Thanks to the folks over at Tested.com, through premium member build videos of a 3DR DIY Quad, I’ve a BIT become obsessed with building and flying my own multirotor. As I read through all the documentation at 3DR and at DIYDrones I became aware that the Pixhawk can be used to drive a variety of rotor configs. So, based on a few youtube videos and other places, I’ve spec’ed out the parts for a hexacopter including two options for motor+esc+prop and two options for Rx/Tx. I feel that, although this is my first ever build, I am technically and mechanically competent enough, i have an engineering degree after all, that I can put this thing together and fly it with the requisite patience. And since it is based on setups that have video proof of success I’m reasonably sure I’ve picked the right components. However, I would LOVE an experts eye on my build list. You can access it HERE. It should take you to google docs without any sign in required. This isnt my main copy so if if somehow you cause edits to the file dont worry about, but let me know so I can reverse it. Each part is hyperlinked to the item store page if you need to look at part details. If you think I totally missed something, can substitute something for something better, or you think you know where I can find a part cheaper please let me know. Also would love advice to keep in mind as I go as I build, test and configure various things. Thanks!
Well, you’re not going to need the hex power distribution board as it is all built in to the top deck of the frame. But then you knew that anyway from when you researched it, didn’t you.
I’m not sure why you feel the need for the esc programming tool, the esc should be pre-flashed and work out the box.
I have never bought specific bearing oil for my motors, just used a little light machine oil (very, very) occasionally.
I’ve heard of people having issues with the taranis, but that may just be down to the users, but personally for a newbie I would stick with something tried and trusted. You are already going to be on a learning curve with your flight controller and mission planner, you don’t need to be having to tinker with open source tx s/w.
I cannot see a 3dr power module or a separate bec for a 5v supply, but I’m not familiar with the pixhawk so perhaps you don’t need it. Unless you are thinking of getting it from an esc? Opto’s won’t give it to you and anyhow would not be my choice. Ah - wait, you were going to get it from the PDB? But you don’t need the PDB.
esc/motor/prop combo depends a bit on what you intend to do. Me - I run RC timer 740 kv/afro slim 20A esc/12" props. All good.
As for the other bits and bobs - I guarantee you will get so far through and find something missing!
All the above is just my 2cents worth and my own personal opinion. You or others may disagree.
Looks a lot like my build. I use the 680 when I’m mapping jobs that require that I fly. Luggage and battery restrictions rule out the Tarot 960 with it’s 22ah 6s batteries lol! The only difference I see is the motors, I’m using Sunnysky 4801 s 11 600kv motors. A few notes about the Pixhawk. You’ll want the 3DR power module to power the front end of your autopilot. Also as a backup and to supply power to the servo rails (IR triggers, servos and such can’t be powered from the servo rail), leave one power lead from one of the Afro esc’s or leave them all off and use a bec. Also, you’ll want a zener diode between the + and - on the servo rail. With this setup, if you power module fails, the power to the servo rain will back it up. If you google powering a Pixhawk you’ll find the documentation on the zener diode. The only other thing is the Afro speed controls. When used with the Pixhawk and larger pancake motors, you’ll run into really bad syncro problems. That translates to crash. Old firmware is the issue. Use you Afro programmer to install the latest firmware and you’ll be set. Do the sync test in mission planner before you fly though, just to make sure. Oh, almost forgot about the caps. With the esc’s at the motor locations I soldered in 3 220 low ESR capacitors to head off any problems. May not be necessary but a good idea and mandatory on longer leads light the 960 frame. This unit will map a good solid 20min with a Sony NEX 5n which is pretty good for the 13-4 tarot propellers (with two 5ah 4s packs). Good luck! Pixhawk rules!
[quote=“gdp2802”]Well, you’re not going to need the hex power distribution board as it is all built in to the top deck of the frame. But then you knew that anyway from when you researched it, didn’t you.
I cannot see a 3dr power module or a separate bec for a 5v supply, but I’m not familiar with the pixhawk so perhaps you don’t need it. Unless you are thinking of getting it from an esc? Opto’s won’t give it to you and anyhow would not be my choice. Ah - wait, you were going to get it from the PDB? But you don’t need the PDB.[/quote]
From the pictures on 3DR store for the Pixhawk, a power module comes with it i think. That provides primary power to the pixhawk. Going to email them and double check before ordering. Also, actually I was entirely aware of the built in PDB solder points on the tarot but was still considering using a separate pdb to let me swap things out without desoldering. I’ve since updated my own build sheet to get rid of the separate pdb as it means more fail points and unnecessary weight.
I was going to use an ESC to provide backup power as the Pixhawk is setup to take it from the ESC/servo ports. One thing I would need clarification on for the pixhawk is: when connecting the six ESCs do I clip all but one of the power leads? I was going to just plug them all in but after reading the powering the pixhawk guide it seems like this would overload the ports. Im still working out the motor/prop/esc/battery combo as I would like to leave lift capacity for a future addition of a gimbal+gopro. Initially I will be flying without any onboard video.
This is my updated and sorta final part list (aside from motor/prop if you guys can suggest a better combo): https://docs.google.com/spreadsheets/d/1phI6CG0FHv8FpT9I8WN_xSStTRg99nOR0xUyA5hsxM8/edit?usp=sharing
The power module is included with the Pixhawk. Clip all your esc’s wire except one for power to the rail. You won’t need it until you’re actually powering something like a gimbal, servos or a trigger. Don’t forget about the diode.