4 Replies Latest reply on Jun 18, 2018 7:15 AM by xiaoyao

    Is there any aux pins that can send triggering signal to the camera?

    xiaoyao

      Hi Everyone,

       

      From the Odroid C1 - Pixhawk Flight Controller Hardware Project I got that Pixhawk autopilot have aux pins that can sending triggering signal to the camera, which is descibed as follows:

      Sending triggering signal from Pixhawk autopilot

      The Pixhawk autopilot is capable of sending a triggering signal to the bluefox camera(s). In the following section it is shown how the Pixhawk and the Odroid are set up such that the Pixhawks sends simultaneously two trigger pulses to two bluefox cameras such that these two bluefox cameras capture image frames at the same time. To accomplish this task from a software perspective, there are several steps that must be considered. They are separated into three parts:

      1. Starting camera trigger app on Pixhawk
      2. Establishing service call that sends message to Pixhawk to start triggering
      3. Adapt camera driver to send ready-for-trigger signal

      In the following section these steps are explained in more detail. It is important to note that the mavros node as introduced in the preceding section must be started otherwise it is not possible to communicate with the Pixhawk.

      Starting camera trigger app on Pixhawk

      The camera trigger app is part of the Pixhawk firmware and the source code can be found here. In the file camera_trigger_params.c the desired parameters can be set. In this example two bluefox cameras should be triggered simultaneously. The two AUX pins 1 and 2 of the Pixhawk should be used to send the trigger signal. Thus the parameter TRIG_PINS is set to 12. To start the camera trigger app at boot, create the file extra.txt on the SD card and write the following:

      camera_trigger start

      Even though the camera trigger app is started at boot, it should start to send the trigger signal only after the service call from the Odroid has arrived. Please note, the camera trigger app on the Pixhawk does not only send electric trigger pulses it also sends a timestamp message that corresponds to the time instance when the trigger pulse was sent. This message is forwarded to the Odroid C1 and then published in the ROS network via the application mavros that was introduced before.

      Is there any aux pins from the intel aero computer board that can send triggering signal to the camera?

       

      Thanks!