[dougkeenan]

I made a tutorial page to (hopefully!) help pilots using

AGMFD

AGMFD

.

[dougkeenan]

Egads a major bug, doesn't work with the XR2. I can fix the parameters resetting but it seems to protect its tank from auto-filling. Don't know what I can do about that.

[Gadfly]

Hello Doug:

I haven't found anything about this issue in the documentation for AGMFD: if I shut down Orbiter, when I return AGMFD isn't fully operational. The hold modes seem to work, and I can input acceleration via the set button, but the graphic representation of the course is gone and so, it seems, is the original data displayed on the MFD. Am I missing something or is this just the way the current version operates?

Also: this is easy for me to say, but wouldn't it be nifty if Orrery could interface in some way with AGMFD to function as an ephemeris, which would compute courses allowing for proper "lead" of the target? Then we would be zipping around Heinlein-torchship style, without the curvy homing course!

I think AGMFD is great, and hope you will continue developing it.

Richard

[dougkeenan]

No you're not missing anything, it's my fault. AGMFD doesn't store any information since I didn't know how to code that at the time. That's priority #1 for the next version after correcting a few bugs. It also needs to work for non-Sol systems and other moons, and I'd like to improve the pass-by portion of the course so it doesn't "stutter" like it does.

I like your feature suggestion integrating Orrery a lot. (It more or less fell out of the AGMFD anyway!) I'll have to look into how MFD's "talk" to each other, I haven't done that before. Please let me know if you think of anything else!

[Linguofreak]

Originally Posted by dougkeenan

 Egads a major bug, doesn't work with the XR2. I can fix the parameters resetting but it seems to protect its tank from auto-filling. Don't know what I can do about that.

Yes, the XR series prevents any filling of the tank except through its own fuel hatch. However, I believe this can be disabled in the preference file for the XR craft in question.

[Gadfly]

Doug:

>Perhaps an automated mode, which would compute and handle turnover, target tracking to orbital insertion point--but I think it would be essential to retain full-manual mode as well.

>How about ability to have more than one ship operating with the program in the same scenario, and ability to enter a different ship during the scenario (maybe one can do this now--I don't think I've tried) along the lines of Lola MFD?

>Toggle tank refilling on/off?

>A virtual sextant so you can manually measure angles and compute your own course?

I think a brachistochrone or near-brachistochrone trajectory navigation suite is what you're heading toward here--which is overdue, in my opinion.

Despite my (again, easy for me to propose) list above, I would suggest one of the drivers be relative simplicity for the user. Some of the current navigation tools are very cool, but end up being a bit on the baroque side with all of the features.

I'll send along other ideas if/when I think of them--

R

[dougkeenan]

Something almost ready, v1.49f. It supports multiship, won't CTD on multiple instances, includes moon travel, and I'm polishing up the save/restore. MOD switch cycles to a diagnostic page summarizing ships and system and exposing other controls. Moons (except Luna) are enabled using the PLO (planets only) switch on the diagnostic page, the default is off.

The display has more status indicators and a "complete" field to help manage the transition. (Anywhere from 45% to 55% depending on source and target.) The step size can be adjusted with 'Q' (more steps) and 'W' (less steps). This can help frame rates a bit when climbing out of stronger gravity fields or handling time compression.

Autofill is disabled with 'F' or using a button on the diag page.

[dougkeenan]

v1.5 released at OH

here

here

[flaugher]

Doug, almost a month since the last post here. Any more work on AGMFD? I'm really getting into this 1-G thing, thinking that this could be the ticket for someday breaking space travel wide open. I understand NASA can already do 1 or 2 m/s/s with ion engines, so aren't we saying that this is a science which is actually on the way?

I'm not holding out much hope for Star Trek warp ships, at least in our lifetimes, since high-G travel will probably be hard to break. But doesn't constant 1-G travel seems at least plausible? Wouldn't the public be inspired if Mars were only 4 days away and we could be at the moons of Jupiter and Saturn within weeks? Why, it might even spring loose some funding! Back to the heady days of Mercury and Gemini.

Oh, and I'd love to be able to drink Tang from a glass on my way to Io.

[dougkeenan]

"More work...?" Heck no - I just put v1.5 to bed!

Sure 1-G sounds plausible, though we'll probably work out G/6 travel back and forth to the moon first. That's got to be an enormous savings in fuel for a fledgling technology. I suppose the math is straightforward though I've never calculated it.

Hmm, go get a cookie and let me make a run.

eta: I undocked the standard DG from ISS and made two runs, one at 1-G and one at 1/6-G.

At 1-G it took 3 (almost 4) tanks and about 5 hours. At G/6 it took almost 2 tanks and a bit over 8 hours. (Note: it took over half a tank to climb out of Earth's gravity - I staged the trip at 9.8 until AGMFD could "take over" at the reduced thrust.) That lower deceleration was smooooth though, quite enjoyable. Allows a pilot to gently drop their PeA for an easy approach.

[Andy44]

At just 1/1000 G you can go Earth-Mars-Earth in about 145 days (thanks to R.A. Heinlein for doing the math, see Expanded Universe).

I don't think we can generate that kind of acceleration yet using electric propulsion, can we? Heinlein seemed to think we would be at 1/100 G decades ago, but it never happened. If we can, sign me up!

[dougkeenan]

Thanks to Heinlein for many things.

Might be nice to have the thrust slowly adjust from source to target also, to acclimate passengers.

[flaugher]

I asked this question some time ago. Could we not maintain 1G in orbit by choosing the proper altitude and thrusting to keep position? I guess I'm just one who doesn't' want to live inside a spinning top.

[Andy44]

Originally Posted by flaugher

 I asked this question some time ago. Could we not maintain 1G in orbit by choosing the proper altitude and thrusting to keep position? I guess I'm just one who doesn't' want to live inside a spinning top.

Sure, with a chemical rocket. And you'll run out of fuel in about 5-10 minutes, max. A little more time with a nuclear-thermal rocket. All other propulsion systems we've developed to date cannot generate enough thrust to get anywhere near 1 G.

[dougkeenan]

Aren't we living on a spinning top - well, ball - now?