Re: [Flightgear-devel] YASIM Options
John Wojnaroski writes: Does fgGetdouble(/controls/flaps) return the value for the position of the flaps or the value the flaps are commanded to? Same for gear and slats. Is the code such that all setters work as directed and surfaces move to the commanded postion so that actual=command? It's the control position, not (necessarily) the flap position. Also, does the gear still exhibit extention/retraction delays. Is there a fgGetDouble(/controls/gear[n]-position') or something like that which returns a value from 0 to 1? We do need to add properties, but not under /controls. Perhaps an /fdm subtree would be useful, i.e. /fdm/deflections/flaps[0] etc. All the best, David -- David Megginson [EMAIL PROTECTED] ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
John Wojnaroski wrote: Also, does the gear still exhibit extention/retraction delays. Is there a fgGetDouble(/controls/gear[n]-position') or something like that which returns a value from 0 to 1? Aerodynamically, yes. The gear is interpolated from all to none over the retract-time specified. But you can't see that in the properties; all you get is the control position. David is right, we need to decide on a set of output properties for the actual surface positions. Note that 747 has a FLAP0 and FLAP1. No asymetric flap conditions - one control for both? Not quite. The term flap in the YASim configuration files refers to any moving-flap control surface. The two on the wings are the landing flaps and ailerons. The wing definition is mirrored by default, so there's no need to specify both flaps (or both ailerons). So the control mapping is from /controls/flaps to FLAP0, and from /controls/ailerons to FLAP1. The aileron mapping has a split=true argument to get the sense right. Note that you can have multiple control mappings for any given surface. This is there to support things like the flaperons on the F-18 or the V-tail of the early Bonanzas. Oh, and apropos of the 747, I tried it again last night and reproduced the power bug that you and Jim Wilson reported. I haven't a clue, although I know it used to work (I distinctly remember cruising at 36000 ft.). I must have broken something, probably in the engine model; I'll take a look. Andy ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
Aerodynamically, yes. The gear is interpolated from all to none over the retract-time specified. But you can't see that in the properties; all you get is the control position. David is right, we need to decide on a set of output properties for the actual surface positions. Yes. kept scratching my head why I could not find the output positions. With the earlier gear version the EICAS display showed a barber-pole pattern while the gear was in transit and could report on all three gear positions. looks like that was lost with the change to properties when the class FGGear was removed from FGInterface. From a distributed/network view point, it would be nice to have a set of control parameters variables that are received by fgfs, possibly mapped or transformed to aero surface actuators(actor_0, actor_1,...,actor_n), then some FCS modeling that results in movement of a corresponding aero surface (flap_0/aero_0, flap_1/aero_1) whose value could be easily accesses and output to the network for displays, autopilots, whatever. Currently using the network stuff in native_ctrls.cxx for input and opengc.cxx for output. If I knew more about how the properties work ... Oh, what the heck, I'll give it a shot...If not 0.7.9 then maybe the next. Any comments, guidance, suggestions are welcomed. Oh, and apropos of the 747, I tried it again last night and reproduced the power bug that you and Jim Wilson reported. I haven't a clue, although I know it used to work (I distinctly remember cruising at 36000 ft.). I must have broken something, probably in the engine model; I'll take a look. Here is some engine data and flight conditions derived from another 747 sim. These are pretty close to real numbers At 80 kts, (TOGA setting power) EPR 1.441.441.441.44 N1 103.4102.3103.4104.1 EGT 631 632631629 N2 94 939494 F/F16.1 16.116.116.1 Oil press110 110112111 Oil temp 49 48 49 50 At 2000 ft 230ts 2000fpm climb rate EPR1.451.451.451.45 N1103.9102.8103.9104.9 EGT637639637635 N294949494 F/F16.116.116.116.1 Ot112110112113 Ot92919293 At 5000 ft 270 kts 2000 fpm up 1.391.391.391.39 101.6100.6101.6102.6 636638636634 92929292 13.813.813.813.9 At 10,000 267 kts 3000 fpm up 1.401.401.401.40 101/6100.6101.6102.6 635637635633 92929292 At 15,000 310 kts 1.411.411.411.41 102.5101.5102.5103.5 93939393 11.111.111.111.1 112110112113 139139139140 At 20,000 310 kts 2000 fpm climb 1.431.431.431.43 102.4101.5102.4103.4 636638636634 93939393 11.211.211.211.2 At 25,000 310 kts 2000 fpm up 1.431.431.431.43 102.5101.5102,5103.5 636637636634 93939393 112110112100 141140141142 At 29,000 1.301.301.301.30 618619617616 88888888 6.46.56.56.5 Initial cruiise At 33,000 310 kts (.872mach) EPR1.431.431.431.43 n1102.1101.1102.1103.1 EGT633635633632 N293939393 F/F 8.18.18.18.1 OIL P111110111 112 OIL T140137138138 Data for 15,000 ft, 320 kts, level flight: EPR1.171.171.171.17 N1 91.091.091.092.0 EGT559559559551 N283838383 FF4.84.8 4.8 4.8 Oilp101101100100 Olit 71 71 70 71 Idle descent from 15k to 10k 250 kts EPR all 0.98 N122.722.722.523.1 EGT318318316319 N264646465 FF1.11.11.11.1 Level 10,000 250 kts EPR all 1.11 N186.786.785.888.0 EGT513512515520 N1 all 79 FF all 4.5 oil press all 94 oil temp all 77 got these from jim at kingmont.com. Regards John W. ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
John Wojnaroski wrote: both 747 and f15 seem to be underpowered. or possibly too much drag? Can't hold a vertical climb in the f15 and can only get to mid altitudes in the teens with 747 This is the second time this has been reported, but I can't reproduce it. Your note later on, however, looks like a good clue: does each each engine have a throttleor is it a single command for all four(two)? They are separate properties -- the left engine(s) use /controls/throttle[0], while the right are controlled by /controls/throttle[1]. This is handled in the aircraft XML file. I didn't define four separate controls for the 747 because I was lazy; making that work would require changes to the default control mappings. If your throttle is only jiggling the first property, then that's the bug right there -- you're only getting half the thrust. engine egt is given in degrees centigrade and fuel-flow for turbines is usually given as #/hr (1 gal ~ 6.5 pounds) The current egt property hands you fahrenheit. Fuel flow is in gallons per hour. Especially with the fuel, I'd agree with your choice of units; but nonetheless that's what the standard currently says. Maybe we should go through and audit the FDM outputs for a sane set of baseline units. Engine data is a little screwy. running jbsim for the c310 no data comes across and for yasim-747 the zeroeth values are missing. Not sure i've got this properties thing all figured out yet. Missing? Weird. There were some changes here recently that might be causing this. David was kind enough to give me a heads up about the changes to the YASim code, but I ignored it. :) I'll take a look. Andy ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
John Wojnaroski wrote: New question. controls for teh gear and flaps? will the existinig bindings for the keyboard work? Are the gear and flap values now properties? The gear is controlled by /controls/gear-down, a boolean. The flaps are in /controls/flaps, a floating point number from 0 (no deflection) to 1. Also, the 747 has slats, which it looks for in /controls/slats, with the same convention. There's no default keyboard mapping for this. Andy ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
Andy wrote The gear is controlled by /controls/gear-down, a boolean. The flaps are in /controls/flaps, a floating point number from 0 (no deflection) to 1. Also, the 747 has slats, which it looks for in /controls/slats, with the same convention. There's no default keyboard mapping for this. A question on semantics? Does fgGetdouble(/controls/flaps) return the value for the position of the flaps or the value the flaps are commanded to? Same for gear and slats. Is the code such that all setters work as directed and surfaces move to the commanded postion so that actual=command? Also, does the gear still exhibit extention/retraction delays. Is there a fgGetDouble(/controls/gear[n]-position') or something like that which returns a value from 0 to 1? Note that 747 has a FLAP0 and FLAP1. No asymetric flap conditions - one control for both? Regards John W. ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
Andy wrote Just need to get the turbine data across the link (Assuming that YASIM is generating N1, N2, EGT, EPR, oil pressure, fuel flow, etc) Sure thing: /engines/engine[n]/n1 /engines/engine[n]/n2 /engines/engine[n]/epr /engines/engine[n]/egt-degf /engines/engine[n]/fuel-flow-gph couple of comments and questions: both 747 and f15 seem to be underpowered. or possibly too much drag? Can't hold a vertical climb in the f15 and can only get to mid altitudes in the teens with 747 for f15 should be able to do an idle power loop @ 10K feet with an entry airspeed of around 250 to 300kts engine egt is given in degrees centigrade and fuel-flow for turbines is usually given as #/hr (1 gal ~ 6.5 pounds) Engine data is a little screwy. running jbsim for the c310 no data comes across and for yasim-747 the zeroeth values are missing. Not sure i've got this properties thing all figured out yet. In opengc.cxx data-n1_turbine[0] = fgGetDouble(/engines/engine[0]/n1); data-n1_turbine[1] = fgGetDouble(/engines/engine[1]/n1); // and so forth packs the data into the UDP packet Looks okay? does each each engine have a throttleor is it a single command for all four(two)? regards John W. ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
Engine data is a little screwy. running jbsim for the c310 no data comes across and for yasim-747 the zeroeth values are missing. Not sure i've got this properties thing all figured out yet. In opengc.cxx data-n1_turbine[0] = fgGetDouble(/engines/engine[0]/n1); data-n1_turbine[1] = fgGetDouble(/engines/engine[1]/n1); // and so forth packs the data into the UDP packet Looks okay? does each each engine have a throttleor is it a single command for all four(two)? regards John W. ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
Engine data is a little screwy. running jbsim for the c310 no data comes across and for yasim-747 the zeroeth values are missing. Not sure i've got this properties thing all figured out yet. In opengc.cxx data-n1_turbine[0] = fgGetDouble(/engines/engine[0]/n1); data-n1_turbine[1] = fgGetDouble(/engines/engine[1]/n1); // and so forth packs the data into the UDP packet Looks okay? Found the problem, a couple of the arrays were misaligned in the respective class definitions. New question. controls for teh gear and flaps? will the existinig bindings for the keyboard work? Are the gear and flap values now properties? Regards John W.g ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
[Flightgear-devel] YASIM Options
Hi, Believe there was a discussion while back regards YASIM options, but can't find it. Could someone tell me command line options for running YASIM with the various models? Thanks John W.
Re: [Flightgear-devel] YASIM Options
John Wojnaroski writes: Hi, Believe there was a discussion while back regards YASIM options, but can't find it. Could someone tell me command line options for running YASIM with the various models? With the cvs version you should just have to look in $(FG_ROOT)/Aircraft and find all the *-set.xml files. There should be several yasim entries so if you want to try the YASim DC-3, you just need to run fgfs --aircraft=dc3-yasim Curt. -- Curtis Olson Intelligent Vehicles Lab FlightGear Project Twin Cities[EMAIL PROTECTED] [EMAIL PROTECTED] Minnesota http://www.menet.umn.edu/~curt http://www.flightgear.org ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
John Wojnaroski wrote: Believe there was a discussion while back regards YASIM options, but can't find it. Could someone tell me command line options for running YASIM with the various models? If you're just running it, then the aircraft files already take care of everything for you. Just use --aircraft=xxx-yasim (where xxx can currently be c172, c310, dc3, a4, harrier, or 747). The only command line argument that will affect the FDM as such is overriding the /sim/fuel-fraction property. The jets, especially, have different performance with different fuel loads. Just use: --prop:/sim/fuel-fraction=0.2 (for example) to get a reasonable approach configuration. With the jets, you'll also want the HUD turned on as there aren't any panels yet. I use: --enable-hud and --disable-panel for these guys. There's also a complication with the Harrier. You'll need to map a joystick axis to the /controls/thrust-vector[0] property in order to work the thrust vectoring. A keyboard interface would be possible too, but due to the lack of a panel there's no feedback to the user about what the setting is currently. I use one of the rotary dials on my Saitek X45 (OT note: a *GREAT* joystick, if anyone is interested in recommendations) and it works great. I've been playing/practicing with the Harrier a lot recently. I really should write up a training guide or somesuch, for folks just getting into it. The learning curve on the VTOL stuff is nasty and steep, kind of like being a real life test pilot on the things. Loads of fun. I can *almost* reliably land vertically now -- but hovering still eludes me. Once I move away from the location I picked to land on, I have to fly off and re-do the whole approach. Oh, and Gene: I've got an F-15C for you (attached) but I'm not entirely satified with it. What's happened is that the parasite drag has to be pushed so low by the solver in order to match the mach 2.5 cruise number that the induced drag (that is, the backwards component of the lift at non-zero AoA) ends up dominating. The aircraft bleeds speed *fast* in a turn, much faster than the A-4, which has a broadly similar wing configuration and loading. I'll need to put in supersonic drag handling before this works really well. But it takes off, lands, and accelerates more or less like the real thing. Andy -- Andrew J. RossNextBus Information Systems Senior Software Engineer Emeryville, CA [EMAIL PROTECTED] http://www.nextbus.com Men go crazy in conflagrations. They only get better one by one. - Sting (misquoted) ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
John Wojnaroski wrote: Actually using a set of glass displays I've developed that match the 747 flight deck. Runs on a seperate machine with a LAN interface and has a full set of EICAS (Engine Instruments Crew Alerting System) and Navigtion displays. Oh yeah. Duh. I knew that. :) I *will* try that someday, but I'm lacking the required second machine at the moment. Just need to get the turbine data across the link (Assuming that YASIM is generating N1, N2, EGT, EPR, oil pressure, fuel flow, etc) Sure thing: /engines/engine[n]/n1 /engines/engine[n]/n2 /engines/engine[n]/epr /engines/engine[n]/egt-degf /engines/engine[n]/fuel-flow-gph No oil pressure though, because I haven't seen any data on what it should look like. I suspect it'll just scale linearly (with a zero-offset) with N1 (presuming that's the turbine stage that runs the oil pump) for a given engine. If you have cruise data for oil pressure, I'd love to see it. Also, recognize that these numbers have had only the most cursory testing; I make no promises. The actual numbers that the current jet model is turning out are those for a 707 turbojet at the same fractional power. The numbers themselves can be tuned to match any given engine, but no such work has been done yet. Specifically, you'll see EPR numbers that are too high for the turbofans the 747 is using. The fuel flow is based on a TSFC specified in the jet tag in the aircraft XML. I don't know if I got that right, either. Although this one is kind of academic as YASim doesn't actually consume fuel yet. :) It also gets a little goofy at supersonic speeds. Due to ram air compression, the power goes up with speed faster than a real engine should -- the F15 at mach 2.5 is showing something like 128% N1. Real engines have complicated inlet losses at high mach that aren't modelled. Not a problem with the 747, but just something you might notice. Andy -- Andrew J. RossNextBus Information Systems Senior Software Engineer Emeryville, CA [EMAIL PROTECTED] http://www.nextbus.com Men go crazy in conflagrations. They only get better one by one. - Sting (misquoted) ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
re: [Flightgear-devel] YASIM Options
John Wojnaroski writes: Could someone tell me command line options for running YASIM with the various models? fgfs --aircraft=c172-yasim fgfs --aircraft=c310-yasim fgfs --aircraft=dc3-yasim etc. All the best, David -- David Megginson [EMAIL PROTECTED] ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
Re: [Flightgear-devel] YASIM Options
Andrew wrote: Oh yeah. Duh. I knew that. :) I *will* try that someday, but I'm lacking the required second machine at the moment. Just need to get the turbine data across the link (Assuming that YASIM is generating N1, N2, EGT, EPR, oil pressure, fuel flow, etc) Sure thing: /engines/engine[n]/n1 /engines/engine[n]/n2 /engines/engine[n]/epr /engines/engine[n]/egt-degf /engines/engine[n]/fuel-flow-gph Double Duh!! After downloading and compiling the latest CVS, (my last update was mid -dec) I added my latest changes to the interface and it naturally bombed, big time. When I realized that the FGEngInterface class was gone my first reaction was OH NO!!! I should have looked at the opengc.cxx source first before replacing it. :-O Whoever made the changes in opengc.cxx to properties, thank you. I've duplicated a lot of the navigation code on the opengc side which reduces the interface immensely and makes building the FMC a lot easier. for example, the FMC does such things as auto-tuning to select VOR stations in range to update current position against the flight plan, displays routes, waypoints, airports, and such. There are 12 to 13 different Nav displays including weather radar, lots of eye-candy to build! zero-offset) with N1 (presuming that's the turbine stage that runs the oil pump) for a given engine. If you have cruise data for oil pressure, I'd love to see it. If you want a good source for engine data from taxi to cruise, touch base with [EMAIL PROTECTED] Thanks again John w. ___ Flightgear-devel mailing list [EMAIL PROTECTED] http://mail.flightgear.org/mailman/listinfo/flightgear-devel
