Realism


#1

Every space game ever invented to date uses clunky mechanics really based on coal age navies. In space every weapon has unlimited range. The effective range of a weapon is based on the respective times it takes to fire and the time it takes the target to dodge. For example a ship that can dodge in 2 seconds will be out of range of lasers at a distance from the earth to the moon, and out of range of a .50 cal machine gun at 2km. A heavier ship with twice as much dodgetime would be vulnerable to all weapons at twice the distance.

The relative velocity of the two fleets is greatly important. A meeting engagement of two fleets at rest is absurd. I would like to see a game where fleets were set up like in GSB. However the fleets would be set very far apart and hurled toward each other at great speed. The two fleets could be hurled through each other and the game would end when all ships had passed out of effective range on the other side. Rather than a dogfight or a slugfest, battle would be more like a joust.

Suppose two fleets collided with a relative velocity of 4% the speed of light. The fleets would be in laser range of each other for a few minutes. Ships could only get within machine gun range of each other for a fraction of a second, but each bullet travelling at 4% c has the power of a Hiroshima bomb. The exact numbers that come out of special relativity are outside of human scale, but the concepts can be brought into a game by using a small number for c and so on…

Suppose a game made it possible to adjust the relative velocity of the fleets, (fast, medium,slow, none;). As you go up in relative velocity the power of massive projectiles increases radically, while beam weapons have the same power at all velocity settings. For example, in fast the fleets might pass 8x the slow speed, and do 64x the damage with mass weapons. At medium speed the fleets would pass at 4x, and do 16x the damage with mass weapons.

In the moments after the fleets pass each other only beam weapons will be effective, and they will have the luxury of picking off the enemy from behind.

In a fast setting, standoffs and platforms would be overpowered. But the ability to detect anything would be low.
At medium, fighters and drones could dish out death with little blasters.
At slow, heavier ships would be somewhat better.
None, would be a slugfest as it is now.

Naturally this sort of scheme would lend itself well to battle in waves, where in the final round all the survivors make a final appearance.


#2

I respectfully disagree. If a fleet is hurtling towards yours, you don’t go all ahead at full speed yourself. You stand where you are (or maybe even reverse) and pour as much fire as you can into the approaching ships. They are essentially not moving as far as your targeting systems are concerned, making them a very easy target. On the other hand, passing by someone at high speed makes it nearly impossible to hit them. It works in big anime robot battles, sure, but that’s not know for its realism generally.

As for weapon ranges, you are sort of correct but not entirely. At extreme range you lose accuracy due to small differences in launch angle resulting in huge differences by the time the projectile reaches the right distance. Think of the “resolution” of the targeting systems. After a certain point you will only hit the target out of sheer luck, at which point you can say they’re effectively out of range.

Old tactics aren’t used because we’re out of date, they’re used because they work :slight_smile:


#3

For me realism starts with Newton’s first law.

The accuracy of weapons at long range is an issue. But the maneuverability of the target is far more important. Generally speaking a target with half the acceleration could be targeted at twice the distance.

Velocity (not to be confused with maneuverability) is not important for targeting or for lasers. However any projectile with mass will increase in power exponentialally with velocity, and of course projectiles carry the initial velocity of their gunners. When you talk about interstellar travel you are talking about initial velocities and initial energies of ridiculous proportions.


#4

Hey, you say that as if it’s somehow a bad thing…


I love this sort of ponderous-slow-battleships-in-your-FACE! combat. And to a large extent, Cliffski agrees with me. :wink:

For me it stops once I boot-up a game whose title starts with the word “Gratuitous” prominently displayed therein.

Seriously, you make superb arguments concerning realism but in a broader conceptual sense, you are absolutely barking up the wrong tree. This isn’t a game for realism. GSB is essentially a space-opera fireworks display set to music.

It also happens to have a vital strategic decision-making prelude that one must navigate before the fireworks truly begin, yes, but in no way is it intended as a “realistic combat sim” or “you need a graphing calculator and a Geiger counter in order to play this game” or somesuch. While i would love to see the overall visual style and ease-of-use in GSB combined with the same sort of hardcore realistic limits, concepts and tactical options that you describe, I doubt it’s ever going to happen. Alas. :slight_smile:


#5

I have to say the Archduke hit this subject on the head with a battleship! And i agree Broadsiding your enemy and watching him sink is much much better than pushing a button to send off a missile to sink the same ship. Boooooaaaarrrrriiinnngggg ! ! ! I want to soooo badly kick the Navy’s in the butt for letting our battleships go to waste like they have. But It is also true that in the Iraqi war there was two Battleships that made the trip over there to shell Baghdad, BUT I do not think we will EVER know about it or they will downplay it. As it cost soooooo much money to have those battle-wagons burn that much oil to get over there and back.

I do wish that Aircraft carriers were NEVER made. Since they came into the scene the old battlewagon Battleships were no longer needed in navy battles anymore.


#6

That’s true if you ignore practical concerns like the ability to actually move your weapon fast enough to track someone who’s moving past at high speed, especially when they’re close in to you.

I am quite interested in where this discussion will go.


#7

Excellent responses. As a game of coal age naval warfare with sci-fi skin, Gratuitous Space Battles definitely rocks harder than Sins of a Solar Empire or Homeworld 2.

One of my favorite books of all time is “Enders Game” by Orson Scott Card. It got me thinking long and hard about warfare in space. Card recognized many key features of war in space. For starters battle in interstellar space or at the edges of a solar system is impractical. Interstellar space is just too darn big. Fortifying the edge of a solar system just doesn’t work because the defenses will orbit the sun over thousands of years and be on the wrong side of the solar system most of the time.

Standoff projectiles from the invader work exactly the same as mines by the defender. At high velocity a BB can pack megatons worth of impact energy. A missile the size of a crow bar could penetrate underground bunkers. A cloud of dust might by very destructive over a wide area. The defender would have similar power with mines, but they would clutter up their own space. Lot of cheap decoy starships is probably the defense of choice.

Because spaceships are not in a fluid, they have no need of hulls. A scaffolding is better than a hull in many regards. A spaceship that was built like a spider web such that >90% of its area was empty space, could dodge by maneuvering the width of its widest members. Segments or modules could be designed to break away when hit, such that megaton hits would blow through and not be absorbed by the rest of the ship.

A simple trade off exists between stealth and laser defense. A black surface that absorbs 99% of the EM radiation that strikes it, and has a low temperature, will be extremely difficult to detect however it will also take all the energy of laser fire and overheat. A silver or polished aluminum surface will reflect 99% of the EM radiation that strikes it, but be very easy to detect. Somebody will obviously try to combine the two with some sort of layering, or some fleets might choose a black bow and a silver tail. Most fleets will probably want to hide as long as possible, and then put on a fireworks show to dazzle the enemy sensors.

Modern militaries are already turning to drones. I have always thought more robots are a no brainer for any space fleet. Including lots of unpiloted vehicles.


#8

Intrastellar warfare is another ball game. The fun thing then is how the planets rotate at different periods. So that Earth and Mars are anywhere between 3 light minutes and 24 light minutes apart, and so on with the rest of the planets and asteroids. There was an old shareware game where all the planets did rotate and you played one spaceship that could fight other spaceships or transport colonists to take over a body.

There is another interesting feature of solar systems that should be exploited. Each planet creates in its wake a series of LaGrangian points. These are stable points in the same orbit as the planets. They are the perfect places to put extra bases, like asteroids and so on.
en.wikipedia.org/wiki/Lagrangian_point


#9

You’ve done your research, I like that. Several people have mentioned Enders Game to me now. I may have to check it out.

Regarding projectiles, you are correct. Without air resistance to slow them down, they can be accelerated to the point that their kinetic energy is huge. There are two requirements to achieve this:

  1. The ability to accelerate the projectile to ludicrous speeds.
  2. The ability for the target to absorb all that energy. The projectile is going to want to make a neat hole straight through, though it gets a whole lot messier once it hits the structure and internal atmosphere. I imagine you’d get the spaceship equivalent of hydrostatic shock. You’d need a big target (like a planet) to properly dump all the energy though.

#10

In order for spaceships to survive any sort of combat, they will need to be able to accelerate at at least one gee. Even if you allow for wormholes or gates to travel interstellar distance (I prefer not to), you still need the acceleration to survive any sort of combat. If they can accelerate one gee continuously, then they can travel to new star systems within a century or so. And attain the ludicrous speeds. In the reference frame of the travelers they will have plenty of time to position standoffs in and around their fleet. The projectiles do not need further acceleration. Any ship that want to have a reasonable chance of stopping in the solar system will begin to decelerate. Realistically then the standoffs might hit decades ahead of the rest of the fleet, which would give the defender time to prepare. Or the invader might save the element of surprise and wait till he gets closer, but then he would pay the cost of decelerating that mass of ammo and hit with less punch.

Stationary defenses are fine as long as they are cheap, plentiful, and hard to detect. It is interesting to think how asteroids and moons could be used as bases. For game purposes it makes sense that moons would be too large to destroy, and while a hit might have an area of effect, you could not destroy all the machines and structures on a moon without hitting it from multiple directions. Asteroids of different sizes would react differently to different size weapons.


#11

No such thing as hard to detect in space man, any heat signature is obvious in the background of 3 degree kelvin.

Besides, nothing is “stationary” in space. Though many do have a fix path making them easy to predict and target. Which strangely also means that any fleet moving with extreme forward momentum are easier to hit, because under Newton’s second law they can’t exactly turn to avoid anything.


#12

Empty space does not have temperature. A speck of dust in intergalactic space would be 3 degrees kelvin. In interstellar space the dust is a bit warmer than that, and in intrastellar space it is warmer still. The Kuiper belt objects seem to be 50-33 degrees kelvin. The Kuiper belt is full of large objects which have not been detected yet. We found several new dwarf planets in the past decade, Sedna and Quaoar. So big things can stay hidden for a long time. The asteroid belt is 150-200 K, and we haven’t identified all the asteroids.

Ideally an invading ship would want to present the coolest face possible to the defenders. One way to do that is with umbrellas. Vectoring thrust directly toward the opponent would generally give away your position, but only if the defender was monitoring closely because until you got very close to the destination solar system all your exhaust would appear to be from your original star. One could also hide exhaust by deploying a giant black plastic tarp ahead of your vessel and letting it get far enough away the exhaust wouldn’t melt the plastic. Another way to hide exhaust is to do a spiral decent deceleration so the exhaust is never pointed directly at enemy sensors, some types of engines can give you much more precise direction for the exhaust.

A ship that has been detected can only survive if it is able to accelerate in any direction a distance greater than its own length in the time it takes a weapon to be fired at it. This ability to accelerate sideways in an unpredictable fashion does not depend on forward velocity, except for the time dilation; and the time dialation is not severe until you get close to the speed of light.


#13

can I just take the time to remind everyone on this forum about the meaning of the term “gratuitous”?


#14

Point well taken, gunnyfreak, though it seems Mangudai is not listening.


#15

How long are firing range, exactly? A few light-days at most? Surely any thrust exhaust/life support system will be exposed well before anything reaches firing range. Anything that shoots in a strait line, including kinetic weapons, lasers, and plasmas, are simply useless in that range. Leaving only tracking missiles, but their exhaust will shine like a Christmas tree.


#16

Range depends on the speed at which targets maneuver. Stationary targets like asteroid bases don’t maneuver at all and therefore can be targeted from light years away. A capital ship that takes 5 minutes to accelerate its own width, would be safe from lasers at interplanetary distances.

Since lasers might not be effective against reflective hulls, our standby weapon is a .50 cal machinegun whose muzzle velocity is 1000m/s. This gun could target the capital ship within 300,000 m because the bullet could travel that distance in 5 minutes before the capital ship could maneuver. At high relative velocity the problem becomes a bit more complicated, the shooter would have a window through which to hit the target. Slow targets would have larger windows than fast targets.

Basically each ship has an attribute called DODGETIME, this is the time it takes to accelerate more than one ship width in any direction. DODGETIME = sqrt(2*width/acceleration).

Every weapon has an attrubute called FIRINGTIME. FIRINGTIME = distance/c + processingtime + distance/projectilevelocity.
Where distance is the distance between the shooter and target, processingtime allows for turret tracking, projectile velocity is what the name implies.

Now take the ratio DODGETIME/FIRINGTIME = TARGETABILITY. As targetability approaches 0 a target becomes unhittable. A targetability of 1 means the target can sidestep one body width exactly. Then we have a question of relative area. Take a grid of nine squares. The target was in the center square, but when the shot reaches the target could be any of the nine squares. So targetability 1 means roughly 1/9 chance of a hit. A disc shaped target with radius r, at targetability 1 would be within a circle of radius 3r, again a 1/9 chance of a hit. However a smart machine gunner will not guess, he will fire 9 bullets and be confident that one would hit. Complicated hull shapes and assymetrical thrusters would complicate things, but since I studied physics I have no problem saying that a cow is approximately a sphere.

1/TARGETABILITY * constant = chance of a miss
so targetability of 10 means only 1 out of 10 shots is likely to miss.

Let me emphasize one more time that the ability of the target to accelerate relative to its own size is critical.

That and the ability to hide. I agree that space is unlike other environments in that sensory equipment is extremely good, and hiding extremely difficult. Life support and thrusters must be warm. On the other hand, I speculate that computers could function fine at temperatures of 50K or colder. So they could run silent until very close.


#17

One minor point - a realistic laser wouldn’t have unlimited range. I’m not sure whether perfect optics are even theoretically possible, but even if they are you’re going to get diffraction from gas and dust in space. In the more likely scenario that our optics aren’t perfect, the beam is going to spread and dump its energy over a larger area.


#18

I can’t imagine shots hitting anything 1 light year away… When something takes over 1 year to reach a target, chaos theory really takes a toll in making things miss. Without thruster to adjust coordinate, even a speck of dust will make it go way out of course. And with thrusters they will be obvious enough for interception.

And consider how much it cost to carry ammo over galaxies, dakka is simply not an option.

In terms of forward momentum, there are a few concepts, such as bias drive and solar sail, that does not generate heat. Hiding the heat from life support system will be nearly impossible though, so robots will probably be the best option in carrying out an assault. Problem is it still needs to hide the power source, and with entropy this is highly improbable.

daviddarling.info/encycloped … cepts.html

I think the best kind of defense in real space battle will not be shield, but EMP emitters and guidance scramblers.


#19

Nice link, thanks. Nasa left mirrors on the surface of the moon and later shined lasers on them. So a few light seconds of accuracy is reasonable. Whether the Earth and Mars could exchange laser fire, I do not know. Anything capable of maneuver should be fine at interplanetary distances. However a target like a planet or moon could be hit from insane distances. To throw an iron bar from the edge of the solar system to a city on Earth is totally reasonable. And an attack like this could hardly be countered by a defense which costs less.

arclight.net/~pdb/hammer-lig … index.html

This site has some interesting information on space weaponry. One weapon it mentions is the “squirt bomb”, also discussed by science fiction writer Larry Niven. The concept is to use a nuclear explosion as a source of gamma rays, and focus them with a cylindrical laser that would be destroyed by the explosion but not before reflecting enough light to get the laser effect. This laser could harness a reasonable fraction of the total warhead energy which might be as much energy as any system could handle without self destructing.

Regarding stealth, I think an invader could do a pretty good job hiding their blackbody radiation simply by using umbrellas that are black facing forward and silver facing the ship with connections which transmit very little heat.