FPV quadcopters Build Log

As the technology behind FPV quadcopters Build becomes more advanced and less expensive, the number of enterprising hobbyists buying into the sport increases proportionately. Generally, the natural progression through the hobby involves a new pilot buying a ready-to-fly drone, flying and (often) crashing it, and then deciding to build one out of hand-picked parts. This can be a daunting task, especially for those without a background in electronics. With the right tools and the right information, though, building and flying an FPV quadcopter can be a rewarding and exciting experience.

Armattan-Chameleon-Main

Enter the Armattan Chameleon

When I was looking at parts for my first freestyle build in early 2018, one frame that kept appearing in my searches was the Armattan Chameleon. It looked really cool and innovative with its built-in camera cage, I appreciated the concept of a lifetime bumper-to-bumper warranty in a quad that was probably going to take some abuse, and it didn’t hurt that Joshua Bardwell lists the Armattan Chameleon as ‘The New Top Dog’ in his Freestyle Frames Shopping List.

The Armattan Chameleon has a sturdy, 4mm thick uni-body main plate with a motor spacing of 220 mm. Just by looking at it, you can tell it doesn’t sport the typical 8-standoff ‘FPV bus’ shape you see in other quads; instead its 2mm top plate is supported by a unique camera cage and rear standoff made of 4mm 6061 aluminum strong enough to withstand all but the most vicious crashes. Regardless, the whole frame is covered by an industry leading warranty program. Its 20mm deck-to-deck stack height also centers its mass (with a top-mounted battery) right on the prop line, which means rolls and flips will be much ‘snappier’ than a taller quadcopter.

As a word of caution, the Armattan Chameleon does not quite qualify as a ‘beginner’ build. The trade-off for a lower stack height is that you have less room to fit all of your components inside the frame. However, by pairing the frame with some Armattan Oomph Velvet motors, four individual Armattan BLHeli_S ESC’s, and a Betaflight F4 AIO FC, I had plenty of room and I have more than enough power to rip any park I can find.

Components

After deciding on the frame for your FPV quadcopter, you face the equally important task of choosing the electronic components to put on it. It’s crucial to select components that will be compatible with one another and to do your research to make sure they will function properly for your desired flying style. Since this was my first build, I chose to use Armattan motors and ESC’s with my Chameleon because they were a good stock option that would provide enough power for freestyle flying.

Wiring Diagram

It’s always a good idea to read and fully understand the documentation for your components before you start building a quadcopter. Luckily enough, FPVModel has a nicely illustrated wiring diagram on their Betaflight F4 product page. It shows how to wire both FrSky and DSM receivers, as well as a TBS Unify and a Runcam Swift 2, though you can adapt the wiring to any camera/VTx combination you choose. Use this diagram in build steps 1-4 below to correctly connect all of your components to the FC.

Betaflight F4 FC - Wiring Diagram

Components List

I chose these well-reviewed components for my Armattan Chameleon, and they have all been reliable as long as I have been flying it. You can choose any parts you like, but it’s always a good idea to research them first.

Armattan-Chameleon-Build-Pool

Build Process

Tools I Used:

  • Soldering iron
  • A medium-sized chisel tip
  • 63/37 solder, (63% Tin, 37% Lead)
  • 1.5 mm, 2.0 mm, and 2.5 mm hex-head drivers
  • Wire cutters
  • A hobby knife
  • Heat gun
  • Tweezers

Additional Materials:

  • Red and black 12 AWG wire
  • Male XT60 connector
  • Heat shrink, various sizes
  • Small zip ties
  • Double-sided mounting tape
  • Glossy general purpose spray paint
  • Paint pen
Armattan-Chameleon-Frame-1

Building the Frame

Parts: Armattan Chameleon frame and hardware kit, FPV camera

Tools: 1.5, 2.0, 2.5 mm hex drivers

Materials: Spray paint, paint pen

When building a new quadcopter, it’s best to assemble the frame before doing anything else so you have a way to dry mount your components and make measurements for later steps. I wanted to pursue a purple color scheme rather than use the original orange aluminum, so I put a couple coats of glossy spray paint on the aluminum pieces. I also used a purple paint pen on the edges of the main plate for some added flair.

Flight Controller Mounting

  • Thread 4x 12mm M3 cap head bolts through the bottom plate into the four FC mount holes into 4x M3 nylon nuts on the other side
  • Screw 4x M3 5mm soft mount bobbins onto the 12mm bolts
  • Screw 4x M3 nylon nuts onto four bobbins
Armattan-Chameleon-Frame-2
Armattan-Chameleon-Frame-3

Camera Cage Assembly

  • Thread a 10mm M3 bolt through each end of the HD cam adjustment bracket, through a carbon fiber plate, and through the main aluminum camera brace
  • Thread a third 10mm M3 bolt through the bottom hole in the carbon, into the main brace
  • Thread a 5mm M2 bolt through an M2 washer, through the rubber camera mount, and through an M2 sunknut
  • Push the rubber camera mount through the carbon so the main rubber part is on the same side as the main brace
  • Thread a 7mm M3 thumbscrew through the arc slot in the carbon, into the rubber mount
  • Repeat the above steps for the opposite side of the camera cage
  • Screw the FPV camera between the two 5mm M2 bolts (it will be harder to do this later when the cage is fully assembled)
    • You might need to use some bolts that come with your camera instead
    • At the same time, screw the bottom two M3 bolts into the 20mm M3 nylon standoff, securing it between the two sides of the camera cage
  • Seat the HD cam carbon plate on top of the aluminum HD cam braces and screw in 8x 5mm M2 cup head bolts
  • Slide the slots in the cage onto the front of the main plate and line up the 4 screw holes
  • Attach the cage to the frame using 4x 12mm M2 cup head bolts.

Top Plate Attachment

  • Install the rear standoff using 2x 8mm M3 cup head bolts
  • Attach the top plate using 2x 8mm countersunk M3 bolts in the rear and 4x 5mm M2 cup head bolts in the front
Armattan-Chameleon-Frame-4

Connecting Motors, ESC’s, and FC

Parts: 4x Oomph Velvet, 4x 30A ESC, 4x motor soft mount, Betaflight FC, buzzer

Tools: 2.5mm hex driver, wire cutters, soldering iron

Materials: ESC heat shrink, mounting tape, 12AWG wire, male XT60 connector

Motor Installation

  • For a standard ‘props in’ motor configuration, arrange your motors as follows:
    • M1, M4 = CW
    • M2, M3 = CCW
  • Line up 4x silicone soft mount pads over all 4 screw holes for each motor
  • Use the included 16x 8mm M3 screws to attach all 4 motors
Motor-Order
Armattan-Chameleon-Motors
Armattan-Chameleon-Motors-2
  • Measure out where you would like each ESC to sit on the arms and stick them temporarily to the frame with the mounting tape
  • Measure and cut all motor wires to reach the ESC’s
    • Always follow the old handyman’s rule: measure twice, cut once!
  • Seat the FC on top of the soft mount bobbins installed in the main plate
  • Measure and cut the ESC power, ground, signal, and ground wires so that they reach the FC
  • I had to flip the FC over to solder ESC power and ground to the ESC’s – it helps to follow the ‘Flip-Over’ technique from Drone Build Tips and Tricks – Part One
  • For motor 1:
    • Solder 3 motor wires in order to 3 ESC pads
    • Put heat shrink over the ESC before soldering to FC
    • ESC power to ‘M1+’
    • ESC ground to ‘M1-’
    • Signal to ‘M1’
    • Signal ground to ‘Gnd’
    • Repeat for motors 2, 3, and 4
  • Shrink ESC heat shrink, but wait to secure ESC’s to frame
  • Using a hot iron and lots of solder on the 12AWG wire:
    • Solder black to ‘GND’ (on FC top)
    • Solder red to ‘+’ (on FC bottom)
    • Solder the other ends to the male XT60 connector, taking care to use the correct polarity
  • Buzzer installation:
    • Red wire to ‘BZ+’
    • Black wire to ‘BZ-’
Armattan-Chameleon-ESC 1
Armattan-Chameleon-ESC 2

FPV System and Receiver

Parts: FPV camera, Video Transmitter, FPV antenna, R-XSR Receiver

Tools: Soldering iron, wire cutters

Materials: Zip ties, mounting tape, heat shrink

If I were to redo this build, I would have soldered the camera, VTx, and receiver wires to the underside of the FC instead of the top. This would keep them from interfering with a battery strap encircling the top plate. Either way I found it helpful to put some heat shrink around groups of wires to keep them together.

Camera Wiring:

  • Cam ‘ 5-36V’ to FC ‘CAM’
    • Solder bridge ‘CAM’ with ‘VBAT’
  • Cam ‘GND’ to FC ‘AGND’
  • Cam ‘VIDEO’ to FC ‘VIN’

Video Transmitter Wiring:

  • VTx ‘VBAT’ to FC ‘+’
  • VTx ‘GND’ to FC ‘AGND’
    • This creates a shared ground loop between camera and VTx, which reduces video noise
  • VTx ‘VOUT’ to FC ‘VOUT’
  • VTx ‘Smart Audio’ to FC ‘TX3’

Receiver Wiring:

  • Rx ‘GND’ to FC ‘GND’
  • Rx ‘5V’ to FC ‘5V’
  • Rx ‘S.Port’ to FC ‘TX1’
  • Rx ‘SBUS’ to FC ‘SBUS’

SmartPort Telemetry takes a little hand-waving to get it to work; it involves soldering the S.Port wire to a small uninverted signal pad on the R-XSR. For more information, check out this article on

Uninverted SBUS from FrSKY Receivers.

Armattan-Chameleon-VTX-1
Armattan-Chameleon-VTX-2

Finishing Touches

Parts: Capacitor, Stikitskin, AXII Stubby

Tools: Soldering iron, wire cutters

Materials: Zip ties, mounting tape

  • Using a hot iron and some more solder, solder the capacitor to the battery leads, paying close attention to use the correct polarity
  • Peel the Stikitskin from its template and stick it to the bottom of the frame, taking care to line up all the edges with the arms
  • If you want to use Armattan’s Rx antenna tubes, mount them under the frame using the Rx antenna holder. Then thread both Rx antennas through the tubes. Add heat shrink if desired, and heat tubes to bend them to shape.
  • Secure all four ESC’s to the frame with mounting tape and zip ties
  • Plug in the FPV camera wire harness
  • Plug the VTx wire harness in and mount the VTx under FC with mounting tape and a zip tie
  • Connect in the VTx pigtail, insert the SMA mount into the rear standoff, and tighten the locknut on the opposite side of the standoff
  • Screw the AXII stubby antenna onto the SMA pigtail
  • Plug in the Rx wire harness and mount it on the frame with mounting tape and a zip tie
  • Follow the binding procedure included with your receiver
Armattan-Chameleon-Wrap-Up

Betaflight Configuration

Resources: Betaflight ConfiguratorBLHeli Configurator Chrome AppImpulseRC Driver FixerZadig

Below are the settings I used to configure my Armattan Chameleon in Betaflight. When in doubt, I refer to Joshua Bardwell’s video on Betaflight 3.4 & 3.5 Setup For Total Beginners where he talks about flashing, drivers, and troubleshooting.

Flashing firmware:

  • Open Betaflight and connect the FC to your computer via USB
  • In the CLI tab, type ‘bl’. The FC should now be in bootloader mode
  • Return to the Betaflight Firmware Flasher and choose the BETAFLIGHTF4 target
  • Download the firmware and flash. Keep the FC plugged in until it shows that it flashed.

Ports Tab:

  • UART2 Telemetry Output = SmartPort
  • UART3 Peripherals = TBS SmartAudio
  • UART6 Serial Rx = On
  • Save

Configuration Tab:

  • ESC/Motor protocol = DSHOT600
  • Receiver mode = Serial Based Receiver
  • Serial Receiver Provider = SBUS
  • Telemetry = On
  • Airmode = On
  • OSD = On
  • Anti Gravity = On
  • Dynamic Filter = On
  • Save and Reboot

Receiver Tab:

  • Set the Channel Map so the correct channels respond to inputs (default for FrSky is TAER1234)
  • To enable RSSI in your OSD, follow this guide: FrSky RSSI Configuration for Betaflight/Butterflight
  • Save
  • Create three AUX channels on your transmitter to use for arming, flight mode, and beeper

Modes Tab:

  • Assign each AUX channel to a function. I used:
    • ‘ARM’ on AUX1
    • ‘ANGLE’/’HORIZON’ on AUX2
    • ‘BEEPER’/’FLIP OVER AFTER CRASH’ on AUX3
  • Set the range of each mode, taking care with the positions of any 3-position switches
  • Save

OSD Tab

  • RSSI Value = On
  • Main Batt Voltage = On
  • Timer 2 = On
  • Fly Mode = On
  • Current Draw = On
  • Mah Drawn = On
  • Warnings = On
  • Avg Cell Voltage = On
  • Organize OSD elements as desired
  • Save

BLHeli Configurator:

Armattan-Chameleon-Complete

Build, Fly, Crash, Repeat

Completing an FPV quadcopter build like the Armattan Chameleon catapults a new pilot into an entirely different side to the hobby. You now intimately understand the inner workings of your drone, and if you break any component on it, you can simply disassemble it and fix it. In this guide we covered some field-tested parts you can use to fill out a Armattan Chameleon build, the entire build process, and the configuration steps to get your quad in the air.

The Armattan Chameleon is definitely a popular choice for a freestyle build, but that only validates the development that Armattan put into it. Making a tank of a frame this fun to fly and backing it with a lifetime bumper-to-bumper warranty is a formula for great success. This build will take a beating and keep on asking for more. So get flying!

Mepsking FPV Forum, where you can learn everything about drone and flying skills. check mepsking store if you want to buy drone parts.

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