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Old 08-19-2016, 06:31 AM   #91
Thorsten
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That's appreciated of course :-)

In any case, I feel it can't hurt to explain why I do something a certain way, just as it can't hurt to challenge that. How else do we learn anything?
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Old 08-19-2016, 06:37 AM   #92
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Looking foward to future updates,great job.
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Old 09-08-2016, 05:43 PM   #93
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PDRS control joins the SM DPS pages:



The operator commanded AUTO mode is actually functional, you can simply enter a target and the RMS arm will move there (or run into software stop on the way if it's not inhibited). There's also a simple reach limit test available.

The complete automatic modes are not done yet, but a fairly trivial extension - just need a script to push one point after the next (admittedly I don't have any use case yet...).

In case I never mentioned it before - I really really hate the trigonometry underlying the RMS arm movement control - it's so easy to make a mistake which screws everything...
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Old 09-10-2016, 05:49 PM   #94
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Wayne has done it - the rear flight deck mesh is in.



Lots of work ahead with texturing and making it functional, but one big step is taken.
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Old 09-28-2016, 09:50 AM   #95
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I've spent some time with the cabin environment simulation, and I would like to pose a question to the community.

So far, the system simulates the valves of the oxygen and nitrogen system and uses O2 and N2 partial pressure data to decide upon oxygen/nitrogen flow if the O2/N2 manifold valves are in auto, otherwise just feed oxygen or nitrogen to hold the pressure.

If the sim is confronted with a leak, the controllers first up the flow rates to hold pressure. If there's more than ~6 lb/h loss, the increased flows trigger the CWS. The controllers up the flow to as much as 75 lb/h to keep pressure, then it drops from 14.7 psi, at 8 psi the emergency oxygen feed opens and adds another 75 lb/h (at which point overall reserves deplete pretty quickly). For a loss of more than 150 lb/h, the cabin will eventually depressurize (which also happens if you're dumb enough to open the vent valves in space).

My question is - what then?

What would you expect from a sim if the cabin de-pressurizes beyond alarms going off all over the place and the ambient sounds gradually fading out? I guess in theory the crew could slip into space suits and continue to operate for a while - but the urgency of the real situation wouldn't really be felt in the sim.

Does any Orbiter craft simulate that situation?
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Old 09-28-2016, 10:39 AM   #96
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Quote:
Originally Posted by Thorsten View Post
 My question is - what then?

What would you expect from a sim if the cabin de-pressurizes beyond alarms going off all over the place and the ambient sounds gradually fading out? I guess in theory the crew could slip into space suits and continue to operate for a while - but the urgency of the real situation wouldn't really be felt in the sim.
If the crew has the time for that and can get suited up and connected to the Orbiters oxygen system in that time, the backup oxygen of the ACES suits is limited to only 10 Minutes. AFAIR, there is an emergency procedure in the FDF that describes exactly that scenario and how to behave if there is enough time. If you are fast enough, you can let the cabin depressurize and limit the Orbiters oxygen to the ACES.

See here for some details about the ACES and proposed modifications for Orion:

http://ntrs.nasa.gov/archive/nasa/ca...0140010572.pdf

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 Does any Orbiter craft simulate that situation?
Not that I know. Some simulate life-support in a "alive or dead" style, but not as a gradual degradation of performance and health.
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Old 09-28-2016, 02:32 PM   #97
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Quote:
Originally Posted by Urwumpe View Post
 ...Not that I know. Some simulate life-support in a "alive or dead" style, but not as a gradual degradation of performance and health.
IIRC, Dansteph's DGIV has some sort of health degradation.
My poor XR Fleet astronauts have died several time of hypoxia too.
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Old 09-29-2016, 05:56 AM   #98
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Quote:
See here for some details about the ACES and proposed modifications for Orion:
Made for some interesting read, thanks...

Essentially that'd mean adding a simple suit simulation... perhaps add a 'helmet from inside' frame to the rendering camera, change the sound environment to hear your own breathing... Something like that.
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Old 09-30-2016, 06:56 AM   #99
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Environment system is now hooked up to the avionics - most importantly DISP 66.

For those who enjoy the technicalities - the display as posted shows the effect of vent isolation and vent valve opened in orbit - large negative pressure change, cabin pressure dropped to 11.6 psi already, oxygen partial pressures dropping in sync.

N2/O2 valve is set to full oxygen to get partial pressure up, the system is injecting 75 lb/h into the cabin to stabilize partial pressure (but the vent valve is much faster of course). Keeping this up, one could stabilize cabin pressure at 10.2 psi in preparation for a scheduled EVA (I was surprised to read that this can't be done automatically - the atmosphere really needs to be managed manually for this - though in reality the airlock valves would be used to decrease pressure rather than the vent valves.




Incidentially - that's now screen number 40 of the avionics that's implemented (MEDS and DPS pages taken together that is).
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Old 10-02-2016, 04:49 PM   #100
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Managed to beat the PDRS automatic sequences int submission. Now you can i-load any set of points and have the RMS arm go through them automatically.

If I were to nominate any subsystem of the Space Shuttle for most annoying to code, I think the whole RMS arm code would score pretty high...
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Old 10-04-2016, 11:27 AM   #101
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I can't resist showing those. Wayne has made it is personal quest to implement the lighting of the Shuttle cockpit as it really works (and even extended the GLSL shader to support more light sources to get it done).

Now every single button and rotary knob adjusts light as it should be - all dim switches are working, it's possible to change instrument lighting as well as back-lighting of the labels, operate the fluorescents and the incandescents independently... it's pretty much a work of art (I dare say it's the most sophisticated light concept for any cockpit in Flightgear).

Glareshield light on and panel backlights off CDR side, panel backlights on PLT side:



We could do some work on the lamp objects themselves, right now there's just the emissivity dialed up, but I know the GLSL magic to make lights look like lights - the illuminated console PLT side:



Details with shadows from two different light sources criss-crossing (MDUs are also dimmed compared with the previous shots):

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Old 10-04-2016, 02:55 PM   #102
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Are the shadows baked on the texture, or are they actually from the light source ?
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Old 10-04-2016, 03:04 PM   #103
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They're multi-channel lightmaps generated by a ray tracer run over the cockpit 3d mesh - in my view the technique that will give the best possible visuals.

Edit: In case the tech word 'multi-channel lightmap' isn't clear to everyone - the shadows appear, disappear and dim along with the lights - although the light scattering through the flightdeck (shadows, diffuse reflection,...) is computed offline and then tabulated, light intensity, addition and application to the surface are done runtime. So switching a ceiling light on in the above scene would weaken the existing shadows where the light reaches them and potentially create new ones.

Last edited by Thorsten; 10-05-2016 at 05:29 AM.
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Old 10-08-2016, 09:06 AM   #104
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This might be an odd request, but does anyone know of a 3d model of a spacesuit helmet from the inside that would have a GPL-usable license?
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Old 10-13-2016, 05:27 PM   #105
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Been busy with the nuts and bolts of the thermal simulation of the hydraulics system. The basic idea is that hydraulic fluid can get sticky and freeze, so it needs to be circulated now and then, otherwise no joy in using airfoils during entry...

The system how to keep it warm is actually quite neat, hydraulic fluid passes a heat exchanger with the hot part of the freon loop.

The simulated model is fairly crude, but it does get plausible distributions (and illustrates the need for putting the heat exchanger in...)

DISP 87 is used to monitor it all:



(and no temperature or pressure is fake - they all show the real state of the simulation - the display would also show blown tires and the friction coefficient of a blown tire would be different from a rolling one on the runway, leading to a yawing moment during rollout).

For the test in the screenshot, I've not circulated hydraulic fluid in sys1 for several hours, hence the readings are in thermal equilibrium with the orbiter fuselage - the sun-exposed parts are fairly warm, the shadowed parts are chilly (i.e. you can read off simulated orbiter attitude with respect to the sun from the display). Now circulation pump 1 is struggling to get it all back into shape....

I have to say, it's quite instructive to learn why all the systems aboard the Shuttle work the way they do.
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