Is it possible to fly the drone with closed QGC?

I am new to PX4. I have a holybro X500 drone, which comes with pixhawk 6C. I did all the calibrations in QGroundControl. As I don’t have a RC, I use a (connection through USB) joystick to fly the drone. One telemetry is installed on the drone, and the other is connected to the computer.

  1. So far, I can fly my drone only when QGC is open on my computer. If I close QGC then it does not arm (using the joystick) even.

  2. I have to control the drone through the Simulink interface. In Simulink we have “Serial …” block where commands could be sent from the computer to the drone. But if I open QGC and run Simulink, it shows error “Unable to create a communication link with the serial port.” In this case my telemetry is connected to the drone but does not receive a command from the Simulink.

Sorry, maybe my questions are complicated.

Any help/idea is appreciated.

Hi @Bek, I don’t know what exact setup you’re running, but QGC is not needed to fly a drone with the PX4 Autopilot.

The vehicle has to detect a Ground Control Station (GCS), an RC input or a compatible development SDK.

One way to use a Joystick setup is through a GCS, like QGC. When you have QGroundControl open and you also have a Joystick connected to the computer, it can use it to forward the inputs to the drone using the telemetry link. I’m not sure if this is what you’re doing, but it sounds like. You can use a third party application to achieve the same (it has to be compatible with the required protocols).

If you have automatic serial connection on QGC enabled, which it is by default, and open another application that also wants to open the same serial connection it’s normal that it fails to do so, as serial connections can’t be shared between applications. This is what happens in your number 2 scenery.

I would recommend you to properly set up the failsafe actions for telemetry and RC loss on QGC before you start testing different setups, so you can ensure that you won’t lose the drone.

Then I would also recommend you to read the following documentation: