Steve Jackson Games - Site Navigation
Home General Info Follow Us Search Illuminator Store Forums What's New Other Games Ogre GURPS Munchkin Our Games: Home

Go Back   Steve Jackson Games Forums > Roleplaying > GURPS

Reply
 
Thread Tools Display Modes
Old 05-21-2019, 06:09 AM   #21
Anaraxes
 
Join Date: Sep 2007
Default Re: Skill level of an automated sentry gun?

Quote:
Originally Posted by Rupert View Post
the problem of having to choose between 'prone to false positives' (wasting ammo, possibly killing civilians, possibly running the system dry just before a real attack), and 'prone to false negatives' (your ship gets sunk).
The Phalanx CIWS has stations for human operators to visually identify and even manually target threats. They added that capability along with the infrared system that allows the system to target helicopters and small surface boats, possibly to help with exactly this IFF problem. (Or at least shift the blame back to the humans...)

A fictional sentry gun might well have any number of modes of operation from manual human remote control to requires-approval-per-target to auto-skip-questionable-IDs to kill-everything-that-moves.
Anaraxes is offline   Reply With Quote
Old 05-21-2019, 06:20 AM   #22
Rupert
 
Rupert's Avatar
 
Join Date: Aug 2004
Location: Wellington, NZ
Default Re: Skill level of an automated sentry gun?

Quote:
Originally Posted by Anaraxes View Post
The Phalanx CIWS has stations for human operators to visually identify and even manually target threats. They added that capability along with the infrared system that allows the system to target helicopters and small surface boats, possibly to help with exactly this IFF problem. (Or at least shift the blame back to the humans...)
Finding small surface boats amongst the surface clutter with a radar is not very reliable. Adding helicopters to the radar system would be easy, adding in IFF probably not that hard, but it's another layer of complication, and not something you really need to completely automate on a ship.
__________________
Rupert Boleyn

"A pessimist is an optimist with a sense of history."
Rupert is offline   Reply With Quote
Old 05-21-2019, 06:23 AM   #23
Anaraxes
 
Join Date: Sep 2007
Default Re: Skill level of an automated sentry gun?

Quote:
Originally Posted by Rupert View Post
Finding small surface boats amongst the surface clutter with a radar is not very reliable.
The Block 1B CIWS adds (along with that human interface) an infrared sensor for those targets. Still not perfect, but I suspect the human is there because it's so much more likely that you'll have friendly or civilian boats and helicopters around than you will objects travelling at anti-ship missile velocities on intercept courses with the ship. Plus those categories of target are slower, so there's more luxury of time to decide whether or not to let the thing blow up that speedboat.
Anaraxes is offline   Reply With Quote
Old 05-21-2019, 07:12 AM   #24
kdtipa
 
kdtipa's Avatar
 
Join Date: Jun 2007
Location: Southern New Hampshire
Default Re: Skill level of an automated sentry gun?

Quote:
Originally Posted by Fred Brackin View Post
I get the idea that you're supposed to design all robots as characters.
I agree. This seems like the way to go to design a "sentry gun" that can recognize targets and fire on its own. This way you get a strength score that can tell you how strong the motors are and give you a basis for hit points and weight. You get a DX score that you can base the physical skills on. You get an IQ score and Perception score that provide a basis for understanding commands; recognizing targets; picking correct targets; and so on. You get a HT score to roll against to see when it stops functioning. You can pick advantages and disadvantages that make it into a robot, and potentially give it different kinds of sensors. The only thing missing I think is a translation to how expensive it would be, but you could pick what you think is a fair price for your setting easily enough.
kdtipa is offline   Reply With Quote
Old 05-21-2019, 07:55 AM   #25
JackFalcon13
 
Join Date: May 2019
Default Re: Skill level of an automated sentry gun?

Quote:
Originally Posted by Rupert View Post
No, the high rate of fire is needed to allow for inaccuracies in the firing solution and the translation of that to bullets in the air. The radar's resolution isn't perfect, there's some slop and error in the turret's training mechanisms, and the stabilisation isn't perfect. It all adds up, and even a 'big' Russian missile isn't a huge target (and the big Russian missiles are very fast, so you can't afford to miss the first time).
Oh, I agree with you. Without debating the accuracy of systems that have a classified functionality, my point is a giant array of much bigger guns with a much bigger engagement radius is probably better. But most ships can't handle 20+ gun batteries to engage a missile. The lower weight replacement for that is just use missiles. God knows we spend enough on defense for that. The RAM pretty much kills anything, you just have to be able to expend more missiles than they have. Now, once we get effective laser weapons, that might change things. But I think we're about a decade from that. And we were a decade from them a decade ago.
JackFalcon13 is offline   Reply With Quote
Old 05-21-2019, 08:08 AM   #26
Anaraxes
 
Join Date: Sep 2007
Default Re: Skill level of an automated sentry gun?

Quote:
Originally Posted by JackFalcon13 View Post
Now, once we get effective laser weapons, that might change things. But I think we're about a decade from that. And we were a decade from them a decade ago.
On the bright side, you'll be able to power your laser weapons with fusion, since that's pretty much the same timescale away...
Anaraxes is offline   Reply With Quote
Old 05-21-2019, 10:04 AM   #27
The Colonel
 
The Colonel's Avatar
 
Join Date: Jul 2006
Default Re: Skill level of an automated sentry gun?

I think they were trying to sell the MetalStorm concept weapons as point defence at one point, based on the fact that their theoretical cyclic rate is immense … effectively giving them the capacity to put a wall of projectiles in the way of the missile.
The Colonel is offline   Reply With Quote
Old 05-21-2019, 01:11 PM   #28
Verjigorm
 
Join Date: Jan 2005
Location: Charlotte, North Caroline, United States of America, Earth?
Default Re: Skill level of an automated sentry gun?

Quote:
Originally Posted by The Colonel View Post
I think they were trying to sell the MetalStorm concept weapons as point defence at one point, based on the fact that their theoretical cyclic rate is immense … effectively giving them the capacity to put a wall of projectiles in the way of the missile.
To be fair, I started with the 64mm mortar box from UT as the basis for an anti-missile system.
__________________
Hydration is key
Verjigorm is offline   Reply With Quote
Old 05-21-2019, 09:59 PM   #29
AlexanderHowl
 
Join Date: Feb 2016
Default Re: Skill level of an automated sentry gun?

The difficulty of shooting down fast missiles is one of the reasons why research continues into coilguns, lasers, and railguns. Hypothetically, a coilgun could fire thousands of rounds per second, at 1 km/s, giving even a 10 gram object 5 kJ of energy. Of course, there is nothing reliable yet.
AlexanderHowl is offline   Reply With Quote
Old 05-22-2019, 03:45 AM   #30
Žorkell
Icelandic - Approach With Caution
 
Žorkell's Avatar
 
Join Date: Jan 2005
Location: Reykjavķk, Iceland
Default Re: Skill level of an automated sentry gun?

Quote:
Originally Posted by AlexanderHowl View Post
The difficulty of shooting down fast missiles is one of the reasons why research continues into coilguns, lasers, and railguns. Hypothetically, a coilgun could fire thousands of rounds per second, at 1 km/s, giving even a 10 gram object 5 kJ of energy. Of course, there is nothing reliable yet.
So it can fire lots of bullets at about the velocity of a rifle bullet? 1 km/s is 3280 feet per second. Taking a very cursory look at it the velocity of modern rifle bullets (7.62 NATO and 5.56 NATO) seems to be in the 900 to 1000 m/s range.
__________________
Žorkell Sigvaldason

Viking kittens | My photos | More of my photos
Žorkell is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Fnords are Off
[IMG] code is Off
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 04:59 AM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2024, vBulletin Solutions, Inc.