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SH-60B Development

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Re: SH-60B Development

Postby Philosopher » Mon Aug 26, 2013 3:42 am

Hm, something's messed up with the FDM/Model relationship (coordinates-wise). To get the gear to match the model, these coordinates must be used:
Code: Select all
  <!-- left gear -->
  <gear x="2.00" y="1.343" z="-2.958"
        compression="0.1"
        spring="3.2"
        damp="1.0"
        sfric="1.5"
        dfric="0.8"
        initial-load="1">
        <control-input axis="/controls/gear/brake-left" control="BRAKE"/>
        <control-input axis="/controls/gear/brake-parking" control="BRAKE"/>
        <control-input axis="/controls/gear/gear-down" control="EXTEND"/>
        <control-output control="EXTEND" prop="/gear/gear[1]/position-norm"/>
        <control-speed control="EXTEND" transition-time="7"/>
  </gear>

  <!-- right gear -->
  <gear x="2.00" y="-1.343" z="-2.958"
        compression="0.1"
        spring="3.2"
        damp="1.0"
        sfric="1.5"
        dfric="0.8"
        initial-load="1">
        <control-input axis="/controls/gear/brake-right" control="BRAKE"/>
        <control-input axis="/controls/gear/brake-parking" control="BRAKE"/>
        <control-input axis="/controls/gear/gear-down" control="EXTEND"/>
        <control-output control="EXTEND" prop="/gear/gear[2]/position-norm"/>
        <control-speed control="EXTEND" transition-time="7"/>
  </gear>

  <!-- rear gear -->
  <gear x="-3.344" y="0" z="-2.695"
        compression="0.1"
        spring="3"
        damp="1.0"
        sfric="1.5"
        dfric="0.8">
        <control-input axis="/controls/flight/rudder" control="STEER" square="true" src0="-1" dst0="0.5" src1="1" dst1="-0.5"/>
        <control-output control="STEER" prop="controls/gear/steering"/>
        <control-input axis="/controls/gear/gear-down" control="EXTEND"/>
        <control-output control="EXTEND" prop="/gear/gear[0]/position-norm"/>
        <control-speed control="EXTEND" transition-time="7"/>
  </gear>

This has the x position (front/back) of the front gear as 2.0 and the rear as -3.3. This causes a problem: the rotor is at 2.4 - in front of where the gear matches the model! This means that the model is significantly aft of the FDM (if the FDM even matches up...). I'll go and see if the YASim viewer has anything to say...

EDIT: the YASim importer doesn't seem to be working, but the other option is to change the offsets/x-m in the model.xml to -1.1... The tip of the nose doesn't seem to match then (test by full forward stick and about half-collective, and see where the helicopter rests at), so I'm wondering if the FDM doesn't quite match up.
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Re: SH-60B Development

Postby x7cusick8x » Mon Aug 26, 2013 12:13 pm

The FDM has been updated and will be available in the next release thank you to philosopher for all of your help the Door animation is also fixed.

Im hoping that the V 1.1 will have a rewritten FDM (using the current one as a Code Template) instead of the donor one in this version currently out( Hence nothing lining up in the FDM viewer in Blender). The reason i used a donor FDM is Im learning how to write them as I go along and all the help is appreciated.
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Re: SH-60B Development

Postby x7cusick8x » Mon Aug 26, 2013 5:30 pm

Philosopher wrote in Mon Aug 26, 2013 3:22 am:[*] When the door is fully back, it intersects the pylon-foil thingy, which I don't think is an intentional design feature?

Image
Image
that was actually intentional the door on the actual aircraft has a place for the pylon to slide into i just decided to not cut that out in the model seemed to be too much effort with minimal return
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Re: SH-60B Development

Postby Philosopher » Wed Aug 28, 2013 2:36 am

Okay, here's my work on the landing gear. Model.xml:
Code: Select all
  <!-- Compression -->
  <animation>
    <name>StrutLeft</name>
    <object-name>Main-Strut-L</object-name>
    <object-name>Jack-L</object-name>
  </animation>
  <animation>
    <name>StrutRight</name>
    <object-name>Main-Strut-R</object-name>
    <object-name>Jack-R</object-name>
  </animation>
  <animation>
    <name>Strut-Up</name>
    <object-name>Wheel-Stbd</object-name>
    <object-name>Hub</object-name>
  </animation>

<!-- V 2.11+ ONLY
  <animation>
    <type>rotate</type>
    <object-name>Main-Strut-L</object-name>
    <object-name>Hub-L</object-name>
    <object-name>Wheel-L</object-name>
    <property>/gear/gear[1]/compression-norm</property>
    <interpolation>
      <entry><ind> 0   </ind><dep>  0 </dep></entry>
      <entry><ind> 0.3 </ind><dep> 10 </dep></entry>
      <entry><ind> 1   </ind><dep> 25 </dep></entry>
    </interpolation>
    <center>
      <x-m> -5.292 </x-m>
      <y-m> -1.161 </y-m>
      <z-m> -1.388 </z-m>
    </center>
    <axis>
      <x>  0.000 </x>
      <y> -1.000 </y>
      <z>  0.000 </z>
    </axis>
  </animation>
  <animation>
    <type>locked-track</type>
    <object-name>Jack-L</object-name>
    <center>
      <x-m>-4.319</x-m>
      <y-m>-1.091</y-m>
      <z-m>-1.131</z-m>
    </center>
    <lock-axis>
      <x>0</x>
      <y>1</y>
      <z>0</z>
    </lock-axis>
    <track-axis>
      <x>-0.181</x>
      <y>0</y>
      <z>-0.835</z>
    </track-axis>

    <target-name>Main-Strut-L</target-name>
    <target-center>
      <x-m>-4.500</x-m>
      <y-m>-1.064</y-m>
      <z-m>-1.966</z-m>
    </target-center>
  </animation>
-->
<!-- Replacement code: -->
  <animation>
    <type>rotate</type>
    <object-name>StrutLeft</object-name>
    <object-name>Hub-L</object-name>
    <object-name>Wheel-L</object-name>
    <property>/gear/gear[1]/compression-norm</property>
    <interpolation>
      <entry><ind> 0   </ind><dep>  0 </dep></entry>
      <entry><ind> 0.3 </ind><dep> 10 </dep></entry>
      <entry><ind> 1   </ind><dep> 25 </dep></entry>
    </interpolation>
    <center>
      <x-m> -5.292 </x-m>
      <y-m> -1.161 </y-m>
      <z-m> -1.388 </z-m>
    </center>
    <axis>
      <x>  0.000 </x>
      <y> -1.000 </y>
      <z>  0.000 </z>
    </axis>
  </animation>

  <animation>
    <type>rotate</type>
    <object-name>StrutRight</object-name>
    <object-name>Hub-R</object-name>
    <object-name>Wheel-R</object-name>
    <property>/gear/gear[0]/compression-norm</property>
    <interpolation>
      <entry><ind> 0   </ind><dep>  0 </dep></entry>
      <entry><ind> 0.3 </ind><dep> 10 </dep></entry>
      <entry><ind> 1   </ind><dep> 25 </dep></entry>
    </interpolation>
    <center>
      <x-m> -5.292 </x-m>
      <y-m>  1.161 </y-m>
      <z-m> -1.388 </z-m>
    </center>
    <axis>
      <x>  0.000 </x>
      <y> -1.000 </y>
      <z>  0.000 </z>
    </axis>
  </animation>

  <animation>
    <type>translate</type>
    <object-name>Strut-Up</object-name>
    <property>/gear/gear[2]/compression-norm</property>
    <interpolation>
      <entry><ind> 0 </ind><dep> -0.62 </dep></entry>
      <entry><ind> 1 </ind><dep>  0.0 </dep></entry>
    </interpolation>
     <axis>
       <x>  0.000 </x>
       <y>  0.000 </y>
       <z>  1.000 </z>
     </axis>
  </animation>

FDM:
Code: Select all
  <!-- left gear -->
  <gear x="4.59113" y="-1.4153" z="-2.38"
        compression="0.2"
        spring="3.2"
        damp="1.0"
        sfric="1.5"
        dfric="0.8">
        <control-input axis="/controls/gear/brake-left" control="BRAKE"/>
        <control-input axis="/controls/gear/brake-parking" control="BRAKE"/>
        <control-input axis="/controls/gear/gear-down" control="EXTEND"/>
        <control-output control="EXTEND" prop="/gear/gear[1]/position-norm"/>
        <control-speed control="EXTEND" transition-time="7"/>
  </gear>

  <!-- right gear -->
  <gear x="4.59113" y="1.52786" z="-2.38"
        compression="0.2"
        spring="3.2"
        damp="1.0"
        sfric="1.5"
        dfric="0.8">
        <control-input axis="/controls/gear/brake-right" control="BRAKE"/>
        <control-input axis="/controls/gear/brake-parking" control="BRAKE"/>
        <control-input axis="/controls/gear/gear-down" control="EXTEND"/>
        <control-output control="EXTEND" prop="/gear/gear[2]/position-norm"/>
        <control-speed control="EXTEND" transition-time="7"/>
  </gear>

  <!-- tail gear -->
  <gear x="-0.6688" y="0.04078" z="-2.78"
        compression="0.62"
        spring="3.5"
        damp="1.0"
        sfric="1.5"
        dfric="0.8">
        <control-input axis="/controls/flight/rudder" control="STEER" square="true" src0="-1" dst0="-1.0" src1="1" dst1="1.0"/>
        <control-output control="STEER" prop="controls/gear/steering"/>
        <control-input axis="/controls/gear/gear-down" control="EXTEND"/>
        <control-output control="EXTEND" prop="/gear/gear[0]/position-norm"/>
        <control-speed control="EXTEND" transition-time="7"/>
  </gear>

Like I alluded to in my post in the FDM forum, the tail gear currently has some issues (so keep a backup, or better: use Git), and I wouldn't claim it's very good, just better. The next step is separating the oleos into moving parts, doing scissors, etc., but like I said, that should happen after the release so that you can use the tracking animation as well (I fixed the link, it didn't like the www prefix).

For water effects, I would use submodels and IIRC one can have images (simple textured planes in .ac format) that can grow with time, so I was thinking of a simple white texture that would be on the water. But that's really bad ;), I'm also wondering if that is something that a shader could do better? This is an illustrative photo (also need that vapor on the edges):

Image
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Re: SH-60B Development

Postby x7cusick8x » Wed Aug 28, 2013 2:55 am

Like i said i have an old copy of the model with the separated rear gear so dont worry about cutting them dont want you to waste your time :)
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Re: SH-60B Development

Postby x7cusick8x » Fri Aug 30, 2013 4:28 pm

I am happy to announce that the NEW FDM IS DONE!!!
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Re: SH-60B Development

Postby x7cusick8x » Sun Sep 01, 2013 3:02 am

Sounds are done!

Image
(Location: off the coast of Kuwait, USS Carl Vinson battle group CG-57 USS Lake Champlain)

Running some tricky landings at sea
Last edited by Gijs on Sun Sep 01, 2013 7:22 am, edited 1 time in total.
Reason: Please edit your post if you forgot to add something.
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Re: SH-60B Development

Postby x7cusick8x » Mon Sep 02, 2013 3:31 am

Began work on the particle system im using the MBB BK117 Particle .XML as a template to start hopefully i can single out the carrier deck to not have particles or at least low particle size and number
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Re: SH-60B Development

Postby x7cusick8x » Mon Sep 02, 2013 2:11 pm

Image

Initial particle test
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Re: SH-60B Development

Postby Johan G » Mon Sep 02, 2013 7:02 pm

That looks about right. :D

Looking at helis hovering right above the sea (or the desert) makes me appreciate the robustness of modern turboshaft engines. Just think of all that corrosive salt water spray, sand particles etc. :)
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Some YouTube videos
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Re: SH-60B Development

Postby Philosopher » Tue Sep 03, 2013 2:02 am

Okay, I just got back from vacation, some comments:
  • Steering is reversed :shock:.
  • Framerate drops to 1/3 over here, 20 vs 60 depending on where I look – the funny thing is that it seems to happen when looking straight forward in any view, but changing the heading usually fixes it (the actual amount of heading change required varies with the view). I don't think we have any resources for optimizing models anywhere, though...
  • The copilot doesn't hide when in copilot view.
  • Cleaner code for pushback FDM, I wish there was a better way to do this:
    Code: Select all
      <thruster  x="-0.70346" y="0.06922" z="-1.94395" vx="1" vy="0" vz="0" thrust="600">
       <control-input axis="/sim/model/pushback/target-speed-fps" control="THROTTLE"/>
      </thruster>
  • You don't need to list yourself twice in the <author> tag ;): <author>Reagan Thomas, Maik Justus, James J. Cusick (FDM &amp; 3D)</author>.
  • I still think there's too much collective as it seems to leap off of the ground too quickly, +-40 is what I prefer – even with full load (17540 lbs) it works well. Otherwise, it handles really nicely, awesome work! I'll look at it some more tomorrow :D
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Re: SH-60B Development

Postby x7cusick8x » Tue Sep 03, 2013 2:16 am

Philosopher wrote in Tue Sep 03, 2013 2:02 am:Okay, I just got back from vacation, some comments:
  • Steering is reversed :shock:.
  • Framerate drops to 1/3 over here, 20 vs 60 depending on where I look – the funny thing is that it seems to happen when looking straight forward in any view, but changing the heading usually fixes it (the actual amount of heading change required varies with the view). I don't think we have any resources for optimizing models anywhere, though...
  • The copilot doesn't hide when in copilot view.
  • Cleaner code for pushback FDM, I wish there was a better way to do this:
    Code: Select all
      <thruster  x="-0.70346" y="0.06922" z="-1.94395" vx="1" vy="0" vz="0" thrust="600">
       <control-input axis="/sim/model/pushback/target-speed-fps" control="THROTTLE"/>
      </thruster>
  • You don't need to list yourself twice in the <author> tag ;): <author>Reagan Thomas, Maik Justus, James J. Cusick (FDM &amp; 3D)</author>.
  • I still think there's too much collective as it seems to leap off of the ground too quickly, +-40 is what I prefer – even with full load (17540 lbs) it works well. Otherwise, it handles really nicely, awesome work! I'll look at it some more tomorrow :D


Hahaha i thought something was strange with the steering but i guess thats what happens when you work with an FDM for this long.
I dont know about the frame rate... maybe remove the interior and create an XML for it.
Yah i knew about the copilot and I dont know how to fix that in my attempts the copilot remains invisible in any view.
Yah the pushback is hard because of the tail gear but 600lbs of thrust feels too low on a carrier deck with the pitching of the vessel .
lol ill take that out.
im not sure about the collective, i have no hard data so ill trust you on that one.
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Re: SH-60B Development

Postby x7cusick8x » Tue Sep 03, 2013 7:53 pm

Think i fixed the steering issue in the FDM
Found more flight data so more tweaks to the FDM are on there way

AFCS(automatic flight control system) that is installed on the UH-60 may make an appearance in V1.2 need to see if it (or a variation of it) is installed on the SH-60 Bravo
More to come!
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Re: SH-60B Development

Postby x7cusick8x » Mon Sep 09, 2013 10:11 pm

AFCS has been installed in the SH-60 bravo
System includes:
Auto-hover
SAS
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Re: SH-60B Development

Postby x7cusick8x » Tue Sep 10, 2013 1:49 am

Just integrated the Mule pushback into the SH-60 Bravo aircraft folder to simplify install
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