Re: [Flightgear-devel] AI Carrier with Aircraft, and the last JSBSim version

2008-08-28 Thread Bill Galbraith
 


 With Catapult it is less a  problem, with answering time 
 delay, i mean it should work.
 Catapults features need only to know the starting position 
 with a more or less value precision: a carrier with 20 km 
 speed does 5.6 meter per second = 0.50 1/10 sec = 0.05 1/100 sec
 
 The heading won't be  a difficulty,  the  heading of the 
 carrier  is not quickly moving.
 

I haven't done much with FG or JSBSim lately, but thought I'd add my $0.02
worth, since I'm working on this stuff on a 'real' simulator.

Not all carriers shoot off at the carrier's heading. Some US carriers
(sorry, I can't name names) are left of carrier heading, up to 8 degrees.
Some secondary cats (cats 3 and 4) are off even more. (I think they even
show some of that in Top Gun).

Plus, the force applied is in carrier axes (with the aforementioned offset),
not in aircraft body axes. The force must be translated into body axis so
that it tracks down the cat track. That way, if you are lined up poorly on
the cat, it straightens you out. 

The carrier is most likely not going to be changing heading or speed during
a launch, but it should be accounted for. With a high-seas condition, the
boat is rock, roll, and heave a lot. Traps are REALLY difficult when the
seas are rough. They probably have to time a shot off a cat to coincide with
an up motion, so that you don't get shot into a wave.

Bill


-
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=100url=/
___
Flightgear-devel mailing list
Flightgear-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/flightgear-devel


Re: [Flightgear-devel] AI Carrier with Aircraft, and the last JSBSim version

2008-08-26 Thread gerard robin
On lun 25 août 2008, Jon S. Berndt wrote:
  Hello,
 
 ...
 
  In order to get these data into the JSB FDM, the crude  solution could
  be, to
  include the yasim calculation part into JSBSim.
 
  I feel that won't be the more elegant solution, and i am not sure that
  Jon
  would agree on it.  :)
 
  Though, i am not aware, about the FG source organisation, i dare that
  question:
 
  Won't it be possible to calculate and to give on request ( when we are
  close
  to a  Carrier ) these data.
  I mean, the cats and wires positions ?
 
  Cheers
  --
  Gérard
  http://pagesperso-orange.fr/GRTux/

 As posted by Dave in the JSBSim mailing list, I firmly agree: determining
 carrier location and orientation should not be an FDM specific function.
 This needs to be more configurable from the FlightGear side, so any FDM can
 take that information and do with it what it needs to do cat/hook ops.

 Jon




YES, the problem won't be  technical, but mainly a policy problem.

Since that feature is included into YASim , I fear  the answer (again, i got 
it..),  for model which want carrier features, YASim  answer the 
request  :).

I hope that the prize to do it,  will not be too high.

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=100url=/
___
Flightgear-devel mailing list
Flightgear-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/flightgear-devel


Re: [Flightgear-devel] AI Carrier with Aircraft, and the last JSBSim version

2008-08-26 Thread gerard robin
On mar 26 août 2008, gerard robin wrote:
 On lun 25 août 2008, Jon S. Berndt wrote:
   Hello,
  
  ...
  
   In order to get these data into the JSB FDM, the crude  solution could
   be, to
   include the yasim calculation part into JSBSim.
  
   I feel that won't be the more elegant solution, and i am not sure that
   Jon
   would agree on it.  :)
  
   Though, i am not aware, about the FG source organisation, i dare that
   question:
  
   Won't it be possible to calculate and to give on request ( when we are
   close
   to a  Carrier ) these data.
   I mean, the cats and wires positions ?
  
   Cheers
   --
   Gérard
   http://pagesperso-orange.fr/GRTux/
 
  As posted by Dave in the JSBSim mailing list, I firmly agree: determining
  carrier location and orientation should not be an FDM specific function.
  This needs to be more configurable from the FlightGear side, so any FDM
  can take that information and do with it what it needs to do cat/hook
  ops.
 
  Jon

 YES, the problem won't be  technical, but mainly a policy problem.

 Since that feature is included into YASim , I fear  the answer (again, i
 got it..),  for model which want carrier features, YASim  answer the
 request  :).

 I hope that the prize to do it,  will not be too high.

 Cheers

Sorry, I answer  to myself, :)
Though, more the prize is high, more the chances to obtain it, are large

More seriously.
Won't it be possible to get with a generic Nasal script?

with the closest Carrier:
The Catapults position  with  heading.
The wire positions Left/right position.

Like we have a generic aar.nas (though it is not usable for me, too generic )  
we could have, a carrier.nas.

I am not a Nasal expert, so can't do it.
However,  there is so many Nasal  expert here   ... :)

Regards

-- 
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=100url=/
___
Flightgear-devel mailing list
Flightgear-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/flightgear-devel


Re: [Flightgear-devel] AI Carrier with Aircraft, and the last JSBSim version

2008-08-26 Thread Csaba Halász
On Tue, Aug 26, 2008 at 11:23 AM, gerard robin [EMAIL PROTECTED] wrote:
 On mar 26 août 2008, gerard robin wrote:
 On lun 25 août 2008, Jon S. Berndt wrote:
  As posted by Dave in the JSBSim mailing list, I firmly agree: determining
  carrier location and orientation should not be an FDM specific function.
  This needs to be more configurable from the FlightGear side, so any FDM
  can take that information and do with it what it needs to do cat/hook
  ops.

I might be misunderstanding something here, but currently the generic
groundcache code returns catapults and wires:

// Return the nearest catapult to the given point
// pt in wgs84 coordinates.
double get_cat(double t, const SGVec3d pt,
   SGVec3d end[2], SGVec3d vel[2]);

// Return 1 if the hook intersects with a wire.
// That test is done by checking if the quad spanned by the points pt*
// intersects with the line representing the wire.
// If the wire is caught, the cache will trace this wires endpoints until
// the FDM calls release_wire().
bool caught_wire(double t, const SGVec3d pt[4]);

// Return the location and speed of the wire endpoints.
bool get_wire_ends(double t, SGVec3d end[2], SGVec3d vel[2]);

// Tell the cache code that it does no longer need to care for
// the wire end position.
void release_wire(void);

The FDM only has to use this information. I have done that for the
wires, but I don't understand the catapult model so couldn't do the
cats.

-- 
Csaba/Jester

-
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=100url=/
___
Flightgear-devel mailing list
Flightgear-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/flightgear-devel


Re: [Flightgear-devel] AI Carrier with Aircraft, and the last JSBSim version

2008-08-26 Thread gerard robin
On mar 26 août 2008, Melchior FRANZ wrote:
 * gerard robin -- 8/26/2008 11:23 AM:
  Won't it be possible to get with a generic Nasal script?
 
  with the closest Carrier:
  The Catapults position  with  heading.
  The wire positions Left/right position.

 Could be problematic. The involved subsystems are handled at different
 places in the main loop, which can easily cause synchronization problems.
 (aircraft - FDM update, carrier position - AI update, Nasal loops -
 event handler, visuals - view manager update). As Czaba wrote, letting
 the FDM do that (in connection with the fgfs interface code) is more
 promising.


SNIP
 m.



Yes and No,

You are right with the wires, if their is any time delay i won't work 
correctly., and the AC will stop out of the carrier area.

With Catapult it is less a  problem, with answering time delay, i mean it 
should work.
Catapults features need only to know the starting position with a more or 
less value precision: a carrier with 20 km speed does 5.6 meter per second  
= 0.50 1/10 sec = 0.05 1/100 sec

The heading won't be  a difficulty,  the  heading of the carrier  is not 
quickly moving.




-- 
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=100url=/
___
Flightgear-devel mailing list
Flightgear-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/flightgear-devel


Re: [Flightgear-devel] AI Carrier with Aircraft, and the last JSBSim version

2008-08-25 Thread Jon S. Berndt
 Hello,

...

 In order to get these data into the JSB FDM, the crude  solution could
 be, to
 include the yasim calculation part into JSBSim.
 
 I feel that won't be the more elegant solution, and i am not sure that
 Jon
 would agree on it.  :)
 
 Though, i am not aware, about the FG source organisation, i dare that
 question:
 
 Won't it be possible to calculate and to give on request ( when we are
 close
 to a  Carrier ) these data.
 I mean, the cats and wires positions ?
 
 Cheers
 --
 Gérard
 http://pagesperso-orange.fr/GRTux/


As posted by Dave in the JSBSim mailing list, I firmly agree: determining
carrier location and orientation should not be an FDM specific function.
This needs to be more configurable from the FlightGear side, so any FDM can
take that information and do with it what it needs to do cat/hook ops.

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=100url=/
___
Flightgear-devel mailing list
Flightgear-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/flightgear-devel


[Flightgear-devel] AI Carrier with Aircraft, and the last JSBSim version

2008-08-24 Thread gerard robin
Hello,

There is,  into the recent FDM JSBSim update, a new huge feature  with is 
the External_Forces, this gives us, a lot of new facilities for model 
development, like mooring rope, chutes, catapults, hook, mules  and so on.
Each external_force can be defined BODY or LOCAL.

Working on an Aircraft (Crusader) with Carrier (Foch) I am looking for the 
right solution to get the positions of the  Carrier with its components 
catapults and wires.

Into FG source, we can find some code which gives, regarding the AI, the 
positions., global x-y-z, and lat lon.   I have found it  for Carrier and 
Tankers (very useful for refuel), and probably there for any AI models.  
However there is nothing  regarding the Carriers components, catapults and 
wires positions.
Into YASim the positions of each component, catapults and wires positions are 
calculated.

In order to get these data into the JSB FDM, the crude  solution could be, to 
include the yasim calculation part into JSBSim.

I feel that won't be the more elegant solution, and i am not sure that Jon 
would agree on it.  :)

Though, i am not aware, about the FG source organisation, i dare that 
question:

Won't it be possible to calculate and to give on request ( when we are close 
to a  Carrier ) these data.
I mean, the cats and wires positions ?

I guess, if we had these values it should possible to process them into JSBsim 
in order to get an achieved Carrier Landing/takeOFF simulation.
At least , easier for Jon to include that simulation into JSBSim.

I can be wrong, it could be many other better approach

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=100url=/
___
Flightgear-devel mailing list
Flightgear-devel@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/flightgear-devel