Fire, Fusion and Steel addenda
Sensor Options and Exotic Sensors
by
bmac@astro.ucla.edu
Sensor Options
High or Low-powered active sensors
Active sensors may be designed to trade off
required input power for size - achieving greater sensitivity in a
small package by use of a higher-powered beam, for example. High-power
active sensors of a given sensitivity have the price as a normal
sensor of the same sensitivity, but the designer may decrease the
surface area by any factor between 2 and 5, increasing the power
consumption by the same factor. High-power sensors have a volume
of 10m3 per m2 of area.
Similarly, low-power active sensors decrease
the input power by a factor of 2 to 5, increasing the surface area
by the same amount. Low-power sensors have a volume of 2.5 m3 per m2
of area.
Continous sensor formula
Mathematically inclined users can calculate the
area of sensors of arbitrary sensitivity by using the following formula:
Area = Base Area * 100 ^ (sensitivity-13)
(the ^ signifies exponentiation.)
The base area is found on the following table:
TL | PEMS base area | AEMS base area
|
---|
8 | | 50,000
|
9 | | 1,000
|
10-11 | 2 | 5,000
|
12-13 | 1 | 2,500
|
14-15 | 0.5 | 1,000
|
The minimum diameter and firing range (for PEMS) is taken from the nearest
PEMS on table 198 in Fire, Fusion and Steel. Sensors may not be
constructed with greater or lesser sensitivity than those on Table 198
and Table 201 at a given TL.
Exotic Sensors
There are three types of exotic sensors
available: Neutrino sensors,
Gravitic Sensors, and Neural Activity Scanners.
Neural Activity Scanners
Neural Activity Scanners detect and classify
life forms based on brain activity. They are extremely short-ranged,
expensive, and fragile. At each TL two basic models are available -
a lightweight (portable) model and a somewhat larger ranged device.
TL | Range | MW | Vol | MCr
|
---|
13 | 0.010 | 0.004 | 0.002 | 0.02
|
13 | 0.100 | 40.0 | 50.0 | 20.0
|
14 | 0.050 | 0.005 | 0.002 | 0.02
|
14 | 0.200 | 50.0 | 50.0 | 20.0
|
15 | 0.100 | 0.006 | 0.002 | 0.02
|
15 | 0.400 | 60.0 | 50.0 | 20.0
|
Range: Typical range in km
MW: power required in MW
Vol: volume in m3. All NAS mass 2 tonnes per m3
Antenna area (m2) = MW x 100
Neutrino Scanners
Neutrino scanners attempt to detect neutrinos
emitted by nuclear power plants. Pracitcal high-efficiency neutrino
sensors are made possible by the increasing mastery of nuclear forces
at TL12; however, they are generally too short ranged to be useful in
starship combat. In addition, they function only as scanners -
dececting targets but not providing a precise enough position for fire
control. Neutrino scanner volume is given by the following table:
Sensitivity | Volume at TL12-13 | Volume at TL14-15
| Typical Range
|
---|
8 | 10.0 | 5.0 | 50 km
|
8.5 | 50.0 | 20.0 | 160 km
|
9 | 500.0 | 200.0 | 500 km
|
9.5 | 50000.0 | 20000.0 | 1600 km
|
Neutrino scanners mass 2 tonnes per m3 and cost MCr 5/m3. They require
0.1 MW per m3. They require no surface area.
For detection purposes, neutrino signature can
be calculated by totalling the power of all nuclear
(fusion, fission, and fusion+) power plants on the vehicle and comparing
to table 13. At TL13+, power plants can be constructed with neutrino
shielding. Neutrino shielding requires 0.1 m3 per m3 of power plant
volume, masses 1 tonne per m3, cost MCr 1.0 per m3 and require 0.01 MW
per m3, and reduces the neutrino signature by 1.0.
Gravitic scanners
Gravitic scanners detect both static
gravitational fields and gravitational radiation. The ability of grav
sensors to detect static fields is limited to strong fields or
anomalies such as those caused by large mineralogical anomalies, or
large astronomical objects. Their ability to detect graviational
radiation, however, gives them some sensitivity to the gravity waves
produced by thruster plates and contra-grav propulsion. Like neutrino
scanners, they are not accurate enough to provide a fire-control
solution, and are somewhat short-ranged.
Despite the impressions of certain science-fiction authors, gravitational
radiation travels only at the speed of light.
Gravitic scanner volume is given by the following table:
Sensitivity | Volume by TL12-13
| Volume by TL14-15
| Typical Range
|
---|
7.0 | --- | 0.01 | 5 km
|
7.5 | 0.5 | 0.05 | 16 km
|
8 | 5.0 | 0.50 | 50 km
|
8.5 | 100.0 | 5.00 | 160 km
|
9 | 5000.0 | 100.0 | 500 km
|
9.5 | 500000.0 | 2000.0 | 1600 km
|
10.0 | --- | 200000.0 | 5000 km
|
Mass is 2 tonnes per m3. Price is MCr 8 per m3. Power required is 0.01 MW
per m3. Antenna area is 0.5 m2 per m3.
Gravitic sensors operating on a planetary
surface or on a ship with active thruster plates have their
sensitivity reduced by 0.5
The gravitic signature of a vehicle may be
calculated from the following table:
Thrust (kn) | Signature
|
---|
1 - 10 | -2.0
|
10 - 100 | -1.5
|
100 - 1,000 | -1.0
|
1,000 - 10,000 | -0.5
|
10,000 - 100,000 | 0.0
|
100,000 - 1,000,000 | 0.5
|
1,000,000 - 10,000,000 | 1.0
|
10,000,000 - 100,000,000 | 1.5
|
100,000,000 -1,000,000,000 | 2.0
|
(As a rule of thumb, thrust in kn = (G-rating)*(size in Td)*(100.)
Vehicles propelled by contra-grav instead of thruster plates have
their signature reduced by 0.5.
© 1997 bmac@astro.ucla.edu. Traveller is a trademark of Imperium Games.
Permission granted to reproduce electronically on the World Wide Web.
Permission is *not* granted to Imperium Games to reproduce this text in any
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