Pimp My Stardrive!

[Sundog]

Re: Pimp My Stardrive!

 

An interesting alternative: Smoots Drive (courtesy the Marvel/Epic comic series Open Space). FTL in our universe. It works like this:

 

Teleportation is possible, but only over very short distances. In fact, you can only teleport one smoot - the distance across of one hydrogen atom.

 

But the only limit on how many teleports you can make in a given time period is the amount of energy you have available.

 

Spacecraft use nuclear reactors to teleport billions of times a second. The larger the ship, the more reactors, the faster it goes. Actual distances (LY, Parsecs) matter, and you don't have to deal with alternate universes at all - unless you want to, of course.

 

Plus, Smoots drive is effectively inertialess. No need for physics bending "inertial dampeners" or artificial gravity.

 

Problems: Borders are effectively meaningless. The first you know that an enemy has declared war is when his warfleet arrives over your capital. And there's no way to stop total, uncontrolled expansion by whoever desires it.

[Spence]

Re: Pimp My Stardrive!

 

Sundog

 

I never heard of it before. Cool idea.

 

and yes, a lot of Weber as well as anything else that features "good" space combat. I lean toward space opera rather than the stories that try to turn you into an engineer. For that I prefer non-fiction. Scifi I read for fun.

[Matt Frisbee]

Re: Pimp My Stardrive!

 

Hello Spence,

 

I like the write up enough to run with it, though I would tweak a couple of points for my personal flavor.

 

1) While the idea of popping back into normal space around a star makes for a good bookend to the voyage, I like the idea that a ship could literally revert to normal space anywhere including the cold, unforgiving depths of interstellar space. That way, explorer (or enemy) ships could have the option of dropping out at a distance as they move toward the stellar primary.

 

2) I've never been a fan of instantaneous transits (sorry). I like having the transit taking some time as a function of the ship's drive power or velocity.

 

I'll finish this later -- thunderstorms moving into my area.

 

Matt "Duck-and-cover" Frisbee

[Spence]

Re: Pimp My Stardrive!

 

I normally go with a duel time thing like in post 22. All "trips" take time. But the amount time the crew/ship experiences (ShipTime) is different that the time that passes in the outside universe (RealTime).

 

Since we were knocking ideas around, I dropped the time after reading #23. I usually have the system use closed routes. It makes it easier for me as a GM. For dropping out mid point I make it due to accidents and malfunctions.

 

Also using fixed "routes" lets me use things like blockades, convoys and such.

[Matt Frisbee]

Re: Pimp My Stardrive!

 

Fixed routes are nice but too predictable for my liking -- that's probably why I never ran a system that included stargates and such.

 

Continuing my previous post, here are some other tweaks to your "rules."

 

3) I would trade out the letter hypershunts for a Class system that were rated in powers of two for maximum supra luminque distance. (Class I [2 to the power of 1 = 2 light years; Class II [2 to the power of 2 = 4 light years]; and so on.

 

4) I would tie the distance bands to some formula based on stellar mass -- thus white dwarfs and cooler stars would be highly desireable departure points. The chokepoints thing of your fixed star routes still works since ships need the mass of the star to accomplish the transition to hyperspace.

 

Other than these issues, I think your post for "rules" is extremely good! I'll probably be stealing it in the near future.

 

Matt "All-gaming-usable-material-will-be-assimilated" Frisbee

[Nyrath]

Re: Pimp My Stardrive!

 

An interesting alternative: Smoots Drive (courtesy the Marvel/Epic comic series Open Space). FTL in our universe. It works like this:

 

Teleportation is possible, but only over very short distances. In fact, you can only teleport one smoot - the distance across of one hydrogen atom.

 

But the only limit on how many teleports you can make in a given time period is the amount of energy you have available.

 

Spacecraft use nuclear reactors to teleport billions of times a second. The larger the ship, the more reactors, the faster it goes. Actual distances (LY, Parsecs) matter, and you don't have to deal with alternate universes at all - unless you want to, of course.

 

Plus, Smoots drive is effectively inertialess. No need for physics bending "inertial dampeners" or artificial gravity.

 

Problems: Borders are effectively meaningless. The first you know that an enemy has declared war is when his warfleet arrives over your capital. And there's no way to stop total, uncontrolled expansion by whoever desires it.

Just as a point of historical accuracy, that drive was invented by Poul Anderson in his "Nicholas Van Rijn" novels, back in 1958.

 

Those novels work basically the way you describe, but with a couple of important differences.

 

[1] Frequency and Phase. Ships are jumping from thousands to millions of times per second, the exact rate is the "frequency". And the "phase" controls when the ship is in real space and when the ship is jumping.

 

The important part is that if two ships have a different frequency, phase, or both, their beam weapons cannot harm each other. The jumping process chops your beam into pulses, and if you are out of frequency or out of phase, the pulses harmlessly fly through your target like bullets passing through a spinning fan blade without hitting any blades.

 

So if two mutually hostile ships want to do battle,they keep changing their frequency and phase until both ships synchronize and they exchange fire. Or if one ship is trying to avoid combat it randomly changes its settings in an attempt to avoid being hit.

 

[2] Detection. Ships in hyperdrive can be detected at a range of several light years. This avoids the "sudden enemy armada above your capital" problem. Without something like this, there are no interstellar empires, because everybody can bomb their enemies into the stone age and nobody can stop it. And their enemies can return the favor.

[Sundog]

Re: Pimp My Stardrive!

 

Just as a point of historical accuracy, that drive was invented by Poul Anderson in his "Nicholas Van Rijn" novels, back in 1958.

 

Those novels work basically the way you describe, but with a couple of important differences.

 

[1] Frequency and Phase. Ships are jumping from thousands to millions of times per second, the exact rate is the "frequency". And the "phase" controls when the ship is in real space and when the ship is jumping.

 

The important part is that if two ships have a different frequency, phase, or both, their beam weapons cannot harm each other. The jumping process chops your beam into pulses, and if you are out of frequency or out of phase, the pulses harmlessly fly through your target like bullets passing through a spinning fan blade without hitting any blades.

 

So if two mutually hostile ships want to do battle,they keep changing their frequency and phase until both ships synchronize and they exchange fire. Or if one ship is trying to avoid combat it randomly changes its settings in an attempt to avoid being hit.

 

[2] Detection. Ships in hyperdrive can be detected at a range of several light years. This avoids the "sudden enemy armada above your capital" problem. Without something like this, there are no interstellar empires, because everybody can bomb their enemies into the stone age and nobody can stop it. And their enemies can return the favor.

 

Cool. I've read some of the van Rijn pieces, but I've never encountered a description of how their stardrive worked (nor in the Flandry stories that are set later in the same universe).

 

The detection system prevents suden decapitation strikes, but borders would still be swiss cheese unless you were willing to patrol very heavily. In the Open Space version you could neither engage nor track a vessel in Smoots Drive - aside from anything else, he could just turn away and be out of detection range before you could react.

[Nyrath]

Re: Pimp My Stardrive!

 

Cool. I've read some of the van Rijn pieces' date=' but I've never encountered a description of how their stardrive worked (nor in the [b']Flandry[/b] stories that are set later in the same universe).

There was a description in one of the van Rijn stories, the one where van Rijn figures out how to send merchant starships through Space Pirate Dry Gulch star pass, despite the fact that arming the merchants would eat up all the profit margin. I cannot remember the story name.

 

In TRADER TO THE STARS:

It disappeared. Recoil sent the yacht staggering.

 

"Beelzebub and botulism!" snarled Van Rijn. "He went back Into hyper, ha? We see about that!" The ulcerated converter shrieked as he called upon it, but the engines were given power. On a lung and a half, the Terrestrial ship again overtook the foreigner. Van Rijn phased in so casually that Torrance almost forgot this was a job considered difficult by master pilots.

 

In ENSIGN FLANDRY:

...She had fired a missile salvo: the monster missiles which nothing smaller than a battleship could carry, which had their own hyperdrives and phase-in computers...

 

...Faster than either battleship, Umbriel had overhauled her giant foe. When drive fields touched, she went out of phase, just sufficient to be unhittable, not enough that her added mass did not serve as a drag. The Merseian must be trying to get in phase and wipe her out...

[Chris Goodwin]

Re: Pimp My Stardrive!

 

How does a closed timelike curve sound?

[Cancer]

Re: Pimp My Stardrive!

 

Some time ago I briefly described some of my ideas in this thread. Sounds like you've already decided on other ideas, though.

 

EDIT: here's another thread that I remember bearing on these questions.

[Nyrath]

Re: Pimp My Stardrive!

 

How does a closed timelike curve sound?

Like a time machine. Because "closed timelike curves" is scientist jargon for a time machine.

 

Which is one of the reasons why conventional physicists dismiss the possibility of stardrives.

 

I think we should ignore closed timelike curves because:

[1] We want stardrives to exist for our campaigns.

[2] We generally do not want time machines in our campaigns (unless we are actuall running a time travel campaign).

[Nyrath]

Re: Pimp My Stardrive!

 

There was a description in one of the van Rijn stories' date=' the one where van Rijn figures out how to send merchant starships through Space Pirate Dry Gulch star pass, despite the fact that arming the merchants would eat up all the profit margin. I cannot remember the story name.[/quote']

Aha, found it.

 

"Margin of Profit" by Poul Anderson. One of his better short stories.

 

* Astounding Science Fiction, September 1956

* Un-Man and Other Novellas / The Makeshift Rocket Poul Anderson

* The Earth Book of Stormgate Poul Anderson

* The 7 Deadly Sins of Science Fiction Isaac Asimov, Martin H. Greenberg, Charles G. Waugh

 

http://www.bookfinder.com is your friend.

[Chris Goodwin]

Re: Pimp My Stardrive!

 

Like a time machine. Because "closed timelike curves" is scientist jargon for a time machine.

 

Hehe.

 

I don't recall if it was Stephen Baxter or someone else who came up with a "closed spacelike curve" as a direct play on the timelike version.

 

I'm not a physicist at all (I deleted several amusing typoes on the word "physicist" which would have been great fun had I left them) but it seemed to me that part of the description of "closed timelike curve" included the possibility of a "very fast drive" of some kind. Probably still sublight but pretty darn fast, at least.

[Matt Frisbee]

Re: Pimp My Stardrive!

 

Okay, here's a rough draft of the basics. Sorry if it reads like stereo instructions.

 

The Pimped Stardrive System (courtesy of thread contributors, but especially Spence):

System Classification: Stardiver

Basic Theory

The gravitation and magnetism of a star combine to produce areas of stressed normal space around it. This stressed area of space is called the Interphase Zone. Under ideal conditions, high velocity objects can cross the dimensional barrier and be thrown temporarily into hyperspace when within the volume of an Interphase Zone. Such objects are usually destroyed upon contact with the hyperspace medium, since hyperspace is a parallel universe that is only 1/10,000th the size of normal space. However, spacecraft fitted with a hyperspace shunt can access hyperspace by emitting an intense pulse of magnetic energy at the precise moment the ship reaches an Interphase Zone, transitioning it to hyperspace.

As a ship transitions, the pulse of magnetic energy it created converts into a compression wave that enfolds the ship with a small bubble of normal space, much like a super-cavitating marine projectile is enclosed in a small bubble of air or vacuum. This compression bubble protects the ship from the hyperspace medium which would otherwise destroy the ship due to friction. Due to this friction, the compression bubble does have a finite lifespan, eventually decaying to a point where the ship reverts back to normal space.

Stars of 0.8 solar masses or more can create Interphase Zones, though more massive stars combined with more powerful hyperspace shunts are capable of transitioning ships for longer periods of time (and thus greater normal space distances). The ship in hyperspace cannot affect its ballistic trajectory (most ships cut their engines just before transition), and must coast during the journey until transitioning back to normal space. Because of this, the entry vector relative to the stellar mass and intended destination (as adjusted by the additional dimensions of hyperspace) as well as the energy discharged into the shunt determine where the ship emerges into normal space. Even small deviations of any variable in the transition can translate into very large changes, especially with longer transits.

As a rough guide to potential transit distance in parsecs, multiply the stellar mass of the star, by the class of the hyperspace shunt carried by the ship, and the maximum speed the ship can reasonably attain on the approach in tenths of AU per hour. Thus, a ship approaching a star of 1.4 stellar masses with a class 2 hyperspace shunt at a speed of 0.13 AU per hour, could achieve a maximum transit of (1.4 x 2 x 1.3 =) 3.64 pc or about 11.9 light years. Most civilian ships would limit their transits to approximately one half of their potential maximum, since such transits enable their navigators more confidence in their transit plotting calculations.

While they may be found in many locations around a star, the most typically used transit points are found along the axis of a star's rotation. The best point to use is the one closest to the star, which is found a number of AU from the star's center equal to one-quarter of its mass in solar masses. Thus, the star used in the example's best point would be (1.4 x 0.25 =) 0.35 AU from its center. Other points can be found at half the best point distance around the star, but due to the dangers of intense light, heat and radiation, most ships avoid these points except in absolute desperation (GM fiat).

More to come -- but input appreciated!

 

Matt "The-deranged-GM" Frisbee

[Spence]

Re: Pimp My Stardrive!

 

Great write-up.

[Sundog]

Re: Pimp My Stardrive!

 

Aha, found it.

 

"Margin of Profit" by Poul Anderson. One of his better short stories.

 

* Astounding Science Fiction, September 1956

* Un-Man and Other Novellas / The Makeshift Rocket Poul Anderson

* The Earth Book of Stormgate Poul Anderson

* The 7 Deadly Sins of Science Fiction Isaac Asimov, Martin H. Greenberg, Charles G. Waugh

 

http://www.bookfinder.com is your friend.

 

Excellent. I'll track a copy down as soon as I have time.