OHM PursuitMFD 2016

OrbitHangar

Addon Comments
Joined
Apr 9, 2008
Messages
3,832
Reaction score
13
Points
0

Author: rawash

19-11-2017 : Trim corrected


*******
SUMMARY
*******
This release for the 20160828 Orbiter version was written some month ago.
I release it today, after a brief overview, because it gives some corrections and improvements.


Initially based on the Attitude MFD this MFD offers basic features in orbital attitude control:
   orientation relative to orbital velocity (prograde, retrograde or whatever, TOR & RPM pitch up control) or to a target velocity,
   orientation relative to a target,
   and absolute orientation in ecliptic frame.

There is a docking mode which allows to set the correct orientation between the 2 docks or with the targeted vessel relative velocity.
It can also control the relative distance between the 2 spacecrafts and therefore it allows pseudo autodock (obviously a direct manual input method, not an fully autopilot).

The landing mode can make an autoland on gravitational reference bodies with no atmosphere or tiny atmosphere (ex:Mars), with tailsitting or hovering method (pitch up or pitch down).

Up to 32 spacecrafts can be controlled simultaneously and every spacecraft can have up to 32 instances of PursuitMFD running in the same time.
Be aware that closing or changing the mfd WON'T stop the attitude control. To do so you will have to toogle off manually the Hold mode (directly or in the Summary page).
To stop the background calculations, you will have to delete the spacecraft from the list in the Summary page (except the focus vessel).

It should works fine with most of the vessels (I haven't try everyone...).


!!!!!! IMPORTANT !!!!!! :
for a correct control, MFD refresh rate in the Orbiter parameters should not be set too low (0.1 or less is good)
and the maximum acceleration should not be higher than 100x (however limited at some critical phase).

There can be some incompatibilities with scenario saved with previous version of PMFD. just remove the relevant MFD part inside the SCN file.

**************
RECENT CHANGES
**************
Supports Orbiter 2016 elevation modeling of planetary surfaces.
Improvements in attitude control (internal use of quaternions for large attitude changes).
Improvements in landing mode:

   - introduction of 3 decision landing modes with a manual cutoff alitude setting,
   - possibility of autobreak when landed to give full stop on non-flat terrain (Orbiter 2016),
   - new calculation in orbital trajectory prediction for better deorbiting burn time prediction,



DOWNLOAD
 

garyw

O-F Administrator
Administrator
Moderator
Addon Developer
Tutorial Publisher
Joined
May 14, 2008
Messages
10,485
Reaction score
209
Points
138
Location
Kent
Website
blog.gdwnet.com
There is a trim method to position the spacecraft relative to the targeted vessel or dock.

Does that do distance as well as position? That'll be useful for station keeping. Looks like a really good upgrade to attitude MFD.
 

boogabooga

Bug Crusher
Joined
Apr 16, 2011
Messages
2,999
Reaction score
1
Points
0
I've tried it, but I don't quite understand the documentation.

I don't understand the first two trim modes, or what you are supposed to input when you hit shift I.

:shrug:
 

Wolf

Donator
Donator
Joined
Feb 10, 2008
Messages
1,091
Reaction score
11
Points
38
Location
Milan
I have to agree with boogabooga, a more detailed and clear doc would be appreciated
 

Rawash

New member
Joined
Mar 3, 2010
Messages
15
Reaction score
0
Points
0
Sorry for the misunderstanding,

My intention was not to replace totally the very helpful MFD from tblaxland (OK the name i chose is quite confusing), but only to share some tools i wrote to help my flights (dock alignement in particular, and the landing AP was included for testing pupose).
RPM & TOR modes are more immersive and should be used with AttitudeMFD3.


Trim modes are nice for remote control (or lazy days...) but need more explanations, i admit:

1. In trim alignement (one dock not set or set to 0), trim will put your vessel at the distance vector (DST button) from the target vessel (target vessel center reference) and the relative velocity should be close to 0 on final.
It's a kind of station keeping.

2. If HLD or APD is hit in the same time and relative velocity is >0.05m/s, the vessel will orient itself to the target relative velocity, allowing the use of thrusters to zeroing relative velocity. Distance vector is not longer respected. Trim ends automatically.
In fact, this is not so useful (TOR & RPM are more 'graceful'). so you can forget it. I think.

3. When the two docks are set (target dock & user dock), trim will use your thrusters to set the target vessel at the distance defined with DST button from the user dock (user dock reference). It's another station keeping.
Implicitly, a distance vector set at 0 0 0 allows a smooth automatic docking (choose wisely your own waypath before or...:facepalm:).


About distance vector (DST button):
- writing "Xn.n" will change only the x-axis, "Yn.n" only the Y-axis, "Xn.n Yn.n" the X-axis & Y-axis, and so on...
example: writing "x-2.5 z3.7" will change the distance in x to -2.5m & z to 3.7m, leaving y to its former state.
- Leaving a blank distance vector or pressing 'u' in the input will set it to the current distance.




Shift+I is really a cheat code and i mentionned it as a warning.
Any number >0 activate the cheat, escape will cancel.
Personnaly, i use it sometimes to keep ISS in position while i try to dock to it (without AP) because there is no (still) inertia wheels simulated to keep the iss orientation in station during the close approach phase.



The other pages (velocity, relative & global modes) are almost the same as those in Attitude MFD 3.

To use landing AP, just set the target base by using its name or a number.
Setting a pad number is not necessary.



:cheers:
RP.
 
Last edited:

Keatah

Active member
Joined
Apr 14, 2008
Messages
2,218
Reaction score
2
Points
38
If I could use this to adjust the lady's temperament I'd be in spiffy-o dandy shape!
 

Cras

Spring of Life!
Donator
Joined
Apr 13, 2011
Messages
2,215
Reaction score
0
Points
36
Location
Los Angeles
Website
www.youtube.com
Ok, gotcha on where you are coming from on this. I was writting up some procedures on how to get a CTV up to a space station and I see an opportunity to use this for the docking portion, Ill let you know how it works out. The expanded capacity for station keeping I feel is a real strong point here.

Shift+I is really a cheat code and i mentioned it as a warning.
Any number >0 activate the cheat, escape will cancel.
Personally, i use it sometimes to keep ISS in position while i try to dock to it (without AP) because there is no (still) inertia wheels simulated to keep the iss orientation in station during the close approach phase.

There is an addon out there called CMG 2 which essentially does what you seem to be doing, in that it "cheats" itself into an attitude. I have attached it to ISS 3.2, A to Z and even my own station and have used it to maintain attitude for proximity and docking ops. I find docking to a station while the station is just in free drift and orientated any which way to be just plain silly. I suggest you give it a look see, it truly is a fantastic way to keep a space station under control.

I admit I was lead by the title of the MFD that this was to be a new version, replacing the old one, and thus the removal of the RPM and twice orbital functions to be confusing, but looking at it again, I feel your work will compliment the old tried and true Attitude MFD nicely.

Cheers :cheers:
 

Ripley

Tutorial translator
Donator
Joined
Sep 12, 2010
Messages
3,133
Reaction score
407
Points
123
Location
Rome
Website
www.tuttovola.org
...I admit I was lead by the title of the MFD that this was to be a new version, replacing the old one, and thus the removal of the RPM and twice orbital functions to be confusing, but looking at it again, I feel your work will compliment the old tried and true Attitude MFD nicely...
Me too, but why naming it this way??
Apart from the missing blanks ("AttitudeMFD4" Vs. "Attitude MFD V3.2"), I think it IS misleading.
 

n122vu

Addon Developer
Addon Developer
Donator
Joined
Nov 1, 2007
Messages
3,196
Reaction score
51
Points
73
Location
KDCY
Me too, but why naming it this way??
Apart from the missing blanks ("AttitudeMFD4" Vs. "Attitude MFD V3.2"), I think it IS misleading.

I have to agree on this. Calling it "4" just plain suggests its the next version. Maybe "Station Keeping MFD" or "Station Keeping MFD with Landing Mode" would have been a better choice.

:2cents:
 

Keatah

Active member
Joined
Apr 14, 2008
Messages
2,218
Reaction score
2
Points
38
I have to agree on this. Calling it "4" just plain suggests its the next version. Maybe "Station Keeping MFD" or "Station Keeping MFD with Landing Mode" would have been a better choice.

:2cents:

Can't make it too long, or else it won't fit nicely in MFD SELECTION screen.
 

Wishbone

Clueless developer
Addon Developer
Joined
Sep 12, 2010
Messages
2,421
Reaction score
1
Points
0
Location
Moscow
Why don't you call it Anchor MFD?
 

Rawash

New member
Joined
Mar 3, 2010
Messages
15
Reaction score
0
Points
0
New name

AnchorMFD is nice but i choose PursuitMFD.
Why ???
:tiphat:

RG.
 

Wishbone

Clueless developer
Addon Developer
Joined
Sep 12, 2010
Messages
2,421
Reaction score
1
Points
0
Location
Moscow
Tried the sample docking scenario; was very much worried when the DG charged forward a la Progress, relieved at smooth docking. May be of use setting a user-tunable maximum relative speed to avoid breaking ground rules.

EDIT: Landing scenario CTDs without any message in the logs. Suggest adding diagnostic logging to the MFD.
 
Last edited:

boogabooga

Bug Crusher
Joined
Apr 16, 2011
Messages
2,999
Reaction score
1
Points
0
AnchorMFD is nice but i choose PursuitMFD.
Why ???
:tiphat:

RG.

And Ranwash learns an important lesson in marketing. ;)

Actually, now that I understand, it's a pretty nice MFD.:thumbup:
 

Interceptor

Well-known member
Joined
Mar 28, 2008
Messages
2,718
Reaction score
76
Points
63
Location
Michigan,Florida
Hi rawash,this is a wonderful tool,it lands,and docks everything I have tested it with,but one question,I am not great with vectors what would the Distance in XYZ be, stopped about 25 feet in front of the chosen dock,so in other words, how do I enter this in the Dis box?Thanks
 
Last edited:
Top