Quad Zero Kit - Assembly Guide

The Quad Zero Kit is a lightweight (<250g) platform with a 3D-printable frame, agile flying envelope with extended flight times yet simple to setup. It is powered by our most popular flight controller yet, the Control Zero H7 OEM on top of custom made motors and a carrier board that includes power monitoring, integrated ESC module, Time-of-Flight sensor for precision landing (Z-axis), and additional ports to support any OSD, GPS, CAN, telemetry and any other payload peripherals.

This kit is perfect as a development platform, educational, or even a light show drone – light and FPV pod coming soon!

We put together this guide to help you get up and running with your QZKit platform as fast as possible. Please note that this build may take anywhere from 3 hrs to several sessions depending on your particular experience.

What's Included

Please make sure you have all the parts listed below, if something is missing or you have any questions please do not hesitate to contact us. Spare or extra parts are available individually following the links.

If you ordered the optional Dual-Band WiFi Telemetry Radio:

Required tools

• M1.5 hex driver

• M2 hex driver

• Hobby knife

• CA glue

• Accelerator - optional

• Soldering iron

• Solder wire

• Double-sided tape - 3M VHB recommended

• Prop balancer - optional

• Scissors - optional

Extra resources

• ExpressLRS compatible transmitter

• Ground station - any laptop, tablet or embedded device running Mission Planner or QGC

Step 1 - Attach motors to the frame

Allocate the following materials:

• 12x M1.6x4mm screws (included inside the motors)
• 4x M2-2202 brushless motors
• Quad Zero frame

Take one M2-2202 brushless motor from its box and make sure the rotor can spin freely. Screw it in place with 3x M1.6x4mm hex screws with your M1.5 hex driver.

NOTE: Make sure the motor's wires point down the frame's arm. See figure below.

Repeat the above steps for the remaining 3 arms. Due to the nature of the manufacturing process, your frame may have elephant foot artifacts; if this is the case please remove it using a hobby knife to ease motor placement.

Once you finish placing and screwing all the motors your frame should now look something like the picture below.

Step 2 - Carrier board subassembly

Carrier board prep

Connect ESC signal cable

Grab the colorful JST-SH 6 to JST-SH 6 cable and plug it as in the image above.

This cable is generally installed during testing, so this step may not be necessary.

Remove ToF sensor protective cover

Carefully remove the yellow tape with the plastic tweezers or with your fingers.

Vibration dampers

Cut the provided vibration dampening material by half so you end up with 4 small pieces, to do so you may use a hobby knife or scissors.

Remove the plastic cover on one square and place a small drop of CA glue in the center of any square on the carrier board's back side. Press the square firmly for 10 seconds or until the square no longer slides on the surface.

Repeat for the rest of the corners.

Secure in place

Place the carrier board on its back and remove the remaining damping material adhesive cover.

Add a CA drop on top of each dampening square.

Mount the carrier board onto the frame using the tabs and the side holes to align the carrier assembly. You won't see the tabs in the GIF below, but we changed the steps order so the alignment is easier.

Press firmly for 30 seconds or until CA has tacked.

Remove break away tabs

To remove the tabs you may use any tweezers or bare fingers. Apply a torque or twisting force carefully along the axis of the dotted line, otherwise you may damage the internal layer stackup of the board.

Step 3 - Soldering

Battery connector

Solder the BT2.0 pigtail onto the battery terminals of the M10112 carrier board. The red wire should match the '+' sign in the board.

Motors

Cut the motor cable in order to reach the carrier board's motor pads, our small trick to get the wire length correct consists in pulling the wires above the carrier and cut arpund 5-6mm from the edge of the board. Then strip 3-4mm and pre-tin the ends.

Don't worry for the motor directions at this point, we will verify that using software at a later time. However if you pay attention to detail, you may skip a step later if you solder the front right [A] and rear left [C] motor wires straight (as-is) and swapping any two out of the three wires for the front left [D] and rear right [B] motors. Note: Letters in brackets refer to the corresponding motor as labeled in the carrier board pads.

Motor cable management

This is a recommended step which may be completed with a couple of techniques. In previous versions of this guide we recommended using SuperX glue, however the CA method is faster and cheaper. However using a zip tie, hot glue or similar materials is enough. The goal is to mitigate the vibrations from the cables freely moving under the prop wash and prevent prop strikes.

Once you have all the motors soldered, gently pull the cables from the motor towards the center of the frame and apply a generous drop of CA glue at two thirds of the arm's length, making sure it covers the cables. Then apply CA accelerator and wait for it to tack.

Check the following pictures for details.

Step 4 - RF subassembly

You may put the frame assembly on the side for the next couple of steps.

DualBand Telemetry radio

We will start this section by opening the bag that contains the Dual Band telemetry radio. Please handle with care and take ESD protection measures, be particularly rigurous on this if you live in a very dry area.

Allocate the GPS Riser and grab the two 2-56x⅛" nylon hex screws to attach the M10114 Dual Band telemetry radio board to the plastic riser as pictured below.

If you are not using the Wifi telemetry radio, you may place any other type of telemetry radio, always taking into account the interference this may cause to the GPS receiver.

Connect each of the DualBand telemetry radio antenna cables to a u.Fl connector on the wifi module.

Now place the EMI shielding on top of the WiFi telemtry radio, making sure to completely cover it.

GPS Receiver

Place a small 9x9mm double sided tape square and place the GPS on top. We recommend to put smaller squares to increase the contact area, however we have found that the small square is enough.

Install autopilot board in place

Remove the Control Zero H7 OEM autopilot from its anti-static packaging taking the same precautions as in the previous step.

Place it with the arrow pointing to the left side of the carrier board, the ToF sensor protrusion is the front direction. There is only one way to couple the FC board to the carrier, since the front header has 36 pins and the rear header has 40 pins.

If for any reason you need to remove the Control Zero board, you may do so with the included plastic tweezers, using them as a lever to gently separate each connector 1-2mm at a time.

Secure RF subassembly to frame

Gently bend the antenna cables 180 degrees so you are able to place it on the right side of the frame. We suggest securing the GPS riser in place before glueing the antenna. To do so, use 4x 2-56x3/16" nylon hex screws.

See picture below for reference. Use CA glue to strengthen the bond as needed.

Cable management

Take one MRC-0292 JST-SH 6-pin to JST-SH 6-pin cable and connect it to the SERIAL labeled connector of the M10114 board (telemetry), then connect it to the TELEM2 port of M10112 carrier board. Check the previous picture for reference.

You may push the extra cable between both boards, making sure not to bend them aggressively.

Then take one MRC-0243 JST-SH 6-pin to JST-GH 6-pin cable, connect the GH end to the GPS Receiver board and rout it through TELEM2 and between GPS and telemetry radio cable, then pull connector from the left side to connect it in the GPS labeled connector on the carrier.

Radio RX wire prep & placement

NOTE: We cannot guarantee the firmware version that ExpressLRS or our distributors ship the receivers with. We recognize this situation might not be ideal for ease of use and are actively working on solutions.

We decided to go with the ExpressLRS receivers due to their compact size and performance. Depending on your specific needs, you might choose to place the receiver in various locations on your drone. This guide will focus on a common setup where the receiver is mounted on the side of the frame.

For starters, once you have the ExpressLRS receiver, take the receiver and the 6-pin JST-SH cable and identify the required connections you'll need. Use the pinout diagram of the ELRS receiver below to properly identify power (5V), ground (GND), and signal (TX and RX for telemetry).

Trim the JST-SH 6 cable to about 70mm or about 2.76 inches. If you require to place your receiver elsewhere feel free to do so and cut the cable to your desired length.

Now remove the CTS and RTS cables from the JST housing since ELRS receivers do not support hardware flow control.

Then strip 1mm of silicone-coating from the ends of the 4 cables that you trimmed, and pre-tin them to make the soldering process much easier.

Next follow the telemetry port pinout chart provided below while soldering the pigtails to the ExpressLRS receiver pads.

After you finish soldering the JST cables to the ELRS receiver pads, cut a piece of double sided tape and put it on the side of the board opposite to the ceramic antenna side.

ExpressLRS Configuration:

Download and install ExpressLRS Configurator. The configurator is used to compile and flash firmware to the ExpressLRS module and the ExpressLRS receiver. Click here to follow the steps to download and install the configurator.

Download the latest ExpressLRS Configurator, looks like the current version is 1.6.1 and find the version that also matches your operating system.

This guide will be using the Radiomaster Zorro with Internal ExpressLRS TX to bind to the ExpressLRS receiver. But you can use any radio with an internal or external ExpressLRS transmitter.

To bind the radio to the receiver, we first need to flash our module and get the ExpressLRS Lua Script onto our radio.

A Lua Script is a program that runs on the radio and is used to configure the ExpressLRS system

Radios with ExpressLRS built in come pre-shipped with the ExpressLRS Lua Script installed, but if you want to check to see if you have the latest version in your radio press the SYS key, then go to SD Card, scroll down to [SCRIPTS], then scroll down to [TOOLS], click on it and you should see elrsV3.lua as one of the options. (Keep in mind that elrsV3.lua is the latest version when creating this guide)

If you have an older version of Lua Script, you’ll need the latest version, so connect your radio via usb to your computer. Once you connect your radio, a menu will pop up on your screen. Click on USB Storage (SD) option.

Once your radio is connected, go to the ExpressLRS Configurator that you downloaded earlier.

We're going to choose the version of firmware that we'll need to flash, and we'll pick the latest released version.

Scroll down to Target, click on Device Category, and select your transmitter module type. Then, under Device, choose the specific transmitter module.

Now select the WIFI option under Flashing Method and click on the blue box to download the Lua Script.

Save the new file.

With the downloaded file, navigate to the Untitled drive. Look for the SD Card contents within the drive, go to SCRIPTS -> TOOLS and save the elrsV3.lua file in the TOOLS folder.

After transferring the downloaded Lua Script file to your radio's SD Card, unplug your radio to configure its settings.

Press the MDL key on your radio and navigate to the MODEL setup menu. For an internal ExpressLRS module, set the internal module to CRSF. For an external module, turn the internal RF off and set the external RF to CRSF.

Next thing we need to do is exit MODEL settings, press SYS, and navigate to the TOOLS page. Click on ExpressLRS and adjust the ExpressLRS Lua Script settings as follows:

• Set Packet Rate to 500Hz.

• Change Teleme Ratio to Std (1:128).

• Switch Mode to Wide.

All other settings can be configured according to your preference.

Back in the ExpressLRS Configurator, select your regulatory domain according to your location: - For the EU: Choose REGULATORY_DOMAIN_EU_CE_2400 - For any other location: Select REGULATORY_DOMAIN_ISM_2400

Under Device options make sure the Standard mode is selected.

Leave the Extra data option as is. Under Network, click on AUTO_WIFI_ON_INTERVAL, and set the Value to 60 if it isn’t already.

Navigate to Binding phrase setup and click on BINDING_PHRASE, then enter your phrase in the Custom binding phrase box that appears.

Select UART_INVERTED under Compatibility options.

After all the parameters are set in the ExpressLRS Configurator, click Build at the bottom of the configurator. If it’s your first time, the loading process might take up to 10 minutes.

After the Build process completes, you'll receive a file necessary for flashing your module via WiFi. Save it in an easily accessible location.

Return to your radio, press the SYS key and run the ExpressLRS Lua Script once more. Scroll down to Wi-Fi Connectivity and select Enable Wi-Fi.

While the Wi-Fi is running, look for ExpressLRS TX in the visible networks on your computer. - The network password is: expresslrs

After connecting to the ExpressLRS TX wi-fi network, open up your browser and type the ip address 10.0.0.1

The ExpressLRS update page will pop up, and you'll need to scroll down to find Firmware Update. Click on Choose File, select the .bin file created during the Build process, and then click Update.

Now that you have completed updating the radio's firmware, it's time to update and bind the receiver. Go back into the ExpressLRS Configurator and keep the same settings that you set prior for your transmitter except for the Target options. - In Device Category select GEPRC 2.4 GHz. - In Device select GEPRC Nano(SE) 2.4GHz RX

Next, scroll down to the bottom of the page and select Build. Once the Build process completes, you'll receive a firmware.bin file necessary for flashing your ExpressLRS receiver via Wi-Fi. Save it in an easily accessible location.

Now power up your quadcopter; the receiver's blue LEDs should start blinking. Wait for 20-30 seconds until the LEDs blink rapidly, showing that it's in Wi-Fi mode.

Then, do the same process you did with the radio, find and connect to the ExpressLRS RX Wi-Fi network on your device and connect using the password: expresslrs

Just like you did with the transmitter, type the ip address 10.0.0.1 into your browser. select Choose File under Firmware Update: and select the firmware.bin file. Then click Update to flash your receiver.

Finally, connect your quadcopter to Mission Planner to set up the needed parameters so that the Expresslrs receiver works properly.

In Mission Planner go to CONFIG ---> Full Parameter List. Set these parameters:

Mission Planner Parameters:

Then select Write Params

Go back to DATA select Actions select Preflight_Reboot_Shutdown then select Do Action

Step 5 - Autopilot Configuration

You will have to evaluate which flight stack you will be running in your QZKit. The mRo Control Zero H7 OEM is supported by Ardupilot and PX4, both broadly capable and stable open source projects. We provide instructions for both platforms with a minimum set of directions and parameter files.

Ardupilot

The mRo Control Zero H7 OEM board comes with Ardupilot flashed out of the box. Connect your carrier board to any computer running Mission Planner software and update to the latest stable version, AC4.3.3 at the time of writing. Please follow this guide if you need further details.

Parameter list

After updating the firmware, connect via MAVLink using 115200 as baud rate value, this setting is located on the top right corner of any screen in MP software, then click on the Settings tab.

Click the Load Parameters button and select the downloaded .param file. Click to download

Allow once you press OK button (reboot prompt) wait until the beep Parameters succesfully saved Should reconnect auto, if not just press disconnect and Connect .

PX4

Even if our board ship with Ardupilot out of the box it doesn't mean using PX4 is an advanced or complicated task. Fortunately both projects offer a common bootloader behavior which will be recognized by either software. Please do not attempt to change the bootloader. The steps to load PX4 onto the Control Zero OEM H7 board are the following:

1. Open QGroundControl software. Leave the carrier board unconnected.

2. Click on the upper left corner (QGC logo), then click the Vehicle Setup button.

3. You should see that there are only two tabs on the left pane: Summary and Firmware. No hardware should be connected at this point!

4. Click on the Firmware button and proceed to connect your board.

5. Select the branch or firmware flavor you need to upload. Note that you can choose either PX4 Pro or Ardupilot software from the menu. If you check the Advanced settings box you may select to upload any other binary. In this case select PX4 Pro to the latest stable version .

6. Wait until the writing and verification process ends. The board will reboot and it will start beeping afterwards.

7. You may now connect to it as usual from the QGC communications pane.

Parameters file

When selecting vehicle type, click on the dropdown menu for Quadrotor x and select mRo QuadZero Kit. This will load all the appropriate parameters for your vehicle. Parameters list download

Wireless telemetry link

Once you have performed the minimum configuration you may disconnect the USB cable and proceed to use the telemetry radio for the rest of the configuration steps. With your QZ powered from the battery, wait for the Status LED on the mRo DualBand Wi-Fi Telemetry Radio to turn solid green, a Wi-Fi network will be created automatically.

Then connect your device to the mRo_wifi network using controlZero as password.

Use the following configuration settings to establish communication with your GCS software:

Mission Planner

Select UDPCl as the connection type. Enter 192.168.2.1 when prompted for the hostname, and 14550 as the remote port.

QGroundControl

Click on the Qground Logo on left top corner > Applications Settings > Comm Links > Add > Insert the following parameters:

Select the newly created connection and click connect below.

More info

For more options and details about the advanced configuration of the mRo DualBand Wi-Fi Telemetry Radio, visit:

RC receiver bind procedure

Now is a good time to bind your transmitter to the installled receiver, please follow the next steps:

1. Power your Quad Zero while holding the F/S button on the receiver. You should see the red and green LEDs ON. Release the F/S button on the receiver.
2. Put your Transmitter in Binding mode. Each TX has its method,follow the steps based on your model.
3. The LED on the receiver will flash, indicating the binding process was successful.
4. Stop the "binding" beacon on the transmitter.
5. Power cycle the Quad Zero.
6. A green LED on the receiver indicates a successful process.

If the receiver LED is flashing red, try to repeat the process. If the problem persists, check that you have the latest version of the ACCST D16 firmware on your transmitter. You can find the newest version of the firmware compatible with the receiver in the following link:

If you have a multi-protocol transmitter and are having trouble connecting to the receiver, this link provides an easy way to download the latest firmware file for your MULTI module:

MULTI-Module site

Sensor calibration, RC setup and motor direction check

Regardless of the flight stack you are running, you must perform these calibration steps to ensure a completely configured platform.

For Ardupilot:

• Accelerometer Calibration — Copter documentation

• Compass Calibration — Copter documentation

• Radio Control Calibration — Copter documentation

• RC Transmitter Flight Mode Configuration — Copter documentation

For PX4:

• Compass Calibration | PX4 User Guide

• Accelerometer | PX4 User Guide

• Radio (Remote Control) Setup | PX4 User Guide

• Flight Mode Configuration | PX4 User Guide

Final assembly steps

Motor Direction Test

Motor directions should match the following diagram:

To do this test on Mission Planner go to: Setup > Optional Hardware > Motor Test

Click on each motor to verify motor spin direction and motor order. If the motor direction is wrong, you can reverse the movement by swapping two of the three ESC to motor power leads.

For more info please visit - Connect ESCs and Motors — Copter documentation.

On QGroundControl, go to Vehicle Setup > Actuators:

Please check PX4/QGC wiki for further information, note that since v1.13 the Control Allocation feature is available: - Actuator Configuration and Testing | PX4 User Guide - Use the manual output sliders to verify correct order and spin direction.

For more information about motor directions, you can follow the next link:

Motor order diagram

Props & motors subassembly

Before installing the propellers, we strongly advise to balance them statically. Even if manufacturers label the props as pre-balanced you should double and triple check this fact experimentally using a propeller balancer tool.

Install propellers

Use 2 included M2x5mm screws per motor to secure the propeller in place. Loctite is allowed for extra security. Ensure the propellers are mounted correctly according to the previous section links.

If you have issues identifying the CW vs CCW please see Recognizing clockwise and counterclockwise propellers.

Dynamic balancing

Use the steps described above for verifying the motor direction to actuate each motor individually. We suggest to run it to 30% and 60% approximately, while holding the arm carefully with your fingers. Excessive vibration will be evident and counterweights should be placed until the results satisfy yourself.

Fly responsibly, safely and securely.

Happy flying!