Blunt Trauma

JazzJedi · 04-19-2018, 11:10 AM

I've been playtesting a hack I made to simulate blunt trauma and thought I would share. For years, I used T-bone's Edge Protection rule, but I found this unsatisfactory for ballistic armor with trauma plates and other rigid armor especially with high DR ultratech armors, such as TL 10 Combat Hardsuit (DR 75) which would convert to DR 60 EP 25. This means that there is no blunt trauma from the first 60 points of damage, which doesn't seem realistic to me.

So I came up with a new way of simulating blunt trauma that uses a similar system to the RAW but modifies the amount of damage it takes to get 1 point of injury from blunt trauma. It has the complication of adding a Blunt Trauma (BT) rating to body armor. This handily eliminates the need for the distinction between flexible and rigid armor, which makes sense. Most "rigid" armors are flexible and dent and deform quite a bit when struck. They don't spring back to their original shape, but they still convey blunt trauma through them, before they are penetrated.

For every full multiple of an armor's BT you take of crushing, cutting, impaling, or piercing damage you suffer 1 HP of injury due to blunt trauma.

BT eliminates the need for the distinction between flexible and rigid armor, as these exist on a spectrum anyway. Most flexible armors have a BT equal to 1/6 to 1/4 of its DR, or 1/2 to 1/3 for most rigid armors. The minimum BT is 1, which means that the armor offers no protection from crushing damage and converts the other forms of damage into crushing. This is appropriate for light mail and thin cloth armor.

I based the BT ratings partly off the NIJ standard, where the deformation a projectile creates upon impact cannot exceed 44mm (1.73 in.). A penetration of 44mm is known to cause broken ribs and internal bleeding and possible death, this must be close to a major wound, which is 5-6 points of damage for an average person with 10 HP. So a BT equal to 1/5 DR means that if an attack does damage equal to the armor's DR, the target will take 5 points of blunt trauma. I know that armor can deform considerably more than this before being penetrated, but the math is not linear anyway, and this is just a rough approximation for playability.

You could even split the BT rating to cover different damage types.

Some Examples:
TL2 Light Mail is DR 6, BT 1
TL4 Medium Plate is DR 12, BT 4
TL8 Assault Vest is DR 15, BT 3
Trauma Plates add +25 DR (semi-ablative), +5 BT (1/5 of DR)
TL10 Combat Hardsuit: DR 75, BT 15

I put up more examples on my webpage, but this idea has not been fully fleshed out or extensively playtested. Any feedback would be welcome.

04-19-2018, 11:10 AM	#1
JazzJedi Join Date: Dec 2014	Blunt Trauma I've been playtesting a hack I made to simulate blunt trauma and thought I would share. For years, I used T-bone's Edge Protection rule, but I found this unsatisfactory for ballistic armor with trauma plates and other rigid armor especially with high DR ultratech armors, such as TL 10 Combat Hardsuit (DR 75) which would convert to DR 60 EP 25. This means that there is no blunt trauma from the first 60 points of damage, which doesn't seem realistic to me. So I came up with a new way of simulating blunt trauma that uses a similar system to the RAW but modifies the amount of damage it takes to get 1 point of injury from blunt trauma. It has the complication of adding a Blunt Trauma (BT) rating to body armor. This handily eliminates the need for the distinction between flexible and rigid armor, which makes sense. Most "rigid" armors are flexible and dent and deform quite a bit when struck. They don't spring back to their original shape, but they still convey blunt trauma through them, before they are penetrated. For every full multiple of an armor's BT you take of crushing, cutting, impaling, or piercing damage you suffer 1 HP of injury due to blunt trauma. BT eliminates the need for the distinction between flexible and rigid armor, as these exist on a spectrum anyway. Most flexible armors have a BT equal to 1/6 to 1/4 of its DR, or 1/2 to 1/3 for most rigid armors. The minimum BT is 1, which means that the armor offers no protection from crushing damage and converts the other forms of damage into crushing. This is appropriate for light mail and thin cloth armor. I based the BT ratings partly off the NIJ standard, where the deformation a projectile creates upon impact cannot exceed 44mm (1.73 in.). A penetration of 44mm is known to cause broken ribs and internal bleeding and possible death, this must be close to a major wound, which is 5-6 points of damage for an average person with 10 HP. So a BT equal to 1/5 DR means that if an attack does damage equal to the armor's DR, the target will take 5 points of blunt trauma. I know that armor can deform considerably more than this before being penetrated, but the math is not linear anyway, and this is just a rough approximation for playability. You could even split the BT rating to cover different damage types. Some Examples: TL2 Light Mail is DR 6, BT 1 TL4 Medium Plate is DR 12, BT 4 TL8 Assault Vest is DR 15, BT 3 Trauma Plates add +25 DR (semi-ablative), +5 BT (1/5 of DR) TL10 Combat Hardsuit: DR 75, BT 15 I put up more examples on my webpage, but this idea has not been fully fleshed out or extensively playtested. Any feedback would be welcome.