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.
Furthermore, I designed a frame to mount the webcam underneath the drone. Here is a picture of the 3D printed prototype.So, I guess I can say that I am making progress :)
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 :)