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using hall effect sensor for rpm detection

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meisterpro
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using hall effect sensor for rpm detection

Hi Everyone!

In my setup, I have some gears and differentials so e-rpm does not reflect the actual rpm I get from the shaft. I have a hall effect sensor to get the actual rpm value from the wheels. Do you have any idea how or if I can feed that value back to VESC 6 MkV. I want to see the relation between erpm and actual rpm and if the relation is somehow not linear, I want VESC to calibrate PID controller using the actual rpm.

I think the Hall Effect sensor pins on VESC 6MkV are for detecting motor position. I would love to use one of these pins to feed my actual rpm value to VESC. But, I am not sure if that is even possible. Does anyone have any idea to make it possible?

Thank you in advance.

vadicus
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Joined: 2018-08-17 07:26
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The code is already using hall sensor signals (in hall sensored mode) to track the motor rotation, so if you enter your poles, wheel diameter, and gear ratio correctly, you will get pretty accurate wheel RPMs, speed, and distance. The ony time when this accuracy will be affect is when you change any or all of the same parameters: poles, gear ratio, wheel diameter. It's unlikely that your wheel diameter or poles will change, at least, not until you change the motor or the wheel size. The gear ratio would change if you have a transmission. If you do have a transmission, you can either communicate the specific gear ratio every time you switch gear or you can have a hall (separate from the motor) installed on the wheel directly and feed that signal back to any available pin on the MCU. You would also need to modify your code to pick up the wheel RPM rather than motor RPMs for speed, distance, effeciency and other calculations.