Ubuntu LTS/Debian Linux上开发环境的搭建

The supported/tested Linux OS versions for PX4 development are Ubuntu Linux LTS 18.04 (Bionic Beaver) and 20.04 (Focal Fossa). These allow you to build for the most PX4 targets (NuttX based hardware, Qualcomm Snapdragon Flight hardware, Linux-based hardware, Simulation).

我们提供了Bash脚本来方便你根据不同的平台安装开发环境：

ubuntu.sh：安装 Gazebo 9 和 jMAVSim 仿真器以及/或者 NuttX/Pixhawk 工具。不包含FastRTPS所依赖的工具。
ubuntu_sim_ros_melodic.sh: Installs ROS "Melodic" and PX4 on Ubuntu 18.04 LTS (and later).

The scripts have been tested on clean Ubuntu 18.04 LTS and Ubuntu 20.04 LTS installations. They may not work as expected if installed "on top" of an existing system, or on a different Ubuntu release.

本说明将在下面解释如何下载并使用这些脚本。

Gazebo，JMAVSim 与 NuttX（Pixhawk）编译目标

使用ubuntu.sh这个脚本来安装开发环境以支持Gazebo 9和jMAVSim仿真器，以及/或者NuttX/Pixhawk工具链。

执行步骤：

下载 PX4 源代码：

 bash
 git clone https://github.com/PX4/Firmware.git --recursive

在bash shell中不带参数地运行ubuntu.sh来安装所有的依赖工具：
```
 bash
 bash ./Tools/setup/ubuntu.sh
```

* 在安装过程中确认并通过所有的提示。
* 你可以通过传输参数`--no-nuttx` 和 `--no-sim-tools` 来跳过 nuttx 和/或 仿真器工具的安装。

完成后重新启动计算机。

你也可以从 PX4 源码库（/Tools/setup/）手动下载 ubuntu.sh 与 requirements.txt 文件并运行 ubuntu.sh：
wget https://raw.githubusercontent.com/PX4/Firmware/master/Tools/setup/ubuntu.sh
wget https://raw.githubusercontent.com/PX4/Firmware/master/Tools/setup/requirements.txt
bash ubuntu.sh

备注：

PX4需要跟Gazebo 7, 8, 或者 9一起工作，该脚本使用gazebosim.org instructions来安装Gazebo9。
如果你正在使用ROS工作，那么请遵循ROS/Gazebo的介绍来安装（它是自动转安装的，作为ROS安装的一部分）。

你可以通过确认gcc的版本来验证Nuttx的安装：

  $arm-none-eabi-gcc --version

  arm-none-eabi-gcc (GNU Tools for Arm Embedded Processors 7-2017-q4-major) 7.2.1 20170904 (release) [ARM/embedded-7-branch revision 255204]
  Copyright (C) 2017 Free Software Foundation, Inc.
  This is free software; see the source for copying conditions.  There is NO
  warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

Raspberry Pi

获取用于树莓派 Raspberry Pi 的构建工具链：

从PX4源码仓库下载ubuntu.sh 和requirements.txt：
wget https://raw.githubusercontent.com/PX4/Firmware/master/Tools/setup/ubuntu.sh
wget https://raw.githubusercontent.com/PX4/Firmware/master/Tools/setup/requirements.txt
在终端中运行ubuntu.sh，获取一般的依赖模块：
```
 bash
 bash ubuntu.sh --no-nuttx --no-sim-tools
```
然后根据下面的描述安装ARMv7交叉编译器(GCC或者Clang)。

GCC

The official Raspberry Pi toolchains are not supported as PX4 has requires C++14 (which they do not support).

Ubuntu provides a set of pre-compiled toolchains that you can use instead. Install these with the terminal command:

sudo apt-get install -y gcc-arm-linux-gnueabihf g++-arm-linux-gnueabihf

These package contains GCC/G++ 7.4.0 at time of writing. To test the toolchain, please execute:

arm-linux-gnueabihf-gcc -v
arm-linux-gnueabihf-g++ -v

Clang

First install GCC (needed to use clang).

We recommend you to get clang from the Ubuntu software repository as follows:

sudo apt-get install clang

Example below for building PX4 firmware out of tree, using CMake.

cd <PATH-TO-PX4-SRC>
mkdir build/px4_raspberrypi_default_clang
cd build/px4_raspberrypi_default_clang
cmake \
-G"Unix Makefiles" \
-DCONFIG=px4_raspberrypi_default \
-UCMAKE_C_COMPILER \
-DCMAKE_C_COMPILER=clang \
-UCMAKE_CXX_COMPILER \
-DCMAKE_CXX_COMPILER=clang++ \
../..
make

本地编译

Additional developer information for using PX4 on Raspberry Pi (including building PX4 natively) can be found here: Raspberry Pi 2/3 Navio2 Autopilot.

ROS/Gazebo

This section explains how to install ROS/Gazebo ("Melodic") for use with PX4.

To install the development toolchain:

在bash shell中下载脚本：
wget https://raw.githubusercontent.com/PX4/Devguide/master/build_scripts/ubuntu_sim_ros_melodic.sh

运行脚本：

 bash
 bash ubuntu_sim_ros_melodic.sh 随着脚本的运行，可能需要根据提示进行确认。

注：

ROS Melodic 已经默认跟Gazebo9一起安装了。
你的catkin（ROS编译系统）工作空间已经创建在~/catkin_ws/中。
脚本中使用的指令来自于ROS的wiki的"Melodic" Ubuntu page。

高通骁龙飞控（Snapdragon Flight）

在 PX4 用户指南 中提供了高通骁龙飞控的安装说明：

Fast RTPS installation

eProsima Fast RTPS 是 RTPS（Real Time Publish Subscribe 实时发布订阅）协议的 C++ 实现库。通过 RTPS/ROS2 接口：PX4-FastRTPS 桥接使用 FastRTPS，允许与 Offboard 组件共享 PX4 uORB 话题。

Follow the instructions in Fast RTPS Installation to install it.

附加工具

After setting up the build/simulation toolchain, see Additional Tools for information about other useful tools.

后续步骤

Once you have finished setting up the environment, continue to the build instructions.

Ubuntu/Debian Linux