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The flying rectangle.

A video to show that even the simplest of air frames will carry the Temarai gimbal.
This wing is made from 50mm thick EPS foam rectangles stuck together with duct tape (cloth tape) and hot melt glue. Only the leading edges have been rounded using sandpaper.

The 2 things you need for a balanced flight are:

  1. Adding or removing nose ballast to approximately fly flat and
  2. Setting the AOA (Angle of Attack) using the control surfaces (usually 6-7 degrees).

All the red plastic parts you see on this plane are available on this site. The motor mounts aren’t up yet, but will be soon.

The control surfaces are 5mm foam board available from sign writing supply shops.

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2 axis inline (possibly) aerodynamic head tracker gimbal

Currently working on making this 2 axis head tracker gimbal. Roll is not necessary. It it optimised for FPV slope soaring (gliding). We want it to ultimately sit under an aerodynamic cowl so most of the bumpy edges are not in the air stream. Also both rotation points have their own bolts so that load on landings are not transferred through the servo mechanics as much. This design is for the Runcam Eagle Pro 2.

It’s designed for standard Corona 939MG servos, simple linkage stoppers and galvanised 1.8mm – 2mm fencing wire for pushrods.

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Dubious GY-85 boards and HMC5883L fix

I ordered 3 different GY-85 boards from 3 different suppliers to find that all of them had the wrong magnetometer in them. Some even advertised their product with the HMC5883L chipset on them, but when they arrived they where the QMC5883L chipset.

After all this effort to find something without the shipping cost / time from the USA I decided to just get the HMC5883L individually and attach it to the I2C bus of the GY-85 board. The individual boards is called the GY-271. I found this supplier in Chullora in Sydney:
GY-271 HMC5883L
It worked just fine and now the head tracker is working.
You’ll see in the image below that the Honeywell HMC5883L chip is defined with the markings
L883
2133

Where as the 6th page of the QMC 5883L manual shows the markings something like
DX
5883
XXXX

QMC5883L datasheet

HMC5883L datasheet

Using the GY-271 compass board by itself

(Also posted in RC groups)