Author Topic: A request for help with mission design problem  (Read 1600 times)

Offline Stalwart

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A request for help with mission design problem
« on: October 05, 2009, 11:53:49 PM »
Hi guys.  I'm really stuck on a problem in my mission design, and I'm all chewed up with FAIL.

I'm building a rather complex project with multiple mission components.  The goal of one mission is to deliver to the combat area a pair of fighters every two minutes, for twenty minutes.  

I have a complete working prototype route and segments for my first flight:
  • taxi, takeoff, cruise and warp to combat area
  • a 20 minute clover leaf attack pattern at the combat area
  • warp back to base landing pattern

Now I want to repeat the same flight plan nine more times, at two minute intervals.

How would you ME vets approach this problem?

 :salute
Stalwart

Offline Baumer

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Re: A request for help with mission design problem
« Reply #1 on: October 06, 2009, 01:34:15 AM »
stalwart, I'll work on this tomorrow morning and get back to you.
HTC Please show the blue planes some love!
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Offline Stalwart

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Re: A request for help with mission design problem
« Reply #2 on: October 06, 2009, 12:34:48 PM »
The file "lambs.zip" contains the prototype and four attempts to solve this mission problem.

http://longhornloftbeds.com/missions/lambs.zip

  • lambs_00.mis: prototype mission, one route, one flight
  • lambs_01.mis: one route, ten flights, roll delay for each flight
  • lambs_02.mis: ten routes, one flight each, roll delay for each flight
  • lambs_03.mis: ten routes, one flight each, 2 minute box pattern taxi segments
  • lambs_04.mis: ten routes, one flight each, 2 minute box pattern cruise segments

In each attempt something unexpected happens.

  • lambs_01.mis: Mixed results.  At first I thought this worked.  Now I'm not so sure.
  • lambs_02.mis: The flights arrive at the combat area much later than expected.
  • lambs_03.mis: The second flight fails to follow the taxi pattern, but all the others flights do.
  • lambs_04.mis: The flights follow the cruise pattern, but arrive much sooner than expected.

Offline Baumer

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Re: A request for help with mission design problem
« Reply #3 on: October 06, 2009, 04:13:32 PM »
Still working on it Stalwart, I've got it working fine in the ME but for some reason I'm having issues actually flying it in the game.

I haven't looked at your files yet but one question I have for you is this, in the ME when you used the rolldelay did you run the mission in the ME?

Did you zoom in and see that the blue cross for the plane was matched up with the white cross for where it's supposed to be?

An important aspect that I just wanted to make sure is clear is that the speed you assign in a segment is the IAS (speed the needle is pointed at) not the TAS (red mark on MPH). So as you go higher you need to set a speed that the plane can actually fly (even in a warp segment) if the white X gets to far in front of the blue X the planes will not behave correctly. Sorry if you know all this, I just wanted to be sure.
HTC Please show the blue planes some love!
F4F-4, FM2, SBD-5, TBM-3

Offline Stalwart

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Re: A request for help with mission design problem
« Reply #4 on: October 06, 2009, 05:24:42 PM »
Still working on it Stalwart, I've got it working fine in the ME but for some reason I'm having issues actually flying it in the game.

Roger.  Let's compare notes on the "weird" stuff.

I haven't looked at your files yet but one question I have for you is this, in the ME when you used the rolldelay did you run the mission in the ME?

Always, and with a stopwatch in hand.  Also ran the missions in-game in offline practice to confirm observations.  Believe it or not, the lamb_01.mis as published works.  If you add roll delay to the first flight in the route, the whole thing falls apart.  (see lamb_02.mis)

Did you zoom in and see that the blue cross for the plane was matched up with the white cross for where it's supposed to be?

Yes, I'm not pushing the envelope with these planes and segments.  I'm using the Spit I and 180 to 200 mph segments, and very little elevation changes.

Interesting note though.  Watch where the white cross goes when you use roll delay.  It explains why roll-delayed flights diverge from the flight plan and seem to meander around.  The flights are seeking out that white cross which has moved way off course.  In some cases, like the 9th and 10th flights, the white cross is 20+ miles off course. (see lamb_01.mis and lamb_02.mis)

An important aspect that I just wanted to make sure is clear is that the speed you assign in a segment is the IAS (speed the needle is pointed at) not the TAS (red mark on MPH). So as you go higher you need to set a speed that the plane can actually fly (even in a warp segment) if the white X gets to far in front of the blue X the planes will not behave correctly. Sorry if you know all this, I just wanted to be sure.

IAS: Indicated Air Speed
TAS:  ? Air Speed

I'm not sure I understand the IAS vs TAS issue, but I don't think I'm flying these planes outside their envelope. 

However: Here's what I saw that I don't understand.  Four way points and segments are laid out to make a square 1.5 miles per leg.  The segment speeds are set to 180 mph at 2000 feet.  The ME calculates these to 30 seconds per segment.  When the mission runs, the square pattern is flown in only 101 seconds, not the expected 120 seconds.  Is this related to IAS vs TAS?  Please help me understand.  (see lamb_04.mis)



Another note:  Building a taxi pattern that merges onto itself seems to create buggy issues.  For example, create an exact square taxi pattern.  Set each leg to .0833 miles which calculates to 30 seconds per leg at 10 mph.  Add another segment after the square pattern to taxi into position for takeoff.  When you run this test in the ME.  The flight might just skip the entire box pattern and taxi straight to the takeoff segment.  (see lamb_03.mis)


I know I'm throwing out a lot of potentially confusing information.  I wish I was in the office so you could look over my shoulder at what I'm doing and see what I'm seeing.

 :salute
Stalwart

Offline Stalwart

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Re: A request for help with mission design problem
« Reply #5 on: October 06, 2009, 05:53:31 PM »
Roll Delay case study: lamb_01.mis variants.

Original Lambs_01.mis: one route, ten flights, roll delay for each flight

Variants:

  • lamb_01a.mis:  Parallel Bishop and Knight missions - WORKS
  • lamb_01b.mis:  Staggered the Bishop and Knight flight roll delays - WORKS
  • lamb_01c.mis:  Added roll delay to the first flight in each route: - FAIL

http://longhornloftbeds.com/missions/lamb_01abc.zip

Adding roll delay to the first flight in a route seems to mess up the the flight plan and timing for all the flights in the route.

Next, I'm going to create lamb_01d.mis which will be exactly like lamb_01a.mis, except the mission briefing time will be bumped from 5 to 65 seconds for the Knights mission and from 5 to 125 seconds for the Bishops mission.

Offline Baumer

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Re: A request for help with mission design problem
« Reply #6 on: October 06, 2009, 06:16:04 PM »
Stalwart you are correct IAS = Indicated Air Speed, TAS = True Air Speed 

This is usually not an issue at low altitude, but as you climb in altitude air density decreases, so the speed that's indicated on the aircraft instrument is actually lower then the speed the plane is actually traveling.

The reason the boxed taxi route doesn't work (I believe need to confirm this with HTC) is that the planes will always seek the next higher waypoint. So if it's closer to the next higher waypoint it will go that way rather than follow the route.

Try this, load this .mis file on your system and open it in the ME.

http://332nd.org/dogs/baumer/Missions/stalwart2.zip

In the mission editor run the mission and follow the Hurri IIC's if you time from the pass of 1 set of Bf109's to the next you will see exactly 60 seconds between them. There is actually a 2 minute delay between them but the 109's and the hurri's are both going 200 mph which cuts the merge time in half.

Don't worry about how the Bf109's look on the ground just fly from the Hurri's view.
HTC Please show the blue planes some love!
F4F-4, FM2, SBD-5, TBM-3

Offline Stalwart

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Re: A request for help with mission design problem
« Reply #7 on: October 06, 2009, 09:42:22 PM »
Your mission works.  :salute

The biggest surprise is how the roll delayed 109 flights behave after the takeoff segment.  They go immediately through the warp segments and line up on the regular cruise segment spaced in proper intervals.  :aok

My designs don't warp directly following the takeoff segment.  Is that why they act so weird?   :uhoh

Baumer, If you don't look at any other files, please look at lamb_01.mis.  It's the closest to stalwart2.mis.  The main difference is that the lamb_01.mis routes have a cruise segment between the takeoff and cruise warp segments.

Thanks Again,
Stalwart
« Last Edit: October 06, 2009, 09:44:28 PM by Stalwart »

Offline Stalwart

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Re: A request for help with mission design problem
« Reply #8 on: October 06, 2009, 11:22:40 PM »
My designs don't warp directly following the takeoff segment.  Is that why they act so weird?   :uhoh

Yes.  Remove the regular cruise segment between takeoff and warp segments, and the problem of the meandering flights goes away.

Offline Stalwart

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Re: A request for help with mission design problem
« Reply #9 on: October 06, 2009, 11:29:08 PM »
Next, I'm going to create lamb_01d.mis which will be exactly like lamb_01a.mis, except the mission briefing time will be bumped from 5 to 65 seconds for the Knights mission and from 5 to 125 seconds for the Bishops mission.

This works too. 

If you intend to delay the initiation of the first flight on a route, extending the briefing time works even better than roll delay.

Offline Baumer

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Re: A request for help with mission design problem
« Reply #10 on: October 07, 2009, 08:26:13 AM »
I'll look at that one Stalwart, and I don't see why having a non warp cruise segment would cause a problem but I will look at that as well.
HTC Please show the blue planes some love!
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Offline Stalwart

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Re: A request for help with mission design problem
« Reply #11 on: October 07, 2009, 11:45:24 PM »
I don't see why having a non warp cruise segment would cause a problem...

When you have:
- multiple flights in a route
- additional roll delay for each flight
- a takeoff segment, followed by a non-warp cruise segment, followed by a warp segment

The flights will leave the flight path after the takeoff segment.  The little white crosses that the flights follow will move back behind the warp segment, far away from the flights.  The flights turn away from the flight path and begin to back track toward the little white crosses.

Here's one more example: http://longhornloftbeds.com/missions/confirm.zip