Even though accelerometer is sitting still, numbers jump around?

[espruino-discuss3]

Posted at 2017-06-09 by trusktr

Is this normal?

I have been playing with the MPU6050, but I've noticed that the mpu.getRotation() values, etc, fluctuate a lot even if the accelerometer is completely still. Is this expected?

Maybe the getRotation() values represent a small delta, so they fluctuate from vibrations and/or imprecision?

I haven't figured out how to normalize the value from the four functions in the doc into yaw/pitch/roll, maybe that will be more stable?

(I'm completely new to this stuff, so I have no idea, yet!)

[gfwilliams]

Posted at 2017-06-09 by @gfwilliams

Yes, I think so - how much do they fluctuate by? Have a look at the chip's datasheet - it should have some numbers.

As soon as you start doing stuff with the real world, absolutely everything you read has a percentage error. Often a device will give you more bits of data than it is actually accurate to - because over time you could do some filtering on those values and you might just squeeze a little more out of it.