Hello diydrones community :)
As part of my studies I started working on this 3DR X8+ octocopter almost 4 months ago.
At this point it must be said that this is my very first experience with drones.
Nevertheless, the project I am working on is quite ambitious.
The final goal is to have a drone takeoff a
nd land from an Unmanned Surface Vehicle (USV).
In light of the fact that I have only 2 months left until my visa expires (I am a student from Germany), that goal probably wont be accomplished by me. However, I try to get as much done as possible.
So far, I have used MAVProxy and DroneKit (awesome tool!) to program and fly my desired flight pattern.
Furthermore, I made use of the SITL simulator to test every python module I wrote before taking the drone out to the field.
The flight pattern looks somehow like this:
The drone shall takeoff, fly towards an object of interest, perform a ROI flight, fly back to the USV, and land there.
I do admit that it took me quite a while to read up on the topic, but thanks to you, 3DR, and the wiki documentation I could achieve some successes.
Now that the mission itself is working, I am focusing on the main difficulty and that is landing on the top deck of the USV.
My idea is to develop a vision system that can be used to determine the relative position of the USV in the final stage of the aforementioned mission.
Therefore, I bought the required equipment (Odroid U3, Logitech C920, etc.) and followed this instructions to establish the connection between the companion computer and the Pixhawk.
However, there is one thing that bothers me and that I just can't explain... maybe you guys can help me out once again.
The python module I wrote will be executed when the flight mode is changed to ALT_HOLD.
Whenever the user changes back to LOITER he will gain manual control.
Now, for some reason I have a varying delay between flipping the switch to ALT_HOLD and the drone showing reaction.
In fact, the props begin to spin only after 15 to 84 seconds. When I did connect to the Odroid via PuTTY I also noticed that the change of the flight mode is equally displayed with a major delay. At this point, I am clueless.
Some further information: The Odroid connects to the telem1 port of the Pixhawk. The telem1 baud rate is set to 1500.
The link cable is built out of a FTDI cable and the DF13 6 Pin connector.
I'd really like to hear your suggestions, comments, or clues :)