In article <6i05jp$n1...@texas.nwlink.com>,
Pizaz <mi...@nwlink.comNOSPAM> wrote:
>I was wondering if there were any resources out there where i could find
>information on how to design an AI for computer controlled spacecraft,
>specifically for space combat. I really dont know where to start at this
>point. I do know that i want to have accurate physics modeling (with the
>exception that i 'might' ignore gravity wells and limit the scope to strict
>0 g engagements).
First off, you have a whole lot of issues to think about even
before worrying about computer AIs. First figure out the human
side of the equation.
The big thing you have to figure out is the time/space scale.
You should realize that unless you're going to be flying
spacecraft next to black holes or near the surface of
planets, practically any playable realtime outer space game
can completely ignore gravity.
You can pretty much forget about realistic weapons, fuel,
and thrust considerations. The time/space scales of such
things would lead to battles taking hours or days to
finish, and neither side would ever be in visual range of
the other (except through powerful telescopes).
So you'll just have to make up the numbers and go for
There are basically three sorts of weapons with realistic
physics that lead to three sorts of combat maneuvering:
1. "Missiles". These are long range disposable guided
weapons which have superior thrust and delta-v than
their targets, which ram the target and/or use
relatively short range weapons.
These weapons lead to combat maneuvering similar to
current blue water navy ships. Essentially, the
maneuvers of the ships don't matter. It's a battle
of numbers as the "missiles" fly.
2. "Beams". These are multi-shot weapons with a limited
practical range, but with a high "muzzle velocity" so
that the relative velocity with the target doesn't
matter. This includes lasers, particle beams, and
possibly fancy projectile weapons.
These weapons lead to combat maneuvering a little
like WW1 style big gun ship combat. Both sides
try to maneuver their ship(s) to the most favorable
combat range. In a simple duel, the one with
superior longer range firepower will attempt to
keep its distance while the other one will attempt
to close the distance or run away.
With real life physics, these maneuvers will mostly
be one dimensional--only thrusting directly towards
or away from the enemy is relevant, much of the time.
3. "Bombs". These are projectiles which may have
superior thrust, but _inferior_ delta-v than their
targets. They ram the target and/or use short
range weapons to damage the target.
These weapons lead to complex combat maneuvering
which has no terrestrial parallel, although it's
sort of analagous to ancient ship combat mixed
with air combat maneuvering. In order to attack,
the firing ship must either thrust towards the
target to sling its "bombs" toward the target or
wait for the target to thrust towards him. In
order to avoid counterattack, the firing ship
must break off.
In the case of a duel, this leads to two dimensional
maneuvering as both sides dance around each other.
In any other case, extremely complex 3D maneuvers
For playability, either option 2 or a mix of option
2 and 3 is best. While option 1 is arguable most
realistic, it does mean maneuvers are largely irrelevant.
It turns the game into something like Missile Command.
I'd probably go with option 2 alone for an easy to
grasp, game. I'd suggest option 2 with some option
3 weapons for advanced players.
Option 3 alone would lead to an incredible amount
of tactical richness, but most players would be
completely bewildered. The only game I've played which
uses this is the Amiga version of Spacewar. I'm used to
it, and it's very interesting playing against another
skilled player. However, novices are just hopeless.
They just don't understand the implications of having
a low muzzle velocity compared to your thrust. They
think that the typical engagement will be some sort
of "blow-through", but that's a mistake. It would
simply lead to both sides destroying each other, since
neither can hope to get out of the way of the enemy's
fire. The experienced player will simply fire its
torps toward the incoming novice and break off,
avoiding the novice's fire while he rams into the slow
wall of torps.
>What types of rules system should i use. What type of AI
>classification would this fall under? (i.e. state based?)
>Essentially, I need to know what would a real space battle
It depends upon the technology involved. With most
plausible technology assumptions, it would be essentially
very long range and taking place over days, weeks, or
months. So don't worry about that.
>What types of basic combat maneuvers apply in space?
It varies drastically depending upon what sort of
technology is involved. Note that this is an area
in which very few people have seriously thought
things out. For instance, most seem to think that
some sort of "blow through" maneuvers with thrusting
to reengage would be typical. In fact, this would
be a mistake. Under no circumstances will _both_
sides correctly want to reengage. One side is
attempting to stop the other, and the other is
trying to break through. However, the side that
is attempting to stop the other has made a big
mistake if it allows a "blow through" to occur in
the first place and it has the thrust needed to
If it has the thrust needed to reengage after a
blow through, it certainly had enough thrust to
match velocities--and this would require less
fuel. Matching velocities would allow them to
continuously engage the forces trying to break
through until they were destroyed, rather than
getting in some sporadic fire in a couple blow
Of course, with most semi-plausible technology
assumptions, the real result of a "blowthrough"
pass is that both sides are obliterated, even
if one side is greatly inferior to the other.
That makes any possiblity of reengagement moot.
>Under what conditions would should a ship attempt to flee?
>Is fleeing even a feasible option in space combat?
It depends upon the strategic situation, and the
technology involved. Assuming a very simple
strategic situation--this is a simple duel between
two private ships with captains who have a mortal
grudge against each other--a ship should flee
if it faces poor odds. Fleeing is an option,
in the proper circumstances. Typically, a ship
with superior delta-v can flee from a ship with
inferior delta-v and comparable thrust.
(For ships with equal average exhaust velocity and
equal payload mass, the one with more fuel has
>I suppose the only option is to attempt to outrun them?
Not exactly, In space maneuvering, fuel is not a
limit on how far you can go, it's a limit on how
much you can thrust.
>Complicating this are the different types and sizes of ships. For instance,
>fighters will be engaging in close combat while huge Destroyer class
>battleships could probably engage each other from many many miles away
>(especially if they were using lasers and had very accurate targetting
How realistic do you want to be? You should realize that
even a 20mm airplane gun could be very accurately fired
over many miles in space. There isn't any air to mess
with the aim, and no gravity/ground to limit how far the
Now, there are a whole lot of non-intuitive issues with
lasers (in particular, the ways in which they may do
damage), but here's a single number on the matter of
range. The 4m diameter Star Lite high power laser which
has already been fired on the ground has an estimated
practical range in space of more than 5000km (the
actual limit is classified).
>I really need help designing this sytem. Can anyone offer assistance?
Well, thoughts on realistic space combat is a hobby of mine.
_____ Isaac Kuo k...@bit.csc.lsu.edu http://www.csc.lsu.edu/~kuo
/___________\ "Mari-san... Yokatta...
\=\)-----(/=/ ...Yokatta go-buji de..." - Karigari Hiroshi