The property /fdm/jsbsim/propulsion/engine/prop-induced-velocity_fps
gives wrong answers, and can become NaN under certain conditions. When thrust is
negative and forward velocity is small we can take the square root of a negative
number. This could occur, for example, when using reverse thrusters on landing.
The value comes out much too high when alpha is near 180, such as taxing with a
tail wind.
are the accelerations (forces) as felt from the pilot's perspective. This
combines the accelerations due to change in velocity vector and gravity.
Previosly the gravity part was right, but the body accelerations were being
transformed incorrectly. The error was very subtle and basically amounted to
the fact that inverting an axis of a vector before transforming it is not
equivalent to transforming the vector and then inverting that axis.
After this fix, pilot accelerations + gyro + gps can be fed into an external
kalman filter and it will converge properly (extra confirmation that there
was a problem and this fix corrects it.)
Replace SG_GENERAL by more specific log classes in many places.
Allow "," to separate logging classes (using "|" is odd on the
command-line).
Also add new option to make logging more useful for developers.
You can use:
--log-level=debug --log-class=environment
to only get environment debug messages, or
--log-level=debug --log-class=sound,ai
to only get debug messages related to the sound or AI subsystem.
1. The atmospheric properties of FG are not yet initialized when
JSBSim is initialized.
-> patch is quite basic and there may exist smarter ways to initialize
properly the environment before the FDM.
2. The Euler angles were initialized after the velocities.
3. The glide slope and rate of climb were ignored. Fixes all FDMs (YASim,
UIUC, JSBSim, etc.)
4. Some properties were instructed to re-use their previous value while
they should not.
5. Some bugs existed in JSBSim trim code. -> This bug has already been
fixed in JSBSim but the corresponding patch has not yet been applied to FG.
coordinated with and approved by Andy.
The lattice(x,y) arguments were being "WRAP()'d" but the WRAP() function
didn't make sense. Instead it was forcing the value to zero if it was
greater than the wrap limit. This was creating large areas of constant
values in the perlin noise maps which resulted in a "constant" turbulence
vector over time -- which is just weird.
Andy couldn't see any reason why the values should be wrapped and couldn't
remember any reason why the WRAP() function was set up like it was.
Andy wanted me to make sure and mention that he was INSANE when he wrote that
code (but now he's sane ... err, mostly.)
The internal solver of YASim which computes drag and lift
coefficients now actually uses the values configured in
the XML input file for approach fuel, cruise fuel and cruise
glide angle.
Untieing needs to be done prior to the destruction of the object which
aggregated the TiedPropertyList. So the TiedPropertyLists destructor can't
untie the properties automatically (and it doesn't). So, do some manual
clean-up.
Use shared property pointers instead of path strings, adapt method
names to JSBSim style, catch all property ties, proper error handling
when tieing failed.
Extends and partially reverts commit 287cc74965
Previous fix did not consider properties outside the /fdm/jsbsim branch.
FGPropertyManager now keeps track of all its tied properties - and provides
a method to cleanly untie them again.
Use shared property pointers instead of path strings, adapt method
names to JSBSim style, catch all property ties, proper error handling
when tieing failed.
Extends and partially reverts commit 287cc74965
Previous fix did not consider properties outside the /fdm/jsbsim branch.
FGPropertyManager now keeps track of all its tied properties - and provides
a method to cleanly untie them again.
Priority scheme for tile loading/removing
Cleaner tile manager interface for AI/groundcache/...
Reduce start-up delay. Drop splash screen when inner scenery is available.
Be nice to osg loader: slow-down main loop while initial scenery is still loading.
Add the same computation of /position/altitude-agl-ft for
the magic carpet fdm as it is used in the ufo fdm. This
property is used in the environment controller to interpolate
between the individual weather-condition layers.
The track is computed between two subsequent settings of the geodetic position and represents the true track.
Also the _set_Latitude() and _set_Longitude() methods were removed. Use _set_Geodetic_Position(lat,lon) instead.
Improvements to the cloudsystem:
- A new xml format
- Texture indexing based on the position of the sprite in the cloud
mass, allowing more control over the texture set.
- Improved fog and shading
- Better sprite distribution
- A more natural distribution of clouds, so no more obvious grids.
Patches for configure.ac and Makefile.am files in FG/SG so Mac developers can build these in a unix way.
These also enables Mac developers to choose either PLIB framework or PLIB static libs.
Additionally to the original fix (problem with the Tec2b matrix initialization) I have modified the code for the "STRUCTURE" contacts in order not to generate NaNs when the z direction of the body frame is normal to the ground normal. Now there should no longer be any NaN generated by the landing gear code.
* line 343: comparison between signed and unsigned integer expressions
* line 441: 'lon', 'lat', 'slr' and 'alt' might be used uninitialized
* line 565: enumeration value 'etUnknown' not handled in switch
time' code paths. The problem may lead to skipped fdm updates at very high
frame rates. The most visible effect of that was that the aircraft
slips backwards wrt the forward moving carrier.
Remove unused stuff.
Modified Files:
configure.ac projects/VC7.1/FlightGear.vcproj
projects/VC8/FlightGearLib.vcproj src/Cockpit/cockpit.cxx
src/FDM/Makefile.am src/FDM/flight.cxx src/FDM/flight.hxx
src/FDM/SP/Balloon.cxx src/FDM/SP/BalloonSim.cpp
src/FDM/SP/BalloonSim.h src/Main/Makefile.am
src/Main/fg_init.cxx src/Main/main.cxx src/Time/Makefile.am
Removed Files:
src/Time/fg_timer.cxx src/Time/fg_timer.hxx
queries. This also fixes some issues with the carrier and the croaser
altitude values that is used when no hit is found.
Include some ifdefed out debugging code, that might be interresting.
Modified Files:
groundcache.hxx groundcache.cxx
Make leaner interfaces to the groundcache.
Remove legacy interfaces.
Update users of them.
Add new query routines for 'nearest point' and 'body with given id'.
Modified Files:
src/FDM/flight.cxx src/FDM/flight.hxx src/FDM/groundcache.cxx
src/FDM/groundcache.hxx src/FDM/JSBSim/JSBSim.cxx
src/FDM/JSBSim/JSBSim.hxx src/FDM/YASim/FGGround.cpp
src/FDM/YASim/FGGround.hpp src/FDM/YASim/Gear.cpp
src/FDM/YASim/Gear.hpp src/FDM/YASim/Ground.cpp
src/FDM/YASim/Ground.hpp src/FDM/YASim/Model.cpp
Background are problems modeling the rotax 912 engine. The idle speed
of the real engine is about half of the speed I could achieve with the
default minimum manifold pressure. While on ground I can switch off
the engine by pulling the throttle. The audible difference between the
different minimum idle speed (real vs. simulated) is extreme. With the
patch I get quite realistic sound. For the rotax engine I use
min-throttle="0.05" which is half of the former default value.
This gets rid of a lot of messy code. Although the performance is about
the same as the old code, there is the possibility of a big performance
boost if/when the polytope intersector is taught about KD trees.
* experimental clean-up / reduction on two of the FG headers:
(I'm going to await feedback on the developers list before doing more of
these, to avoiding going over files multiple times, but in principle it
seems pretty straightforward.)
* final fixes for SG_USING_STD removal
- this exposed a bizarre issue on Mac where dragging in <AGL/agl.h> in
extensions.hxx was pulling in all of Carbon to the global namespace
- very scary. As a result, I now need to explicitly include CoreFoundation
in fg_init.cxx.
- change SG_USING_STD(x) to using std::x
SimGear change. It changes all the SG_xxxx to be the 'real' includes, and gets
rid of many #ifdef SG_HAVE_STD_INCLUDES. As an added bonus, rather than
replacing 'SG_USING_NAMESPACE(std)' with 'using namespace std', I just fixed
the small number of places to use std:: explicitly. So we're no longer polluting
the global namespace with the entire contents of std, in many cases.
There is one more 'mechanical' change to come - getting rid of SG_USING_STD(X),
but I want to keep that separate from everything else. (There's another
mechnical change, replacing <math.h> with <cmath> and so on *everywhere*, but
one step at a time)
PLETE_FUNCTIONAL from SimGear and FlightGear.
As a result, SG_HAVE_STD_INCLUDES is now *always* set, so I will get the boring
fixes for that done, but separately. I'm still auditing the other things in comp
ilers.h - there's a lot that can die now BORLAND is gone.
The LOD far range on the tile entry scenegraph node was initialized to
0. This meant that any traverals of active children that happened
before the tile manager updated the node would ignore the node
altogether. Among these is the groundcache traversal which was failing
at startup even though scenery was loaded.
Also added a function to dump scene graph nodes to files; very handy
in gdb.
This fixes a race condition when teleporting somewhere outside of the
currently loaded scenery. Before, if there was no valid scenery, an
aircraft might end up at the center of the earth...
_material was uninitialized. This was causing a segfault with
as-yet-to-be-checked-in paging code; I don't know if it ever resulted
in a segfault with the old tile loader, but it certainly could have.
src/FDM/flight.cxx src/FDM/flight.hxx
src/FDM/LaRCsim/LaRCsim.cxx src/FDM/SP/ADA.cxx
src/Scenery/scenery.cxx src/Scenery/scenery.hxx:
Remove obviously unused variables from FGInterface, make use of
SGMath functions. No longer use plib math functions in FGInterface.
"minor update for the rotor FDM. It results in a more realistic
calculation of the phase shift of rotor and therefor in a little bit
more realistic flight behavior.
(Additionally you can modify the initial position of the rotor and some
(not finished) modifications for the jet ranger rotor)."
"""
Fix Y2K bug triggering string overflow
sim_control_.date_string is a char[7], so it can contain "yymmdd" and
the terminating '\0'. However, nowtime->tm_year is 107 for the year 2007,
so you'll end up with a 7 digit number and the string written to
sim_control_.date_string is longer than sim_control_.date_string is.
Ouch!
"""
mf: ... and sim_control_.date_string isn't even used.
"""
- ground properties (e.g. feel bumpiness and the reduced friction of
grass or go swimming with the beaver)
- initial load for yasim gears (to get rid of the jitter the beaver has
on ground)
- glider/winch/aerotow (do winch start with YASim glider or do aerotow
over the net) I will place a how-to on the wiki soon, here very short:
use the sgs233y (or the bocian if you have AJ (up ot now) non-GPL
bocian)
winch start: Ctrl-w for placing the winch, hold w to winch, press
Shift-w to release the tow
aerotow: Place the glider within 60m to a MP-aircraft, press
Ctrl-t to tow to this aircraft. If the MP-aircraft is the
J3 and the patch is installed on both sides, the J3 feels the
forces, too. The J3-pilot has to taxi very slow up to the
moment, the glider starts moving. Increase the throttle gently.
Don't lift the J3 early, wait for the glider being lifted,
lift gently.
"""
src/FDM/groundcache.cxx src/FDM/groundcache.hxx: Store the material
that was used to get the croase agl level and return that material
in case we need to make use of that croase value.
utils/Modeller/Makefile.am src/FDM/YASim/Makefile.am:
Remove -lssg from the linker lines.
Do no longer build threedconvert. A very similar functionality
is available with osgvconv. But leave threedconvert in place
if somebody will need that ...
I found a small conspicuity in YASim. The destructor of the fdm was
never called, therefore a modification of the heli fdm (not in cvs) did
not work after reset (I tie some properties and untie them in the
destructor, but the destructor was not called and the tieing failed
after reset. I don't know if any other parts of YASim need their
destructors, at least it wastes memory.
Another small fix I have made to the turbulence.cpp. The code needed,
that (a-floor(a)) is >=0 and <1. This is analytical correct, but
numerical only for "small" values. In normal fg-operation a in this
function is always small, but with unrealistic parameters in the
aircraft config file it is not and then fg crashes (instead a crash of
the aircraft or cataputling it far away).
More realistic calculation of vortices at the blades and therefore
real airfoil parameters can be used now (not to be mixed up with the
vortex ring state which is still not simulated), ground effect is now
continuous e. g. at buildings, calculating of the rotor in more than 4
directions, better documentation of the airfoil parameters.
values that were angles between the aircraft's orientation and the
global velocity vector, not the airflow velocity. So the HUD velocity
vector was wrong when the wind was non-zero. Fix that.
generates a data file of aerodynamic lift and drag (and L/D) against
AoA at a specified speed and altitude through a full circle. Wrote it
to track down the YF-23 superthrust issue, but it wasn't any help.
All the forces look fine.
state. The only really obvious problem was a giant negative engine
RPM, which happened because of a lack of clamping in the engine code
combined with the YF-23's ability to actually reach speeds near the
engines _vMax value. It's not clear to me that this will fix the
superthrust issue at high AoA's, but it's an obvious bug nonetheless.
+ The wing compilation step was accidentally omitting regions that lie
between the tips and the first/last control object. That's a real
problem for wings that contain no controls, and a significant issue
for those that contain only a few. I'm stunned that this went
undetected for so long.
+ The Surface::flapLift() function was oddly returning 1.0 Newtons as
a minimum, instead of zero.
calculations. We run the FDM at 120hz and compute how many loops can fit into each FG loop.
Floating point rounding could lead to a situation where we could end up running
1, 3, 1, 3, 1, 3... loops of the FDM when in fact we want to run 2, 2, 2, 2, 2...
If we artificially inflate ml above by a tiny amount to get the
closest integer, then subtract the integer from the original
slightly smaller value, we can get a negative remainder.
Logically this should never happen, and we definitely don't want
to carry a negative remainder over to the next iteration, so
never let the remainder go below zero.
src/AIModel/AIAircraft.cxx src/ATC/AILocalTraffic.cxx
src/FDM/flight.cxx src/FDM/flight.hxx src/FDM/groundcache.cxx
src/FDM/groundcache.hxx src/Main/fg_init.cxx src/Main/main.cxx
src/Scenery/hitlist.cxx src/Scenery/hitlist.hxx
src/Scenery/scenery.cxx src/Scenery/scenery.hxx
Make use of the attached SGMaterial reference userdata on scenegraph
leafs. Make the SGMaterial pointer available to the ground query
routines.
SGPropertyNode to guarded ones. This is also done for JSBSim/JSBSim.hxx,
for which JSB had given explicit permission a while ago. I postponed that
back then, but now is the time.
I had inadvertently terminated a data line when reaching a tab character after
initial data was supplied. I tested the lightning file and it now appears to
read in correctly.
bunch of memory leaks that had accumulated over the years. FlightGear
doesn't currently bother to destroy and recreate a YASim context, but
at least it can do so now without worry.
groundcache addition -- the ground callback doesn't do anything at
solution time, so the ground plane was unset. Valgrind was whining
about this; it's not clear that it was actually causing a problem.
and in the calculation of the launchbar angle (by Vivian).
It also calculates the holdback angle, and sets a Boolean value which
can be used to initiate the release of the catapult strop submodel at
the appropriate moment (new code by Vivian).
control to piston engines that allows external scripts to control the
turbo/supercharger boost programatically by setting this axis to
values in the range [0:1]. It also adds a "turbo-lag" attribute (a
time in seconds) to engines implementing turbocharger spooling delays.
This isn't terribly well tested, but doesn't seem to have broken
anything.
propeller pitch stops for constant speed propellers. The default
values are the same as the previous hard-coded values. The new
attributes, "fine-stop" and "coarse-stop", are documented in the base
package, Docs/README.yasim.
This patch makes use of the vectors now available in simgear with that past
patch. And using that it simplyfies the carrier code somehow.
- Small additional factory's to the quaternion code are done in the simgear
part. Also more explicit unit names in the factory functions.
- The flightgear part makes use of them and simplyfies some computations
especially in the carrier code.
- The data part fixes the coordinate frames I used for the park positions in
the carrier to match the usual ones. I believed that I had done so, but it
was definitly different. Also there are more parking positions avaliable now.
Jon Stockill wrote:
> I've just discovered that when using the null fdm I'm not getting
> updates to /position/ground-elev-m any more. So I can't actually
> retrieve the terrain elevation. Is there somewhere else in the property
> tree I could read this from?
The attached patch fixes this problem.
Erik Hofman:
This patch contains an update to net_ctrls.hxx that adds an extra 100 bytes
(or an equivalent of 25 (u)int32_t types) of reserved space. This could be
used to make the protocol forward and backward compatibel within a certain
scope. Be sure to read the instructions at the begining of the header file
when addinf new variables.
remove a hack and do it properly: if the requested elevation is for some
reason below the surface and the intersection test fails (as it appears
to be the case in EGLL), try again from 10000m ASL
mf: typos
are sharp, as intended. These were are never seen in practice; I
found the problem while looking at 360 degree lift curve graphs
looking for discontinuities.
"jitter" when the aircraft was stopped. This is a fundamental
characteristic of the gear model, and can't be fixed without major
surgery (and not a small amount of blinding insight). But we can at
least clamp it so the value can't change unless the wheel is moving
with a nontrivial velocity (5cm/sec in this case).
there was the situation where four directories contained jst two files,
of which three directories were aircraft related, and one directory contained
test code from Curt that might be better of in SimGear anyhow.
This is just a patch to move a bunch of files to new locations. In case of
local changes to any of them you can do the following:
move replay.[ch]xx from src/Replay to src/Aircraft
move control.[ch]xx from src/Control to src/Aircraft
move ssgEntityArray.[ch]xx from src/Objects to simgear/screen
In addition it has been decided only to use .[ch]xx files in all directories
unless it's contained within an FDM specific directory, in which case the
author is free to do whatever (s)he wants.
In this repspect the following files have been renamed in src/Multiplayer:
tiny_xdr.[ch]pp has become tiny_xdr.[ch]xx
multiplaymgr.[ch]pp has become multiplaymgr.[ch]xx
CygWin/gcc-3.4.4 updates.
I replaced my cygwin compiler with 3.4.4, did a make clean of plib, simgear,
and flightgear, then did a make install of all three. With the included changes,
everything builds fine, and runs fine.
Attached is a patch to add oil temperature to the YASim piston engine
model. This brings to life one of the pa28-161's otherwise 'dead'
guages. It's a pretty simple 'model' based on temperatures and warmup
times I've observed in the labs on auto engines and run through my
dodgy-memory filter. It does the job of populating the guage with
something plausible though.
Using new gcc 4.0 I have some serios warnings about uninitialized
variables, that are used. I created a patch, but I have no idea if it
is possible to do it my way. Can you check this out please?
Erik: I've modified the patch slightly based on the contents of an older
version of hitlist.cxx. I think this is correct now.
it for the B-29). The gear model itself has supported this always,
but there was no interface from the XML file. Should be backwards
compatible. I don't think I broke anything...
I stumbled across two memory errors with two wrong const references to
std::string.
As I fixed that, I also moved aircraft_dir which is only used from UIUC into
UIUC. With that uiuc_aircraftdir.h is empty and can be removed.
I believe I have found the agl hud problems as well as the 'hole' in the
carrier's deck. I spent half the day to reproduce that problem, it did not
occure when you start on the carrier not does it occure with JSBSim and my
really often used testaircraft. So I really need to improove my helicopter
flying qualities.
I was under the impression that *all* FDM's call
FGInterface::updateGeo*Position(..)
so set the new position in the FDM interface. Therefore I had added at the
some code that updates the scenery elevation below the aircraft to *those*
functions.
Ok, not all FDM's do so :/
The attached patch factors out a function computing the scenery altitude at
the current FDM's position. This function is also used in those FDM's which
need to update this value themselves.
Also this patch restores the nearplane setting and uses the current views
altitude instead of the current aircrafts. I think that this should further
be changed to the eypoint's agl in the future.
The agl is again ok in YASim's hud.
