MPS development

[GLS]

I have added two functions for you, to manipulate the SSME data in a safe and transparent way:

class SubsystemDirector
{
public:
    /**
     * @param usMPSNo numerical ID of the SSME
     * @param fThrust0 Vacuum thrust
     * @param fISP0 Vacuum ISP
     * @param fISP1 Sealevel ISP
     * @return false for failure, true for success
     */
    bool SetSSMEParams(unsigned short usMPSNo, double fThrust0, double fISP0, double fISP1);
    /**
     * @param usMPSNo numerical ID of the SSME
     * @param dir direction vector of the SSME force vector
     * @return false for failure, true for success
     */
    bool SetSSMEDir(unsigned short usMPSNo, const VECTOR3& dir);
};

With this, you can now change the engine parameters. You will not be able to directly access the ET, this will be done internally. For the future, the ET propellant resource will not get deleted after ET separation. Instead, we can use it for also representing the mass of the propellant stored inside the lines in the aft compartment - which will be important during the MPS dumps.

For the implementation of the ET and the propellant management system, just tell me how it would be best for you to get the data of the ET.

So, I call SetSSMEParams from the constructor, forget about the funct Realize and all engine creation activities, and SetSSMEDir is for use in the ATVC, correct??

I haven't really made a lot of thinking about the ET and PMS... for a simple MPS dump (no He use in the first version...) I would need the ET handle (both on MPS and SSME classes) and when the dump is comanded the vlvs open and I would decrement the prop.... is the vent propulsive? If it is, then I could create a little weak thruster (on the engines and LH2 dump port) with exhust and it would make it both simpler and pretty!:speakcool:

 

[DaveS]

So, I call SetSSMEParams from the constructor, forget about the funct Realize and all engine creation activities, and SetSSMEDir is for use in the ATVC, correct??

I haven't really made a lot of thinking about the ET and PMS... for a simple MPS dump (no He use in the first version...) I would need the ET handle (both on MPS and SSME classes) and when the dump is comanded the vlvs open and I would decrement the prop.... is the vent propulsive? If it is, then I could create a little weak thruster (on the engines and LH2 dump port) with exhust and it would make it both simpler and pretty!:speakcool:

Speaking of venting how about adding something like this:

[ame="http://www.youtube.com/watch?v=8MZZ29U-WFY"]YouTube - STS-122 - EXTERNAL TANK HANDHELD Video[/ame]

 

[Urwumpe]

GLS: In the constructor, this function would not have any effect. I can include you a function to define the creation parameters for the SSMEs, but they will not exist in the constructor.

Speaking of venting how about adding something like this:

Wow, this is really impressive!!!

How do they vent the stuff, I would have expected a large cloud by it, but the brightness is more than I expected, is it combusted partially? And I thought the vent valves are at the top of the ET, but this looks like they are at the intertank.

And do I see a small trail of hydrogen in the video? The oxygen is easy to notice as it is sky blue, but there is also a transparent flow.

 

[GLS]

Yeah, I think that won't be hard to make, create a little thruster and make a wacky function to control it... I could do it as a sort of test for the MPS dumps!

 

[Urwumpe]

Yeah, I think that won't be hard to make, create a little thruster and make a wacky function to control it... I could do it as a sort of test for the MPS dumps!

Well, if the MPS dump of the Shuttle looks even only slightly similar, it will be impressive.

 

[Donamy]

Ice debri would look cool.

 

[Urwumpe]

Ice debri would look cool.

Except some simple particle effects during MECO, it would become hard.

 

[Donamy]

Dennis,

Did you see my post in the development thread, about the CBs ?

 

[DaveS]

Except some simple particle effects during MECO, it would become hard.

MECO? Heck no! I have a video of the PLBD opening during STS-107 and it shows ice debris coming from the aft of the orbiter during PLBD opening.

 

[Urwumpe]

Dennis,

Did you see my post in the development thread, about the CBs ?

Not yet, reading.

 

[GLS]

Just uploaded the ET vent.
Could someone with mesh viewing software get the exact coordinates of the ET side panel and update the position of the vent? Thanks!


Urwumpe: did you read my questions regarding your new MPS functs??

 

[DaveS]

Just uploaded the ET vent.
Could someone with mesh viewing software get the exact coordinates of the ET side panel and update the position of the vent? Thanks!

That would be as the ET is mine. Here you go: 3.456, -2.074, 5.716.

 

[Urwumpe]

Urwumpe: did you read my questions regarding your new MPS functs??

Yes, I think I already answered them, but if the answer was too brief, feel free to ask more questions. Basically, you should call them from the Propagate() function (as this is the transition from the last state to the next). But Prestep() would also be good. PostStep() will be too late.

 

[GLS]

That would be as the ET is mine. Here you go: 3.456, -2.074, 5.716.

Thanks!!!
New version is up!

 

[GLS]

Yes, I think I already answered them, but if the answer was too brief, feel free to ask more questions. Basically, you should call them from the Propagate() function (as this is the transition from the last state to the next). But Prestep() would also be good. PostStep() will be too late.

Wait a minute, is the SetSSMEParams to create the engine or to set it's state during the flight (throttles)??? From the looks of it, it looks like it's to create the engine, but now you say call it from the time step functs... and also I need the handles for throttle...

I'm sorry to bother you again with this but wouldn't it be simpler to create the SSME, then the EIU (passing the SSME pointer from data/cmds) and the the ATVC (passing the SSME pointer so ATVC can get the thruster handle, which would be on public access inside SSME)?

 

[Urwumpe]

I'm sorry to bother you again with this but wouldn't it be simpler to create the SSME, then the EIU (passing the SSME pointer from data/cmds) and the the ATVC (passing the SSME pointer so ATVC can get the thruster handle, which would be on public access inside SSME)?

No.

Allowing direct access would make transparent testing of the MPS code impossible, also, the responsibility for the thruster belongs to the Atlantis vessel class. Letting the MPS handle the creation and control the SSME thruster will not be simpler.

 

[GLS]

No.

Allowing direct access would make transparent testing of the MPS code impossible, also, the responsibility for the thruster belongs to the Atlantis vessel class. Letting the MPS handle the creation and control the SSME thruster will not be simpler.

sorry about the delay... I was taking a shower...

OK... so going back to your functs:
1) What's the purpose of SetSSMEParams? (my guess: engine creation)
2) If my guess above is correct, how do I get/set engine throttle??

 

[Urwumpe]

sorry about the delay... I was taking a shower...

OK... so going back to your functs:
1) What's the purpose of SetSSMEParams? (my guess: engine creation)
2) If my guess above is correct, how do I get/set engine throttle??

1) Change engine parameters during runtime. Or for overriding engine creation values.
2) No function yet for throttle, but can be added quickly.

In case of a 3)

3) I will add you a function to define the creation parameters of the SSMEs, will come together with the SetSSMEThrustLevel function.

 

[GLS]

1) Change engine parameters during runtime. Or for overriding engine creation values.
2) No function yet for throttle, but can be added quickly.

In case of a 3)

3) I will add you a function to define the creation parameters of the SSMEs, will come together with the SetSSMEThrustLevel function.

Well, I really don't see a need for overriding engine parameters in "realtime"...... anyway check back when you're done so I can do my side of it... meanwhile I'm going to finish work on the my wacko valve position tables for shutdown....:axehead:

 

[Donamy]

I get:

KU yaw

Rot point = 2.48 1.83 10.32

Rot vector = -0.411587 0.911371 0



KU roll

Rot point 2.41 2.03 10.53

Rot vector = 0 0 -1