Test Descriptions

32

Freescale

Sensor Fusion Library for Kinetis MCUs, Rev. 0.7, 9/2015

Freescale Semiconductor, Inc.

5.6 Orientation Static Noise

5.6.1

Intent

RMS noise as a function of orientation for a motionless DUT.

5.6.2

Procedure

This can be based upon data gathered for the orientation static drift test. The classic standard deviation

equation is used to compute the metric/value.

5.7 Orientation Dynamic Drift

5.7.1

Intent

Measure of the ability of fusion code to return to a known orientation after movement.

5.7.2

Procedure

Setup as defined in Matlab Stimulus/Expected Response + Hardware-based Fusion and in Figure 9.

Matlab is used to post-process data.

1. Precondition the DUT by executing magnetic calibration trajectory leaving DUT in a given

orientation.

2. Keep DUT in a given orientation motionless for 2 seconds.

3. Rotate DUT at 0.5 revolution/sec for 10 seconds around vertical axis.

4. Keep DUT in its last orientation motionless for 2 seconds.

5. Determine the initial orientation by averaging orientation samples from the initial motionless period

and the final orientation by averaging the samples from the final motionless period. The difference

between the two orientations is the orientation dynamic drift.

6. Repeat steps 1-5 for all six major orientations of the development board.

5.8 Maximum Angular Rate

5.8.1

Intent

This test determines the maximum rotation rate for which the filter is able to correctly track orientation.

5.8.2

Procedure

Setup as defined in Matlab Stimulus/Expected Response + Hardware-based Fusion. Matlab is used to

post-process data.

1. Rotate DUT around X axis five times starting at rotation rate 360 dps.

2. Plot the ideal simulated orientation together with the orientation samples calculated by Kalman

filter fusion algorithms: 9DOF and 6DOF Accelerometer + Gyro and notice if fusion data tracks the

ideal orientation.

3. Increase the rotation rate by 360 dps and repeat steps 1 and 2.

4. The highest angular rate at which the fusion algorithm orientation still tracks the ideal simulated

orientation is the maximum angular rate.