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euroastar350
August 4th, 2010, 20:33
To all design gurus out there,

This is my last resort to get some answers relating to our Bell 222 project and the landing gear problems we are facing.

The dilema is this. The gear is animated in gmax (0-100 gear retracted/extended), (101-200 gear compression). I have all proper tags on the gear parts.

Now I export to FS9 and the gear does not work. I have the proper contact point entries within the aircraft configuration.

I've posted this same dilema over at FS Developer and Free Fligt Design with no responses from either source.

So far the only folks that have tried to help has been Lionheart, Thomas Ruth, Alan Devins..but no luck still.

I don't want to abandon this project, but I feel like I am not getting no answers from anyone more experienced then myself. This is my first go at gmax and the first 2 phases have been completed (3DS Max conversion and texture mapping).

I am willing to send the files to anyone willing to look at the gear to see where my problems are hiding.

Please help:confused:

hairyspin
August 4th, 2010, 21:51
This being summer in the northern latitudes, lots of people are building BBQs instead of models, but I had a look at your posts at ffds and fsdeveloper and something n4gix said recently rings a bell - in FSX it's not enough to put keyframes for the start and end positions of an animation, you have to set some intermediate keys as well.

So, you'd have keys at (say) frames 0, 25, 50, 75 and 100 for the retraction and frames 100, 125, 150, 175 and 200 for gear compression. This is all clearly documented in the SDK on page 1744, paragraph 18...... :mix-smi:

That's where I'd suggest starting, but I've still to start modelling for FSX so these are guesses. n4gix is the master where FSX is concerned.

HTH

euroastar350
August 4th, 2010, 22:13
This model is for FS9 first, then FSX.

hairyspin
August 5th, 2010, 07:39
Then I'd check very carefully the names applied to the gear objects. That's where many of us go wrong. Check the FS9 SDK, or have a quick look here:- http://www.flightsimonline.com/C162/anim/index.htm (http://www.flightsimonline.com/C162/anim/index.htm)

It'll work in gmax regardless, but in the sim only if correctly named and keyframed.

Lionheart
August 5th, 2010, 08:16
Parts number is also of 'key importance', no pun intended.

c_gear_01 is correct
c_gear 01 is not
c_gear_1 is not
Also, if you are adding verbage discriptions to the end of landing gear names, you will need to experiment to make sure your naming system is working. If the landing gear stops working, then you know you labled them in such a way as to stop them from working. Go back to simple name tags with name and number; c_gear_01, l_gear_24, etc.

When animating, KF (key frame) zero is 'gear up' and KF 100 is gear down/fully extended, and KF 200 is fully compressed, maximum shock/oleo 'pressed' up as high as possible (full impact).


When animating in Gmax for landing gear that retract, Bill Leaming taught that you can move 'backwards' on the gear retraction and use the 'degree's in the rotation lower windows coordinates boxes to move the landing gear, so you do not lose your exact points of 'retracted' mode.

Example: Select landing gear, Animation mode 'off', KF position zero, select RH control panel/Animation tab/'Create Key; Position. Then do this for KF 100, and then KF 200.

Next, KF slider to zero, turn on Animation mode, rotate landing gear up into landing gear bay noting the degree's its turned total when you stop. (It disappears when you stop, so be fast to read it. If you mess up, click undo to reset back to position and repeat). Click Animation; Create Key; Rotation. Next, move to KF 100, rotate landing gear back out same amount of degrees to orignal 'down' angle point. Click on Create Key; Rotation again to lock that point.

Done.

For slider landing gear, such as c_gear_02 (oleo part of lower section of a gear leg that compresses), you would animate at point 100 to point 200. You will need to put in KF zero, with Position and Rotation locks/points added so that it doesnt move from zero to 200, but from 100 to 200.

Hope that helps. It can be difficult. I hate it when they start rotating backwards and things when you have a difficult landing gear that needs say 10 KF's between zero and 100... Always have to start over and go from zero to 200 in order or it flips out the animation.

Note that you can delete 'Rotation' lock points in such an order as to get your landing gear doors back to 'flush'. Never lose your landing gear doors 'flush' point. That is all important. You will 'never' get them back to flush again, so be careful.. If you do lose it, just go back a save and start over.


Bill

N2056
August 5th, 2010, 15:15
Could you post your aircraft.cfg?

Hughes-MDflyer4
August 5th, 2010, 15:21
I've solved the problem...kinda. I made a little box, named it correctly, linked the gear to it, and animated it. The gear then worked. So, from the 3Ds to gmax conversion, something was done to the gear objects themselves that made them not want to animate. We are still not out of the woods. The gear will surely give us more trouble while we get little animated boxes in there rather than animating the gear parts themselves.

N2056
August 5th, 2010, 15:54
Well, if you got motion then I doubt it's a .cfg issue :salute:

Milton Shupe
August 5th, 2010, 17:33
I would be happy to look at the gmax source for the gear.

No need to send the whole model.

hairyspin
August 9th, 2010, 11:38
Aarrggghhhh! Memory shifts a cog and turns...

IIRC, animations in FS9 linked to dummies don't work, whereas in FSX they do - and in CFS3 for that matter. Better late than never. :redface:

Milton Shupe
August 9th, 2010, 15:40
I looked at the model gmax source and could not get it to work without rebuilding the parts. I could merge in my gear and they worked fine but even after deleting all animations and redoing them, I could not get them to work. I tried resetting transforms but still no go. Something about the gear construction is strange but I could not put my finger on it. Needless to say, I was very disappointed that rebuilding the gear might be the only way to get them working.

euroastar350
August 10th, 2010, 00:48
Milton,

If we delete the existing animations, can we get it to work by re-animating them or do they need a rebuild? I would hate to re-build the gear...but if that is the last resort, then so be it.

Another quick question. I want to add forward/aft, left/right cyclic control to the main rotor, what is the correct sequence when animating the rotorhead?

I already animated the blades to have collective pitch and added a prop0_blurred tag to the entire rotor...works like a charm:ernae:

Milton Shupe
August 10th, 2010, 09:52
Milton,

If we delete the existing animations, can we get it to work by re-animating them or do they need a rebuild? I would hate to re-build the gear...but if that is the last resort, then so be it.

Another quick question. I want to add forward/aft, left/right cyclic control to the main rotor, what is the correct sequence when animating the rotorhead?

I already animated the blades to have collective pitch and added a prop0_blurred tag to the entire rotor...works like a charm:ernae:

I tried deleting all the animations and redoing them from scratch and that did not work.



One thing you can try that would be easy and non-disruptive to existing animations.
Take for example the l_gear_upper.
Select any subobject poly or its top cap,
Now select invert to select the remaining.
Detach those polys to an object called lgearupper.
Link this back to l_gear_upper.


By doing this, the pivot and animations stay intact for the original gear and if this is a geometry issue, then this technique should work.

For you blade assembly animations, you should be able to use the same tags as for the interior:

Clutch (Helicopter Specific) R22 Switch_Clutch Key 0 = Off, Key 50 = On
Collective Arm Bell\Robinson Lever_Collective Key 0 = Control Down (No Rotor Pitch), Key 100 = Control Up (Max Rotor Pitch)
Collective Throttle Bell\Robinson Lever_Collective_Handle Key 0 = Throttle Closed, Key 100 = Throttle Open
Right Trim (R22 Specific) R22 Lever_R22_Rotor_Trim Key 0 = off, Key 100 = on
Rotor Brake Robinson R22 Lever_Rotor_Brake Key 0 = Off, Key 100 = On

For fore/aft/left/right, just create two small bits of geometry and link one to the other. Name them appropriately and link yor main visible parts to these. Like for yoke sticks, we would use:
Lever_Stick_Fore_Aft as parent of
......Lever_Stick_L_R
Not sure what you use on a heli.

Let us know how this goes please.

Hughes-MDflyer4
August 10th, 2010, 10:39
I've been working on rebuilding the gear from scratch. It's probably the best thing to do.

hairyspin
August 10th, 2010, 12:29
This model was originally built in 3ds Max 9 and exported to gmax using the BFF script. Tonight I got access to a Max installation again and had a look at the animations.

They're done with Euler rotation controllers (wot?) and the useful article on BFF at FFDS says this about animations:-



The original BFF page states that it will successfully export Position, Rotation, and Scale animations PROVIDED that they have been assigned TCB controllers, however in my experience they still do not work.


So the animations need to be converted before export, or the export could be done without animations. What to do now??



Suggestions:
Re-export the gear objects from Max, minus the animations, and merge them into the gmax model. Then re-animate in gmax.
This is a longer shot - having deleted the animations from the gmax model, select each previously animated part and click Collapse (Motion panel, Trajectories tab). I used this to remove the traces of animation controllers used in gmax that a simple delete wouldn't remove.
HTH

hairyspin
August 10th, 2010, 14:04
HANG ON!

The animations work correctly in gmax? Milton, we've been here before! There are animation controllers or constraints being used here and they have to be reduced to keyframes.

I built the gear animations for my Tempest using Look At constraints and its animation wouldn't work in the sim until reduced to simple keyframes.

http://www.sim-outhouse.com/sohforums/showthread.php?t=7288&daysprune=-1 (http://www.sim-outhouse.com/sohforums/showthread.php?t=7288&daysprune=-1)

I think the answer to the Bell problem is to Collapse the animations to keyframes.

Milton Shupe
August 10th, 2010, 16:32
This model was originally built in 3ds Max 9 and exported to gmax using the BFF script. Tonight I got access to a Max installation again and had a look at the animations.

They're done with Euler rotation controllers (wot?) and the useful article on BFF at FFDS says this about animations:-


So the animations need to be converted before export, or the export could be done without animations. What to do now??



Suggestions:
Re-export the gear objects from Max, minus the animations, and merge them into the gmax model. Then re-animate in gmax.
This is a longer shot - having deleted the animations from the gmax model, select each previously animated part and click Collapse (Motion panel, Trajectories tab). I used this to remove the traces of animation controllers used in gmax that a simple delete wouldn't remove.
HTH

I saw the Euler controller and thought that might be an issue. That's why I deleted all the animations and started over, only not to work. BUT, I forgot to check if the default controller was used.

This is likely the issue.

EDIT: Okay, verified that the Euler controller is the issue. I Collapsed the Transforms and the gear worked fine. You must do this on each animated part but it only takes a few seconds each. Works in FS here.

euroastar350
August 10th, 2010, 23:52
YAY!!! Thanks Uncle Milton and Hairyspin!!! I have gear now that retracts and extends:ernae: Only drawback is the the left upper gear strut is not animated, the nose gear does not have any steering animations and I don't have compression....any ideas?

Lionheart
August 11th, 2010, 01:29
Congrats Euro. Great to hear you have it partially working now.

For rotating gear (nose gear), I like a part to a sub part named 'rudder_01' or 'rudder_key_01' if you want to animate it. On the regular rudder, you do not need to animate, and you 'do' need to flip the Gizmo for blue to be pointing down instead of up when its a nose gear, (turns in opposite direction of the rudder).

This entire episode sounds like the old Max Mirror pre-Max 6 issue. Some odd things happen with models when put into FS9 and FSX...

euroastar350
August 11th, 2010, 01:40
Thanks Bill,

I got the compressions working now on the mains, need to test the nosegear now. The upper left gear strut now refuses to come down and play nicely with the other parts, I am looking into the issue...gotta remember that this is my first try in gmax and I must say that I am learning this quite good:ernae: I don't know how you guys do it with this program, some sort of separate brain or super power...LOL!!!

hairyspin
August 11th, 2010, 10:02
YAY!!!

You're welcome! :wavey:

Milton Shupe
August 11th, 2010, 16:23
Thanks Bill,

I got the compressions working now on the mains, need to test the nosegear now. The upper left gear strut now refuses to come down and play nicely with the other parts, I am looking into the issue...gotta remember that this is my first try in gmax and I must say that I am learning this quite good:ernae: I don't know how you guys do it with this program, some sort of separate brain or super power...LOL!!!

Make sure that the Local Coordinate Pivot is aligned with world and that the TCB controller is used.

euroastar350
August 11th, 2010, 22:01
Landing gear fixed and ready to roll. Now to adjust the contact points so the main wheels are actually touching the ground.

A big thanks to Milton Shupe and Hairyspin for all the advice and tricks in getting the gear to finally come down, couldn't have done it without you 2 fine gentlemen.
If you guys were close by, I'd buy you a cold one:ernae: