Antigravity & Inertial Dampening

[Tom Kalbfus]

The grav drive field effect has to react to some form of significant gravity focus.

Not in Mgt

What happens if a Scout/Courier pulls up to a one billion ton asteroid, such that it is inverted a few meters from the surface of the asteroid, and then turns on its grav plating so that the crew feels 1-g of gravity on the inside of the ship? Does the one billion ton asteroid which is just above the scout/Courier fall onto of it with one billion tons of force under that artificial gravity? Does the artificial gravity stop at the surface of the ship or does it continue other to the asteroid, pulling that asteroid onto itself?

 

[Infojunky]

What happens if a Scout/Courier pulls up to a one billion ton asteroid, such that it is inverted a few meters from the surface of the asteroid, and then turns on its grav plating so that the crew feels 1-g of gravity on the inside of the ship? Does the one billion ton asteroid which is just above the scout/Courier fall onto of it with one billion tons of force under that artificial gravity? Does the artificial gravity stop at the surface of the ship or does it continue other to the asteroid, pulling that asteroid onto itself?

1st answer; Whatever amuses the GM the most! (aka the Toon! answer)

2nd, general supposition is that the the Anti Gravity effect is localised to the inside of the ship. This from other editions examples, rules and art.

 

[Reynard]

Have you any idea how much effect that billion ton asteroid would suffer if a 100 ton ship's gravity field neared it?

None at all.

 

[phavoc]

I believe that the fields are generated via deck plating, and would, I'm assuming here, extend towards the standard 1Dton section. We already know that control of it can be localized, and that the fields don't extend beyond the external hull (though this is more an assumption than anything else).

The other suppositions are localized gravity via the deck plates creates and independent field that overrides the acceleration of the drive. So that makes it not a inertial dampening field per se, but in effect it acts like one.

What we don't quite have down pat is to what level it can work. Small craft under 70 tones are capable of making much higher G than a starship and there are no special rules to protect the pilot from the high-G forces. So we must assume that somehow the pilot is under the effect of a very small grav plate built into the cockpit (or else he'd be dead when the ship was continually boosting for 12Gs). Larger M-drives cap out at 6G capabilities. So there is a gap in the explanation between the two.

 

[Condottiere]

I'm inclined to think that the ship's computer handles it the same as it controls the compensators, it detects the gravitic pressure and lowers onboard gravity.

What would be interesting is if it can adjust the shipboard gravity to counter the effect of above norm standard gravity.

 

[Reynard]

Core Book page 144 under Security Systems says the internal gravity can be reduced to zero or up to 3G. Add to that the AC/IC system adjusts to inertial changes which is a form of gravitational effect and it seems very possible it adjusts for both gravity free and high gravity environments.

 

[simonh]

All just IMHO:

I imagine internal gravity is a field generated between plates in the floor and ceiling of each deck, so it doesn't extend outside the ship.

Inertial compensation is performed by the same kind of plates fitted into the outer walls of each deck. The most powerful compensation plates would be aligned along the primary axis of the ship, so if the drive fires up at a rating of 3G, the compensation field generates a 3G field 'pulling' the crew towards the front of the ship, neutralising the effect of the drive. These plates are linked to the ship's drive controls, so they compensate for changes in thrust.

This would be imperfect though because the positioning and geometry of the plates, and variations in the field strength across each deck, etc would not be perfectly uniform. This means there would be brief uneveneess in the damping effect during rapid manoeuvers, until ship's computer fine tunes the field geometry. Also, it can't compensate very well for unanticipated accelerations such as impacts/explosions.

The floor, ceiling and wall plates coudl also be used to counter the effect of external gravity fields, so if you land on a low or high gravity planet, you can still maintain a comfortable 1G environment in the ship.

I liked the way lateral thrust worked in Mega Traveller. It suggested that drive thrusters can generate their full thrust rating directly in line witht he drive axis, but can generate off-axis thrust at progressively smaller percentages of their main rating, with the lowest thrust beign 10% of full rating in the opposite direction and 25% at 90 degrees. I can't remember if they said this, but I assume ships can generate higher lateral thrust, up to their full rating or even more, for brief periods of time, enough for short atmospheric operations and take-off/landing. Alternatively you could assume that the drives operate more efficiently in a planetary gravity field, hand-waving away the issue of how a ship with a 1G drive can safely land or take off from a planet with 1G+ gravity.

Simon Hibbs

 

[phavoc]

Having a computer keep coordinate between the deck plating fields and the drive field seems to me like a disaster waiting to happen. From a pure safety factor you really want the deck plates to always be projecting out their field regardless of what the drive is doing. Internal gravity needs to be one of those systems that simply cannot fail, or if it does it needs to fail with warning. I would assume there would be some sort of battery power in the deck plating to ensure that immediate power loss takes at least a few seconds to counter the fields, to give people time to prepare, or perhaps in the event of failure the field spools down in say 60 seconds to minimize the impact of smacking into the decking.

 

[Reynard]

The majority of ships in flight do not involve anything but constant acceleration as the crow flies. Not every military craft is constantly involved in battles needing radical vector changes or battle damage. Because of that, AG/IC will have standard safety features at reasonable cost, otherwise known as Core Rule Book Value. When power systems fail, including compensators, there will be velocity in the last direction so everything inside will move together at that velocity. No one gets throw about when the power goes off though they will be affected by zero g. They will float in whatever direction they happen to push away from and no one floats 'up', that's holovid cinema. Having Zero-g skill trains you to such events. When power and gravity are about to be restored, I'm quite sure there will be a ship wide announcement for preparation. The funny guy 'standing' on the ceiling will learn a painful lesson for next time.

I would say ship safety could include acceleration features in chairs at work stations especially in military vessels that do experience vector changes and emergency power surges or outages due to battle damage. At least the bridge duty chairs on civilian ships should have them. Subsidized liners normally won't be doing one-eighties or evading pirate weapon fire.

 

[Reynard]

All this concerning the AG/IC system should also be a reminder that the ship's computer system is big for a reason. One of the subsystems is taking care of all the massive inertial sensor readings and command outputs to the IC's plates throughout the ship at nano speeds with backups.

 

[F33D]

All this concerning the AG/IC system should also be a reminder that the ship's computer system is big for a reason.

In MGt the computer is so small that you don't have to allocate tonnage. Maybe you meant "powerful"?

 

[F33D]

Core Book page 144 under Security Systems says the internal gravity can be reduced to zero or up to 3G. Add to that the AC/IC system adjusts to inertial changes which is a form of gravitational effect and it seems very possible it adjusts for both gravity free and high gravity environments.

That would be a logical assumption given those rules.

 

[GypsyComet]

The grav drive field effect has to react to some form of significant gravity focus.

Only at low tech. Standard M-Drives require no "significant" gravity to work in.

Different editions have gone back and forth over this set of capabilities being one drive or several.

As long as the math of ship design works the same, use the practical model that works for you.

 

[phavoc]

The majority of ships in flight do not involve anything but constant acceleration as the crow flies. Not every military craft is constantly involved in battles needing radical vector changes or battle damage. Because of that, AG/IC will have standard safety features at reasonable cost, otherwise known as Core Rule Book Value. When power systems fail, including compensators, there will be velocity in the last direction so everything inside will move together at that velocity. No one gets throw about when the power goes off though they will be affected by zero g. They will float in whatever direction they happen to push away from and no one floats 'up', that's holovid cinema. Having Zero-g skill trains you to such events. When power and gravity are about to be restored, I'm quite sure there will be a ship wide announcement for preparation. The funny guy 'standing' on the ceiling will learn a painful lesson for next time.

I agree with you in that most travel is going to be relatively boring and pretty straight line. However given that most PC's craft are equipped with weapons, and many ships are armed (not including military), there's going to be the sort of maneuvering that has been suggested. A ship without deck plate fields is going to exert the effects of the maneuver drive and the maneuvering on the crew and contents of the ship. And since most ship designs have decking along the same plane as the thrust, everyone and everything not tied will slide towards the rear bulkheads along the direction of the drive. And radical maneuvers will also throw the contents and crew about.

I would say ship safety could include acceleration features in chairs at work stations especially in military vessels that do experience vector changes and emergency power surges or outages due to battle damage. At least the bridge duty chairs on civilian ships should have them. Subsidized liners normally won't be doing one-eighties or evading pirate weapon fire.

I agree that crew stations will have built-in capabilities to support the crew performing their duties in potential zero-g. With military crews having more robust systems since, in theory at least, they'll be far more likely to engage in combat with potential catastrophic results, than a civilian ship.

 

[Condottiere]

It's an all size fits all; there are probably different grades for military and civilian usage.

 

[Tom Kalbfus]

What about booby trapping the gravity plating? This was done on a episode of the Star Trek show Enterprise. An intruder steps on a certain section of deck and the artificial gravity is maximized to pin the intruder to the floor.

 

[Condottiere]

Better if you keep falling and hitting the floor and ceiling.

 

[phavoc]

What about booby trapping the gravity plating? This was done on a episode of the Star Trek show Enterprise. An intruder steps on a certain section of deck and the artificial gravity is maximized to pin the intruder to the floor.

That's listed in the CRB as a potential way of engaging hijackers onboard.

 

[Reynard]

"However given that most PC's craft are equipped with..."

PCs are not normal at any level!

 

[Condottiere]

Given the pricing on smallcraft hulls, they, too, have a full set of artificial gravity and inertial compensators.