Gravity, Inertia, and Star Hero

[doublefine]

Well, I'm relatively new around here...I ordered the Star Hero Bundle the other day, and I'm rather breathlessly awaiting it's arrival. In the mean time I started to get bored, so I started thinking about some acceleration conversions I did for the Traveller Hero Board.

 

Then I started looking at physics websites. Which was probably at least my second mistake.

 

Regardless, I started pondering the effects, if any, that could be applied in Star Hero, mainly those that would act on starships. Useing my newly won...(snort)...knowledge of physics I started looking at gravitational effects. Those of you that have actually played in Star Hero campaigns, is this generally worthwhile? I figure inertia at least should be a viable game mechanic, but it doesn't really present in a normal Hero game, the only type I've really played. After all, there's nothing quite like seeing players come to the conclusion that they can either get into position to do something (and fly into the Sun), or wait and possibly come too late to be of use.

 

I had thought that a rough simulation of Gravity effects might work well, but then again they might also be fairly negligible and only wind up costing me extra work.

 

I think I've found most of the relavent equations neccesary, but I really would like opinions before I possibly waste several days/weeks/months quantifying something that everyone is going to hate.

 

Thanks in advance.

[TheRavenIs]

Re: Gravity, Inertia, and Star Hero

 

Hey doublefire. As to you question....it all depends. How 'real' are you going to make your game world. The more real then the more you need to address real world physics. The more you go into rubber science the less you need to worry about it.

[EvilDrPuma]

Re: Gravity, Inertia, and Star Hero

 

You may be relieved to know that Star Hero does contain rules options for realistic acceleration, inertia, gravity and the like. The book doesn't assume you will be paying attention to such things, but the mechanics are there if you want them. You may not need to do as much work as you think, if "hard" science fiction is your goal.

[doublefine]

Re: Gravity, Inertia, and Star Hero

 

That is mildly comforting EDP. Although I must say that the masochistic part of me was actually looking forward to hashing it all out myself. Then again, the Hero System and I do not always agree (which, honestly is why I use the Hero System...you can change just about anything a lot more easily than any other system I've used). So I may go ahead and do it anyway once I get the books, but what I'm looking for is basically opinions on how the more "realistic" mechanics usually impact gameplay...I'd like to have some realism, but I also don't want to bog my players down with a lot of rules, that in the end are only going to be an inconvience to everyone. After all, this is supposed to be fun...few people are going to have fun spending an hour calculating the most fuel efficient course for their pretend spaceship.

 

Edited to avoid angering giant space feline

[austenandrews]

Re: Gravity, Inertia, and Star Hero

 

It entirely depends on the group. Some people dig the science and enjoy spending gaming time to work out the details. Others would rather handwave the flight mechanics and get on with the story. I've seen way more of the latter than the former, but I have seen the former.

 

(Is it Cancer's group that contains several astrophysicists?)

[Cancer]

Re: Gravity, Inertia, and Star Hero

 

You called?

 

In any sci-fi game-world the choice of how interstellar travel works is an important decision on how the campaign is going to run. That can involve careful attention to real physics, or not.

 

I can say from experience: you can sink a lot of time into the physics, have a great time grinding all the math stuff out, and end up with a campaign that no one else wants to play in. Great fun for you, could be a spiffy setting for a story, but other folks have their own ideas about what's fun for them, and an attempt to play in that game-world could end up being a three-session train wreck.

 

I go back and forth about this sort of thing. Obviously I enjoy pushing the math around, but there are popular "sci fi" settings out there where physics and economics are absolutely disregarded (Serenity/Firefly is one of the new popular ones), as all they would do is get in the way of the story. How much that bothers you and your players is a matter of personal choice.

 

I would love to do "top-down" universe creation, decide on physical principles, build ecosystems, societies, and commercial networks based on those "first principles" ... it's just that most choices for such things are dead ends in terms being viable self-consistent worlds. (I remember my reaction the first time I pushed numbers around and found that a modest spaceship whose thrust was produced by a laser needs of order 10^15 watts continuous out of that laser to make 1 gee of acceleration... Now, what power source was I planning on using again?)

[austenandrews]

Re: Gravity, Inertia, and Star Hero

 

(I remember my reaction the first time I pushed numbers around and found that a modest spaceship whose thrust was produced by a laser needs of order 10^15 watts continuous out of that laser to make 1 gee of acceleration... Now' date=' what power source was I planning on using again?)[/quote']

Microscopic wormholes into stellar cores?

[keithcurtis]

Re: Gravity, Inertia, and Star Hero

 

Microscopic wormholes into stellar cores?

If you can do that, why bother with a laser? Use the superheated and pressurized mass of the star as propellent. You won't even have to carry any reaction mass.

I came to the same conclusions researching the Solar Colonies. I eventually settled on a Nivenesque "Fusion Drive". The problem is that to make them work with anything approaching the efficiency of Known Space Fusion Drives, you need a thrust akin to a whopping gigantic particle cannon. It's no wonder the humans were able to defeat the Kzinti.

It raised a lot of questions beyond the math of the situation, too. With thrusts that powerful, every ship is a navigational hazard and a severe danger to any nearby settlement (nearby in astronomical terms, that is). How do you protect yourself from an inept or psychopathic or terrorist ship pilot?

 

Keith "Mucho handwaving" Curtis

[austenandrews]

Re: Gravity, Inertia, and Star Hero

 

If you can do that' date=' why bother with a laser? Use the superheated and pressurized mass of the star as propellent. You won't even have to carry any reaction mass.[/quote']

Good question. What reason would justify using a laser as opposed to shooting stellar matter through a nozzle? Maybe wormholes only work in spurts, whereas stored energy directed through a laser can be used at any time. Just thinking out loud. (My ultimate point is, it's fun to figure out why something that sounds unreasonable isn't.)

[Cancer]

Re: Gravity, Inertia, and Star Hero

 

Newtonian-mechanics based space flight on human-interesting timescales takes stupendous amounts of power, and there's no way around that. And as Keith points out, if you have that power, it ought to be Really Easy to things which are usually incovenient for campaign plot, like sterilize planets from far away.

[austenandrews]

Re: Gravity, Inertia, and Star Hero

 

Newtonian-mechanics based space flight on human-interesting timescales takes stupendous amounts of power' date=' and there's no way around that. And as Keith points out, if you have that power, it ought to be Really Easy to things which are usually incovenient for campaign plot, like sterilize planets from far away.[/quote']

Isn't that pretty much the case with any setting that involves spaceships zipping around at high speed?

[Cancer]

Re: Gravity, Inertia, and Star Hero

 

Isn't that pretty much the case with any setting that involves spaceships zipping around at high speed?

 

Not necessarily. Getting to high speed doesn't have to take a lot of power; you can do it with low power and lots of time (and "lots" here means at least months, more likely years ... many years). That's a pretty boring universe for an RPG, though.

 

Low power also means that planet-bombing is harder. Early detection of incoming objects is possible, with time enough to do something about it.

[austenandrews]

Re: Gravity, Inertia, and Star Hero

 

Not necessarily. Getting to high speed doesn't have to take a lot of power; you can do it with low power and lots of time (and "lots" here means at least months, more likely years ... many years). That's a pretty boring universe for an RPG, though.

 

Low power also means that planet-bombing is harder. Early detection of incoming objects is possible, with time enough to do something about it.

Well, I meant settings that people would actually tell stories in.

 

One ship the mass of a large building could wipe out a city at relatively low speed. At high speed it could trash a whole ecosystem. I always figured it was just one of those general SF assumptions that people don't do that to each other, because there's hardly any way to stop it.

[Zeropoint]

Re: Gravity, Inertia, and Star Hero

 

I deliberately went for a "space opera" feel in my Star Hero game, so as not to drive myself mad trying to work out all the details. My main concession to Newton regarding space travel is to give all spacecraft an infinite non-combat multiplier for free. This allows the wimpiest, most overloaded cargo ship to get up to a decent speed, and not spend days trying to get far enough from a planet to go to hyperspace, while still allowing "fast" ships (that have more inches of flight) a real advantage, in terms of both accelleration and combat maneuverability.

 

It's also strongly suggested that a ship have an artificial gravity system capable of matching it's acceleration.

[LunaRagno]

Re: Gravity, Inertia, and Star Hero

 

The patches Star Hero puts on the Hero sys movement rules aren't near good enough. Prob is, Hero assumes all movement needs force applied to maintain speed; stop pushing, you slow down real quick (or stop immediately). Also, don't matter how long you add force, you can only go jest-so-fast.

 

For realistic space flight, that's BS. The additional rules Star Hero has are first off just a patch and second off are bloody poorly thought out and written.

 

You say you've done Traveller. Do you have the original half-sized books? If you do, go to Book 2: Starships and use the combat system there. It's dam close to The RealWorld™, and pretty simple. Of course, it takes up your whole floor...

 

[Nyrath]

Re: Gravity, Inertia, and Star Hero

 

I'm the author of the atomic rocket website, and generally like the science in my SF to be quite hard.

 

However, having said that, for the purposes of playing Star Hero, I believe that the focus of a game master's efforts should be on what the players want. That is, if the players wouldn't recognize Newton's laws if they flew straight up their collective behinds, it is a waste of a game master's always limited time to work out the mathematics of space travel. The time would be better spent inventing intricate plot seeds and diabolical plot twists, which will give the players more enjoyment.

 

I second LunaRagno's suggestion to use the original Traveller vector movement rules. It might be even easier for your players to use something like the Triplanetary game rules, unfortunately the game is out of print. Fortunately the rules are available as a pdf file at the first link.

[doublefine]

Re: Gravity, Inertia, and Star Hero

 

Unfortunately, while I'm offering my opinions on on certain Hero adaptations of Traveller ships...I've never played Traveller, and I don't have any of the books.

 

Honestly at this point I'm thinking of going with inertia (ie. movement not taken within a planetary atmosphere doesn't stop until cancelled by another equivalent move, either provided by the ship itself or by the following gravity draft) and gravity (using basic Newton a=m/d squared or acceleration equals mass, I'm probably only going to map out the major planetary bodies, divided by the distance to our ship squared).

 

I'm thinking of shading rough estimates of the acceleration around the requisite planets, and using those for simplicities sake.

 

Questions, opinions, comments welcome.

[bigdamnhero]

Re: Gravity, Inertia, and Star Hero

 

I'd like to have some realism' date=' but I also don't want to bog my players down with a lot of rules, that in the end are only going to be an inconvience to everyone. After all, this is supposed to be fun...few people are going to have fun spending an hour calculating the most fuel efficient course for their pretend spaceship.[/quote']

Absolutely. I'm with you in that I much prefer vector-based movement; realism aside, I just think it gives space battles a unique feel, very different from naval or air battles. The trick IMO is to come up with a simplified system that is based on realistic physics, but is pared down enough to be playable.

 

The "realistic" movement rules in SH actually aren't bad, although I wish they'd fleshed them out a bit more. If I ever get around to running my SH campaign, I was planning to meld the vector movement system from Full Thrust onto SH. Full Thrust is also currently out of print -- an updated version is supposedly coming out any year now -- but is available as a pdf from Ground Zero Games. (Under downloads. The main FT rules use "cinematic" movement, but the Fleet Books have an optional vector movement system that is just the right amount of simple IMO.)

 

Unfortunately' date=' while I'm offering my opinions on on certain Hero adaptations of Traveller ships...I've never played Traveller, and I don't have any of the books.[/quote']

You're in luck: in case you haven't heard, Traveller Hero is on its way!

 

Oh, and welcome to the boards!

[LunaRagno]

Re: Gravity, Inertia, and Star Hero

 

I'm sorry my post was so snippy. I went too far in attacking Space Hero's movement system.

 

doublefine: in your last post you're pretty near described the Book 2 system.

 

Nyrath, bigdamnhero: I'll have to check those out.

[doublefine]

Re: Gravity, Inertia, and Star Hero

 

I'm sorry my post was so snippy. I went too far in attacking Space Hero's movement system.

 

doublefine: in your last post you're pretty near described the Book 2 system.

 

Well, I wouldn't worry about the first bit...especially with the Hero Sysytem...they're very good about flexibility. If you don't like it you don't like it, and honestly that's one of the things that I don't particularly like about the Hero system myself. It's very unrealistic, but you can kind of see where they were coming from with it, as it does simplify the bookkeeping involved. If you had to deal with Inertia, or Gods forbid potential energy, then the GM and players would have to spend entirely to much time to do anything. But with Starship physics you'd think they'd make a general exception to the rules...oh well, that's why they embeded so much flexibility into the system, and also why most of what they write are suggestions rather than hard rules.

 

And...off the soapbox for the moment.

 

It's good to know that I can come up with something that's pretty close to things I've never even seen before...although that might speak more to the "common sense" approach of the Traveller folks than anything else.

 

and Bigdamnhero...I know they're coming out with TravHero...I'm posting suggestions for Shadowcat on the TAS board...

 

Although I did come across http://www.starherofandom.com/b5/index.php the other day...which is a bit closer to my heart, as I've been around B5 a bit longer...Although as far as I can tell the author is trying to charge his players for using the increased movement in hyperspace, but I'm probably reading that wrong...