A digital control system model of the pixhawk quadrotor was constructed in scicoslab along with a continuous model of the quadrotor dynamics (the visual model is an arducopter). The user can input the guidance commands to the autopilot through sliders. As the video shows, the yaw response it not optimal, which also happens in the actual system. Using the mavsim Scicoslab toolbox (https://github.com/openmav/mavsim/) , the model can be simulated and then, once the system has been correctly identified, the dynamics can be linearized. The linear model of the system makes the problematic modes clear and aids in designing an improved controller.
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Here are the options I see for running mavsim on windows:
1. You can delete the openscenegraph visualization block and replace it with a scope for now.
2. We can get the jsbsimcomm block properly working for the quadrotors. I have an arducopter jsbsim model that I created for this but haven't checked everything is working. I did add the 4 motor rpm inputs, but might take some more work. With this you could use the udp as you suggested. Have you had a chance to try this with the JSBSim demos?
3. If you have some idea how to get windows dll's to work properly with cmake we can try to tackle the windows cmake build.
I've improved the wiki to address these issues and help you guys out:
https://github.com/openmav/mavsim/wiki/Tutorials
https://github.com/openmav/mavsim/wiki/Build-from-Source
I've added the pixhawk quadrotor example to the Tutorial page and added the hint about creating the /usr/local/share directory if it doesn't exist for package installation. As you are going through this process if you feel anything is unclear or would help other people feel free to contribute to the wiki.
Try this before installing the package:
sudo mkdir -p /usr/local/share
You really are better off not installing the package. Since the quad stuff is in development right now not all of the demos will be accessible through the installed toolbox. The recommended way is to run:
./autobuild.sh -> in source build
Then after it finishes building:
From within the mavsim top source direction where the scilab.ini file is:
scicoslab
This will start scicoslab using the ini file and automatically load the toolbox.
It will also start you in the quadrotor project as this is what I have set in the scilab.ini file.
To start the pixhawk example type:
exec pixhawkLinearAnalysis.sce
This will show you the analysis that we've done so far on the design.
To see the scicoslab simulation type:
scicos pixhawk.cos
This will start scicos, the block diagram and simulation environment.
When scicos loads click run at the top of the diagram.
I'm trying to build it from src but seems their git server is down..
Its best to build from source since I haven't included all the quad stuff in the deb package yet. It's easy to build on ubuntu/ debian though.
Ixx, Iyy, Izz for the pixhawk team since we don't have the 3d cad model yet we just approximated using a solid sphere 8cm radius approx. with parallel axis theorm to offset the cm below the motors. 3d modelling software obviously would be the best way.
The mavsim scicoslab toolbox provides communication with the jsbsim flight dynamics, and hardware in the loop via the mavlink protocol. This was written in C++ so you would have to compile those parts on windows. The openscenegraph part is already optional. I just don't have any good windows testers so far. You would have to install cmake and I'd help you through the obstacles.
The current dynamics have been verified by the pixhawk guys and these gains flew on their quadrotor. The force models were based on various papers. You can find all the equations in mavsim/theory.
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