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Guest iholrf

Telescopic oleos (sp?)

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Guest iholrf

You know you're addicted when you dream about GMAX. I kid you not. I dreamed I had completed the reflective glass textures for the model and was so excited. I was oooing and ahhhing my amazing work when I woke up... you can imagine my disappointment.Anyway, my real question is, what is involved in making telescopic oleos? The reason I ask is this:I was about to resize the main gear struts as they are too long which results in the nose pointing much to high while on the ground (being a tail dragger this of course is completely unwelcome). Then it occurred to me that it wasn't the length of the strut that was the problem (it is right when in flight and extended i.e. gear down), but the fact that it should compresses from 4 to 6 inches when sitting on the ground. Further if I simply change the length of the strut I then need to change the lower cowling and ...well everything.Is it simply a matter of making an animation and changing something in the cfg, or is it more involved (things are never as easy as they seem).TIAShadPS if it seem like I am bouncing all over the place, well, I am. :) There are often too many gaps in my knowledge to complete a part I am working on, so I try to tackle similar parts in the hopes I can learn and apply the new knowledge back. It is working reasonably well I must say... slowly... but well. And they say you can't teach an old dog new tricks. :)

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Yes, it is a relatively simple and painless process. As nearly always, the procedure is outlined in elegant simplicity at http://freeflightdesign.org in the "Tutorials" section... ;)A couple of part names and some key-frame animation, and the deed will be done! Well, there IS that little bit in the aircraft.cfg's contact section to deal with also... ;)Oh yeah... about the dreams... some of my finest work has been accomplished while dreaming! I kid you not! More often than I care to admit, I've "dreamed the solution" to a vexing problem, only to wake up in the morning and find that... it worked! ;)


Fr. Bill    

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     Avsim Board of Directors | Avsim Forums Moderator

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Guest iholrf

Doh!How did I miss that... er and I think its freeflightdesign.com ;)Thanks BillShad

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Guest iholrf

Jeeze, even comes with source. Very cool.Shad

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Guest iholrf

Hmm, after reading through the tutorial, it appears the animation is already present... of course I may be wrong... no, wait.. it is ... ok, so this is a cfg/airfile problem.Point 1 (Left main)Static Compression=0.900Max/Static compression ratio=2.5Damping ratio=0.900These were assigned based on my examination of other models models (and are likely completely wrong), but the gear seems not to compress on the ground.What is the entry I need to adjust and how should I measure the gear to make sure the cfg is accurate to what was programmed in the model?The tutorial also helped point out that "tire_blurred" was not present (I had wondered why they seemed dead looking by comparison to most), so I do get to model that new part and animation :)ThanksShad

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Guest iholrf

Ok, after much playing, I think I can safely say the animation, while present in gmax is not functioning in the sim. This kind of animation according to the tut, is a key frame, which is different than a normal type animation. Is the problem in the key frame aspect... is there some XML required I don't know about?CheersShad

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Guest iholrf

However I would be wrong... turns out it was simply the max/static compression ratio. Once changed to 1.0 everything started to work. I suspect the 2.5 would accomodate a much heavier plane??Shad

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>However I would be wrong... turns out it was simply the>max/static compression ratio. Once changed to 1.0 everything>started to work. I suspect the 2.5 would accomodate a much>heavier plane??Man, I can't keep up with your questions! ;) There is - somewhere either here or at FFDS - a post that provides a "formula" for calculating the .cfg values...No, key-frame animation doesn't rely on XML at all. The illustrated tutorial should have covered that already.I'm leaving for Oshkosh for the weekend... See ya!


Fr. Bill    

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     Avsim Board of Directors | Avsim Forums Moderator

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Guest iholrf

POST PICS!!!! OF MODEL 18s!!!!!!!!!!!! please :)Do have fun (I am green with envy)Sorry for the stream of questions, Sophie is not here and I have nobody to bounce my thoughts off of. Typing them out helps me keep it all clear :)CheersShad

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Guest Andy Warden

Taken straight from a description by the designer of the yeodesigns 737-200, this method works perfectly."measure the total travel of the animation ....if you measured it in meters.. convert it to feets.. then place the animation where you like how it looks as it were on the ground...(DESIRED AMOUNT) then measure that amount.. in feets.. .. then divide the total between desired amount ... and put the values in desired amount in static compressionand the result between 2 values put it in compresion ratiotheres no need to mention the total amount on the fde.. it is just to make the operation .. to get the compression ratioto get the position of the axis Z (altitude) of the gears .. you should use the uncompressed stage"Works great, especially if you wanna get it to have a little bit of bounce etc

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Guest iholrf

Mmm, about what I eventually came up with on my own. Your method is more precise as I simply guessed at an approximate value based on the demensions I already knew. Thanks for the tip, I will use it a lot I am sure.CheersShad

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>POST PICS!!!! OF MODEL 18s!!!!!!!!!!!! please :)>>Do have fun (I am green with envy)I did have a LOT of fun, and met with many of the "movers and shakers" within the GA and bizjet aviation world. The other ESDG team members and I had a delightful hour with the MSFS development team members who were present at Airventure 2005. It was a very enjoyable and fruitfull trip this year.Sorry, but I was quite literally "walking out the door" when I made my previous post, so I'm just now seeing your request for pictures of the 18... :( Had I known, I would have been delighted to do so... ;)


Fr. Bill    

AOPA Member: 07141481 AARP Member: 3209010556


     Avsim Board of Directors | Avsim Forums Moderator

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Guest iholrf

>Sorry, but I was quite literally "walking out the door" when I>made my previous post, so I'm just now seeing your request for>pictures of the 18... :( Had I known, I would have been>delighted to do so... ;)Dang... oh well. :) Yeah, one of these days I will actually make it to Oshkosh myself begosh! :+CheersShad

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Guest iholrf

>You know you're addicted when you dream about GMAX. I kid you>not. I dreamed I had completed the reflective glass textures>for the model and was so excited. I was oooing and ahhhing my>amazing work when I woke up... you can imagine my>disappointment.Update: The dream was prophetic Bill. Just as you described :) Next to the paint itself, this is the single most dramatic improvement yet.http://forums.avsim.net/user_files/123938.jpg

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