Help building a 1s/2s drone hybrid

Build Log
1

Hello Everyone!

I am looking to build a drone that works well on 1s so I can fly inside and 2s so I can fly outside with a little more power. I did some research on these parts but I want to ensure they will work together. Below is my build:

Motors: racerstar 802 15000kv (Racerstar BR0802 0802 15000KV 19500KV 25000KV 1-2S Brushless Motor 1mm Shaft for Sale - Banggood USA-arrival notice-arrival notice)

Frame: 65mm (https://www.amazon.com/Betafpv-Beta65-Brushless-Upgraded-Brusheless/dp/B078GLW4HK)

Top of Frame: Mobula7 Canopy (https://www.banggood.com/Happymodel-Mobula7-Part-V2-Angle-Adjustable-Camera-Canopy-for-RC-Drone-Caddx-EOS2-Camera-p-1415957.html?akmClientCountry=America&rmmds=cart_middle_products)

Flight Controller: URUAV Crazybee F4 PRO V2 Flight Controller (https://www.banggood.com/URUAV-Crazybee-F4-PRO-V2-Flight-Controller-Compatible-Frsky-Flysky-DSM2DSMX-Receiver-for-UR85UR85HD-Whoop-FPV-Racing-Drone-p-1464583.html?akmClientCountry=America&rmmds=cart_middle_products&ID=566266&cur_warehouse=CN)

Camera: Caddx Turbo EOS2 (https://www.banggood.com/Caddx-Turbo-EOS2-1200TVL-2_1mm-160-Degree-13-CMOS-169-Mini-FPV-Camera-NTSCPAL-For-RC-Drone-p-1278882.html?akmClientCountry=America&rmmds=cart_middle_products)

Camera vtx: Happymodel Mobula7 Upgrade (https://www.banggood.com/Happymodel-Mobula7-Part-Upgrade-Whoop_VTX-5_8G-40CH-25mW200mW-Switchable-VTX-for-RC-Drone-p-1406943.html?akmClientCountry=America&rmmds=cart_middle_products&cur_warehouse=CN)

DVR: HGLRC DVR Nano (HGLRC DVR NANO Mini Video Recorder Support Record Playback SD Card For FPV Camer Sale - Banggood USA sold out-arrival notice-arrival notice)

If anyone has any good/bad experiences with any of these parts I would like to hear about it. I am also interested in the range of the FC. Should I just get a cheaper FC and get a seperate tx?

Thanks,
Phil

2

I think most of it will be fine, but you will probably find it will be cheaper to rather go directly for the mobula7 BNF kit directly. YOu get all the same parts and you will end up needing to rebuild it at some point anyway. Also pretty much all of the racerstar/URUAV gear is just rebended from happymodel anyway.

As for your plan on flying 1s an 2s the mobula7 can do this, but in my opinion on 1s its too underpowered to do acro flying… but its good enough for gentle cruising indoors.

My suggestion would be to rather just go for the mobula6, it is newer and although 1s it still has loads of power plus the batteries are faster to charge and it flies like the mobula7 on 2S anyway as it weights just 20g. I actually just published a review of the mobula6 if you wanted to have a quick read.

3

That’s for the response! I read the review and the mobula6 seems awesome. Does it actually fly on 2s? I didn’t believe the 19000kv motors were rated for 2s?

4

I’ll try to convince you to go with a proper 1s build since it’s winter and you likely won’t fly much outside anyway. for another couple of months and there’s a lot of compromises you’d have to make if you wanted a hybrid. 1s is all about minimum weight (the parts you listed would barely take off on 1s :smiley:) and with 2s you want better camera/VTX/RX because you will fly faster and further. You will also want more durability for 2s because it will carry much more momentum in crashes.

Haven’t tried them personally, but I’ve seen them recommended by people I trust (afaik these are not a rebrand of HappyModel motors), but 15000kv won’t really work on 1s unless you go mental with keeping weight down (~15-16g max + quad-blade props would work). I’d go with 19500kv which is optimal for 1s and then use a throttle output limit of about 60-70% when flying it on 2s.

That’s definitely the one you want to go with if you really want 2s hybrid as it’s the most durable one. You might need to get creative with battery mounting for 2s though, but they also have a 2s version that accepts 2 x 1s stick batteries. It’s not bad for 1s but there’s a better (lighter and higher battery placement for better CG) and newer option, also from BetaFPV - Meteor65 frame.

It’s an awkward solution for the triangle-shaped VTX and a EOS2 camera neither of which are that great. More about that under camera.

I’m very biased against Crazybees because I haven’t had a single one out of ~15 last more than ~5 flights. BetaFPV is the way to go in my opinion. They have a great new 1s-only board at 2.67g which has proven super reliable so far in several builds over last couple of months for me so I would whole-heartedly recommend that but obviously it won’t work if you really want 2s.

While it has a nicer picture than most whoop AIO cameras in perfect conditions, it’s really bad at light handling and is very prone to jello at sunlight. In my opinion not worth its weight - if you want to focus on 2s then RunCam Nano 2 is a much better camera. If you go 1s, then get any AIO camera/VTX and depending on which one you get, that will influence your choice of camera mount and/or canopy. The best of the best is FX950TW which comes with a 3d printed mount and if you want extra protection then a clear TW Razor Skin canopy has proven the toughest. Most other cameras will fit into NBD beeeye mount (some cameras might require cutting the mount a bit) but be careful with AIOs which have antenna sticking up, you will probably want to secure those additionally.

Hell for mounting. You want to keep the profile as low as possible and this one will require at least 5mm extra height. You want something tiny that you can stick inside the canopy or underneath the fc. BetaFPV has a new AIO that doesn’t have the best camera (they aren’t really known for making good cameras), but I am seriously impressed with its VTX performance. It comes with two mounts and you can use a BetaFPV canopy for extra protection if needed (those break easily, but you can get 5-packs via AliExpress for peanuts - get clear ones as those are toughest). Here’s an example video feed from this VTX vs. from your average whoop AIO VTX.

At 3g that’s almost 20% of my lightest whoop’s weight. You really don’t want that kind of weight even on 2s, and especially not on 1s. There are some ~1g DVR boards (and there are some VTX/DVR combos) but in my opinion they aren’t that much better than goggle DVR. They often lose entire recordings, skip frames etc.

Built in RX will be fine for 99% of things you will do with a 1s whoop. With 2s you might want to push extra range so yeah I’d go with external RX and 200mw + VTX in that case. I generally have terrible experience with anything built by HappyModel. BetaFPV is my favourite whoop part makes as their parts are fairly reliable (not perfect) and their customer support had been very helpful with providing replacement parts + free extras a few times when I had issues.

That’s a lot of text, sorry, I’m a bit passionate about micros :sweat_smile:

Oh and…

Motors aren’t an issue, you can always use higher KV than required with a throttle limit, but Mobula6 FC/ESC isn’t rated for 2s input so it wouldn’t work.

1 Like
5

Thanks so much for your advice! One more potentially dumb question, what is your opinion on putting 31mm props on the eachine trashcan to limit its power? Is that a completely ridiculous idea? I want the drone to be able to do some acro inside if that is even possible. I have being doing research on these drones for the past few days and it seems like my inexperience is showing lol. I was also planning on attaching a xt30 and upgrading the video antenna.

So for this quad I am looking to fly it inside a basement or some other medium to larger sized rooms. I am also hoping to fly it outside, but in the future I will probably build a tinywhoop!

6

Yes :slight_smile: better look into throttle limit. It takes a lot of skill to fly even the light 65mm whoops acro inside in tight spaces and any extra gram will make it so much harder, I think you’re getting ahead of yourself a bit.