Request UMMU Compatible Helicopter?

[gattispilot]

Thanks. Still have yet to get the Max altitude part done

Great work you're doing here, can't wait to see the finished products.



Looking forward to this one the most. The Dauphin has always been a favorite of mine.

 

[Urwumpe]

Thanks. Still have yet to get the Max altitude part done

simply set maximum thrust of your hover thruster as REFERENCE THRUST / ATM DENSITY. Close enough to real physics. Reference thrust is simply sea level thrust times sea level air density (1.28 kg/m^3)

 

[gattispilot]

So get ATM density. Set max hover to max hover/atm density.

Maybe a copter base is needed

simply set maximum thrust of your hover thruster as REFERENCE THRUST / ATM DENSITY. Close enough to real physics. Reference thrust is simply sea level thrust times sea level air density (1.28 kg/m^3)

 

[gattispilot]

Ok Here I get ATM Density at sea level which is 1.22. I climbed to 5000 and density was .5 So not sure what I need to set

void VESSEL::SetThrusterMax0 (hover th, double maxth0) const

On the Dolphin. I need to redo the mesh. I notice the gear covers do not fit and do not animate. I ran it in Orbiter2006

 

[Urwumpe]

In every timestep, calculate the new maximum possible hover thrust by multiplying your 1.0 kg/m³ reference thrust by atmosphere density. That is really all.

 

[gattispilot]

Thanks. I guess I am confused as to what the reference thrust is?

 

[Urwumpe]

Thanks. I guess I am confused as to what the reference thrust is?

Simple: The maximum thrust of hover thruster at 1 kg/m³ air density. Scale as it suits you. If you want to hover at 50% thrust in some low altitude, use 18 Newton per kg mass of your helicopter.

 

[gattispilot]

Thanks. so
double ATMD1;
ATMD1= GetAtmDensity () ;

ATMadjusted=(8.5e5/ATMD1);


void VESSEL::SetThrusterMax0 (hover th, double maxth0) ATMadjusted

const double PB_MAXHOVERTH =8.5e5;

 

[Urwumpe]

Multiply by density, not divide... density drops with increasing altitude and thrust is proportional to density.

 

[gattispilot]

simply set maximum thrust of your hover thruster as REFERENCE THRUST / ATM DENSITY. Close enough to real physics. Reference thrust is simply sea level thrust times sea level air density (1.28 kg/m^3)

OK I thought this meant / Divide. But I will multiply
I have this here:
void SKYC::clbkPostStep(double simt, double simdt, double mjd)

double ATMD1;
ATMD1= GetAtmDensity () ;

sprintf(oapiDebugString(),"ATMD1 %2.2f ", ATMD1);
double ATMadjusted;
ATMadjusted=(8.5e5*ATMD1);

SetThrusterMax0 (th_hover[0] ,ATMadjusted);

No notice in amount of max hover

 

[gattispilot]

ok Finally got the Dolphin redone. It uses the same textures. Has a new mesh and cfg and dll. same keys as the Seaking and Skycrane.

On the elevated pad on my cargo ship


On the adjusting the max hover thrust:

ATMD1= GetAtmDensity () ;

ATMadjusted=(8.5e5*ATMD1);

SetThrusterMax0 (th_hover[0],ATMadjusted);
//SetThrusterMax0 (hover_th, double maxth0) ATMadjusted

sprintf(oapiDebugString(),"ATM %2.2f ATMADJU%2.2f ", ATMD1,ATMadjusted);

on the ground the ATMD1 is 1.22 and hover is 1040838.31
at 4500km it is .77 656127.20


So I need to scale it. The difference between ground air density and 4500 (Ceiling) is .45

Not sure about the scale but I would think at the ceiling 4500m then maybe .25 of hover

 

[gattispilot]

OK. This is what I have. At ATM 1.22 ground is multiplies by 1.0 and .77 the ceiling it produces only 1/4 of the thrust.

ATMD1= GetAtmDensity () ;

ATMadjusted=(8.5e5*ATMD1);

SetThrusterMax0 (th_hover[0],ATMadjusted);
//SetThrusterMax0 (hover_th, double maxth0) ATMadjusted

sprintf(oapiDebugString(),"ATM %2.2f ATMADJU %2.2f ATM2 %2.2f ATM3 %2.2f", ATMD1,ATMadjusted,ATMD2,ATMD3);
ATMD2=((ATMD1-.77)*2.22);
ATMD3=(ATMD2*8.5e5);
SetThrusterMax0 (th_hover[0],ATMD3);

But the max alt is about 3899. So I may need to increase the end amount. Another issue is at 3899 the copter starts to descend. Not touching the max thruster. She goes from 3899 to about 75 where she starts to climb again. I guess gravity and other forces push her down.

on ground

1/2 way to ceiling

Ceiling

This is stupid but not sure how to load/save the airlock state.

void DOLPHIN::clbkSaveState(FILEHANDLE scn)
{
char cbuf[256];
   



    // ORBITER, default vessel parameters
    SaveDefaultState (scn);
    hUcgo.SaveCargoToScenario(scn);   


     sprintf (cbuf, "%d %0.4f", GEAR_status, GEAR_proc);
        oapiWriteScenario_string (scn, "GEAR", cbuf);

        //sprintf (cbuf, "%d %0.4f", GEAR1_status, GEAR1_proc);
        //oapiWriteScenario_string (scn, "GEAR1", cbuf);



        sprintf (cbuf, " %0.4f",  CABLE_proc);
        oapiWriteScenario_string (scn, "CABLE", cbuf);

             sprintf (cbuf, "%d %0.4f", DOOR_status, DOOR_proc);
        oapiWriteScenario_string (scn, "DOOR", cbuf);

         sprintf (cbuf, "%d %0.4f", GEARCOVER_status, GEARCOVER_proc);
        oapiWriteScenario_string (scn, "GEARCOVER", cbuf);
 
       
    // UMmu, this will save all our members of crew in scenario
    // as airlock state depend of your ship (you may have a real animated airlock)
    // it's your responsabilites to save and reload UMmu's airlock state.
    Crew.SaveAllMembersInOrbiterScenarios(scn);
}
void DOLPHIN::clbkLoadStateEx (FILEHANDLE scn, void *status)
{
    char *line;
    while (oapiReadScenario_nextline (scn, line))
    {
        // call this method to let PayloadManager to load its internal parameters
        PM_LoadState(line);

        // UMMU, Load all saved member from scenario.
        // Return TRUE when a "UMMUCREW" line is encountered
        // FALSE when it must pass this line to you or default parser
        if(Crew.LoadAllMembersFromOrbiterScenario(line)==TRUE)
            continue;
        if(hUcgo.LoadCargoFromScenario(line)==TRUE) // UCGO load cargo
            continue;   


          if (!_strnicmp (line, "GEAR", 4)) {
   sscanf (line+4, "%d%lf", &GEAR_status, &GEAR_proc);
            }

         
         
              if (!_strnicmp (line, "CABLE", 5)) {
   sscanf (line+5, "%lf",  &CABLE_proc);
            }
              if (!_strnicmp (line, "DOOR", 4)) {
   sscanf (line+4, "%d%lf", &DOOR_status, &DOOR_proc);
            }
   
 if (!_strnicmp (line, "GEARCOVER", 9)) {
   sscanf (line+9, "%d%lf", &GEARCOVER_status, &GEARCOVER_proc);
            }



        // ORBITER, unrecognised option - pass to Orbiter's generic parser
   
               
        // ORBITER, unrecognised option - pass to Orbiter's generic parser
        ParseScenarioLineEx (line, status);
    }
SetAnimation (anim_GEAR, GEAR_proc);   
SetAnimation (anim_GEARCOVER, GEARCOVER_proc);       

SetAnimation (anim_DOOR, DOOR_proc);       

SetAnimation (anim_CABLE, CABLE_proc);
SetAnimation (anim_CABLE1, CABLE_proc);
           
    // as airlock state depend of your ship (you may have a real animated airlock)
    // it's your responsabilites to save and reload UMmu airlock state and set it accordingly
    // to your airlock. IE: call here "SetAirlockDoorState" TRUE of FALSE depend
    // of your animated airlock
}

 

[Urwumpe]

Yes, it is about the balance between lift and gravitation. But lift is linear to density.

 

[gattispilot]

So is there a fix other than make the end thrust higher and don't go higher than the ceiling?

 

[Urwumpe]

You could include a second density related factor to describe engine power and how it declines at decreasing altitude and increasing temperature.

But I don't know how the relation was like. I would expect it to be linear with density, since less air per volume means also less combustion in the engine... so you could replace the linear relation by REFERENCE_THRUST * pow(ATM_DENSITY, 2) ... but then you also need less engine power to rotate the rotor at the same speed at higher altitude.

 

[gattispilot]

I rescaled and now the ceiling is around 4400. give the dolphin a try. If it works then I will change the skycrane and sea king.

Here is another copter that I am working on the Chinook Ch47 I am going for the NASA one.
http://www.chinook-helicopter.com/history/aircraft/B_Models/66-19138/66-19138.html

Which raises 2 questions. On the rear there is a ramp. But it appears the upper part goes up or into the ramp?
What font does NASA uses to get the red NASA?

I like the bigger rear wheels so it does slant back.

 

[PhantomCruiser]

Hey guys... I'm not sure what I'm doing wrong...

On a clean Orbiter install (with only sound and DGIV/UMMU) the Skycrane and Dauphin are both invisible. The "old" Skycrane seems to work fine, but the modified version only gives me the generic cockpit (with no fuel or controls) and no visible mesh. The "original" Dauphin has never worked for me in Orbiter '10.

This is using the default graphics client BTW. I've had a similar situation years ago, but I've racked my brain (and the search function) but can't for the life of me remember the cause.

 

[Mythos]

I just tried the dolphin(edit: the dolphin1.zip). Very nice to have some variations of heli to fly :thumbup:

Flight characteristics seem to be still the same. I can't see if K is pressed unless I use some MFD that shows max hover thrust. One would expect to see rotors starting. I easyly reached 500 m/s vertical speed and got to 50k alt.

HoverMFD works great with it.

Yes it can control vertical speed and altitude very well. But if I want to use navigation it oversteers heading and pitch very much. I could make a vessel specific config file for HoverMFD and test a whole day what parameters would be good for pitch and heading adjustment, but that work makes sense only after final versions of your helis are released.
I have to admit that the control of rotation, heading especially, in HoverMFD is not that good calculated by vessel dependencies like VS is. But it's not that bad and same parameters work for any DG-class vessel. So if one vessel or heli doesn't work I indent to say "it's not well balanced".

Here is one funny picture of the dolphin, that is controlling ALT by HoverMFD very well but the attempt to reach a desired landing pad by pitch control got out of control and ended in flying backwards with 600 m/s just 10m over sea level. Seems to get hot enough for reentry flames :lol:

 

[gattispilot]

weird. Reduced the RSC. If I just apply hover then then ceiling is around 4500. Not sure why the meshes are not showing up?

You should only get Hover and rotors if K is pressed.

 

[PhantomCruiser]

Me either. I just tried again on a "ultra clean" installation, no add-ons at all except the Dauphin (not even sound). I'm stumped.