don't exist "yet". The build them higher every day...and with sufficient amounts of materials a pyramid could be built arbitrarily high. The ancient egyptians built these giant pyramids without steel rebarb reinforced concrete. Nobody builds pyramids because they take up too much real estate on the ground. But in space, who cares. Its these long skinny ships that will have this problem, especially with torque from maneuvering jets. These things sway noticeably in a stiff breeze. Imagine what thrusters will do to them. Like I said, I think that every hull should have a maximum acceleration associated with it based on the constraint of structural integrity, but by devoting some mass and space inside the ship toward structural integrity(which would incidentally make the ship more difficult to destroy and more massive...slowing it down, one should be able to improve the maximum acceleration. This would be rather inefficient though since the structural integrity increases the mass...which means you need more power just to get to where you were before structural integrity upgrade...and then more power to get up to the new maximum. With only so much space for structural integrity modules and thrust production modules and the need to leave some space for cargo. There would be significant tradeoffs for a benefit that can be tweaked as needed (in terms of the numbers) to produce the desired effect. Thus, by making structural integrity expensive in terms of space and mass, making a 5 kilometer ship that accelerates like a lear jet could be made impossible or possible depending on player feedback. This choice, to me, seems to provide the most flexibility for mod developers as well as for this game.chuck_starchaser wrote:Can't. There's a reason why sky-scrapers 20 kilometers high don't exist. They can't be accelerated by the ground against 1G gravity. Same applies to a structure in space. Worse, because buildings on the ground don't sport maneuvering jets.
Well, most of this game is outside our experience but I don't think that it is outside our imaginative capacity. It is not outside the realm of the physically plausible either. A tetrahedron structure (thanks) several kilometers long could probably handle 1g accelerations if it were well reinforced and you allow for advancements in structural engineering without stretching the imagination too much. In terms of game play. It allows a scenario where one ship is the cargo and engines ship. It gets it acceleration high enough that it can keep up with its escorts. Or it gives captains that ferry cargo in relatively safe areas an option to increase their profit margin a little by speeding up the transport of goods (though the benefits of this would be dubious since extra engines and structural integrity would take up space that could have been used as cargo space. As for player assumptions about the size of a ship, I don't see how that is relevant. Information available from the radar or targeting information will tell you the ship's size. And when you see 15 giant thrusters on the back, the output from which obliterates a small interceptor that happened to be flying behind it when the engines ignited, players will understand that this ship is designed for high speed cargo hauling. Another thing to keep in mind here is the benefits of having engines that accelerate at 1G....no need for "artificial gravity". To me, artificial gravity is completely unphysical. There is only one way to get artificial gravity...accelerate at G...either through centrifugal force on a spinning space station or by by having engines that produces thrust 9.8 times the mass of the spaceship. For ships that do extended duty in space without docking, 1g accelerations would be necessary to prevent bone degradation and muscular atrophy. For me anyway, immersiveness is the most critical part of any sim game. My feeling is that 1G should be the standard acceleration for most capital ships(The bigger ones will need more engines and structural integrity reinforcements to do this), with emergency acceleration up to maybe 3Gs. It isn't feasible to go much higher since the crew won't be strapped down in a nice cushioned chair with artificial pumps for blood to continue to flow during 10G acceleration maneuvers...unless you invent magical inertial dampeners as well that have no basis in reality.but even if I'm wrong and we have materials 1000 times stronger in the future, what does that do for us in terms of gameplay? Nothing. Because if you see a 5 kilometer long ship and it accelerates like a lear-jet, you (the player) will simply assume that it is roughly the size of a lear-jet. Why? Because kilometer-sized structures accelerating at multi-G accelerations are totally outside our experience AND imaginative capacity.
Well, I am not saying what the numbers should be, but I think there should be a mechanism built into the engine that allows players to customize their ships to create capital ships with more acceleration than usual if they properly reinforce the hull to handle the stress and have enough thrust. The exact numbers could be determined through player feedback. If the structural integrity cost is too high in terms of mass and volume, then players won't ever buy it, and they will continue to complain at how slow capital ships are and they can't do anything about it.Ditto. Neither kinesthetically believable, nor of any gameplay value; unless you're talking about boosting accel from 0.02 G to 0.023 G, or something like that.
Well, I'm not the lead guy for vegastrike; not sure there is one anymore; but the matter of antimatter was considered a long many years ago, and abandoned for fusion. And I can't say I disagree with the decision. Problem with antimatter is storage, as you probably know already.
Having said that, it once occurred to me that a new "chemistry" might perhaps be conceivable, where matter and antimatter are bonded in a stable fashion and grown into chrystals. It would have to be some matter crystal structure with cavities featuring a lot of negative charges pointing inwards, where a single anti-hydrogen or anti-deuterium nucleus fits suspended.
But anyhow, in the vegastrike universe ships' power comes from fusion; and I once argued we needed a specification for the fusion fuel, but that never happened. I'd argue for Helium 3.
But in any case, what makes it really easy to sweep aside the fuel and propulsion problems is the fact that we have a much bigger problem to solve first: Getting rid of excess heat.
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Well, this one of those rare times when I feel an assumption regarding technical advancements is necessary in order to keep the game realistically plausbile (i.e. don't break any fundamental laws of physics) while still keeping game play fun. Fusion is terribly inefficient in terms of energy per kilogram of fuel(<7*10^14 J/Kg). Even if you neglect the mass of the fusion reactor, you get less than 1% of the rest mass of the reactants liberated in the form of energy. It does provide a convenient propellant though which I will discuss later(the products of the reaction that are not involved in any further fusion reactions). Anti-matter annihilation has a theoretical limit of 9*10^16 J/Kg. That means you need 100 times less fuel to get the same energy output.
Consider a fusion reactor that has fuel equivalent to 1% the mass of the ship. Assume that the 7*10^14 Joules of energy is pumped directly into the roughly kilogram mass of reaction products which then impart all their momentum to the ship...a perfectly efficient process. That gives an exhaust velocity of 3.72e7 m/s. These are mildly relativistic particles so we must use the relativistic rocket equation, but the effective exhaust velocity is 3.75e7. With 1% of the ship as fuel, this gives deltaV=3.76*10^5 m/s...less than the maximum speed of a dostoevsky.
Now consider an anti-matter power plant produces 9*10^16 Joules/Kg with an exhaust velocity of c if it directly utilizes the resulting gamma-rays as propellant. deltaV=3.02*10^6 m/s. While the fusion reactor is more energy efficient in terms of power to thrust ratio by about an order of magnitude, the power/Kg of the anti-matter engine is more efficient by 2 orders of magnitude. This doesn't even include how useful the extra energy efficiency is for weapons and other ship systems.
Furthermore, consider the typical accelerations involved in this game. 10g accelerations. By noting that deltam is small, we can assume the mass (and therefore the acceleration resulting from the thrust) is roughly constant and equate a*t=deltaV to give us a measure of how long you can thrust before running out of fuel. For fusion, roughly 1 hour of 10g acceleration. For anti-matter, 8 hours of 10g acceleration.
Other possibilities include a mass of propellant heated by the energy output of one of the two power plants above that can be used to improve the power to thrust ratio. Essentially, by taking the power generated by the 1% of ship mass that is fuel, and using that power to energize a larger mass of propellant and expel that larger mass at a lower speed, you can reduce the power requirements to get the desired thrust, or, get more thrust for the same power output. For example, consider a ship with 1% of the ship mass in anti-matter fuel and 49% of the ship mass in a propellant. So now, the 9*10^16 Joules of energy is distributed among 49 kilograms of propellant giving each unit of propellant gamma factor of (1+1/49). Then, thrust=gamma*v*dm/dt=(1+1/49) is now 9.95c, about a factor of 10 increase, but our ship is now twice as heavy as our unladen swallow reducing the gains somewhat. The acceleration is anywhere from 5-10 times what it was before, and the deltaV is also increased. There is some magic ratio for these things that gives you the amounts of fuel, propellant, and ship that produce the maximum acceleration, but no matter what you pick for a propellant, more energy/kg is always better.
So,provided my math is right, it seems to me that the "base" thrusters should be when the thrusters use the direct products of the power plant (fusion or anti-matter) that produces energy. These power sources may have sufficient fuel that, for the purposes of the game, they can be considered infinite(anti-matter clearly better for this), but there isn't really any feasible "infinite" power source(yeah, solar is too weak for this game...too much energy output). Consider 1% of the ship mass as anti-matter, but reduce the acceleration it produces by a factor 40...down to .25g as you suggested earlier in the thread. Then it lasts 320 hours before running out...virtually infinite unless you are too poor to replenish it when you dock. Then in addition to fuel, players could have "booster" which is really a propellant gas expelled in great quantities but at lower speeds than the typical products of these processes resulting in increased thrust and even better "fuel" efficiency if the propellant is inexpensive compared to fuel (which it should be).
Finally, with regards to the propellant, I think that it would be interesting to make the "propellant" be just about anything. After all, it doesn't matter what is from a theoretical perspective. If you can get the energy from the power plant into the liquid,gas, or solid, and shoot it out the rear of your space craft, you are golden. This allows players to "scoop" booster juice from planetary atmospheres or even, in an emergency, use cargo as booster juice. It would add an interesting tactical option. Fighters that typical function in deep space may not use boosters as much as those that function near planets. Or planetary craft which depend more on boosters might be able to have smaller power plants.