Quadcopter Parts List
I was asked recently what would be a good way to start in multirotors. The first question was "A tri-copter must be simpler and easier because there's only 3 motors?". I disagree. I've built quite a few tricopters and on each one explored a different way of building the yaw control mechanism on the tail motor. Some worked well, some not so well but by the time the servo is mounted and linkages hooked up, it all gets more complicated and less reliable compared bunging on a fourth motor and prop spinning in the opposite direction. I think what finally converted me was assembling the DJI F450 frame with the Naza controller. This quad was smooth and stable from the first flight and is an ideal platform for mounting a GoPro camera on for some aerial photos & videos. The downside of the DJI is that it's not cheap. I spent over $600 on the Flight controller, frame kit and GPS module and that's assuming you already have LiPo batteries, LiPo charger, radio control transmitter & receiver and other bits and pieces. It can quickly become an expensive option especially if you're just getting started.
Another option is the "toy quads" you'll find in electronics stores or maybe even the local shopping centre. They're cheap and maybe a good way to get a taste for flying multi-rotor but they have certain disadvantages;
1) The parts are generally not re-usable for your next project. The motors, ESCs and controller are so deeply integrated they're not easily adapted to another frame.
2) Often they're quite small with payload capacity to match. The small quads will struggle to carry much more than a lightweight spycam let alone a GoPro or pocket digital camera.
So what to buy for a simple, cheap, respectable quadcopter with parts that could be re-used in your next project, maybe a hexcopter. This shopping list should cover absolutely everything you'd need to start from scratch.
Flight Controller: $29.99 Hobbyking KK2.0 Multi-rotor LCD Flight Control Board
Auto-level with and LCD screen for configuring and tuning. Eight outputs good for tri-copter up to Octo-copter. The downside is no barometric pressure sensor (height hold) or GPS (position hold) but at that price, those features aren't expected. It also has a built in voltage monitor that outputs an audible alarm at a programmable low voltage level. This feature requires a couple of extra wires soldered to the board and is well worth the trouble.
Frame: $17.99, Q450 Glass Fiber Quadcopter Frame 450mm - Integrated PCB Version
A simple, sturdy frame that comes with an allen key for the 2.5 and 3mm boltsand even a velcro strap for the battery. The lower board has an integrated PCB which means there's no need a messy power distribution cable arrangement.
Motors: $14.99 (x4), NTM Prop Drive Series 28-26A 1200kv / 250w
Ideal size and power for this frame. The mouting holes align perfectly. Something odd with this motor I hadn't come across before was the shaft sticking out the rear / bottom of the motor. The accessories pack is needed as a propeller mount and uses three bolts to attach to the motor. I quite like this method as compared to the prop savers with the rubber o-ring or the collet style adaptors.
$1.89 (x4), NTM Prop Drive 28 Series Accessory Pack
You won't need the motor mount or the four silver screws, just the prop adaptor. With the Q450 frame, the bolts go through the frame and straight into the bottom of the motor.
$12.19 (x4), TURNIGY Plush 30amp Speed Controller
Simple, reliable, does what it's supposed to without any fuss. The difference in weight between the 18, 25 and 30 Amp ESCs is barely worth compromising the current capacity for.
$1.59, PolyMax 3.5mm Gold Connectors 10 PAIRS (20PC)
Some might solder their motor wires straight to the ESC but I've never been organised enough to plan that far ahead. I need the flexibility to swap any two of the three motor wires. I've read alot about bad or loose connections that have caused crashes. I've never experienced this type of failure. I think probably because it all comes down to a good solder joint.
$2.46, Slow Fly Electric Prop 8045R (4 pc - Green, RH Rotation)
Eight inch, Right Hand (RH / Clockwise) rotation. Four to a pack but you'll only need two with two spares. At these prices though, if you're ordering any spares, props should be high on the list. Get two packs.
$2.29, Slow Fly Electric Prop 8045 SF (4 pc - Green)
As above but they turn the other way. I like coloured props (as opposed to black) because they're much easier to see. In bright daylight, black props look almost invisible compared to green props which seem to present a good contrast against the sky.
$4.75, 10CM Male to Male Servo Lead (JR) 26AWG (10pcs/set)
These connect the receiver to the inputs on the flight controller board.
$16.38, Turnigy 2200mAh 4S1P 20C Lipo Pack
Minimum capacity and C rating you'd want to use for a decent flight time.
Now up until this point, it's assumed you already have some RC equipment from other projects. For those that are starting out and need a LiPo charger and Transmitter / Receiver etc, here are some suggestions.
$53.95, Turnigy 9X 9Ch Transmitter w/ Module & 8ch Receiver (Mode 1) (v2 Firmware)
From accounts I've read online, the Turnigy radios are a good way to get started. A nine channel radio and receiver for just over $50 is good value! This package doesn't come with batteries or charger but seeing as most people will already have these, it makes sense for Hobbyking to exclude these parts.
$6.89, HobbyKing 1500mAH LiFe 3S 9.9v Transmitter pack.
A Tx is no good without power. Compatible with the charger below but you'll need another lead for charging.
$16.99, HobbyKing 50watt 5A X-Charger/Balancer
This battery charger will be enough to get you up and running doing balanced charges on LiPo's. It will also charge NiMH and NiCd batteries often used in transmitters. Note - it is a DC only input so you'll have to hook it up to a car battery or similar and can't plug it onto 110 / 240 AC wall outlets. For a charger with both DC & AC input, look at a "B6-AC Plus - Charger/Discharger 1-6 Cells Dual Power (COPY)" or better.
$2.69, Charging harness
Use this harness to charge the Tx LiFe battery. You'll probably never use ALL the connectors on this charging harness but even if it means cutting some off and re-purposing with a different connector, for a few dollars it takes the pain out of soldering up wires to banana leads.
I think that's pretty much everything you'd need to get in the air with a decent quad. The best thing about this setup is that down the track you could directly swap the KK2.0 control board for maybe a DJI Naza controller and add altitude and position hold, without having to change any motors or ESCs. The parts are all fairly cheap to replace so those first few crashes shouldn't be too painful on the wallet. If you can afford to, get two frames (1 for spare) so you don't have to wait weeks for another delivery from Hong Kong to repair / replace parts. Spare propellers are a must have and considering the price of them, it's a no brainer to order a few more packs of them.
There are a few more items like spare battery packs and LED strip lighting that you'll probably want to add down the track but for now the objective is to get a quad in the air for cheap, but not too cheap to make it nasty.
Ok so to recap, here's the parts list summary and totals;
Flight Controller: $29.99 Hobbyking KK2.0 Multi-rotor LCD Flight Control Board
Frame: $17.99, Q450 Glass Fiber Quadcopter Frame 450mm - Integrated PCB Version
Motors: $14.99 (x4), NTM Prop Drive Series 28-26A 1200kv / 250w
$1.89 (x4), NTM Prop Drive 28 Series Accessory Pack
$12.19 (x4), TURNIGY Plush 30amp Speed Controller
$1.59, PolyMax 3.5mm Gold Connectors 10 PAIRS (20PC)
$2.46, Slow Fly Electric Prop 8045R (4 pc - Green, RH Rotation)
$2.29, Slow Fly Electric Prop 8045 SF (4 pc - Green)
$4.75, 10CM Male to Male Servo Lead (JR) 26AWG (10pcs/set)
$16.38, Turnigy 2200mAh 4S1P 20C Lipo Pack
$53.95, Turnigy 9X 9Ch Transmitter w/ Module & 8ch Receiver (Mode 1) (v2 Firmware)
$6.89, HobbyKing 1500mAH LiFe 3S 9.9v Transmitter pack.
$16.99, HobbyKing 50watt 5A X-Charger/Balancer
$2.69, Charging harness
A grand total of $272.25. A bit pricier than I was aiming to get it but don't forget that theres about $80 worth of radio and charging gear that can be re-used in the next multirotor. Once you've built one, you won't stop at that. Tri, quad, hex, octo ... they're all possible with these same parts.
****If I've forgotten anything on the list, leave me a comment below 🙂
DJI Naza F450 Gain Settings – Flips and rolls
The settings I've been using up until this point were;
Basic Gain: Pitch: 150, Roll 150, Yaw 100, Vertical 120
Attitude Gain: Pitch 70, Roll 70
The problem I found with these settings was under heavy acceleration, the quad would oscillate. The same oscillation would occur with high yaw application and when descending from height. After some forum reading I decided to enable "Remote Adjust" by assigning X1 to the Basic Gains and X2 to the Attitude Gains. The oscillation on descent was apparently due to too low gain on Attitude settings.
By using "Remote Adjust", the gain settings can be changed in-flight and the affects judged immediately. I found increasing the Basic Gains to max the quad would start oscillating even just in a hover. Backing it off a few notches would stabilise the quad and give quite good response to input. Dialling the gains all the way down meant the response was much softer and smoother which meant response to input is slowed somewhat. Without knowing what the actual values were at the time, I settled on gains that seem to be a good mix between control authority and smooth flight. There was still some vibration but I'll work on that.
I think I'll keep the Remote Adjust capability setup on the Quad. Being able to dial back the gain for some slow smooth input for photos and video and then dial it up for some hot-dogging is a great feature. All without having to stop and plug in the laptop.
The gain settings I settled on are;
Basic Gain: Pitch: 104, Roll 104, Yaw 69, Vertical 83
Attitude Gain: Pitch 150, Roll 150
Spider quad build
The motors, ESCs, and control board (FelyuTech FY-91Q) board are all mounted. Now I just need to connect them all.
Just mucking around with this control board while waiting for the DJI Naza to arrive.
Tuning for auto-level – MWC Quad
According to the instructions on multiwiicopter.com the mid and endpoints need to be set properly to ensure auto-level works properly. I hadn't bothered much with this except to make sure the throttle travel was low enough to arm the PARIS board. This is probably why I've spent so much time stuffing around with trimming flights trying to get the perfect autolevel hover. After so many trimming flights, I thought it would be good to go back to basics and start from the ground up. Especially since I've just finished assembly of the new Scarab Quadcopter, now is a good time to get things right.
Setting the low point to 1095, the midpoint to 1500 and the high point to 1905 is achieved via sub trim and end point adjustment (on my Futaba 10CAP). The first step is to get the midpoint right at 1500. For this example, I'll assume a working connection between your PC running Multiwiiconf software and the Paris board.
- Center all the transmitter sticks and trims.
- Read the values from the MWC software. They should be close to 1500.
- On the Futaba 10CAP, hold down MODE, then Sub Trim and adjust all 4 channels to as close as possible to 1500.
- Then use the END POINT function on all four channels to high and low point to 1905 and 1095 respectively. Using the elevator as an example, pull full back on the elevator stick and read the value in the MWC software. Hold the stick there while adjusting END POINT so the readout shows 1095. The push the elevator stick on the tx to the other extreme and use END POINT to adjust the readout in MWC to 1905.
- Repeat the process for the other three channels.
- Go fly and see what happens. In my case I'm getting a bit too much oscillation when I activate auto-level that I'm sure can be solved with some PID tuning. I also seem to get the occasional glitch where it seems two motors drop RPM just enough to cause a small drop in altitude. I'm not sure if it's actually a drop in RPM or vibration as I reckon I can perceive a slight amount of vibration. Come to think of it, those two booms are the ones missing one of the four screws in the boom holder because the shafts thread was stripped or non-existent. I do have two spares that came with the kit so it looks like I'll have to go back, disassemble and replace those shafts.
MWC Quadcopter – Cramming in the ESCs
These photos show the frame starting to come together. The bottom of the CF plate shows each of the four ESCs are held in place by 2mm cable ties. There's not a lot of room left on the top of the board after the ESCs and power distribution cable is laid down. On top of this will come the three leads from each motor to plug into the ESC. If you were thinking of using any gauge wire heavier than 20AWG, you might want to think again because even just space will become an issue.
The next plate above is prepared with nylon mounts to host both the MWC control board and above that will be another quad frame plate that is likely to host my GoPro camera. I haven't decided yet whether to put the camera up on the top plate or out in front on an extended arm. Up top under a dome would be better balanced and protected, but out on the arm might have a better view clear of the props. Undoubtedly I'll end up trying both but seeing as I don't have the extended arm, and it costs more money, I'll see how it goes up top first.
QuadCopter SCARAB – Motor Mount Retainer
These photos show the retaining screw cut to 7mm and how it penetrates one quadrant of the 12mm aluminium tube divided up by the motor mount. Cut to the right length, it doesn't intrude far enough to cause concern with rubbing on the wire from the ESC to the motor which is routed internally along the tube.
QuadCopter SCARAB 12 – Assembly part 2
The frame looks well laid out, light weight and just plain good looking. 20AWG is used to connect to the 2213N 800Kv Brushless Motors with just enough left hanging out the end to connect the four speed controllers ( TURNIGY Plush 12amp (2A BEC) BESC ). The only thing I'm unsure about so far is the sorta sharp edges of the aluminium booms and how that might rub against the wires.
Canola from the air
It seems every second field is full of Canola around Shepparton at the moment. Here's a few quick ones I took on the way to the Mammoth Scale Fly In at the Valley Radio Flyers.
I did lose the quad once, quite deep in the canola field and thought I could be searching for quite a while but I took the transmitter with me while searching and gave the throttle a little blip every now and again and found it fairly easily.
Connecting the BMP085 Baro to the MultiWiicopter Paris V4
The BMP085 Barometric Pressure sensor is mounted on the bottom side of the Paris V4 board. Orientation of the BMP085 is not important but vibration is always an enemy so I used double sided foam tape to mount it. There are four points from the BMP085 that must be connected, VCC, GND, SDA and SCL. In this case they're connected to the LV I2C pads on the bottom side of board to the same points that the BMA180 Acceleromter is connected to on the top
Yellow wire is SCL. White wire is SDA. Red VCC and Black GND.
Photos of flashing the HobbyKing Quadcontroller
Just a couple of photos showing a 3S 2200 powering a BEC powering the Hobbyking Quadcontroller board connected to a USBasp Atmel Programmer connected to a Windows XP machine running the KK Multicopter Flash tool.
