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Aircraft Development Tutorial Step by Step

Questions and discussion about creating aircraft. Flight dynamics, 3d models, cockpits, systems, animation, textures.

Re: Aircraft Development Tutorial Step by Step

Postby openflight » Sun Jun 21, 2020 1:29 am

Personally, I think that most people would start out with simple texturing first.

....

Either of these provide for a much lower barrier to entry than walking people right away through the whole process of creating an aircraft from scratch - in fact, for the latter, it would kinda make sense to use a template based wizard instead, where people can specify an aribitrary -set.xml file to serve as a template for creating a new -set.xml - this could be done for different parts of the structure (fdm, 3d model, nasal, systems etc)


Having done some more work on 3D files, I will elaborate here. The final structure of the document is not finalized.

In the last chapter, we transferred an aircraft model to the test aircraft folder, without changing much of the files and folders along the way. Is it possible to create a minimal template of an aircraft in Flight Gear which only serves to load and fly the model? It turns out that the answer is yes, and helps understand the folder structure for aircraft for FG.

Creating a template from stratch turned out to be problemmatic - the model would not load, so I took the top down approach, and copied the entire T38 folder to a separate folder simply named "T" for short. The next step was deleting all the files that were not critical to load and run the model, and removing animations, as the animations for the model would not apply since we would be creating a new basic 3D model such as a cube for testing, maybe a stealth delta shape with wheels,

Inside the folder named T:

The following folders were not changed:

Engines

Models

These files were not changed:

T38.xml - the flight dynamics model, jbsim format. This is referred to and used only by the T38-SET.xml file, the main settings file for the model.

The following files were changed as follows:

T38-set.xml

(removed a lot of the animations and references to other files that would have prevented the model from loading properly, these will be detailled later)

I used the T38 model to check if everything was loading and running properly. Then I substituted the T38 with a simple 3D block created in Wings 3D , which is one of the easiest model tools around.

Keep in mind this is just an exercise, neither the file format nor the quality of the model here may be acceptable as a final product, however for learning how to create and install a 3D model, this is very useful, as well as the template files provided.
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Creating an aircraft template

Postby openflight » Fri Jun 26, 2020 3:56 am

Creating and aircraft template, one that can be downloaded and used to develop a new aircraft, is a goal I have had for some time. It is only now that I have completely understood how to do this. I believe many more modellers would create aircraft for Flight Gear if the had an easy way of modelling the aircraft.

A template file would consist of a running aircraft that could take off and fly, with a 3D test object and a sample aircraft that could be substituted. I wish I had this many years ago when I was starting out.

The text from my write up is here:

We have seen how to copy an existing aircraft and load another model aircraft into it. This leaves many extra folders and files that are not needed. These files are confusing.

Another way is to start creating aircraft is for Flight Gear is to use a template aircraft, one with minimal files and independent of any other aircraft. This is especially useful for testing out the 3D model made and how it appears and also if animations work. The template will be an aircraft with working engine and flying model that flies and is controllable.

You can download the template aircraft directly from (source to be given).

This is how I created the template:

Lets create a template from start

1. Download this file :

http://ftp.igh.cnrs.fr/pub/flightgear/f ... aft-1.9.1/

The T-38 model named T38_20081023.zip

2. Unzip the files into the FlightGear/Aircraft folder.

3. Rename the T38 folder as template.

4. Inside the template folder, find the file named T-38-set.xml and rename it to template-set.xml

If you attempt to load the aircraft, it will show as follows in the FGRUN flight launcher. (model not found)


In the t38 set file to

<model>

<path>Aircraft/T38/Models/T38-model.xml</path>

</model>


<model>

<path>Aircraft/template/Models/T38-model.xml</path>

</model>

The model loads and runs, but there are many other files that in the template folder that are confusing and irrelevant. These will be explained and deleted later if necessary.

First, subsitute a model into the template folder by copying a model, say liftingbody.3ds into the template/models folder and changing the following line in the aircraft/template/models/T38:

T38-model.xml

<PropertyList>

<path>T38.ac</path>


<PropertyList>

<path>liftingbody.3ds</path>

The model should load, and run

Next: cleaning up the template aircraft to its basics, for use.




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Re: Aircraft Development Tutorial Step by Step

Postby tdammers » Fri Jun 26, 2020 7:50 pm

I'd publish it as a blog post, on your own account; if it's deemed good enough, someone will likely approach you about copying it into the wiki. And if not, it'll still be out there, and can be pointed to.
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Re: Aircraft Development Tutorial Step by Step

Postby openflight » Sat Jun 27, 2020 1:01 am

Ummm. yes, yes. I may submit a draft document and they can review that.
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