the strip
( 0.1-0.2" ) and there was some spill. Take this together with what I tried
to tell Jon, - I think you could get a home-made system work well.
There is difficulties with everything, but the objective is to solve the
linear ruler problem. If you could make them, mount them, and have a decent
accuracy, - then this should be the main thing. Maybe the electronics is a bit
more complicated, - but that should be easier to solve.
To put it into other words: I would rather pay something more for a sensor I
could use with something I could mount and fit myself, then buying a very
expensive scale and use home-made electronics.
We have mentioned a few different systems, is it possible to dig up some more
info of some practical designs ?
//ARNE