Position sensor: Hall, AMR, GMR, or TMR
I need a position sensor, starting looking into Hall effect sensors, and then found all this info on AMR, GMR and TMR sensors and the articles describe these sensors as having better sensitivity (up to 20x) , lower power consumption, and more stable.
What would be best for an Arduino project and/or positioning actuators ?
Thanks
Sid.
What would be best for an Arduino project and/or positioning actuators ?
Thanks
Sid.
ste5an
The question is meaningless as "best" needs a comparison to something. Without knowing your requirements, this is impossible. E.g. the 20 times more precise sensor may require 20 times more power exceeding your power available.
ASKER
Size: Small, probably about the size of a standard transistor or chip.
Power: Low, the device is portable and run off 'AA' batteries. So voltage < 6 and Amperage < 50 mA
Sensitivity: Be able to detect a magnet w/in 1/4" in proximity.
Thanks
Power: Low, the device is portable and run off 'AA' batteries. So voltage < 6 and Amperage < 50 mA
Sensitivity: Be able to detect a magnet w/in 1/4" in proximity.
Thanks
ASKER CERTIFIED SOLUTION
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ASKER
Dave, as always, thank you for the suggestion.
I was able to find some on Amazon as well as Newark. I will order a handful for a few dollars, test them out and post back.
Thank You.
Sid.
I was able to find some on Amazon as well as Newark. I will order a handful for a few dollars, test them out and post back.
Thank You.
Sid.
Just a few questions:
- What are you making?
- What is the object that is moving? A print head or valve seem?
- What is doing the moving? A motor or you hand?
- How many axes or dimensions? One, two, three, or more?
- How much does it move? 1, 2, or 10 inches?
- How much information about the position do you need?
ASKER
- What: Small turntable
- Mover: Stepper Motor
- Axes: 1
- How much: 360 Rotation
- Info: Just find a home position, all other positions will be calc'ed from stepper movement.
If you are just looking to find the HOME position on a turntable, then any digital output sensor should work:
any of the magnetic sensors, or an optical sensor, or even mechanical limit switch.
If you are using a 200 steps per revolution motor and direct drive, then HOME may larger than one step. So you need to define HOME as the edge of the sensor transition. You you have to be careful of the motor direction.
any of the magnetic sensors, or an optical sensor, or even mechanical limit switch.
If you are using a 200 steps per revolution motor and direct drive, then HOME may larger than one step. So you need to define HOME as the edge of the sensor transition. You you have to be careful of the motor direction.
ASKER
I had anticipated writing some code to first find the edge of the home position and then approach it slowly from both directions and then calculate the center of 'home'
Thank you for the help and suggestion.
Anything else you can add is appreciated.
Thanks
Sid.
Thank you for the help and suggestion.
Anything else you can add is appreciated.
Thanks
Sid.