and yet, amazing.
So in that last video of a ~10s flight, Phoebe drifted about 1m when she shouldn’t have. To me, that’s amazing; to you, that may be underwhelming. So here’s why you should be amazed. Basic school math(s):
distance = ½ x acceleration x time² ⇒ plugging in the numbers above says she was accelerating at 0.02m/s² (2cm/s²) instead of zero to travel 1 meter in 10 seconds.
Gravity is roughly 10m/s². The accelerometer is set to read up to ±4g. So that’s a range of 8g or roughly 80m/s²
So 0.02/80 * 100 = 0.025% error or a ±8 error value in the sensor range of ±32768.
Now the critical part – the sensors are only rated at 2% (±655) accuracy, and yet I’m getting 0.025% or 80 times that degree of accuracy.
And that’s why I don’t think I can get things very much better, whatever I do.
There is a slight chance that when the A2 is released (sounds like that’s shifted to next year now), I may be able to run the sampling rate at 1kHz without missing samples (I’ve had to drop to 500Hz to ensure I don’t miss samples at the moment).
Other than that though, she needs more sensors:
- camera for motion tracking (!blind)
- ultrasonic sensors for range finding (!deaf)
- compass (!disorientated)
- GPS (!lost)
- altimeter (!scared of heights).
but they’ll also need an A2 for the extra processing. So this is most definitely it for now.