1. Pre-Flight Mission Planning
DROTAG.x relies on Ardupilot messages to trigger the camera and add tags to it, so it is worth taking the time to learn how to efficient mission planning. At Airborne Projects we do the planning of the mission and waypoint upload through Mission Planner.
Although planning a mission in Mission Planner or others is outside the scope of this manual there are some details that need to be taken into account. Specifically the “Photo every (est)“.
Other parameters and tutorials on Mission Planner can be found on this link. We seriously advise our customers to get comfortable with tutorials as this part of the flight is the only one which is not automated.
1.1 Time Between Pictures or “Photo every (est)”
The “Photo every (est)” parameter should not be less than 1.6 seconds unless you have the compatible hot shoe installed and configured. There is no limitation with the hot shoe configured and installed in your camera. If the time between triggers in your mission plan is less than 1.6 second the trigger order will be not be issued by DROTAG.x. It is important to note that this time limit can be broken by flight conditions, like wind. In this case it may happen that the number of pictures predicted does not match the actual taken. This limitation would happen in any case due to the camera’s write speed.
There are many ways around the “Photo every (est)” parameter, each with their own drawbacks. Below, you can find the available approaches in order of best to worse:
1. Slightly Slower Flight – Your mission will take longer to fly but all your pictures will be with the desired Ground Resolution (pixel/cm) which is the normal requirement parameter when doing aerial photography.
2. Higher Altitude – When flying higher you can sacrifice Ground Resolution to obtain pictures with bigger area covered. With bigger area covered in each picture, the more time you have to take next one. You may hit a hard limit on both the altitude as well as on the Ground Resolution requirements.
3. Overlap or Sidelap Reduction – It may be possible, due to end use of the collected pictures to reduce the sidelap or overlap of the pictures so that they are less frequent. This increases the time between pictures.
4. 2 Passes – You can program the mission to perform the same flight path twice with a slight offset to get the same overlap at the cost of extended mission time. This option is not available automatically by Mission Planner and needs manually creating the mission waypoints.
2. Pre-Flight Quickly Checklist
Included in the DROTAG.x package is a checklist to perform before the flight. This checklist is not mandatory but is a good practice to guarantee that your field work will be flawlessly done.
1. Verify camera and cables are secure and away from the propeller’s path;
2. Verify if the hot shoe parameters, including mission, are correct for the setup;
3. Power On the camera and check battery;
4. (Optional) Make sure that the camera settings are correct;
5. Power On the UAV general power;
6. Wait for GPS Lock;
7. The DROTAG.x system is ready-to-go! Have a nice flight!
3. Pre-Flight Checklist – Detailed Explanation
1. Verify camera and cables are secure – This item is responsible for no damage or loss of equipment. Not getting pictures is bad, destroying your hardware is worse.
2. Power on the camera and check battery – The camera should be powered before the DROTAG.x board because the software running will not see any camera available. If theDROTAG.x board is powered before camera it can be reset and it will try to check the camera again. Powering on the camera is useful to check if there is any error in the camera. The battery check serves as a situational awareness reminder. It is up to the operator to ensure the camera has enough battery to perform the flight.
3. (Optional) Verify camera settings are correct – This is optional because the camera settings should not change between flights. You should observer this item if the camera settings were previously changed. Incorrect picture settings can make DROTAG.x under-perform severely because some settings can cause the camera to have big delays between trigger and picture shooting, blocking DROTAG.x while flight is carried on normally. Incorrect picture settings can also lead to blurry, dark or white pictures. Standard guidelines to camera settings are given in the Further Information tab.
4. Power On the UAV general power – This will power all the system as well as the DROTAG.x board allowing it to take control of the camera.
5. Wait for GPS Lock – The Ardupilot needs to acquire a 3D Fix to have a position estimate. The position estimate of Ardupilot is what enables coordinates tagging into the picture. The way you check for this event is not the same in all the Ardupilot/GPS receivers. On the Pixhawk when the LED is green the GPS is locked and this item is passed.
6. DROTAG.x System is Ready-to-Go! – The operator can take-off and start the mission knowing the camera system is working.