OHM Legacy Touchdown Points 3

[nbcfrosty]

nbcfrosty submitted a new addon:

Legacy Touchdown Points - provides legacy touchdown point behavior for old addons

This addon makes many legacy addons compatible with the latest version of Orbiter by approximating the old touchdown point behavior. Extract in orbiter directory and then activate the module. A good vessel to test this module with is the DGIV.

Read more about this addon...

 

[nbcfrosty]

A trick that goes well with this addon is installing this: https://orbiter-forum.com/resources/multistage2015-for-orbiter-2016.398/

Multistage2015 is almost a drop in replacement for multistage2. Copy and rename the multistage2015.dll file to multistage2.dll, and make sure that the stage.dll and multistage2.dll files are not overwritten from now on. This will allow older multistage2 based vessels to work in Orbiter 2016.

 

[nbcfrosty]

nbcfrosty updated Legacy Touchdown Points with a new update entry:

Bugfix

The touchdown points were not being updated for the first 4 seconds of the simulation. That is now fixed.

Read the rest of this update entry...

 

[nbcfrosty]

Forgot to point out that only vessels with legacy touchdown points are affected by this addon, which means Orbiter 2016 compatible addons that explicitly define their hull themselves are not tampered with.

 

[francisdrake]

Thanks for giving the old touchdown points a try. I liked them very much for simple vessels, and a legacy option should have been part of Orbiter.

Could you maybe provide a very simple vessel, as an example?
I see 3 factors that may influence the old touchdown points:

Size = ; radius of a sphere around the vessel
COG_OverGround = ;as the name says
TouchdownPoints = ; at least 3 points with x,y,z positions each

Do they interfere each other?
Does it matter if the legs stick out of the size sphere?

For example I have a simple addon that intially rests at the COG_OverGround height.
After shortly activating a thruster it drops down to its landing legs position,
but when touching the ground is catapulted at high speed away from the surface.

 

[nbcfrosty]

Sorry for not being clear. This addon only works with the touchdown points, set using SetTouchdownPoints or any other method. If the vessel has less than 4 points defined, which means it's a legacy SetTouchdownPoints call and not the orbiter 2016 call, then the orbiter 2016 SetTouchdownPoints call is done like this:

if (is_tail_lander(p1, p2, p3)) {
        p4 = _V(0, 0, 1);

        static const DWORD ntdvtx_geardown = 4;
        static TOUCHDOWNVTX tdvtx_geardown[ntdvtx_geardown] = {
            {p1, 1e8, 1e6, 3, 1},
            {p2, 1e8, 1e6, 3, 1},
            {p3, 1e8, 1e6, 3, 1},
            {p4, 1e8, 1e6, 3},
        };
        v->SetTouchdownPoints(tdvtx_geardown, ntdvtx_geardown);
    }
    else {
        double ylow = min(p1.y, p2.y);
        ylow = min(ylow, p3.y);
        ylow -= 0.5;
        double absy = abs(ylow);
        static const DWORD ntdvtx_geardown = 4;
        static TOUCHDOWNVTX tdvtx_geardown[ntdvtx_geardown] = {
            {_V(0, p1.y-0.5, absy * 2), stiffness, damping, 1.6, 0.1},
            {_V(-absy * 2, p2.y, -absy * 2), stiffness, damping, 3.0, 0.2},
            {_V(absy * 2, p3.y, -absy * 2), stiffness, damping, 3.0, 0.2},
            {_V(0, absy, 0), stiffness, damping, 3.0},
        };
        v->SetTouchdownPoints(tdvtx_geardown, ntdvtx_geardown);
    }

 

[JMW]

Hi nbcfrosty,
Great addon, thanks for work/publishing.
Have this problem with my F-35B addon though. (uses 2016 touchdown points)
As soon as comes to zero, judders.

Tried with my Mirage addon and a few others and they're fine, so is something peculiar to the F-35B setup.
Any ideas?
Don't lose time if not easy to rectify cos can just disable Legacy addon when flying F-35B.
Thanks again for very useful addon.

 

[nbcfrosty]

Hey JMW. Anyway for me to test this? Is the above F-35 published anywhere so I can try to reproduce the problem?

 

[JMW]

Hey JMW. Anyway for me to test this? Is the above F-35 published anywhere so I can try to reproduce the problem?

Hi nbcfrosty,
Thanks for the response.
No, the only published one is for Orbiter2010 but I'm intending (for years) to release a version for 2016.
On investigation today I've found it's the way I've applied the brake force in this later version that's causing the judder, disabling it cures the problem.
Thanks again for responding so promptly, n happy Orbiting

 

[nbcfrosty]

nbcfrosty updated Legacy Touchdown Points with a new update entry:

improved stability at scenario start

Based on francisdrake's reported observation, now the vessel is landed after the TD points are adjusted if the vessel is doing ground contact and has very low speed. This should prevent the cases where there is a jump due to the TD points being adjusted.

Read the rest of this update entry...

 

[JMW]

nbcfrosty updated Legacy Touchdown Points with a new update entry:

improved stability at scenario start



Read the rest of this update entry...

Hiya,
Version 2 is definitely not for the F-35B
It's not on a loop, this is what actually happens.....

Never mind nbcfrosty, keep up the good work.

 

[nbcfrosty]

Oh no! I made a logical error. This will be fixed soon.

 

[nbcfrosty]

nbcfrosty updated Legacy Touchdown Points with a new update entry:

Fixed a major regression

Fixed a regression in the "land assist" code that helps stabalize and land finicky vessels.

Read the rest of this update entry...

 

[JMW]

nbcfrosty updated Legacy Touchdown Points with a new update entry:

Fixed a major regression



Read the rest of this update entry...

Thankee!
That's much better for my "finicky vessel"