# DJI F450 + RTK (Pixhawk 3 Pro)

The _DJI® Flame Wheel F450_ Quadcopter is designed for amateur aerial photography, first person view applications, and general flying entertainment. This topic provides full build and configuration instructions for using the frame with the Pixhawk 3 Pro flight controller. Additionally this build includes an RTK GPS and a distance sensor for precision positioning.

Key information:

* **Frame:** DJI Flame Wheel 450
* **Flight controller:** [Pixhawk 3 Pro](../../drone_parts/flight_controller/autopilot_pixhawk_standard/pixhawk3_pro)
* **Positioning:** RTK GPS

![](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-d080422de9843b2bde105e4f61b0f33c3f2375e8%2Ff450_setup_full.jpg?alt=media)

![](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-251806170a2ca39e6333e17d6c90af3e52e1e285%2Ff450_setup_back.jpg?alt=media)

## Parts List

* Autopilot: [Pixhawk 3 Pro](../../drone_parts/flight_controller/autopilot_pixhawk_standard/pixhawk3_pro)
* Frame: [DJI Flamewheel 450](http://www.dji.com/flame-wheel-arf)
* Motors: 3DR Iris Plus 950kv rebranded T-Motors MN2213
* ESCs: Hobbywing XRotor 35A Micro 3-6S BLHeli
* Blades: Graupner 10"x5" (You need to print [these adapters](https://drive.google.com/file/d/0B2piootk_fIKMWhIVzVPWEFGLU0/view) to be M6 compatible)
* Distance sensor: Lidar-Lite V3
* GPS: Here+ RTK GPS
* Telemetry: [3DR Telemetry](../../drone_parts/peripherals/telemetry/sik_radio)
* Battery: Roxxy LiPo - 4S, 4000mAh

In addition we use a FrSky X4R-SB 3/16ch 2.4Ghz receiver and a FrSky Taranis controller. You will also need zip ties, double sided tape, a soldering iron and a 3D printer in case you use the same Blades, for this build. The GPS mast was reused from an Intel Aero.

![F450 setup - open](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-bb45930f7e0f01e62aa602c7cbd2368f022860ea%2Ff450_setup_open.jpg?alt=media)

The _Pixhawk 3 Pro_ can be attached using the double sided tape because the IMU inside is already dampened.

In this setup the autopilot is rotated by 180 degrees so that it's easier to access the SD card. But if you rotate the base plate by 180 degrees instead, the flight controller board can be mounted facing forward. Either way works, just make sure to set the board rotation correctly in _QGroundControl_ afterwards.

## Wiring and Connections

General pinout for the Pixhawk 3 Pro can be found [here](https://drotek.gitbook.io/pixhawk-3-pro/hardware/inputs-outputs).

### Telemetry Radio

:::note The 3DR Telemetry radio used here is no longer available. Comparable alternatives can be found in [Telemetry Radios > SiK Radio](../../drone_parts/peripherals/telemetry/sik_radio). :::

The 3DR Telemetry radio does not come with a JST GH connector which the _Pixhawk 3 Pro_ uses. The pinout remains the same and just the plug needs to be changed. Use the `TELEM 1` port on the _Pixhawk 3 Pro_.

| pin | Pixhawk 3 Pro Telem 1 | 3DR Telemetry |
| --- | --------------------- | ------------- |
| 1   | VCC                   | VCC           |
| 2   | TX                    | RX            |
| 3   | RX                    | TX            |
| 4   | CTS                   | CTS           |
| 5   | RTS                   | RTS           |
| 6   | GND                   | GND           |

### Lidar-Lite V3

The pinout for the [Lidar Lite V3](../../drone_parts/peripherals/rangefinders/lidar_lite) and the _Pixhawk 3 Pro_ I2C 1 port is as follows.

| pin | Pixhawk 3 Pro I2C 1 | Lidar Lite V3    |
| --- | ------------------- | ---------------- |
| 1   | VCC                 | VCC              |
| 2   | SCL                 | - (Power enable) |
| 3   | SDA                 | - (Mode control) |
| 4   | GND                 | SCL              |
| 5   | -                   | SDA              |
| 6   | -                   | GND              |

### Here+ RTK GPS

:::note This RTK GPS has been discontinued. Alternatives can be found [here](../../drone_parts/peripherals/rtk_gps) :::

The [Here+ RTK GPS](../../drone_parts/peripherals/rtk_gps/rtk_gps_hex_hereplus) comes with an 8 pin connector suited for the Pixhawk 2. In order to use it with the _Pixhawk 3 Pro_ (or a Pixracer), a 6 pin connector has to be used and pin 6 and 7 are not needed (see below). The additional pins are for the safety button and can be attached as well if needed.

More information on the pinout can be found in [this document](http://www.hex.aero/wp-content/uploads/2016/07/DRS_Pixhawk-2-17th-march-2016.pdf), page 17.

![Setup GPS](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-e21708dadc733fa15c826948dc3b4978e7ff02fb%2Ff450_setup_gps.jpg?alt=media)

| pin | Here+ GPS   | pin | Pixhawk 3 Pro GPS |
| --- | ----------- | --- | ----------------- |
| 1   | VCC\_5V     | 1   | VCC               |
| 2   | GPS\_RX     | 2   | GPS\_TX           |
| 3   | GPS\_TX     | 3   | GPS\_RX           |
| 4   | SCL         | 4   | SCL               |
| 5   | SDA         | 5   | SDA               |
| 6   | BUTTON      | -   | -                 |
| 7   | BUTTON\_LED | -   | -                 |
| 8   | GND         | 6   | GND               |

## PX4 Configuration

General documentation on how to setup your quad in _QGroundControl_ can be found in [Basic Configuration](../../config). Specific setup instructions are provided below.

### Airframe

In the [Airframe](../../config/airframe) configuration, select the _Generic Quadcopter_ airframe (**Quadrotor x > Generic Quadcopter**).

![QGroundControl - Select Generic Quadcopter](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-d3bed089dfee73f6a8443bec053f116c57efbbf2%2Fqgc_airframe_generic_quadx.png?alt=media)

### Actuators

In the [Actuators](../../config/actuators) configuration in _QGroundControl_

* Update the vehicle geometry to match the Flamewheel 450
* Assign actuators functions to outputs as wired.
* Test the configuration using the sliders.

### RTK GPS

RTK GPS is plug and play. For more instructions see [here](../../drone_parts/peripherals/rtk_gps).

### Lidar-Lite

To enable the _Lidar-Lite V3_ (connected via I2C), the parameter [SENS\_EN\_LL40LS](../../../advanced_config/parameter_reference#SENS_EN_LL40LS) has to be set to `I2C`.

This can be done in _QGroundControl_ (see [Finding/Updating Parameters](../../advanced_config/parameters)) as shown below:

![Set SENS\_EN\_LL40LS parameter in QGC](https://4155462212-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F-LArEa7z2SPawfl3HpCD%2Fuploads%2Fgit-blob-20a7769ae5884a20c1fde60b4cf66c37e6112676%2Ff450_qgc_setup_i2c.png?alt=media)

:::note After setting the `SENS_EN_LL40LS` you will need to restart the flight controller. :::

### Others

Set the following parameters as well:

* `MAV_PROTO_VER=2`: use MAVLink protocol version 2
* `CBRK_IO_SAFETY=22027`: disable the safety button
* `EKF2_GPS_POS_X`, `EKF2_GPS_POS_Y`, `EKF2_GPS_POS_Z`: set the GPS device offset with respect to the board (NED coordinates).

### Tuning

Airframe selection sets _default_ autopilot parameters for the frame. These may be good enough to fly with, but you should tune each frame build.

For instructions on how, start from [Autotune](../../config/autotune).

## Video

@[youtube](https://youtu.be/JovSwzoTepU)
