Linear Hall Effect sensor
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My application is to keep a bot going straight on a walk way. After
studying the issue I think that inertial guidance is my best method.
What I want to do is place small magnets every 10 feet or so to keep
it centered by determining its position with hall effect sensors.
Also using Motormind B on each motor using spcon to insure that it
will travel in a straight line or slowly turn back to the center
depending on the hall effect readout. Has anybody done this? Which
hall effect sensor would you use? Could you use a circuit similar to
the line follower module just substitute the hall effect sensor?
Mark Gillett
studying the issue I think that inertial guidance is my best method.
What I want to do is place small magnets every 10 feet or so to keep
it centered by determining its position with hall effect sensors.
Also using Motormind B on each motor using spcon to insure that it
will travel in a straight line or slowly turn back to the center
depending on the hall effect readout. Has anybody done this? Which
hall effect sensor would you use? Could you use a circuit similar to
the line follower module just substitute the hall effect sensor?
Mark Gillett
Comments
be fairly strong! The linear sensors are very sensitive and drift with
temperature variations. Most manufacturesr use chopper stabilized techniques
to deal with this. You should experiment with these devices before you use
them. They are used when the sensor can be placed very close to the magnet!
[noparse][[/noparse]Non-text portions of this message have been removed]
I have looked at Allegro micro and Panasonic. They both produce them
in an IC. Temperature compensated plus a schmid trigger I am still
looking for a magnet source. The reason I am going in this direction
is that the enviornment is some what dirty with hign ambient light so
IR reflector is problematic. Embedded wire is possible but is hard to
install and produces a perminent path.
In basicstamps@y..., azeasi@a... wrote:
> I have used many different hall effect sensors .... the magnets you
use must
> be fairly strong! The linear sensors are very sensitive and drift with
> temperature variations. Most manufacturesr use chopper stabilized
techniques
> to deal with this. You should experiment with these devices before
you use
> them. They are used when the sensor can be placed very close to the
magnet!
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
linear sensor....if it has a Schmit trigger it is provides a digital output!
If that is what you want you may want to look at the sensitivity. As I
mentioned last time the sensor must be very close to the magnet to get them
to "trip"! If you use a pulsed (38Khz) IR source and sensor you can alleviate
the issues with high ambient light and probably the "dirty environment". If
you are set on using Hall Effect sensors download the aap notes from Allegro!
Good luck!