Re: [Flightgear-devel] Yasim static friction?
Hi Andy, Thanks for that! So just to clarify -- this is a bug in Yasim code (or more like a missing feature) and I'm welcome to fix it? :) Cheers, Vik On 07/05/2012 09:34 PM, Andy Ross wrote: > (Happened to be browsing in time to see a question) > > On 07/05/2012 06:21 AM, Viktor Radnai wrote: >> I don't see any obvious properties to set to take the engine's >> resistance to turning over, or the friction of the wheels into account >> to stop these unrealistic things from happening. How should I go about >> fixing them? > > That sounds right to me. Aircraft parked in gentle winds weren't really > part of the original test regime. :) > > For the gear thing, see Gear.cpp:450 or so, and look at clamping the > static friction coefficient to some minimum value (probably tunable). > > For the engine, you can likewise add some fixed negative torque value > near PistonEngine.cpp:214 to model internal resistance (currently the > code only models output power). > > Andy > > -- > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > ___ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/flightgear-devel > -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery licence for 2.8 and later
Curtis Olson wrote: > [...] or scenery GPL? :-) Who cares about Scenery >;-) Martin. -- Unix _IS_ user friendly - it's just selective about who its friends are ! -- -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Yasim static friction?
(Happened to be browsing in time to see a question) On 07/05/2012 06:21 AM, Viktor Radnai wrote: > I don't see any obvious properties to set to take the engine's > resistance to turning over, or the friction of the wheels into account > to stop these unrealistic things from happening. How should I go about > fixing them? That sounds right to me. Aircraft parked in gentle winds weren't really part of the original test regime. :) For the gear thing, see Gear.cpp:450 or so, and look at clamping the static friction coefficient to some minimum value (probably tunable). For the engine, you can likewise add some fixed negative torque value near PistonEngine.cpp:214 to model internal resistance (currently the code only models output power). Andy -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery licence for 2.8 and later
On Thu, Jul 5, 2012 at 1:50 PM, Curtis Olson wrote: > On Thu, Jul 5, 2012 at 1:42 PM, Martin Spott wrote: > >> Hi Curt, >> >> Curtis Olson wrote: >> >> > We !!!STRONGLY!!! encourage authors to use the GPL [...] >> >> except from SimGear, which is supposed to be LGPL, correct ? >> > > Yes. :-) > Perhaps RMS needs to craft a DGPL (data GPL) license or CGPL (content GPL) or aircraft GPL or scenery GPL? :-) Curt. -- Curtis Olson: http://www.atiak.com - http://aem.umn.edu/~uav/ http://www.flightgear.org - http://gallinazo.flightgear.org -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery licence for 2.8 and later
On Thu, Jul 5, 2012 at 1:42 PM, Martin Spott wrote: > Hi Curt, > > Curtis Olson wrote: > > > We !!!STRONGLY!!! encourage authors to use the GPL [...] > > except from SimGear, which is supposed to be LGPL, correct ? > Yes. :-) Curt. -- Curtis Olson: http://www.atiak.com - http://aem.umn.edu/~uav/ http://www.flightgear.org - http://gallinazo.flightgear.org -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery licence for 2.8 and later
Hi Curt, Curtis Olson wrote: > We !!!STRONGLY!!! encourage authors to use the GPL [...] except from SimGear, which is supposed to be LGPL, correct ? Cheers, Martin. -- Unix _IS_ user friendly - it's just selective about who its friends are ! -- -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery licence for 2.8 and later
On Thu, Jul 5, 2012 at 10:36 AM, Stefan Seifert wrote: > On Thursday 05 July 2012 07:50:20 Michael wrote: > > > Everything on GPL only means: > > - less scenery and airplanes included ( wasn't there recently some > > photoscenery rejected because of the GPL?) > > There are already 565 airplanes to choose from in git (all licensed GPL). > More > than enough for me, if you ask. > > > - authors lose copyrights > > You obviously don't know anything about copyright law. > > > - only to find their work rebranded and sold for ex. as flightprosim etc. > > So instead, you want to have countless unusable models because their > authors > lost interest and they are no more compatible with the current FlightGear > version and nobody being able to fix this because the license doens't > permit? > > How exactly would this be better than having 565 airplanes already with > more > coming all the time? > > > Having only the code on GPL and everything else as freeware...seems less > > narrow minded to me. > > All advanced airplane models contain code (Nasal). So you're arguing for > using > GPL for models as well. Ok. We !!!STRONGLY!!! encourage authors to use the GPL so that we can incorporate their work into the overall project and distribute the work from the flightgear.org web site. We believe this gives an author's work the maximum exposure and benefits the most users. (And this isn't so much due to the intrinsic nature of the GPL, but because of the consistency of everything licensed the same way and being inter-compatible from a copying and redistribution perspective.) The content authors also get a big benefit because they can incorporate or copy any other GPL components (cockpit instruments, effects, nasal code, textures/graphics, etc.) into their own work without having to worry about violating other people's license terms. We believe and embrace the open-source development model as a good way to bring the most value to the most people. I think the reality is that if content author's are 100% honest, we'd find that a lot of the people here that are arguing for a more restrictive/protective license probably haven't created a full 100% of the content they are concerned about restricting/protecting. The beautiful (and sometimes painful) truth of the GPL is that it tends to force everyone to extend the same rights and privileges they received to everyone else down stream. This is freedom. We can't always prevent mean/evil people from doing unethical or immoral things. But we can try really hard to protect our own freedom to do positive and constructive things and not let the mean/evil people take that away from us -- in order to have "freedom", we have to accept a certain degree of "evil" -- "ye cannot change the laws of physics." :-) But after having said all this, don't forget that an author's "original" work is their own to do with as they please. They can pick which ever license they want. They can distribute their work to different destinations under different licenses. The GPL only applies if you have included other GPL work into your own content and only if you then wish to distribute (or give/sell copies) of your work to others. The GPL is unconcerned with what you do for your own private use. Disclaimer #1: I have not had my lawyers review the content of this email for correctness, exactness, and clarity of my interpretation of the GPL. Disclaimer #2: I do not have any lawyers anyway. Curt. -- Curtis Olson: http://www.atiak.com - http://aem.umn.edu/~uav/ http://www.flightgear.org - http://gallinazo.flightgear.org -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery licence for 2.8 and later
On Thursday 05 July 2012 07:50:20 Michael wrote: > Everything on GPL only means: > - less scenery and airplanes included ( wasn't there recently some > photoscenery rejected because of the GPL?) There are already 565 airplanes to choose from in git (all licensed GPL). More than enough for me, if you ask. > - authors lose copyrights You obviously don't know anything about copyright law. > - only to find their work rebranded and sold for ex. as flightprosim etc. So instead, you want to have countless unusable models because their authors lost interest and they are no more compatible with the current FlightGear version and nobody being able to fix this because the license doens't permit? How exactly would this be better than having 565 airplanes already with more coming all the time? > Having only the code on GPL and everything else as freeware...seems less > narrow minded to me. All advanced airplane models contain code (Nasal). So you're arguing for using GPL for models as well. Ok. Stefan -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Yasim static friction?
The plane gets pushed either forward or backwards by the wind, depending on the wind direction. The prop seems to only get turned in the direction of normal rotation, even in a tailwind, which seems wrong to me. But really the main issue for me is that this amount of wind should not move the aircraft or the prop. On 07/05/2012 04:14 PM, Hyde Yamakawa wrote: > Does this happen only left wind, right? Or happens on right wind too? > > Hyde > > (2012年07月05日 10:02), Viktor Radnai wrote: >> Technically, you also have the compression of the wheels -- when the >> wheel turns, part of the tire in the front gets compressed while the >> back gets uncompressed. This is also a friction loss. Plus there is some >> friction between the rubber and the road. >> >> But my point is that the amount of friction is wrong. The plane should >> not start rolling with a 3 knot wind, that's nonsense. >> >> Static friction is greater than dynamic friction. If you stop your car >> on moderately flat terrain with no brakes, it will not start to roll >> easily, not even if it's windy. If the terrain is flat, it will stay >> put. If the slope is greater, it might start to roll very slowly with >> the bearings turning in "stick/slip" mode and then finally it will just >> roll and accelerate. So the plane should stay put until there's a 20-30 >> knot wind blowing against it. Probably more on grass. On grass with the >> real plane you might need half throttle or more to get it moving. The >> funny thing is that this part seems to be modelled correctly in >> Flightgear, so no idea what's wrong with the effect of the wind :) >> >> Same goes for the prop, the resistance the shut down engine offers is >> too small and so it's turned over way too easily. Turning the prop of >> the Falke at about 2/3 of its span requires about the same amount of >> force as lifting an object that weights 1-2 kg. This is a rough guess >> and the actual force varies during the compression cycle but you get the >> idea. >> >> For the wheels, I can try to make sure that the brakes are always >> slightly set, but what do I do for the prop? >> >> Cheers, >> Vik >> >> On 07/05/2012 03:30 PM, Emilian Huminiuc wrote: >>> On Thursday 05 July 2012 15:21:24 Viktor Radnai wrote: 1. When the aircraft is parked with no parking brake, it will usually start to roll slowly backwards -- pushed by the wind and maybe the runway slope. If I start the engine on idle, the thrust generated by the idle prop might stop this roll. On tarmac, even a 3 knot wind is enough to start pushing the plane back. On grass more is needed -- maybe 20 knots? >>> Hi, >>> >>> In that case, even in real life, there's no other friction at play than the >>> friction inside the wheel bearings, friction which is very low, almost >>> ignorable. >>> >>> Regards, >>> Emilian >>> >>> -- >>> Live Security Virtual Conference >>> Exclusive live event will cover all the ways today's security and >>> threat landscape has changed and how IT managers can respond. Discussions >>> will include endpoint security, mobile security and the latest in malware >>> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ >>> ___ >>> Flightgear-devel mailing list >>> Flightgear-devel@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/flightgear-devel >>> >> -- >> Live Security Virtual Conference >> Exclusive live event will cover all the ways today's security and >> threat landscape has changed and how IT managers can respond. Discussions >> will include endpoint security, mobile security and the latest in malware >> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ >> ___ >> Flightgear-devel mailing list >> Flightgear-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/flightgear-devel > -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Yasim static friction?
You mean when the wind is blowing from the front-left of the plane? Cheers, Vik On 07/05/2012 04:14 PM, Hyde Yamakawa wrote: > Does this happen only left wind, right? Or happens on right wind too? > > Hyde > > (2012年07月05日 10:02), Viktor Radnai wrote: >> Technically, you also have the compression of the wheels -- when the >> wheel turns, part of the tire in the front gets compressed while the >> back gets uncompressed. This is also a friction loss. Plus there is some >> friction between the rubber and the road. >> >> But my point is that the amount of friction is wrong. The plane should >> not start rolling with a 3 knot wind, that's nonsense. >> >> Static friction is greater than dynamic friction. If you stop your car >> on moderately flat terrain with no brakes, it will not start to roll >> easily, not even if it's windy. If the terrain is flat, it will stay >> put. If the slope is greater, it might start to roll very slowly with >> the bearings turning in "stick/slip" mode and then finally it will just >> roll and accelerate. So the plane should stay put until there's a 20-30 >> knot wind blowing against it. Probably more on grass. On grass with the >> real plane you might need half throttle or more to get it moving. The >> funny thing is that this part seems to be modelled correctly in >> Flightgear, so no idea what's wrong with the effect of the wind :) >> >> Same goes for the prop, the resistance the shut down engine offers is >> too small and so it's turned over way too easily. Turning the prop of >> the Falke at about 2/3 of its span requires about the same amount of >> force as lifting an object that weights 1-2 kg. This is a rough guess >> and the actual force varies during the compression cycle but you get the >> idea. >> >> For the wheels, I can try to make sure that the brakes are always >> slightly set, but what do I do for the prop? >> >> Cheers, >> Vik >> >> On 07/05/2012 03:30 PM, Emilian Huminiuc wrote: >>> On Thursday 05 July 2012 15:21:24 Viktor Radnai wrote: 1. When the aircraft is parked with no parking brake, it will usually start to roll slowly backwards -- pushed by the wind and maybe the runway slope. If I start the engine on idle, the thrust generated by the idle prop might stop this roll. On tarmac, even a 3 knot wind is enough to start pushing the plane back. On grass more is needed -- maybe 20 knots? >>> Hi, >>> >>> In that case, even in real life, there's no other friction at play than the >>> friction inside the wheel bearings, friction which is very low, almost >>> ignorable. >>> >>> Regards, >>> Emilian >>> >>> -- >>> Live Security Virtual Conference >>> Exclusive live event will cover all the ways today's security and >>> threat landscape has changed and how IT managers can respond. Discussions >>> will include endpoint security, mobile security and the latest in malware >>> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ >>> ___ >>> Flightgear-devel mailing list >>> Flightgear-devel@lists.sourceforge.net >>> https://lists.sourceforge.net/lists/listinfo/flightgear-devel >>> >> -- >> Live Security Virtual Conference >> Exclusive live event will cover all the ways today's security and >> threat landscape has changed and how IT managers can respond. Discussions >> will include endpoint security, mobile security and the latest in malware >> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ >> ___ >> Flightgear-devel mailing list >> Flightgear-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/flightgear-devel > -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] scenery licence for 2.8 and later
> > And Keep It Stupid Simple (tm). One license is already too > many licenses. > Everything on GPL only means: - less scenery and airplanes included ( wasn't there recently some photoscenery rejected because of the GPL?) - authors lose copyrights - only to find their work rebranded and sold for ex. as flightprosim etc. Having only the code on GPL and everything else as freeware...seems less narrow minded to me. -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Yasim static friction?
Does this happen only left wind, right? Or happens on right wind too? Hyde (2012年07月05日 10:02), Viktor Radnai wrote: > Technically, you also have the compression of the wheels -- when the > wheel turns, part of the tire in the front gets compressed while the > back gets uncompressed. This is also a friction loss. Plus there is some > friction between the rubber and the road. > > But my point is that the amount of friction is wrong. The plane should > not start rolling with a 3 knot wind, that's nonsense. > > Static friction is greater than dynamic friction. If you stop your car > on moderately flat terrain with no brakes, it will not start to roll > easily, not even if it's windy. If the terrain is flat, it will stay > put. If the slope is greater, it might start to roll very slowly with > the bearings turning in "stick/slip" mode and then finally it will just > roll and accelerate. So the plane should stay put until there's a 20-30 > knot wind blowing against it. Probably more on grass. On grass with the > real plane you might need half throttle or more to get it moving. The > funny thing is that this part seems to be modelled correctly in > Flightgear, so no idea what's wrong with the effect of the wind :) > > Same goes for the prop, the resistance the shut down engine offers is > too small and so it's turned over way too easily. Turning the prop of > the Falke at about 2/3 of its span requires about the same amount of > force as lifting an object that weights 1-2 kg. This is a rough guess > and the actual force varies during the compression cycle but you get the > idea. > > For the wheels, I can try to make sure that the brakes are always > slightly set, but what do I do for the prop? > > Cheers, > Vik > > On 07/05/2012 03:30 PM, Emilian Huminiuc wrote: >> On Thursday 05 July 2012 15:21:24 Viktor Radnai wrote: >>> 1. When the aircraft is parked with no parking brake, it will usually >>> start to roll slowly backwards -- pushed by the wind and maybe the >>> runway slope. If I start the engine on idle, the thrust generated by the >>> idle prop might stop this roll. On tarmac, even a 3 knot wind is enough >>> to start pushing the plane back. On grass more is needed -- maybe 20 knots? >>> >> Hi, >> >> In that case, even in real life, there's no other friction at play than the >> friction inside the wheel bearings, friction which is very low, almost >> ignorable. >> >> Regards, >> Emilian >> >> -- >> Live Security Virtual Conference >> Exclusive live event will cover all the ways today's security and >> threat landscape has changed and how IT managers can respond. Discussions >> will include endpoint security, mobile security and the latest in malware >> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ >> ___ >> Flightgear-devel mailing list >> Flightgear-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/flightgear-devel >> > -- > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > ___ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/flightgear-devel -- ** Hyde Yamakawa 308 Brookewood Dr. Peachtree City, GA 30269 Phone (770)632-6461 Cell (404)353-8758 e-mail: h...@hyde-tech.com http://www.hyde-tech.com/ ** -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Yasim static friction?
Technically, you also have the compression of the wheels -- when the wheel turns, part of the tire in the front gets compressed while the back gets uncompressed. This is also a friction loss. Plus there is some friction between the rubber and the road. But my point is that the amount of friction is wrong. The plane should not start rolling with a 3 knot wind, that's nonsense. Static friction is greater than dynamic friction. If you stop your car on moderately flat terrain with no brakes, it will not start to roll easily, not even if it's windy. If the terrain is flat, it will stay put. If the slope is greater, it might start to roll very slowly with the bearings turning in "stick/slip" mode and then finally it will just roll and accelerate. So the plane should stay put until there's a 20-30 knot wind blowing against it. Probably more on grass. On grass with the real plane you might need half throttle or more to get it moving. The funny thing is that this part seems to be modelled correctly in Flightgear, so no idea what's wrong with the effect of the wind :) Same goes for the prop, the resistance the shut down engine offers is too small and so it's turned over way too easily. Turning the prop of the Falke at about 2/3 of its span requires about the same amount of force as lifting an object that weights 1-2 kg. This is a rough guess and the actual force varies during the compression cycle but you get the idea. For the wheels, I can try to make sure that the brakes are always slightly set, but what do I do for the prop? Cheers, Vik On 07/05/2012 03:30 PM, Emilian Huminiuc wrote: > On Thursday 05 July 2012 15:21:24 Viktor Radnai wrote: >> 1. When the aircraft is parked with no parking brake, it will usually >> start to roll slowly backwards -- pushed by the wind and maybe the >> runway slope. If I start the engine on idle, the thrust generated by the >> idle prop might stop this roll. On tarmac, even a 3 knot wind is enough >> to start pushing the plane back. On grass more is needed -- maybe 20 knots? >> > Hi, > > In that case, even in real life, there's no other friction at play than the > friction inside the wheel bearings, friction which is very low, almost > ignorable. > > Regards, > Emilian > > -- > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > ___ > Flightgear-devel mailing list > Flightgear-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/flightgear-devel > -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] Yasim static friction?
On Thursday 05 July 2012 15:21:24 Viktor Radnai wrote: > 1. When the aircraft is parked with no parking brake, it will usually > start to roll slowly backwards -- pushed by the wind and maybe the > runway slope. If I start the engine on idle, the thrust generated by the > idle prop might stop this roll. On tarmac, even a 3 knot wind is enough > to start pushing the plane back. On grass more is needed -- maybe 20 knots? > Hi, In that case, even in real life, there's no other friction at play than the friction inside the wheel bearings, friction which is very low, almost ignorable. Regards, Emilian -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
[Flightgear-devel] Yasim static friction?
Hi all, I have a Yasim question I can't figure out from the documentation. We're working on the sf25b and noticed that both that, and the Grob g109 (which is a similar aircraft so we use it to reference things) seem to suffer from "lack of static friction". I might be misinterpreting the issue, but here's what I've got: 1. When the aircraft is parked with no parking brake, it will usually start to roll slowly backwards -- pushed by the wind and maybe the runway slope. If I start the engine on idle, the thrust generated by the idle prop might stop this roll. On tarmac, even a 3 knot wind is enough to start pushing the plane back. On grass more is needed -- maybe 20 knots? 2. When the aircraft is stopped with the engine off, the prop is turned by the wind. A wind of 3 knots will turn it very slowly (maybe 1 RPM), a wind of 25 knots will turn it a lot faster. 3. The prop will windmill forever. On this particular aircraft, somewhere between 40 and 50 knots the prop should stop windmilling, and stay stopped until about 70 knots, where it should start turning around very slowly, and possibly start windmilling again at faster speeds. I don't see any obvious properties to set to take the engine's resistance to turning over, or the friction of the wheels into account to stop these unrealistic things from happening. How should I go about fixing them? Thanks for your help in advance. Cheers, Vik -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
[Flightgear-devel] Jsbsim Caster
Caster, in particular for nose gear aircraft, seems to me to be broken in JSBsim. Can anyone confirm this ? Thanks Alan-- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
