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Showing posts from November, 2017

Part 2/3: Side force generators - Forces and turning

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About a month ago, I was presenting an idea to make drones faster on race tracks: The so called ‘side force generators’ (SFGs) enable racing drones to drift less during turns, making them potentially faster. The placement of the ‘wings’ is very critical and mentioned in more detail in my earlier post on SFGs. Some people tested the SFGs and confirmed the enhanced flight characteristics. Other people didn’t try and didn’t believe that SFGs could help. I must agree that the concept of the SFGs is not so easy to understand. That is why I will explain it in more detail here.



Let’s start with something that everyone knows (figure 1). When you are going through a fast turn with your car, then your car needs to provide two forces to stay on the track (grey line): The ‘thrust’ (green) of your car needs to equal its aerodynamic and friction drag (yellow). When the car turns, then there needs to be a constant force towards the centre of the turn, called ‘centripetal force’ (red). This force is …

Winter preparations: Recoil stretch

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This design was just finished, I am still searching for the perfect propellers. The performance is very good already, but the props are not durable enough. The MTM is 150mm, I noticed that quads fly cleaner and with less noise when there is some extra space between the propellers.

Here is my setup
Recoil stretch frame, 2.5mm carbonWeight without Lipo: 80gTake-off weight: 135gAMAX inno 1105 4000 kVEmax Bullet 12A ESCsTattu 4S 450 mAh 75CRuncam Swift micro NTSC, 2.1mmFXT FX806T VTX, 25 mWFrsky R-XSREmax femto (still my favorite FC although I haven't tried many)XT 30AMAX inno 3030 3-blade props











CAD design, manufacturing + test flight of an FPV racing airplane

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I wanted to create a small FPV racing aircraft that has a good performance on small racing tracks with FAI gates. So I created this bimotor airplane. The yaw control makes it very agile. I am using a flight controller with iNAV firmware to stabilize all axes.
The aileron servos are much too slow (0.1s/45°), so it was hard to tune. They will be replaced now with faster ones (0.05s/60°).
Propellers are 4 x4.5 inch, motors are xnova 1407 - 3100kV, Lipo is 1Ah, 4s.
I like the results, and I am looking forward to fly it on race tracks with a lot of gates.
Watch this video to see a timelapse of the design and milling process, followed by some inflight clips: