Re: [Flightgear-devel] c172p with terrain
On mardi 11 novembre 2008, Anders Gidenstam wrote: > On Tue, 11 Nov 2008, gerard robin wrote: > > In addition to it there is a drag when the gear (down) is IN the water > > , i remember that Vivian couldn't take off the Catalina, since the gear > > were down. > > I may understand that you don't know the JSBSim features/ressources. > > I think that was me. But it wasn't the gear - I had forgot to release the > handbrake (a.k.a. mooring :). Which will be updated since now we have that nice external_reactions features :) > > But seriously, ground interaction in FlightGear is a weak spot of JSBSim. > I'll try to look into it (note, no promise on the time scale, though..). Yes it can be improved, not only JSBSim is involved, i know that we have a lot of problem with aircrafts on Carrier with YASIm for instance the F-14 (groundcache bug ? ) With JSBSim we have that stupid ground reaction force due to pitch, (was said by Dave on the JSBSim-devel ) > > Cheers, > > Anders - currently working on an aircraft with no gears (really :). Cheers -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On Tue, 11 Nov 2008, gerard robin wrote: > In addition to it there is a drag when the gear (down) is IN the water , i > remember that Vivian couldn't take off the Catalina, since the gear were > down. > I may understand that you don't know the JSBSim features/ressources. I think that was me. But it wasn't the gear - I had forgot to release the handbrake (a.k.a. mooring :). But seriously, ground interaction in FlightGear is a weak spot of JSBSim. I'll try to look into it (note, no promise on the time scale, though..). Cheers, Anders - currently working on an aircraft with no gears (really :). -- --- Anders Gidenstam WWW: http://www.gidenstam.org/FlightGear/ - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mardi 11 novembre 2008, Melchior FRANZ wrote: > * gerard robin -- Tuesday 11 November 2008: > > A gear with a variable size ? > > Huh? You suggest to put terrain.nas into CVS, and when you > get suggestions for how to solve the problems properly, you > put them all down while ignoring that terrain.nas doesn"t > fulfill any of your requirements either. > > It doesn't support "gear with variable size" (whatever that > is), it doesn't work for AI aircraft, it is useless for > determining if an aircraft should sink. (No, a Concorde > doesn't sink if the nose is above water, as long as the > tyres aren't. ;-) That is not the purpose of the talk, however you should know that with JSBSim we can animate an control any behavior of any model in any situation, with only that poor and tricky terrain.nas. I have been able to demonstrate what can be done ( Catalina for instance ) and if we want, we could simulate a progressive siking of the Concorde when the nose is in the water, gear down or gears up. With gear down it is easy to show that the AC can have the following behavior: it don't walk on the sea, every model that i have done makes the difference. In addition to it there is a drag when the gear (down) is IN the water , i remember that Vivian couldn't take off the Catalina, since the gear were down. I may understand that you don't know the JSBSim features/ressources. On my side i have not found, yet, the limits of what can be done with it. > > So what are you really asking for? A way to find out whether > a particular coordinate is solid ground or water? Like > geodinfo()? Which I've written for that purpose? > > m. > Coming back to the main topic: If you try the Rescue Op with the S-51, you will notice that the rope can have a variable size and can be moved in order to stay vertical ( due to gravity) it becomes independent of the helo behavior which can have pitch and roll, any 'extra' gear defined ( was your proposal) should have the same rope behaviour. With AI => an hybrid car which goes floating on water or run on wheel on solid ground, without any acknowledge of which terrain is under (there is no FDM) Cheers -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
* gerard robin -- Tuesday 11 November 2008: > A gear with a variable size ? Huh? You suggest to put terrain.nas into CVS, and when you get suggestions for how to solve the problems properly, you put them all down while ignoring that terrain.nas doesn"t fulfill any of your requirements either. It doesn't support "gear with variable size" (whatever that is), it doesn't work for AI aircraft, it is useless for determining if an aircraft should sink. (No, a Concorde doesn't sink if the nose is above water, as long as the tyres aren't. ;-) So what are you really asking for? A way to find out whether a particular coordinate is solid ground or water? Like geodinfo()? Which I've written for that purpose? m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mardi 11 novembre 2008, Melchior FRANZ wrote: > * gerard robin -- Wednesday 05 November 2008: > > In addition to it, with YASIm which is supposed to include > > that feature, i am unable to control my helicoptere rescue > > operation according to the terrain which is under, with > > water we could understand but with solid the rescued man > > is digging the earth :) > > So my next update will include (again) that nasal script. > > Why don't you just add another gear, one that doesn't touch > the ground? Then you get the terrain type reported, and it's > even the terrain under the winch "gear", rather than the > totally pointless terrain under the helicopter's nose (or > wherever the reference point is). > > m. A gear with a variable size ? -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mardi 11 novembre 2008, Melchior FRANZ wrote: > * gerard robin -- Saturday 08 November 2008: > > Is it so difficult, to include within FG, the code which > > gives the information, or at least, to include as generic > > the 'famous" Nasal script ?? > > > > May be any idea which is not coming from you is bad :) > > That's funny. So you have forgotten that the code in terrain.nas > is basically *my* code? I had posted it as sample code to the list I was not talking about the idea of the nasal script content. I know that it is an idea of Cesar :) giving to Cesar what is owned by Cesar ( is the translation of a usual French ). I am talking about the idea to get within a property included into FG the terrain in order to answer to AI animation request and any other Animation with or without FDM, though with YSAIm we don't have that property. You know. YASIm it is that FDM which can be used with helicopter. If you don't trust me, look at .. for instance the bo105 or the S-51... Oh by the way S-51 wants for the rescue animation a property with terrain. > > > http://www.mail-archive.com/flightgear-devel%40lists.sourceforge.net/msg124 >33.html > > and you just took it and put it in a loop. But even if it's > my code, I still think it's just a hack around a missing > JSBSim feature. I suggest to submit the feature instead. ;-) > > m. > Cheers -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
* gerard robin -- Wednesday 05 November 2008: > In addition to it, with YASIm which is supposed to include > that feature, i am unable to control my helicoptere rescue > operation according to the terrain which is under, with > water we could understand but with solid the rescued man > is digging the earth :) > So my next update will include (again) that nasal script. Why don't you just add another gear, one that doesn't touch the ground? Then you get the terrain type reported, and it's even the terrain under the winch "gear", rather than the totally pointless terrain under the helicopter's nose (or wherever the reference point is). m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
* gerard robin -- Saturday 08 November 2008: > Is it so difficult, to include within FG, the code which > gives the information, or at least, to include as generic > the 'famous" Nasal script ?? > > May be any idea which is not coming from you is bad :) That's funny. So you have forgotten that the code in terrain.nas is basically *my* code? I had posted it as sample code to the list http://www.mail-archive.com/flightgear-devel%40lists.sourceforge.net/msg12433.html and you just took it and put it in a loop. But even if it's my code, I still think it's just a hack around a missing JSBSim feature. I suggest to submit the feature instead. ;-) m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
* gerard robin -- Wednesday 05 November 2008: > Not ripping, keeping, .. since that feature is necessary, out of, and without > > any FDM. > As far as i know, (i could be wrong and stupid) , an AI object is not FDM > dependent, but, it can be property related. Your "generic" terrain.nas wouldn't work for AI aircraft. m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
* Jon S. Berndt -- Thursday 06 November 2008: > Well, that would require JSBSim to maintain a database for the physical > properties (friction, etc.) of the terrain underneath the aircraft. No. You'd just have to extend JSBSim.cxx so that it queries the ground cache for every gear. From there it can get all the terrain information cheaply. YASim does this, it also uses the friction values, and slightly modifies the terrain elevation according to the bumpiness value before it's used by the FDM. Try a YASim aircraft (e.g. the dhc2W) and leave the runway. Taxi over grass and into a forest. You'll "feel" the bumpiness and see it on the gear animation. The values are also interesting for sound effects. If you slide the bo105 over concrete, then the noise is louder than over grass or ice. m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On samedi 08 novembre 2008, Detlef Faber wrote:
> Am Samstag, den 08.11.2008, 12:26 +0100 schrieb gerard robin:
> > On samedi 08 novembre 2008, Melchior FRANZ wrote:
> > > * gerard robin -- 11/5/2008 4:27 PM:
> > > > Though, that nasal "Terrain" script could be part of the FG generic
> > > > nasal script , won't it be useful elsewhere (AI animation ? for
> > > > instance)
> > >
> > > This script continously updates a property which tells if the
> > > aircraft's origin (usually the nose, sometimes other points) is over
> > > solid ground or water. This is really a "random" point, and whether the
> > > aircraft's nose is over water or not doesn't usually mean much.
> > >
> > > What would be useful is to know whether contact points (especially
> > > landing gear) are over water. But this is something that the FDM glue
> > > code has to care for (JSBSim.cxx). It can query everything we know
> > > about the terrain beneath from the ground cache, just like YASim.
> > > That's a sample of what info is available about any terrain (~ texture)
> > > type:
> > >
> > > { light_coverage: 0, bumpiness: 0.5999,
> > > load_resistance: 1e+30, solid: 0,
> > > names: [ "Lake", "Pond", "Reservoir", "Stream", "Canal" ],
> > > friction_factor: 1, rolling_friction: 1.5
> > > }
> > >
> > > Would be nice if JSBSim would consider the ground properties in the
> > > gear code, but it should at least publish those values that are needed
> > > for sinking effects or rumbling sound.
> > >
> > > terrain.nas is only a workaround for this omission. If you want to
> > > know about terrain properties at other points, just use the geodinfo()
> > > function directly (but not too often, to avoid expensive terrain
> > > intersection tests).
> > >
> > > m.
> >
> > Is it it on purpose that you deviate my explanation , or you don't you
> > understand what i said ?
> >
> > I Don't said that JSBSim devel wont include these information, with a
> > specific development in it .
> >
> > I only said that the information in anycase is missing when why are not
> > using any FDM, AI model don't use it (wad my first remark), and missing
> > when we are within YASIm which is suppose to have it ( was my second
> > remark ).
>
> I think it is undestandable that the ground properties are not queried
> while the Aircraft's gears are high up in the Air. They are only of
> interest when the gear is on the ground.
>
> > YES, missing when we are using YASim , i want to improve my rescue
> > animation and avoid that the rescued person is not digging solid.
> > WHERE is the property which say that the aircraft is on solid or on
> > water ?
>
> I could use this information for the walker too. The current approach
> with geo.elevation has some drawbacks (e.g passing beneath bridges isn't
> possible).
I don't know which system is being used with geodinfo (nasal) , i don't have
any difficulties when passing beneath bridges.
> Glazmax suggested in the forum to use submodels and query the impact
> report. This should provide info wether the ground is solid or not
> (=water). I haven't done much on this topic recently, but believe this
> is could be a solution for both of us.
Yes, i like simple stuff, i am not sure i will use submodels only for this :)
>
> > May be you don't know... but the rescue op im talking about, is
> > with helicopter and helicopter is using YASIm FDM
> >
> >
> > Cheers
>
>
Cheers
--
Gérard
http://pagesperso-orange.fr/GRTux/
J'ai décidé d'être heureux parce que c'est bon pour la santé.
Voltaire
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Re: [Flightgear-devel] c172p with terrain
Am Samstag, den 08.11.2008, 12:26 +0100 schrieb gerard robin:
> On samedi 08 novembre 2008, Melchior FRANZ wrote:
> > * gerard robin -- 11/5/2008 4:27 PM:
> > > Though, that nasal "Terrain" script could be part of the FG generic nasal
> > > script , won't it be useful elsewhere (AI animation ? for instance)
> >
> > This script continously updates a property which tells if the aircraft's
> > origin (usually the nose, sometimes other points) is over solid ground
> > or water. This is really a "random" point, and whether the aircraft's
> > nose is over water or not doesn't usually mean much.
> >
> > What would be useful is to know whether contact points (especially
> > landing gear) are over water. But this is something that the FDM glue
> > code has to care for (JSBSim.cxx). It can query everything we know
> > about the terrain beneath from the ground cache, just like YASim.
> > That's a sample of what info is available about any terrain (~ texture)
> > type:
> >
> > { light_coverage: 0, bumpiness: 0.5999,
> > load_resistance: 1e+30, solid: 0,
> > names: [ "Lake", "Pond", "Reservoir", "Stream", "Canal" ],
> > friction_factor: 1, rolling_friction: 1.5
> > }
> >
> > Would be nice if JSBSim would consider the ground properties in the
> > gear code, but it should at least publish those values that are needed
> > for sinking effects or rumbling sound.
> >
> > terrain.nas is only a workaround for this omission. If you want to
> > know about terrain properties at other points, just use the geodinfo()
> > function directly (but not too often, to avoid expensive terrain
> > intersection tests).
> >
> > m.
>
> Is it it on purpose that you deviate my explanation , or you don't you
> understand what i said ?
>
> I Don't said that JSBSim devel wont include these information, with a
> specific development in it .
>
> I only said that the information in anycase is missing when why are not using
> any FDM, AI model don't use it (wad my first remark), and missing when we are
> within YASIm which is suppose to have it ( was my second remark ).
>
I think it is undestandable that the ground properties are not queried
while the Aircraft's gears are high up in the Air. They are only of
interest when the gear is on the ground.
> YES, missing when we are using YASim , i want to improve my rescue animation
> and avoid that the rescued person is not digging solid.
> WHERE is the property which say that the aircraft is on solid or on water ?
I could use this information for the walker too. The current approach
with geo.elevation has some drawbacks (e.g passing beneath bridges isn't
possible).
Glazmax suggested in the forum to use submodels and query the impact
report. This should provide info wether the ground is solid or not
(=water). I haven't done much on this topic recently, but believe this
is could be a solution for both of us.
>
> May be you don't know... but the rescue op im talking about, is with
> helicopter and helicopter is using YASIm FDM
>
>
> Cheers
>
>
>
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Re: [Flightgear-devel] c172p with terrain
On samedi 08 novembre 2008, gerard robin wrote:
> On samedi 08 novembre 2008, Melchior FRANZ wrote:
> > * gerard robin -- 11/5/2008 4:27 PM:
> > > Though, that nasal "Terrain" script could be part of the FG generic
> > > nasal script , won't it be useful elsewhere (AI animation ? for
> > > instance)
> >
> > This script continously updates a property which tells if the aircraft's
> > origin (usually the nose, sometimes other points) is over solid ground
> > or water. This is really a "random" point, and whether the aircraft's
> > nose is over water or not doesn't usually mean much.
> >
> > What would be useful is to know whether contact points (especially
> > landing gear) are over water. But this is something that the FDM glue
> > code has to care for (JSBSim.cxx). It can query everything we know
> > about the terrain beneath from the ground cache, just like YASim.
> > That's a sample of what info is available about any terrain (~ texture)
> > type:
> >
> > { light_coverage: 0, bumpiness: 0.5999,
> > load_resistance: 1e+30, solid: 0,
> > names: [ "Lake", "Pond", "Reservoir", "Stream", "Canal" ],
> > friction_factor: 1, rolling_friction: 1.5
> > }
> >
> > Would be nice if JSBSim would consider the ground properties in the
> > gear code, but it should at least publish those values that are needed
> > for sinking effects or rumbling sound.
> >
> > terrain.nas is only a workaround for this omission. If you want to
> > know about terrain properties at other points, just use the geodinfo()
> > function directly (but not too often, to avoid expensive terrain
> > intersection tests).
> >
> > m.
>
> Is it it on purpose that you deviate my explanation , or you don't you
> understand what i said ?
>
> I Don't said that JSBSim devel wont include these information, with a
> specific development in it .
>
> I only said that the information in anycase is missing when why are not
> using any FDM, AI model don't use it (wad my first remark), and missing
> when we are within YASIm which is suppose to have it ( was my second
> remark ).
>
> YES, missing when we are using YASim , i want to improve my rescue
> animation and avoid that the rescued person is not digging solid.
> WHERE is the property which say that the aircraft is on solid or on water
> ?
>
> May be you don't know... but the rescue op im talking about, is with
> helicopter and helicopter is using YASIm FDM
>
>
> Cheers
AND in order to answer the point 1 and why not the point 2 ( without being
obliged to modify YASim)
Is it so difficult, to include within FG, the code which gives the
information, or at least, to include as generic the 'famous" Nasal script ??
May be any idea which is not coming from you is bad :)
Cheers
--
Gérard
http://pagesperso-orange.fr/GRTux/
J'ai décidé d'être heureux parce que c'est bon pour la santé.
Voltaire
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Re: [Flightgear-devel] c172p with terrain
On samedi 08 novembre 2008, Melchior FRANZ wrote:
> * gerard robin -- 11/5/2008 4:27 PM:
> > Though, that nasal "Terrain" script could be part of the FG generic nasal
> > script , won't it be useful elsewhere (AI animation ? for instance)
>
> This script continously updates a property which tells if the aircraft's
> origin (usually the nose, sometimes other points) is over solid ground
> or water. This is really a "random" point, and whether the aircraft's
> nose is over water or not doesn't usually mean much.
>
> What would be useful is to know whether contact points (especially
> landing gear) are over water. But this is something that the FDM glue
> code has to care for (JSBSim.cxx). It can query everything we know
> about the terrain beneath from the ground cache, just like YASim.
> That's a sample of what info is available about any terrain (~ texture)
> type:
>
> { light_coverage: 0, bumpiness: 0.5999,
> load_resistance: 1e+30, solid: 0,
> names: [ "Lake", "Pond", "Reservoir", "Stream", "Canal" ],
> friction_factor: 1, rolling_friction: 1.5
> }
>
> Would be nice if JSBSim would consider the ground properties in the
> gear code, but it should at least publish those values that are needed
> for sinking effects or rumbling sound.
>
> terrain.nas is only a workaround for this omission. If you want to
> know about terrain properties at other points, just use the geodinfo()
> function directly (but not too often, to avoid expensive terrain
> intersection tests).
>
> m.
Is it it on purpose that you deviate my explanation , or you don't you
understand what i said ?
I Don't said that JSBSim devel wont include these information, with a
specific development in it .
I only said that the information in anycase is missing when why are not using
any FDM, AI model don't use it (wad my first remark), and missing when we are
within YASIm which is suppose to have it ( was my second remark ).
YES, missing when we are using YASim , i want to improve my rescue animation
and avoid that the rescued person is not digging solid.
WHERE is the property which say that the aircraft is on solid or on water ?
May be you don't know... but the rescue op im talking about, is with
helicopter and helicopter is using YASIm FDM
Cheers
--
Gérard
http://pagesperso-orange.fr/GRTux/
J'ai décidé d'être heureux parce que c'est bon pour la santé.
Voltaire
-
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Re: [Flightgear-devel] c172p with terrain
* gerard robin -- 11/5/2008 4:27 PM:
> Though, that nasal "Terrain" script could be part of the FG generic nasal
> script , won't it be useful elsewhere (AI animation ? for instance)
This script continously updates a property which tells if the aircraft's
origin (usually the nose, sometimes other points) is over solid ground
or water. This is really a "random" point, and whether the aircraft's
nose is over water or not doesn't usually mean much.
What would be useful is to know whether contact points (especially
landing gear) are over water. But this is something that the FDM glue
code has to care for (JSBSim.cxx). It can query everything we know
about the terrain beneath from the ground cache, just like YASim.
That's a sample of what info is available about any terrain (~ texture)
type:
{ light_coverage: 0, bumpiness: 0.5999,
load_resistance: 1e+30, solid: 0,
names: [ "Lake", "Pond", "Reservoir", "Stream", "Canal" ],
friction_factor: 1, rolling_friction: 1.5
}
Would be nice if JSBSim would consider the ground properties in the
gear code, but it should at least publish those values that are needed
for sinking effects or rumbling sound.
terrain.nas is only a workaround for this omission. If you want to
know about terrain properties at other points, just use the geodinfo()
function directly (but not too often, to avoid expensive terrain
intersection tests).
m.
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Re: [Flightgear-devel] c172p with terrain
On mercredi 05 novembre 2008, Martin Spott wrote: > gerard robin wrote: > > I will need some space in my URL, so i will have to remove that file. > > Just in case, why don't you simply just put those files there which > require to be changed - instead of the entire aircraft ? > > Cheers, > Martin. Well, i have built the package with the files which are only involved. Within data/Aircraft/c172p replace =>c172p-set.xml =>c172p.xml add that stupid file =>terrain.nas The link is http://pagesperso-orange.fr/GRTux/c172p.tar.gz Cheers -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On Thu, 2008-11-06 at 02:39 +0100, gerard robin wrote: > Only the case of an emergency landing on water with gear down could be > usefully modeled, ( depending on the speed, the resistance could very high > which can make the nose over) There is a NACA paper on this for, NACA-RM-L9K02a. They tried dropping large scale model DC-4 and DC-6s into a pool and analyzed the results. I recall they decided gear up, flaps down was the best approach. http://ntrs.nasa.gov/search.jsp?R=99950&id=3&qs=No%3D100%26Ne%3D25%26N%3D289 Ron - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On jeudi 06 novembre 2008, Jon S. Berndt wrote: > > Hello Jon > > > > I do not confuse both, > > -First an accurate development within the FDM itself, and > > here, you know better than i do, what must/could be done. > > > > -Second an external simple information which is given by FG > > => the terrain which is under, solid or water. > > > > That information which is simple, will be mainly usefull for AI model > > which do not use any FDM, or useful to build some specific animation like > > rescue operation that i referred to. > > > > Cheers > > > > -- > > Gérard > > http://pagesperso-orange.fr/GRTux/ > > Well, that would require JSBSim to maintain a database for the physical > properties (friction, etc.) of the terrain underneath the aircraft. I don't > consider that to be something that the FDM should account for. That sounds > like something that is in the domain of FlightGear or SimGear. However, > JSBSim can expose via properties the friction coefficients that could be > changed to reflect the type of terrain. I agree > For modeling landing on water OR > land, that might be a little bit harder to model. Here, with seaplane we could use the same process which is being used by the Boeing314 or the Catalina, when hull is in contact with water. Hull_resistance AND Step_lift AND follow = In that case everything is right, the actual JSBSim gives us any flexibility we want. Only the case of an emergency landing on water with gear down could be usefully modeled, ( depending on the speed, the resistance could very high which can make the nose over) > > Jon > Cheers -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
> Hello Jon > > I do not confuse both, > -First an accurate development within the FDM itself, and > here, you know better than i do, what must/could be done. > > -Second an external simple information which is given by FG > => the terrain which is under, solid or water. > > That information which is simple, will be mainly usefull for AI model > which do not use any FDM, or useful to build some specific animation like > rescue operation that i referred to. > > Cheers > > -- > Gérard > http://pagesperso-orange.fr/GRTux/ Well, that would require JSBSim to maintain a database for the physical properties (friction, etc.) of the terrain underneath the aircraft. I don't consider that to be something that the FDM should account for. That sounds like something that is in the domain of FlightGear or SimGear. However, JSBSim can expose via properties the friction coefficients that could be changed to reflect the type of terrain. For modeling landing on water OR land, that might be a little bit harder to model. Jon - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On jeudi 06 novembre 2008, Jon S. Berndt wrote: > > I don't pretend that is not be in the FDM , which should be more > > accurate according to the terrain ( runway, grass, sand, ... water > > and so on), i know that Jon intend to include it into JSBSim. > > I don't know if I understand this problem completely, but I am guessing > that we would need to expose via properties the dynamic and static > coefficients of friction for each landing gear (and structural contact > point)? True? > > I think that would be the best approach. > > Jon Hello Jon I do not confuse both, -First an accurate development within the FDM itself, and here, you know better than i do, what must/could be done. -Second an external simple information which is given by FG => the terrain which is under, solid or water. That information which is simple, will be mainly usefull for AI model which do not use any FDM, or useful to build some specific animation like rescue operation that i referred to. Cheers -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
> I don't pretend that is not be in the FDM , which should be more accurate > according to the terrain ( runway, grass, sand, ... water and > so on), i know that Jon intend to include it into JSBSim. I don't know if I understand this problem completely, but I am guessing that we would need to expose via properties the dynamic and static coefficients of friction for each landing gear (and structural contact point)? True? I think that would be the best approach. Jon - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On Wed, Nov 5, 2008 at 10:34 PM, gerard robin <[EMAIL PROTECTED]> wrote: > > As far as i know, (i could be wrong and stupid) , an AI object is not FDM > dependent, but, it can be property related. > > However, i am probably alone, here, to think that generic FG feature useful. > > Again, > tell me how i can build > an AI object , => an hybrid car which goes floating on water or run on wheel > on solid ground, without any acknowledge of which terrain is under (there is > no FDM) Ideally, every AI object should in fact have its own fdm, and an AI pilot which is only providing control inputs that a real pilot would. I don't think FDM takes a lot of cpu resources, so when we have dedicated AI server(s) that could in fact be realized. For now, I think you are right. If this will be used by more aircraft, it is in fact easier to manage having it in a common place. -- Csaba - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mercredi 05 novembre 2008, Martin Spott wrote: > gerard robin wrote: > > I only wonder if we won't get some adventage, within FG itself, to know > > with a property, if there is water or solid under (with nasal script or > > some code) I had recently in mind, to create animation with AI model > > which are terrain dependent. > > Well, it probably is advantagwous to have such feature _now_ and Yes > also carries the disadvantage that someone has to care for cleanly > ripping all this back out after the FDM has improved. Not ripping, keeping, .. since that feature is necessary, out of, and without any FDM. As far as i know, (i could be wrong and stupid) , an AI object is not FDM dependent, but, it can be property related. However, i am probably alone, here, to think that generic FG feature useful. Again, tell me how i can build an AI object , => an hybrid car which goes floating on water or run on wheel on solid ground, without any acknowledge of which terrain is under (there is no FDM) > This was just a proposal of mine, I'll happily leave the related > decisions to those who are willing to do the work ;-) > > Cheers, > Martin. -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
gerard robin wrote: > I only wonder if we won't get some adventage, within FG itself, to know with > a > property, if there is water or solid under (with nasal script or some code) > I had recently in mind, to create animation with AI model which are terrain > dependent. Well, it probably is advantagwous to have such feature _now_ and also carries the disadvantage that someone has to care for cleanly ripping all this back out after the FDM has improved. This was just a proposal of mine, I'll happily leave the related decisions to those who are willing to do the work ;-) Cheers, Martin. -- Unix _IS_ user friendly - it's just selective about who its friends are ! -- - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mercredi 05 novembre 2008, gerard robin wrote: > On mercredi 05 novembre 2008, Martin Spott wrote: > > gerard robin wrote: > > > Though, that nasal "Terrain" script could be part of the FG generic > > > nasal script , won't it be useful elsewhere (AI animation ? for > > > instance) > > > > Well, to my point of view - and I know I'm not the sole person having > > this in mind - it's a bit unfortunate to hammer workarounds into stone > > that actually in search for a totally different solution. > > > > As I understand from Heiko's explanation, the purpose of the respective > > script is to work around a feature which is missing from the FDM being > > used here. Therefore I'd vote _not_ to make this script part of the > > 'generic' script collection, but instead lobby on the FDM people to > > implement the missing parts. > > > > Cheers, > > Martin. > > I don't pretend that is not be in the FDM , which should be more accurate > according to the terrain ( runway, grass, sand, ... water and so > on), i know that Jon intend to include it into JSBSim. > > I only wonder if we won't get some adventage, within FG itself, to know > with a property, if there is water or solid under (with nasal script or > some code) I had recently in mind, to create animation with AI model which > are terrain dependent. > Scenery and AI are not using any FDM which could solve it . > > Cheers In addition to it, with YASIm which is supposed to include that feature, i am unable to control my helicoptere rescue operation according to the terrain which is under, with water we could understand but with solid the rescued man is digging the earth :) So my next update will include (again) that nasal script. Cheers. -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mercredi 05 novembre 2008, Martin Spott wrote: > gerard robin wrote: > > Though, that nasal "Terrain" script could be part of the FG generic nasal > > script , won't it be useful elsewhere (AI animation ? for instance) > > Well, to my point of view - and I know I'm not the sole person having > this in mind - it's a bit unfortunate to hammer workarounds into stone > that actually in search for a totally different solution. > > As I understand from Heiko's explanation, the purpose of the respective > script is to work around a feature which is missing from the FDM being > used here. Therefore I'd vote _not_ to make this script part of the > 'generic' script collection, but instead lobby on the FDM people to > implement the missing parts. > > Cheers, > Martin. I don't pretend that is not be in the FDM , which should be more accurate according to the terrain ( runway, grass, sand, ... water and so on), i know that Jon intend to include it into JSBSim. I only wonder if we won't get some adventage, within FG itself, to know with a property, if there is water or solid under (with nasal script or some code) I had recently in mind, to create animation with AI model which are terrain dependent. Scenery and AI are not using any FDM which could solve it . Cheers -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
gerard robin wrote: > Though, that nasal "Terrain" script could be part of the FG generic nasal > script , won't it be useful elsewhere (AI animation ? for instance) Well, to my point of view - and I know I'm not the sole person having this in mind - it's a bit unfortunate to hammer workarounds into stone that actually in search for a totally different solution. As I understand from Heiko's explanation, the purpose of the respective script is to work around a feature which is missing from the FDM being used here. Therefore I'd vote _not_ to make this script part of the 'generic' script collection, but instead lobby on the FDM people to implement the missing parts. Cheers, Martin. -- Unix _IS_ user friendly - it's just selective about who its friends are ! -- - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mercredi 05 novembre 2008, gerard robin wrote: > On mercredi 05 novembre 2008, Martin Spott wrote: > > gerard robin wrote: > > > I will need some space in my URL, so i will have to remove that file. > > > > Just in case, why don't you simply just put those files there which > > require to be changed - instead of the entire aircraft ? > > > > Cheers, > > Martin. > > Yes, as far i remember, > -the set file > -the FDM > -and, an additional Nasal script are only involved Though, that nasal "Terrain" script could be part of the FG generic nasal script , won't it be useful elsewhere (AI animation ? for instance) > I will look at it. -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mercredi 05 novembre 2008, Martin Spott wrote: > gerard robin wrote: > > I will need some space in my URL, so i will have to remove that file. > > Just in case, why don't you simply just put those files there which > require to be changed - instead of the entire aircraft ? > > Cheers, > Martin. Yes, as far i remember, -the set file -the FDM -and, an additional Nasal script are only involved I will look at it. -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
gerard robin wrote: > I will need some space in my URL, so i will have to remove that file. Just in case, why don't you simply just put those files there which require to be changed - instead of the entire aircraft ? Cheers, Martin. -- Unix _IS_ user friendly - it's just selective about who its friends are ! -- - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
On mardi 28 octobre 2008, Heiko Schulz wrote: > > Hello, > > You know that the JSBSim FDM Aircrafts can make the > > difference between water > > and solid, the models only wants a little update which > > include a terrain.nas > > nasal script. > > Every JSBSim models, that i have done which are in CVS do > > have that feature. > > For my home usage i had done a c172p which takes that > > feature, i just have > > updated it from the CVS version. > > You may want it, it is available here, if wanted, it could > > be committed . > > > > http://pagesperso-orange.fr/GRTux/c172p.tar.gz > > > > Cheers > > > > -- > > Gérard > > Sounds fine- would be great if this standart aircraft have this feature! > > Cheers > HHS > I guess, that anybody who was interested on it, has yet downloaded it . I will need some space in my URL, so i will have to remove that file. Cheers. -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] c172p with terrain
> Hello, > You know that the JSBSim FDM Aircrafts can make the > difference between water > and solid, the models only wants a little update which > include a terrain.nas > nasal script. > Every JSBSim models, that i have done which are in CVS do > have that feature. > For my home usage i had done a c172p which takes that > feature, i just have > updated it from the CVS version. > You may want it, it is available here, if wanted, it could > be committed . > > http://pagesperso-orange.fr/GRTux/c172p.tar.gz > > Cheers > > -- > Gérard Sounds fine- would be great if this standart aircraft have this feature! Cheers HHS - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
[Flightgear-devel] c172p with terrain
Hello, You know that the JSBSim FDM Aircrafts can make the difference between water and solid, the models only wants a little update which include a terrain.nas nasal script. Every JSBSim models, that i have done which are in CVS do have that feature. For my home usage i had done a c172p which takes that feature, i just have updated it from the CVS version. You may want it, it is available here, if wanted, it could be committed . http://pagesperso-orange.fr/GRTux/c172p.tar.gz Cheers -- Gérard http://pagesperso-orange.fr/GRTux/ J'ai décidé d'être heureux parce que c'est bon pour la santé. Voltaire - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
