CF props and near zero G

So I’ve finally worked out why Zoe doesn’t work with her carbon props.  2 factors:

  1. I’ve been using a hard take-off surface outdoors rather than the wet, soggy lawn.  This means that while the blades are winding up to hover speed, Zoe’s legs are imperceptibly bouncing up and down on the hard surface.  An upwards force from the blades is smooth, but as a leg hits the hard surface, the hard deceleration is picked up by the accelerometer as near zero or negative G.
  2. I’d still got the near zero G protective code in place, not recognising the near 0 G does happen when impacting with hard surfaces .

Hence the vertical velocity integration was ommitting the low or negative G forces, meaning the vertical velocity was showing much higher rates than expected, so the code wound down the prop speeds to slow down the perceived ascent.  Hence she never got off the ground.

Moving her to the saturated lawn and removing the protective code filtering out near 0G readings meant she finally took off.  She was very unstable but she took off.

So more physical buffering is required – I’ll be attaching sponge balls onto her feet to soften the hard impacts.  At the same time I have some softer (I think) foam pads coming too for attaching Zoe’s HoG to the frame.  Finally, I need to get her off the ground as quickly as possible rather than faffing around bringing her props up to speed in a nice controlled manner.  Oh, and I need to get her off the ground ASAP.

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