I took Zoe outside (temperature 0°C – freezing point) to fly this morning with fusion enabled to see what the effect was – fusion was disabled in the flights; they was purely for compare and contrast of the two independent sensor sources.
Fusion was a complementary filter with the -3dB crossover set to 1s.
In all graphs,
- blue comes from the Garmin LiDAR (Z axis) or Camera (X and Y axes)
- orange comes from the accelerometer with necessary subtraction of gravity and integration.
- grey is the fused value – orange works short term with longer term fusion with blue.
In general, the shapes match closely, but there’s some oddities I need to understand better:
- horizontal velocity from the Camera is very spiky – the average is right, and the fusion is hiding the spikes well – I’m assuming the problem is my code coping with the change of tilt of the camera compared to the ground.
- the vertical height is wrong – at 3 seconds, Zoe should be at 90cm and leveling out.
I need to continue dissecting these stats – more anon.