intel d435i驱动暂时不支持ubuntu20，因为内核版本是5.4太高了。
ubuntu 18.04:
https://github.com/IntelRealSense/librealsense/blob/master/doc/installation.md
*********************Prerequisites
1. Make Ubuntu Up-to-date:
sudo apt-get update && sudo apt-get upgrade && sudo apt-get dist-upgrade
2. Download/Clone librealsense github repository:
git clone https://github.com/IntelRealSense/librealsense.git
or
git clone https://gitee.com/xxJian/librealsense
3. Prepare Linux Backend and the Dev. Environment:
3.1 Navigate to librealsense root directory to run the following scripts.
3.2 Install the core packages required to build librealsense binaries and the affected kernel modules:
sudo apt-get install git libssl-dev libusb-1.0-0-dev pkg-config libgtk-3-dev
Distribution-specific packages:
sudo apt-get install libglfw3-dev libgl1-mesa-dev libglu1-mesa-dev
cd librealsense
./scripts/install_glfw3.sh
***********************************************************
这个过程太慢，需要手动修改install_glfw3.sh中，把https://github.com/glfw/glfw.git替换为https://gitee.com/xxJian/glfw
***********************************************************
3.3 Run Intel Realsense permissions script from librealsense root directory:
./scripts/setup_udev_rules.sh
3.4 Build and apply patched kernel modules for:
./scripts/patch-realsense-ubuntu-lts.sh
3.5 TM1-specific:
echo 'hid_sensor_custom' | sudo tee -a /etc/modules
4. Building librealsense2 SDK
mkdir build && cd build
cmake ../ -DBUILD_EXAMPLES=true
sudo make uninstall && make clean && make && sudo make install
5. Reconnect the Intel RealSense depth camera and run: realsense-viewer to verify the installation.
到这里可以测试了
6. 远程桌面（失败了）
sudo apt install xrdp
sudo systemctl enable xrdp
7. 查看文件夹大小
du -sh
8. 打包整个librealsense，留底
sudo apt install p7zip-full p7zip-rar
7z a librealsense.7z librealsense
9. 复制压缩包到U盘
sudo fdisk -l，可以看到设备名称为/dev/sdb1，大小29.8G，文件格式FAT32。
sudo mount /dev/sdb1 /mnt
sudo cp librealsense.7z /mnt
sudo umount /mnt