I may be the last to the party. 250mm quadcopter frames are sooo last year. With advances in flight controllers, flight control software, motors, ESCs and batteries, smaller copters are now all the rage. 210 seems to be the current best trade off in size vs performance for a miniquad toting a GoPro sized camera.
So, it’s go time on a 210 for me. A friend and flying buddy recommended picking up a QAV210 clone. That matched what others were saying (and loving), so I did.
Clone. Why a clone? Ugg, I know. I’m evil too, right? A couple reasons…
Money. Almost everyone comments on how expensive the original manufacturers’ quadcopters are. They’re really nice, but you pay extra for them. You should though, right? Designers and testers spent countless hours honing a design. When someone sells their own that’s very similar, it can hurt the original designers and innovators. We should support them. Really, we should. I didn’t.
Business research. I recently started my own online hobby store called Rotorland (currently selling multirotor stuff through Amazon), so I wanted to see what the quality was like of a recent Chinese-made carbon quadcopter. This quad now sells for about $27 on Amazon. It looks better than I expected. Quite nice, actually. Time will tell how it holds up to crashes, but it looks good so far.
Alright, so what do I put in it? I originally planned to use a set of Cobra 2204 2300kV motors I already had. Again for business research, I wanted to try something that I could sell. Emax RS2205 “red bottom” motors are the new hotness – everyone raves about them.
I also wanted to try a power distribution board (PDB) with current sensing. Previously, I’ve managed my battery usage by a timer or the flight controller voltage sensor (vbat). For this quad, I wanted to know how many mAh I’ve used. I’m hoping this will let me get some more flight time (because I typically land early without one) and help me treat my batteries a little better.
I decided to go with ReadError’s Brotronics UberDistro. I bought mine before version 2 came out, but the v2 PDB (mk2, actually) has both a 5 and 12v output along with voltage and current sensor outputs. It’s a really nice PDB built with 4oz copper, so it’ll handle the load just fine.
I chose to go with the 90A version. Both the 90 and 180 are the same board except for the output range on the current sensor. The 90A PDB outputs roughly 3.3V at 90A. Since I’m feeding the current input straight into a Micro MinimOSD (for FPV heads up display goodness), which can take up to 5V input, the 90A UberDistro will work great for me up to about 136A. So, I just need to stay under about 34A per motor. No problem.
I put the current sensor readout right in the middle of the screen on my OSD. I put the battery voltage on the left and the flight timer on the right.
I 3D printed a camera mount for a Xiaomi Yi. It’s light weight and seems to hold the camera fine, with the help of a zip tie.
Above the UberDistro PDB, I mounted an ImpulseRC Cyclone flight controller. With the help of Boris’ Betaflight, the Cyclone is one of the best miniquad flight controllers at the moment.
Full price, high end electronics with a cheap frame. You can see where my priorities are.
I went with Little Bee 20A ESCs, again because they’re something I’m considering selling in my store. For now, they’re loaded with BLHeli, but they might get Multishot in the future.
I’ve had great luck with Lumenier batteries in the past, so I bought a handful of their 4S 1300mAh 60C batteries. Of course the day after I bought them, they released their graphene batteries. So, I bought some of those too.
I went with the new FrSky XSR receiver. It’s tiny and does SBUS. It should be great, but more on that after I fly it for a while.
TS5823 video transmitter. Nothing special there.
I’m running Betaflight 2.7.1 at 4kHz with 2kHz ESC commands, airmode and all its other goodness. I plan on trying different looptimes later. The Cyclone can do up to the full 8kHz looptime without a problem…at one with the gyros.
So, here she is. I did a couple quick driveway hover tests. I had to tweak some OSD settings, but it’s now ready for a proper maiden flight.
Ready to fly (with the big HD camera and battery), it weighs 590g. With the Emax 2205 motors putting somewhere around 1200g of static thrust each, the thrust to weight ratio is around 8:1. That should make for a seriously fun quadcopter.