Update README.md (Qground install)

@@ -5,6 +5,23 @@
 
 # px4 toolchain install
 
+참고 사이트:https://docs.px4.io/master/en/dev_setup/dev_env.html
+```
+$ git clone https://github.com/PX4/firmware.git --recursive
+$ cd /firmware
+$ bash./Tools/setup/ubunth.sh
+$ sudo reboot now
+```
+
+# QgroundControl install
+
+```
+$ sudo apt-get remove modemanager –y
+$ sudo apt install gstreamer1.0-plugins-bad gstreamer1.0-libav gstreamer1.0-gl -y
+$ wget https://s3-us-west-2.amazonaws.com/qgroundcontrol/latest/QGroundControl.AppImage
+$ chmod +x ./QGroundControl.AppImage
+$ ./QGroundControl.AppImage
+```
 
 # GPS-SPoofing 구현
 ```