Posts by MDIvey

    Hi Matt,


    We're investigating if we can create a repaint kit for the A320. The textures are not as well organized, e.g. the fuselage is cut into several pieces on the texture so that it's not easy to write text on the fuselage. I think we had an Aer Lingus livery at some point during the development but I'm not sure if that is still up to date and could be published or not. We're evaluating this as well.

    Thanks Jan


    that's great on both counts.


    Matt

    1) All the 3rd party repaints for your aircraft, and repaints for 3rd party aircraft (payware and freeware) are not displaying. regardless of where the repaint folders are put.


    2) Scenery problem at Miami Airport

    3) Bit of Wheel showing through left wing on Barron

    4) Some of retracted U/C on F18 is breaking into the intake

    Matt

    Sitting looking at lines of code for an hour this morning I've come to the conclusion that I don't understand this enough for it to be worth me wasting even another week on this so I've reluctantly had to admit defeat and give up. Perhaps Alex will succeed in getting his Mk9 Spitfire done so we can enjoy flying that in AF2 but I'm afraid my models wont be making it into AF2 skies. Sorry.


    Matt

    I spent some more time on this yesterday but it still doesn't work... I really can't see what the problem is. I took the rigid body graphics out for the lower leg and wheel, but had to leave their dynamic sections in or the TMD crashed and the Cessna was loaded. The axis on the joint with fuselage.... can I clarify should be the hinging axis, I.e running roughly front to back... or should it be along the UC leg axis which is sideways in plan view but twisted backward 30deg? In either case to calculate the x0 value I need to get a vector from my spreadsheet using two points along it? R0 can be the pivot given in my spreadsheet or that point on the corner of the door that I've been using? One final query... should the hydraulic cylinder be bent back at 30deg so that it's acting directly inline with the retraction?


    This might give me some things I can try. I'm going to focus on getting this done this week... or at least making some significant progress. If I'm unable well I think it will be quitting time. Whatever happens I do appreciate the help you guys have given me.


    Matt

    This is the code of the joint. R0 I've put in as the xyz co ordinates of the point on the Gear door shown above


    Code
    <[multibody_joint][JointLeftGearFuselage][]
    <[string8][Body0][Fuselage]>
    <[string8][Body1][LeftGear]>
    <[tmvector3d][X0][ 1.0 0.0 0.0 ]>
    <[tmvector3d][R0][0.029 0.844 -0.853 ]>
    <[float64][Kp][0.0]>
    <[float64][Kd][0.0]>
    <[uint32][Type][0]>
    >

    As you say...


    Regarding X0:

    Set a rotation around Z by 30deg and a y rotation by 5 degrees. No additional 90° rotation since the gear is defined in the down state.


    Code
    <[tmvector3d][X0][ 1.0 0.087266 0.523599 ]>


    Is that correct? (radians)

    Matt

    I've re-jigged the model so that using this pivot point on the door (which is now attached to the upper gear)….



    These angles...


    The Gear should tuck neatly away.


    I cant work out how to translate this into what to put into the Matrix Generator... is this right?



    Ive attached the latest version of the TMD, TGI exporterTM Log and Aircraft converter log. Maybe you can make some sense of why its not working?


    Matt


    TMD_Spit_2Aug19.zip

    Another day spent stabbing in the dark and getting nowhere. I don't think I can take much more of this. I know you don't want me to give up and I don't really want to myself but there will come a point where I have to for the sake of my sanity.... my mind is getting like this:)

    Matt

    thanks for suggestions guys... I have some idea of what to try next.


    Steve.... I'm still a bit perplexed by what that X0 value is meant to be. What I actually did was take points from the actual hinging axis for the upper part of the undercarriage and use that vector calculator I made to get the values.... which does point forward more than other directions. I'm getting the impression from what you said that the vector maybe needs to be along the line the undercarriage takes when it's up?


    I think ill try and get the gear to retract just through 90deg first and then if that works hopefully you guys can help me work out how to deal with that compound angle. It's very tricky geometrically, but I understand why it was done.... because of the wing box spar.


    Let you know how it goes.


    Matt

    The Graphic parts do seem to be rigid body graphics rather than say bending body graphics. Comparing different TMD files I notice with bending body graphics an additional code section is needed to specify the rotation axis and pivot and where the angle comes from... where as rigid body graphics don't seem to need this... perhaps because you've already specified that in the dynamics section. I wont mess with this until I've got some feedback from you guys so that I don't waste time going in the wrong direction... but I'm obviously looking for the simplest way of doing this.


    Matt

    Do you have the same pivot point on the lower side of the gear and the upper side of the gear?

    Sylvain ....In answer to your question I'm not sure I have. I took the inertia box size of each object from the information displayed top right in AC3D and the R0 value was the object centre displayed in the object information box. Is that incorrect? Wouldn't be surprised😀

    Matt

    I think I copied the code from the Baron and so I guess the B0 values was omitted. I read somewhere that it can be omitted if the standard matrix is required. You may have a point here Kai. I may have to work out the angles involved and put them into Jans matrix generator. I guess I'd been thinking that as I'd put the axis vector in the joint it wasn't needed. Certainly worth looking further.


    The parts do return to correct position. I will post whole TMD later when I get time so you can see if the graphic bits are wrong.


    Matt

    Here is code for left Gear, rigid body section


    What I thought I'd done and what I've actually done could be very different. I think I've made the pivot an angled axis on the join with the fuselage. The lower gear is joined to the upper and has a linear translation axis that follows the centre of the upper leg. The Hydraulic cylinder should be pulling the gear upward via an offset pivot on the upper leg and the oleo should be placed so as to stop the leg collapsing on itself. The gear looks like below. Ignore the hydraulic cylinder visualization as I changed this to a vertical orientation since you don't see it... adding the parts just help me find the R0 and R1 point values


    Matt....