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New historically realistic Sopwith Camel JSBSim FDM released

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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby flug » Thu Jan 09, 2014 8:50 pm

Gijs wrote in Thu Jan 09, 2014 9:42 am:Yes, Thorsten's procedure is correct. If you don't want to/can pull fgdata, you may also ask me or anyone else with commit rights to push a zipped package. Merge requests are the preferred way though.


Aha, the light dawns. I can do a merge request, I think.

And finally, please do contact Vivian to see if he agrees with your changes (assuming thatthis will overwrite the current Camel's FDM).


OK. I think this will just amount to adding a new JSBSim FDM for the Camel and not deleting anything that is already there. So it's only adding something new (a new JSBSim FDM) but not taking away anything that is already there with the YASim and UIUC FDMs. But I'll work out the details to make sure and contacting Vivian is probably a good idea regardless.

Thanks!
Last edited by flug on Fri Jan 10, 2014 7:01 am, edited 3 times in total.
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby Gijs » Fri Jan 10, 2014 4:54 pm

I've split the "JSBSim or YASim" posts to viewtopic.php?f=49&t=21780, please continue that discussion there and leave this topic for the Sopwith Camel.

@flug: sounds like a good plan. I forgot the current Camel has a YASim FDM, so yes, it will be a seperate FDM then.

Cheers,
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby flug » Mon Jan 13, 2014 7:38 pm

FYI I made a quick video showing some of the ground and water reaction effects that will be in the next version of the JSBSim Sopwith Camel:

https://www.youtube.com/watch?v=QOXPFoV-JTI

The improvements shown there include:

- Water landing, floating to the appropriate level in water
- Splashing & wake effects when gear, wings, tail, etc hit the water
- Dust effects when aircraft parts strike or drag the ground
- Terrain bumpiness (as in FG scenery data) making the a/c actually bump around, much as YASim does
- Terrain friction and rolling resistance levels varying and having an effect on the aircraft's rolling resistance

FYI this is an outgrowth of the discussion on the other thread about YASim vs JSBSim, what is good and what is missing from the various aircraft that use the two different FDMs, and so on. So I think that has been a helpful and productive discussion from my end, because it led me to think some more about the ground and water interactions in the Camel and how they might be improved and made more realistic.
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby Johan G » Tue Jan 14, 2014 2:18 pm

That is a great demonstration of what can be done in JSBSim. JSBSim just takes a bit more of "umph". Thanks! :D
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby billy_bob1916 » Tue Aug 05, 2014 5:49 pm

Hi Flug,
nice model, but I can't get it started. Can you help me?
How can I see that the magnetos are active or not? (the switches are not animated, are they?)
It's all a bit confusing!

Thanks
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby flug » Thu Jan 08, 2015 12:19 am

billy_bob1916 wrote in Tue Aug 05, 2014 5:49 pm:Hi Flug,
nice model, but I can't get it started. Can you help me?
How can I see that the magnetos are active or not? (the switches are not animated, are they?)
It's all a bit confusing!

Thanks

Billy Bob,

Sorry you're having a problem.

There are indeed two magneto switches that visually move. They are near the bottom of the dashboard and are often hidden behind some of the equipment from your initial viewpoint. You may have to change your viewpoint a bit to see them.

This is the same model (and the same problem) as the Camel that is included in the base FG distribution.

Help screen for the a/c within Flightgear says:

    Press { and } once each--so that both L and R magneto switches are in center position.
    Press and hold the s key for 1.5 seconds. It may take several tries before the engine catches.
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby flug » Mon Feb 20, 2017 8:27 pm

FYI I'm just preparing the 2.0 version of the JSBSim Sopwith Camel. A few of the updates:

- Ground effects, dust, spray, water splashing, and generally better interactions with the ground
- Crashes are handled much better, with sound effects, dust, explosion, etc. I feel like ultra- realistic crashes aren't really a focus of FG, but at least we can give folks the idea the "you just crashed -- HARD!" rather than "You just sproinged off the ground like a giant trampoline."
- Ground reactions--different rolling & sliding friction depending on the surface, bumpiness depending on surface, etc. (as described & in sample video above)
- Improved sound - especially air whooshing effect so that you can tell when approaching stall, going overspeed etc.
- And most of all a greatly refined flight dynamics model - more realistic in every respect but also smoother and more flyable

Very influential in this update is an article about work to quantify the flight behavior of a restored Camel that is running a Rhone rotary engine--a rarity these days. The article is well worth a read:

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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby Johan G » Mon Feb 20, 2017 9:21 pm

flug wrote in Mon Feb 20, 2017 8:27 pm:Very influential in this update is an article about work to quantify the flight behavior of a restored Camel that is running a Rhone rotary engine--a rarity these days. The article is well worth a read:


Interesting article. Have you considered trying to get in contact with the author? I would expect that data reduction could be quite a chore though... :roll:

Also, I wonder if the Camel could fly clean at all after reading this: :shock: :lol: :wink:
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby flug » Wed Feb 22, 2017 8:37 am

OK, I confess--I'm a bit obsessed with the Camel. But this new version is really a LOT of fun to fly . . .

If anyone wants to take a preview look this new ver. 2.0 of the JSBSim Sopwith Camel, here is the download link:

https://github.com/bhugh/SopwithCamel-JSBSim-Flightgear/archive/2.0alpha.zip

This is the 2.0alpha version. Just unzip everything into your FG/data directory. Several files go into the /docs subfolder--you'll probably want to have a look at them.

Here are some of the new features

VER 2.0
-------

* Major updates to Flight Dynamics Model, significant better fit to historically reported behavior. Went through every one of more than 60 characteristics of the Camel I've identified from historical accounts (all listed in the NOTES file in the /docs directory), tested each one, tweaked the FDM a bit here and there to put the final touches on the FDM updates I've been working on over the past two years. It's very noticeably improved from ver. 1.6 in several areas.

* Ground contact effects: Dust, dirt, wake when wheels, tail, prop, fuselage etc contact the ground or water

* Parts break: Wheels, undercarriage, & prop will break if they contact the ground with too much force. Visual, audio, & physics affects of broken parts are apparent--ie, if you hit the ground too hard the wheel breaks off and you hear it and feel it, and the aircraft behaves differently with no wheel.

* Ground/water crash behavior much improved; solved problems with JSBSim when violent ground crashes occur. Pilot is kicked out of plane in crash, explosionsound, smoke/dust clouds, (some) parts break appropriately, somewhat reasonable aircraft physics displayed @ crash (vs previous versions that tended to just 'bounce off the ground')

* Sound effects: Blip, air rushing (useful for detecting stall/overspeed), overspeed whooshing, high G creaks & ominous rumbles, landing gear and taildragger rumble, if you touch a wing it slides, water landings have their own sound effects, buffeting aloft, etc. Wheel thump on landing, tail dragging (and lifting) sounds, other sounds that help you know what's going on. Sound effects help you make a connection between what you're doing in the aircraft and the world you are interacting with, so I've tried to include sound effects that help you know what is going on with the aircraft.

* Repair aircraft after crash or parts broken: Available in Camel/Repair menu or automatically completed when appropriate choice is made in 'crash menu'.

* Improved documentation. If you haven't flown the JSBSim Camel before, be sure to read the aircraft help screen ( '?' key in FG).

* "Nudge": If landed and stuck in a field or in the countryside somewhere, and just can't quite get moving, pressing 'n' gives you a little push to get you going and unstuck.

* New 'Inspect Aircraft View' based on FG's WalkView. I quite like this because you can easily maneuver your way to any given spot around the aircraft--behind the tail, in front of the nose, beside the pilot, whatever, and just stay there. Select using 'v' and maneuver with wasd WASD and mouse for view direction.
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby Matuchkin » Wed Feb 22, 2017 11:58 pm

DFaber wrote in Sun Mar 31, 2013 10:55 am:Apart from that, the main advantage of a Fighter Pilot is Altitude and Speed, a situation well within the envelope.


Correct me if I'm mistaken, but isn't that the main advantage of a long range interceptor, high-altitude supersonic bomber, etc pilot? Aren't "fighters" divided into a myriad of categories, each with their own characteristics and small advantages? For example, the above quote may apply to the pilot of an SR-71 Blackbird or partially to the pilot of an F-14 Tomcat, but not to the pilot of an A-10c Thunderbolt (maneuverability+slow speed+protection and ruggedness), SU-35 (maneuverability+speed), F-16 (maneuverability+speed+very advanced computers), etc (these three planes are completely and utterly different from another).
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby flug » Thu Feb 23, 2017 12:07 am

Johan G wrote in Mon Feb 20, 2017 9:21 pm:
flug wrote in Mon Feb 20, 2017 8:27 pm:Very influential in this update is an article about work to quantify the flight behavior of a restored Camel that is running a Rhone rotary engine--a rarity these days. The article is well worth a read:


Interesting article. Have you considered trying to get in contact with the author? I would expect that data reduction could be quite a chore though... :roll:


That's actually a really interesting idea.

For anyone interested in the Camel or aircraft of the era, Garrison has a few other interesting articles:

http://www.flyingmag.com/sopwith/techni ... ng-sopwith

http://www.flyingmag.com/pilots-places/ ... ittle-book

http://www.airspacemag.com/history-of-f ... w-22968921

http://www.flyingmag.com/photo-gallery/ ... -creek-fly

RE: your comment about 'clean' flying, in the "Nice Little Book" article, Garrison says, "It was virtually incapable of prolonged coordinated flight". So that's something!
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby flug » Thu Feb 23, 2017 3:20 am

I came across this photo of a Camel at the top of a loop ca. 1917.

So naturally, I couldn't resist:

Image

The interesting thing is, in the 1917 photo the horizon is clearly visible. So from that reference point we can tell exactly where the pilot is in his loop and exactly the plane's attitude with respect to the horizontal plane.

You can see that our 1917 pilot is just barely past the top of his loop and his right wing is dropping quite a bit. This is a well known feature of Camel loops due to the gyroscopic effect and other factors. In flying a loop, you have to counteract that tendency with rudder and ailerons, but even at best you're still going to have a bit of a drop.

So, you can see that I'm dropping the right wing in exactly the same way at exactly the same point in the loop, with the JSBSim Camel.

This isn't something that I did on purpose, or that I had to try time and time again to duplicate. (This was the second try, actually--the first was one quite similar but I didn't like the backdrop.)

It's just what the Camel does--both in FlightGear and in real life!
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby wlbragg » Thu Feb 23, 2017 5:41 am

@flug, nice!

Iadded the variant tag to see the JSBSim version along with the YASSim version.

As in
Code: Select all
<sim include="help-jsbsim.xml">
      <variant-of>sopwithCamel-YASim-Bombable</variant-of>
      <description type="string">Sopwith Camel 1F.1 (JSBSim, Historically Accurate FDM &amp; Weapons, Bombable-compatible, ver 2.0)</description>
      <author type="string">AJ MacLeod, Vivian Meazza, Brent Hugh (Historically accurate JSBSim FDM &amp; weapons, Bombable compatibility)</author>
      <status type="string">V2.0: Production, guns work</status>
      <rating>
         <FDM type="int">4.2</FDM>
         <systems type="int">3.5</systems>
         <cockpit type="int">4</cockpit>
         <model type="int">5</model>
      </rating>


Also, I guess I don't have or it couldn't figure out the path to
Code: Select all
<keyboard include="../Generic/WalkView/walk-view-keys.xml">

So to get it to work at all I had to get rid of the include?
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby AndersG » Thu Feb 23, 2017 8:18 am

The WalkView lives in fgdata/Aircraft/Generic/WalkView/ so the "full" path from Aircraft/... should be used. I guess this include predates separate aircraft directories.
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Re: New historically realistic Sopwith Camel JSBSim FDM rele

Postby flug » Sat Feb 25, 2017 12:28 pm

Thanks all for the feedback. Here is the next candidate release that includes fixes for all the issues you have mentioned plus a lot more:

https://github.com/bhugh/SopwithCamel-J ... .0beta.zip

You can also download the full Bombable package, which includes the 2.0beta JSBSim Camel as well as much more:

https://github.com/bhugh/Bombable/archive/4.6beta.zip

What's new & improved?

- Rembrandt ready (and looks GREAT in Rembrandt - thanks to the developers of the Camel in the main FG distribution, who updated the models etc)
- Engine management improvement, more realistic
- Several more effects and refinement of effects - ground friction & bumpiness, parts breaking, etc
- Prop disk! It looks cool, plus helps you see what's going on with the engine
- More improvements to the sound design; sounds that help you know what's going on with the engine and the aircraft
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