SensorsのトピックLow Pass Filter for Angles

Low Pass Filter for Angles

nikivendola — Wed, 15 Jun 2016 16:58:15 GMT

Hello everyone,
I did not understand how to implement the low pass filter described in section 7.2 of the document AN4248.
iLPPSi where it comes from?

I downloaded a compass app on my tablet. Before starting the app tells you to move the tablet following a circuit like the infinity symbol with the screen facing up to eight times. This is to initialize the sensors.

To do the same movements even if you implement the algorithm freescale?

Thanks

Re: Low Pass Filter for Angles

markpedley — Wed, 15 Jun 2016 17:04:54 GMT

The C code for the filter is in the document. It's a single pole low pass filter.

This document has been superceded by the documentation available under click through license at www.nxp.com/sensorfusion.

The figure of eight rotation is required to calculated a magnetic calibration if no calibration exists. If one has been computed it can be stored to non-volatile memory and read from non-volatile memory on next power up.

Re: Low Pass Filter for Angles

nikivendola — Wed, 15 Jun 2016 21:12:33 GMT

Thanks for your answer

The frequency of the magnetometer is 10 Hz. While the accelerometer is sets to 25 Hz.
To calculate V 30 take values from the magnetometer. For you are enough to have adequate correction?

I do not understand what are the iLPPsi values. How to calculate them?
The N for ANGLE_LPF for me would be the 30 values that I take the magnetometer to calculate the Beta?