5 ms·

I used a Hall Effect sensor on my robotics team and it caused nothing but issues. We were using it to PID our motors to be the same speed. I think there might’v

by sakras 4y ago

I used a Hall Effect sensor on my robotics team and it caused nothing but issues. We were using it to PID our motors to be the same speed. I think there might’ve been some kind of interference from the motors, but I’m not sure. We ended up switching to an optical rotary encoder and all of our problems went away. Given my bad experience, reading that they’re so popular really surprised me. Are they actually finicky or did my team just do something wrong?

marcosdumay 4y ago
They seem to work incredibly well when everything is made of plastic, and incredibly badly when everything is made of steel. What is quite reasonable. If you go to a gym, try to keep track of your exercise counts and compare them to the machine counters. The machines almost never get them right. But for keyboards they seem to be pretty great.
retSava 4y ago
Halls depends on magnetic fields. Motors generate magnetic fields to a large degree, hence electromagnetic interference handling becomes important in those applications.
fest 4y ago
Many brushless motors (fans, electric scooters) have digital output (i.e. on/off) hall sensors triggered by motor magnets to read a coarse motor's shaft (to know which coil should be energized). There is even a higher resolution approach of using two or three analog output hall sensors sensing motor magnets to read fine stator position (for example, gimbal motors for DJI drones use this technique). Then there are ICs that contain several hall sensors that are arranged to measure absolute angle of diametrically magnetized target (these are the one's used in hall effect potentiometers, and I've seen them used for position feedback in brushless motor control). So, most likely your project had an issue with sensor placement, or the sensor wasn't correctly selected for the application They are no more finicky than IR sensors reacting to sunlight, or just about every type of sensor *also* being a temperature sensor: you have to be aware of what exactly is the sensor measuring and how the environment may affect it's measurements.

by sakras 4y ago

marcosdumay 4y ago

They seem to work incredibly well when everything is made of plastic, and incredibly badly when everything is made of steel. What is quite reasonable. If you go to a gym, try to keep track of your exercise counts and compare them to the machine counters. The machines almost never get them right. But for keyboards they seem to be pretty great.

retSava 4y ago

Halls depends on magnetic fields. Motors generate magnetic fields to a large degree, hence electromagnetic interference handling becomes important in those applications.

fest 4y ago

Many brushless motors (fans, electric scooters) have digital output (i.e. on/off) hall sensors triggered by motor magnets to read a coarse motor's shaft (to know which coil should be energized). There is even a higher resolution approach of using two or three analog output hall sensors sensing motor magnets to read fine stator position (for example, gimbal motors for DJI drones use this technique). Then there are ICs that contain several hall sensors that are arranged to measure absolute angle of diametrically magnetized target (these are the one's used in hall effect potentiometers, and I've seen them used for position feedback in brushless motor control). So, most likely your project had an issue with sensor placement, or the sensor wasn't correctly selected for the application They are no more finicky than IR sensors reacting to sunlight, or just about every type of sensor *also* being a temperature sensor: you have to be aware of what exactly is the sensor measuring and how the environment may affect it's measurements.