Can an accelerometer be used to determine when an rotating automotive wheel is pointed toward the ground ?

[MHoll]

I assume it will take a Gyroscope as well due to the rotation forward motion. A Gyroscope is

however expensive in the automotive temp range. Can it be done with 2 Accelerometers ?

[S.Ma]

The triple axis accelerometer will give you the gravity vector.

Filtering and wheel under rotation at high speed will make the filtering and instant reporting challenging.

Running at 200km/h vs max Accelerometer samples per second and defactor the speed variations (brakes/speed up)...

[MHoll]

Ok, Thanks for the reply. It actually will be for a tractor wheel application so the speeds will be lower with larger wheel size.

[AvaTar]

Generally, you can check out INS (inertial navigation system) examples and algorithms to determine such parameters.

Tractors mostly go relatively slow, but sometimes on quite slanted terrain.

I know of some cases when the driver underestimated the terrain angle ...

[Eleon BORLINI]

hi mike, theoretically it's possible to use the axl stand alone for understanding the position of the wheel, but, as kic pointed out before, it's unpractical due to the complexity of the filtering you have to apply to raw data to select the rotating wheel pattern. For this reason, I would suggest you to use a 6 axis sensor (axl+gyro) such as the LSM6DSO(X), which has and embedded gyro that enables you to directly measure the rotating speed (and costs less then 4€ and has also an embedded FSM to enhance your filtering capabilities), or an L3GD20H which costs little less but it's an only gyro. Regards

[MHoll]

Yes the LSM6DS0(X) part would be the part to use but the dilemma is the environment the product will be in, the max wheel rim temp will be +100 C . The LSM6DS0(X) is only rated to +85C.

[S.Ma]

Find an industrial grade part, maybe it could sustain +125C...

[Eleon BORLINI]

​I would suggest you the automotive grade (up to 105°C) 6-axis module ASM330LHH

https://www.st.com/content/st_com/en/products/mems-and-sensors/automotive-sensors/asm330lhh.html

Regards

[MHoll]

Yes, the ASM330LHH looks good for this, thanks.