Michael,

I read your post about creating a hardware-in-the-loop simulation using JSBsim and was hoping to do some collaboration. I am working on the same issue, but I have more of an aerdynamics background than a programming one. I have an RC-sized aircraft model (in JSBsim) but am stuck trying to program an autopilot and create an electric engine model. Care to trade some configuration files?

Tom

Micheal, (do you prefer Mike?)

I think we are on parallel paths. Here's what I have accomplished:

1. I installed JSBsim alone, no Flight Gear.
2. I ran some of their pre-created scripts of a Cessna 172 and collected position, velocity, attitude, and inertial data.
3. The data was used to simulate GPS and inertial sensors in Matlab (with added noise and other errors).

The results of this work was a successful IMU-based navigation system that I cannot talk about because my partner and I are not releasing it open source.

My next task is to develop the autopilot system. I created a FDM of a rascal UAV using aerodynamic data from a published paper. I have not tested it yet because I am stuck trying to learn the scripting language of JSBsim.

Eventually, I would like a simulation that could be used to develop autopilot control laws, test autopilot hardware-in-the-loop, and be used for a groundstation flight planning tool. It seems that JSBsim could fit very well into that picture.

Right now I am stuck because there are no pre-created electric engine models in JSBsim, and I don't know enough to create one. I am also struggling to understand the scripting system to a point that I can create an autopilot.

What do you know about electric motors?

I'll send you the FDM file for the Rascal UAV in a post once I get home.

Tom

Mike,

The reason my partner and I aren't making our IMU open source is because we think we can make some money on it. The performance is a step above anything else available now to the amature.

I will send you the data I collected and the scripts tonight when I get home from work. If you could get an electric model working in JSBsim, I would love to get a copy!

Tom

rascal.xml
flightdata.csv

Mike,

We feel that there are two markets we want to target. The first is data logging/telemetry where highly-accurate position/velocity/attitude data is required. The second is the acrobatic autopilot market, which currently doesn't exist. I'm not sure how many people out there want to have their aircraft do autonomous acrobatics, but I think there are a few. But this is the original reason my partner and I got started on this project.

We haven't done much with the IMU board we have now. We need to get some programming work done to see if the processor we have (Arduino) has enough horsepower to run our algorithms. We did do some simple attitude calculation using just gyro integration and it got lost after just a few seconds of manouvering! But we haven't collected any raw data from them yet. I hope to do that after we purchase a GPS. (They are out of stock.)

I would like to get all those parameters you listed in your post. I would love to model the battery drain and everything, but I don't know how realistic that is. Anything you can find would be great!

I will let you know once we collect some IMU data.

Tom

Mike,

I haven't gotten far enough to actually try running with the rascal file! I will try to look at the file when I get home from work.

Tom

Mike,

I think I found the problem. Try this file.

Tom

rascal.xml

Thanks Mike! I will try running with the init file you gave tonight.

Tom

Mike,

I fixed the configuration file. Now the sim runs, but I don't think there is anything to make it stop... :)

Tom

rascal.xml

Hi Mike,

Sorry for badgering you. I am Tejeshwi, currently working on a project at ETH, Zurich. I am trying to simulate a Multiplex Funjet powered by an electric engine on JSBSim. Through the conversations you had with people, i learned that you had tried a similar simulation with Rascal 110 powered by an electric engine. Can you share your experience with me. Can you also share the script file with me? My aircraft crashes on flying. Hope you shall oblige me by doing the needful.

Cheers,
Tejeshwi