I’ve been unable to get Zoe working in WAP mode with the mid-March release of Jessie. Sometimes the hostapd starts fine, sometimes it doesn’t, and there’s some conflict between configuring the static IP address in the DHCP client config (dhcpcd.conf) and the booting of the DHCP server (udhcpd) – it starts OK according to the boot logs, but by the time I’ve logged in, it’s stopped.
So for now, I’ve dropped back to the end-January image that works, and I’ve stored off a copy of the working pre-WAP mid-March image so I can pick it up another time.
Then I did some tinkering with 0g offsets, measuring them 5 times, then twisting Zoe 90° and measuring again until I had 20 readings. Here’s what it looks like suggesting an X offset of about 40 and a Y offset of about 200 is about right.
So I then took her out to fly several 10s flight including 6s of hover. Some were immaculate, others less so, and the main factors (guess work) are the slope of the ground, and the weight balance, particularly if it shifts in flight because (for example) I’d not got one of the batteries tied down as tightly as possible! Even for the imperfect flights, it was possible to see her successfully stopping the drift, and then the drift started up again, to be stopped again. I think some PID tuning is required here as this suggests the correction is using the P part of the PID and it needs some I.