Sensor Buoys and Mines

[Steve Walmsley (OP)]

This is a whole new area for v3.2 and it's based on some suggestions made by Matt Wadwell several versions ago. Until last night I hadn't figured out a good way to handle this but the lightbulb has finally gone on

When you go to the Missile Design window you can now choose to design either missiles or buoys. They are both treated as missiles in the game and function under exactly the same rules, the difference is purely in design. Missiles have all of the options that they previously had. Buoys can't have warheads, engines, fuel or agility and instead gain reactors.  A reactor can power a buoy for a number of months equal to the reactor power of your latest reactor tech multiplied by the Missile Size Points (MSP) of the reactor. For example a Pebble Bed Reactor has three points of power per HS, so it also has three months of endurance per MSP. If you have 2 MSP on the buoy, it will have an endurance of six months. You can add sensors to a buoy design, just like a missile, so you can create bouys with active, thermal or EM sensors, or a combination of the above. Once off the missile design window, buoys become just like any other missile. You can build them in ordnance factories, you can add them to ship's magazine and you fire them from missile launchers, although they just remain where you fire them. Here is a simple example of a small thermal sensor buoy. It has 1 MSP of thermal sensors and 2 MSP of reactor. It would be ideal for leaving at a planet or close to a jump point for monitoring traffic.

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Thermal Sensor Buoy
Buoy Size: 3 MSP  (0.15 HS)     Armour: 0
Reactor Endurance: 6 months
Thermal Sensor Strength: 0.25    Detect Sig Strength 1000:  250,000 km
Cost Per Buoy: 1.45
Materials Required:    0.25x Uridium, 1.2x Boronide
Development Cost for Project: 145RPHere is where it starts to get interesting. You can create missiles with buoys in the second stage or vice versa. So lets create a new Heat-seeking missile using the normal missile design rules (actually this is using the new more granular missile design rules so it is 1 MSP sensor strength, 1 MSP warhead, 0.01 MSP Fuel and 0.99 MSP Engine).

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Heat-seeker
Missile Size: 3 MSP  (0.15 HS)     Warhead: 4    Armour: 0     Manoeuvre Rating: 10
Speed: 10600 km/s    Endurance: 1 minutes   Range: 0.7m km
Thermal Sensor Strength: 0.25    Detect Sig Strength 1000:  250,000 km
Cost Per Missile: 1.778
Chance to Hit: 1k km/s 106%   3k km/s 30%   5k km/s 21.2%   10k km/s 10.6%
Materials Required:    1x Tritanium   0.25x Uridium   0.278x Gallicite   Fuel x25
Development Cost for Project: 178RPIf this missile is not under shipboard guidance, it will automatically attack any ship with a thermal signature that does not belong to the race that launched it (and when I get started on IFF, maybe that won't be 100% certain). Now lets take three of these missiles and put them in a sensor buoy that will sit quietly for months and then release them when it detects a thermal signature within its second stage separation range.

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Captor Mine
Buoy Size: 12 MSP  (0.6 HS)     Armour: 0
Reactor Endurance: 6 months
Thermal Sensor Strength: 0.25    Detect Sig Strength 1000:  250,000 km
Cost Per Buoy: 6.784
Second Stage: Heat-seeker x3
Second Stage Separation Range: 150,000 km
Materials Required:    3x Tritanium   1x Uridium   0.584x Gallicite
Development Cost for Project: 678RPYou can leave this baby near a jump point (for example) and if someone pops through for a look the buoy will detect them (based on their thermal signature) and if they are within separation range, the buoy will release the three heat-seekers, passing on the location of the target. The heat-seekers (as with any other second stage missile) will head for the target location given to them by the first stage (the buoy in this case) and will starting trying to detect the target themselves. As soon as they do, they home in and attack. I just ran this exact scenario using these mines at a jump point and it worked perfectly. As you can imagine, the possibilities for mine design and mine warfare are considerable. The beauty of it is that it all works under the existing missile rules.

In the course of making these changes I have reviewed and completely overhauled the code used by missiles to select their own targets. In the past they looked for nearby existing sensor contacts. Now when a missile needs to select a target, Aurora runs a complete sensor check for the system using only the missile's sensor. It's much more accurate and much more playable.

One immediate concern I had was that mine warfare could get fiddly as you micromanage launching the mines at various locations around a jump point. Therefore I have added a new fleet order that allows you to fire missiles at a waypoint, jump point or a system body. This order does not require any fire control assignment as the missiles are launched without guidance from the parent ship. In fact, using this order the ship doesn't even need a fire control system. The ship will launch any missiles that are currently assigned to a missile launcher. So if your ship had six launchers and you just wanted to drop off a few solitary sensor buoys, you assign the buoy to one launcher and leave the others unassigned. When the ship reaches a location and carries out the order, only the assigned launcher will drop off a buoy. If you wanted to leave pairs of thermal and EM buoys, assign each type of buoy to a different launcher. Reloading is still a factor so if you try to drop off mines close together the ship will wait until its launchers reload before dropping its mines/buoys and moving on. With this new ability in mind I created a new size 12 missile launcher to lay the captor mines.

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Minelaying System
Maximum Missile Size: 12     Rate of Fire: 360 seconds
Launcher Size: 12    Launcher HTK: 6
Cost Per Launcher: 48    Crew Per Launcher: 120
Materials Required: 12x Duranium  36x Tritanium
Development Cost for Project: 480RPThis is a normal missile launcher designed in the normal way. I just gave it a different name and only bothered with the lowest reload rate. I then created a new Minelayer class using the above system. Note this ship doesn't even have a fire control system or any sensors. It is designed to travel around a set of waypoints you designate and drop off mines (or sensor buoys). In playtesting, it dropped a pair of mines near a ship of another race. The mines immediately detected the other ship and launched their missiles, which homed in and attacked. All of this happened automatically after I gave the drop off order and advanced time.

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Tribal class Minelayer    7000 tons     524 Crew     718.4 BP      TCS 140  TH 160  EM 0
1142 km/s     Armour 1-32     Shields 0-0     Sensors 1/1/0/0     Damage Control Rating 4     PPV 24
Annual Failure Rate: 98%    IFR: 1.4%    Maintenance Capacity 257 MSP    Max Repair 50 MSP
Magazine 1464    

E90 Nuclear Pulse Engine (4)    Power 40    Efficiency 0.90    Signature 40    Armour 0    Exp 5%
Fuel Capacity 150,000 Litres    Range 42.8 billion km   (434 days at full power)

Minelaying System (2)    Missile Size 12    Rate of Fire 360
Captor Mine (120)  Speed: 0 km/s   End: 180 days    Range: 0.1m km   Warhead: 0    MR: 10    Size: 12I am now looking at implementations of the opposite idea. A missiles with a buoy as the second stage. This will allow you to create long-range missiles that deliver a sensor buoy that can remain on station for months or years. It will be a great way to scout out your opponents in a stealthy way. You get the stealthly advantages of recon probes and the long term staying power of ships. I am also looking at putting geological sensors on missiles so you could create a geological sensor buoy, put it on a large first stage missile and fire it at a distant planet to carry out a geological survey. This would also give you the option to provide geological survey probes to non-survey ships and give them a limited surveying capability. I'll post more on these last two ideas once I have done some play-testing.

Steve

[Steve Walmsley (OP)]

To facilitate missiles with buoys as a second stage, any multi-stage missiles fired at a waypoint will release their second stage when they arrive at that waypoint and the first stage will self-destruct. Single stage missiles will remain at a waypoint as they do now. Also, I have added an option to the System Map to place waypoints on the last selected item. This means that if you want to deploy a sensor buoy on a planet, jump point, asteroid, etc. you can place a waypoint on that object and fire a multi-stage missile with a sensor buoy second stage. When it arrives, the sensor buoy will be deployed. You could also deploy mines this way using a three-stage missile with the first stage being the transport and the second/third stages being the mine.

Steve

[ShadoCat]

How about a simplification:

Remove the distinction between missile and buoy.

Give missiles the opportunity to carry reactors.  Thus, the buoy would be self deploying without needing to separate.  It just flies to its destination, stops and does it's job for however many months it has.

A captor mine could be a missile with a reactor and sensors.  It goes to a location (or is dropped at a location) and waits for its sensor to go off.  Then it activates and attacks the target.  

This seems simpler to me.

One option this makes available is a self deploying and self recovering sensor.  Fire it at the target location, it scans for X time and then flies back to its launcher for recovery.  That way, the reactor can be refreshed (whether it uses up consumables or not is up to you).

[Steve Walmsley (OP)]

How about a simplification:

Remove the distinction between missile and buoy.

Give missiles the opportunity to carry reactors.  Thus, the buoy would be self deploying without needing to separate.  It just flies to its destination, stops and does it's job for however many months it has.

A captor mine could be a missile with a reactor and sensors.  It goes to a location (or is dropped at a location) and waits for its sensor to go off.  Then it activates and attacks the target.  

This seems simpler to me.

One option this makes available is a self deploying and self recovering sensor.  Fire it at the target location, it scans for X time and then flies back to its launcher for recovery.  That way, the reactor can be refreshed (whether it uses up consumables or not is up to you).

There are a few reasons I went for the distinction between buoys and missiles in the design stage while treating them both as missiles once designed.

1) I really wanted to avoid creating a new type of object within Aurora with a new set of rules. For this reason, after the design stage there is no difference in game terms between buoys and missiles. They are all just missiles.
2) I didn't want to change the way missiles worked to accomodate mines and sensor buoys because missiles work well at the moment
3) Missiles/Buoys have an endurance. For those with reactors the endurance is based on the reactor life. For those with engines, the endurance is based on the amount of fuel divided by the rate at which fuel consumed by those engines. If missiles were given both engines and reactors then I would have to track two different types of endurance within the same missile, figure out which endurance was being used at any given time and display both endurances to the player.
4) At the moment once you fire a missile its engine remains on until the fuel runs out. There is no way to turn the engine on/off or reduce the thrust if the missile remains in one place. If the missile was to switch between reactor and fuel when it remained in one place, that would mean the engine was turned off and the fuel stopped being consumed. That would have an effect on missiles with no reactors because players would want to know why they couldn't turn the engine/fuel off for those missiles when they halted at a waypoint. This ability would make missiles considerably more dangerous as their non-reactor endurance would effectively be unlimited as long as they remained stationary.
5) There is currently no way for a single-stage missile to know how far away it should engage targets. This means mines could end up wandering around the system chasing fleeting sensor contacts or try to attack a population outside their range. A two-stage missile has a separation range built in which is ideal for players designing mines as they can control at what range the mine will attack.
6) In reality, mines, buoys and missiles are different. There are no self-propelled mines. The US Navy's CAPTOR mine is a stationary object that releases a torpedo when it detects a viable target. The torpedo's own tracking system then takes over. This exactly the same way that Aurora mines will function.

All of the above reasons are why I spent so long trying to figure out a way to handle mines and buoys. I think the idea of separation at design stage but being treated as missiles thereafter deals with all of them

Steve

[Erik L]

Just to clarify a point...

The separation range is the range at which a viable target needs to be before the mine/MIRV releases its submunitions, yes?

[Steve Walmsley (OP)]

Just to clarify a point...

The separation range is the range at which a viable target needs to be before the mine/MIRV releases its submunitions, yes?

Yes. The buoy will still detect objects at greater range but it will only release its sub-munitions if the detected object is within separation range. In addition, the captor part of the mine will continue to use its sensors even after releasing its sub-munitions, acting as an unarmed sensor buoy until its reactor expires and providing an extra target for hostile minesweepers to worry about.

Steve

[Erik L]

Sort of off on a tangent... But since you can fit a weapon into 1 HS (17% GC), and use the remaining .2 MSP (for a size 24 missile) for sensor and reactor; is this something you are contemplating?

[Steve Walmsley (OP)]

Sort of off on a tangent... But since you can fit a weapon into 1 HS (17% GC), and use the remaining .2 MSP (for a size 24 missile) for sensor and reactor; is this something you are contemplating?

Not at the moment, although perhaps some type of one shot beam weapon similar to a Starfire laser buoy might be something for the future. It would have to be in line with the current laser minaturisation tech line that also included enough power for a single blast.

Steve

[Laurence]

How does the targeting work?  Unless I missed something (and maybe I did) it sounds like every mine that can detect an eligble target will fire the moment it sees one.  So sending one ship through to "eat" the mines would clear them out.  

Laurence

[Steve Walmsley (OP)]

How does the targeting work?  Unless I missed something (and maybe I did) it sounds like every mine that can detect an eligble target will fire the moment it sees one.  So sending one ship through to "eat" the mines would clear them out.  

The targeting is based on the separation range of the second stage. If a target is detected within that range, the mine will fire. I don't know if you have played Starfire but I think your question might be based on the ways mine work in that game. in Starfire, you can keep dumping mines near a warp point in limitless quantities. If a ship enters a Stafire minefield, all the thousands of mines somehow talk to one another and decide which ones are going to attack, based on the size of the target. Therefore not every Starfire mine in range attacks.

In reality, you can't do that. Real minefields are spread over an area rather than a Starfire hex and as you move deeper into the field, different mines will attack at different time. If you clump them all together they would all attack the first target at once, which would likely be a waste. In Aurora, you will have to create a minefield much more similar to reality than in Starfire. If you have mines inside seperation range of the jump point they would all attack at once if they all detected the same target. Of course, you could have different settings for different mines. For example, a mine with an active sensor of resolution 100 is going to ignore smaller ships so you could set some mines for small targets and some for larger targets. You could give them an EM sensor so they will only attack targets with active shields. A mine with a weak thermal sensor would only detect targets with a large thermal signature, etc.

You will also have to spread out the field so that ships will be attacked only after they move away from the jump point. You could lay several rings of mines at different distances to achieve this. In fact, in the future I should probably create an ability for you to lay out a minefield pattern and then have the game translate it into waypoints when you select the pattern and a central point. Also, mines won't only be useful at jump points. Leaving mines on obvious shipping routes would be effective, or in the orbits of planets so that the planet and any associated shipping would move into the minefield.

Steve

[Laurence]

Ah, I see.  So design of the mines and they way they are laid will be critical.  Will make it very interesting to deal with or set up fields now.

And yes, my brother and I did play Starfire for years (and that experience did trigger my question), using your software in fact.  :shock:

[Michael Sandy]

I was thinking about anti-missile ship designs, one had lots of box launchers to deliver a huge number of anti-missiles at once, if needed.  But then I thought, how about anti-missile mines?

Have the start stage with the reactor and sensors, and because you might need fairly big stage for the sensors, have it have several counter missiles in its second stage.

You could then have the capacity to quickly deploy enough anti-missile capacity to soak a large volley, if you are talking about protecting a planet from a small mobile force.

[Brian Neumann]

Sandy's post got me thinking about using a bus with submunitions for anti-missile work.  Is there any code currently to keep a missile from being effectivily overflown by it's target.  In this instance I am thinking that a bus would fire it's submunitions, but because the range is fairly close the missiles that were the target of the submunition then overfly the submunitions.  After that the submunitions now have a stern chase to actually catch thier targets, assuming that thier seeker is good enough for the job.

Second question that just came to mind.  If the bus and submunitions do not have any sensors of their own, but are using the fire control of the firing ship, would this make any difference in the equation.

Brian

[Steve Walmsley (OP)]

I was thinking about anti-missile ship designs, one had lots of box launchers to deliver a huge number of anti-missiles at once, if needed.  But then I thought, how about anti-missile mines?

Have the start stage with the reactor and sensors, and because you might need fairly big stage for the sensors, have it have several counter missiles in its second stage.

You could then have the capacity to quickly deploy enough anti-missile capacity to soak a large volley, if you are talking about protecting a planet from a small mobile force.

That's an interesting idea. I don't see any reason why it wouldn't work, although you would need a large first stage to accomodate a powerful enough resolution zero active sensor to spot the missiles far enough away to launch and intercept in time.

Steve

[Erik L]

I was thinking about anti-missile ship designs, one had lots of box launchers to deliver a huge number of anti-missiles at once, if needed.  But then I thought, how about anti-missile mines?

Have the start stage with the reactor and sensors, and because you might need fairly big stage for the sensors, have it have several counter missiles in its second stage.

You could then have the capacity to quickly deploy enough anti-missile capacity to soak a large volley, if you are talking about protecting a planet from a small mobile force.

That's an interesting idea. I don't see any reason why it wouldn't work, although you would need a large first stage to accomodate a powerful enough resolution zero active sensor to spot the missiles far enough away to launch and intercept in time.

Steve

Take a step further... You launch a volley of AM "mines" and a sensor drone. Could the mine submunitions tie into the sensor drone/buoy?