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Showing posts from January, 2016

My next FPV racing machine...

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Here are some renderings of my latest frame concept. It has a very small frontal area and should reach high speeds. The diagonal motor distance is 210 mm and I will use 5.5 inch propellers (Graupner Race-Prop or C-prop).
















Explanation video: FPV camera tilt compensation

This is a follow up to the previous post on tilt compensation.

I made a video where I explain what FPV camera tilt compensation is needed for, how it works and how it looks like in flight:

https://youtu.be/gXeaINFpvow

In FPV camera tilt compensation, control inputs (RC transmitter --> FC) are transformed to the local frame of reference of the camera.

The control outputs (FC --> motors) may additionally be transformed to the local frame of reference of the propellers (if e.g. the props are tilted or the FC is mounted at an angle - use parameters like 'board align' for control output transforms).

Some thoughts on FPV camera tilt compensation

Almost every 'serious' FPV racer is tilting the FPV camera up in order to have a better image during fast flight. Angles between 10 and 35 degrees seem to be common. E.g. I am using 25 degrees. But tilting the camera with respect to the multirotors horizontal plane has a side effect on the controls (maybe you never thought about it, because you are so used to flying with this side effect).

Just to make the effect easier to visualize: Imagine you drank a beer too much and now you suddenly think you are Charpu, Mr Steele or Mattystuntz. You mount your FPV camera with 90 degrees tilt (pointing up vertically) because your best friend told you that all the pros do it like this. In this case, your roll and yaw control will be interchanged: When you move your RC sticks to roll left, your copter will roll left, but looking through the FPV camera, it appears as if you are yawing to the left! And if you move your RC sticks to yaw left, your copter will of course yaw left, but the image …