Shields

Shield emitters can be placed around the hull of the ship and depending on the emitter size can generate a shielded area anywhere for 20 metre radius to a 200 metre radius. So a small emitter might be enough to fully encompass a small shuttle but for larger vessels multiple emitters will have to be used. Shields draw a lot of energy, so although having overlapping shield emitters might be attractive the energy draw on the ship could be huge.

Shield emitters come in different sizes, with different maximum power outputs and with different "linking" distances (this allows shields to be linked together if they are within this distance).

The most obvious tactic is for the captain to keep any damaged shields away from the enemy firing arcs, however each of the shields can be boosted, or taken offline for repairs. Shields can also be linked to spread damage with the neighboring shields. Therefore going into combat it might be useful to link shield #8, #1 and #2 together. A hit on shield #1 would be spread between all three shields.

Shields are automatically raised for Yellow and Red alert and automatically lowered for green alert.

Each shield has a strength from 0 to 100%. When the shield strength reaches 0% it has failed. Shields can be boosted up to a maximum of 150% by turning off other shields.

Each shield emitter has a health of 0 to 100%. This is different from the shield strength and relates to the physical damage to the shield generator itself. Damage to the shield generator will reduce the strength of that shield.

For example: For a 1 GigaWatt shield, each percentage of shield strength draws 10MW of power. When the shields is at 100% strength it draws 1,000MW. Shields can be boosted up to 150%, but each percentage above 100% draw 20MW of power. So the front shield could be boosted to 150%, but this would draw 2,000 MW of power.

A maximum of one engineering team can work on each shield generator at a time. i.e. Two teams can be repairing two separate shield generators at the same time, but you cannot put two teams to work on the same shield generator.

Every second that the shield generator is online, there is a 0.1% chance that the shield generator health will drop by 1% due to wear and tear.

Each shield can be linked with up two nearby shields. 25% of the damage hits on these shields will be dissipated to each joined shield. So a hit on shield #1 might inflict 50% of the damage on shield #1, 25% on Shield #8 and 25% on the top shield. Shields can only be linked if they are above 50% strength. If a linked shield collapses, then the excess damage from that second of damage is applied directly to that shield generator. In the above example, if Shield #8 collapsed, then the excess damage from the initial shot will be applied to the Shield #8 generator. Subsequent seconds of damage would not be shared with Shield #8 as it has collapsed. If a linked shield falls below 50%, then the link is broken.

The harmonic frequency of each shield can be set to any number between 200mhz and 500mhz (to two decimal places of accuracy). By default the shields are set to 382.54mhz.

Active shields prevent transporters from beaming in through the shield, with the exception of technologically advanced races who also discover the harmonic frequency of the shield. Note: Transporting can occur through a gap in the shields. i.e. If the shield facing the enemy ship is down, then the enemy could transport troops through the collapsed shield. The ship cannot transport through its own shields. This adds to the strategy of a combat situation if survivors need to be beamed aboard during a battle.

Phaser fire will pass through the shields unaffected if they are set to the same harmonic frequency.

Tractor beams cannot lock on to a shielded target unless the tractor beam is set to the same harmonic frequency.

Power Requirements

Each active shield draws power based up it's size (for example a 1 GigaWatt shield draws 1 GigaWatt at full power). Shields can be deliberately lowered to a lower power rating to conserve power (for example the 1 GigaWatt shield could be reduced to 30% (300 MW) to allow power to be diverted to other shields).

Upgrades

Research allows the shields to be upgraded to increase their maximum power, increase their boost level, increase their recharge rate, increase their range and increase their link distance.

Dev Notes

Shield management is obviously an important part of combat and we want to make it complex enough that skillful use of the shields could make a huge difference to the outcome of the battle.

Shields absorb power from phasers/torpedo blasts at a direct rate of 1 MW per MW impacted. i.e. A 3 second blast with an effective energy of 200MW per second (See phasers) would reduce the shield strength by 600MW. If the shields were at 1,000 MW (100%) they would now be at 400MW (40%).

The health of the shield generators directly reflects the maximum amount of power that a shield can be boosted to and how quickly the shield regenerates.

The formula for maximum shield boost is Health * 1.5. Therefore a shield generator at 80% health can produce a boosted shield up to 120%.

The formula for shield regeneration is Health * 0.1 MW per second. Therefore with an undamaged shield generator it would take 60 seconds for a 400MW shield to repower up to 1000MW (assuming no more damage is inflicted on it). However if the shield generator was itself at 75% it would take 80 seconds for the shield to regenerate to 100%.

Repairs to a shield generator are much slower if the shield is online. 

I know that in Star Trek Generations the Klingons fired a photon torpedo through the Enterprises Shield by matching the shield harmonics – but I’m going to ignore that as it wouldn’t really make sense.