Proposed - Battlesuits should be treated as Vehicles

[Joseph Paul]

..and so should self powered exosuits and walkers.

Often we have the vision of these as being Juggernauts of futuretech rage and the only way to stop them is to wound or kill the operator. Those machines pack a lot of systems under the armor any one of which could be disrupted enough to cause 'mission kills' of the unit with out harming the operator (too much...). How to simulate that in GURPS? I am thinking that a battlesuit specific vehicle hit chart gets used giving the chances of affecting the suit first and then the wearer. Setting assumptions affect how discrete major systems are vs how distributed and the redundancy and self-repair capability of the suit if any.

Here is a list of what I think the Major Systems are and the likely effects of disrupting/damaging them.

Power - Things shut down pretty quickly. OTOH you might want a power plant hit to give some minutes of power before it gives up the ghost.

Life Support - Hopefully for the shooter a life support hit will spill air or do something that will keep the trooper much more interested in fixing his machine than chasing her. Rapidly falling pressure may fog things I think. If not it can be racked up as more trouble that needs to be fixed. Breaiking fluid lines/reservoirs in the suit would be interesting especially in freefall.

Computer Functions - realistically this should be redundant or distributed at later tech levels. However UT only issues one so if you can hit it the loss should be disastrous to the suit and wearer. It could take out any of the other systems that rely on digital info to work.

Communication - Either can't send or receive or both. If it can't receive and mapping functions are provided by satellite then the trooper is going to have a hard time getting home. Better yet she can't call for help.

Frame - The actual structural elements of the suit. It could be a jointed stickman configuration or the armored elements double as frame members. Hurting a limb so badly that it can't function will mess up any mobile infantryman's day. Reduced move, reduced BL, reduced range of motion are all possibilities.

Joints - Losing joints will limit mobility or the ability to interact with weapons and terrain. Controls and power conduits for joints are probably wired separately so losing one probably won't cause a cascade failure. However being able to move the ankle but not the knee is little solace. This has a good chance for a mobility 'kill'. Leg'em and leave'em.

Powertrain - Air/hydraulic/electric - Lots of tubing/hose/wires to clip with a round just passing through. Myomer and other 'muscles' may get cut or have an attachment point destroyed. Reduced move and range of motion should result. If the motor for the leg is out the trooper inside probably is stuck.

Weapons - Yeah just breaking those exposed weapons would be good.

So going this route mandates having an equipment list for the suit that has all the HT and HP and DR for the components. Easy enough to do.

Setting the odds of damage to the suit causing the destruction or malfunction of systems needs to be set also.

Anything else?

[Tyneras]

For more form-fitting armor, having a "X in 6" chance of hitting and disabling a system if that location is penetrated would be a quick and dirty way of doing it. Would also work for high/ultra tech body armor.

Another way would be to track battle suit HP separately from the wearer and use the Overpenetration rules (Basic p.408) with HT rolls for the suit to determine if/when a system fails.

[weby]

In general it depends a lot on the suit and I personally do not much care for the vehicle hit chart in the basic set, I am much more a fan of the Space ships approach to being hit.

A SM +0/20 lb nanosuit or 30 lb Cybersuit will be very different than a SM +2/800lb combat walker. In the smaller suits it is very hard to penetrate the suit without hitting the occupant, but in a combat walker it is much easier.

I have used the normal human hit chart for hits to battle suited troops and mechas. After the hit on the hit location chart I have used an additional sub location roll to determine what is hit.

It should be noted that I use the same methodology for non powered armors with integrated systems like space suits and space armor.

My table for light suits(basically cybersuits/vacsuitss and similar) is: 1-5:occupant hit 6:equipment hit.

Medium suits(basically the Powered Combat Armor/Commando Battlesuit/Space armor with exoskeleton and similar): 1-4:occupant hit 5-6:equipment hit

Heavy suits(Heavy Battlesuit and other SM 1 suits):
1-3:occupant hit 4-6:equipment hit

Light walkers(SM 2 combat walkers and similar): 1-2:occupant hit 3-6:equipment hit.

Heavy walkers(SM 3 combat walkers and similar): 1:occupant hit 2-6:equipment hit. (These are the largest vehicles with the occpant legs partly in the legs and arms in arms)

Light mecha(SM 4): The drivers is hit on 1-2 on torso, else it is equipment hit.

Medium mecha(SM 5)/Heavy mecha(SM 6): The driver is hit on 1 on torso, else it is equipment hit.

In all cases I have notes made of the listed gear as to what hit location they are in. After the equipment in question is hit then on remaining damage I roll if the extra damage continues inside (1-4 on d6, or not: 5-6) if continued inside I roll again on the same chart as originally.

[Humabout]

Originally Posted by Joseph Paul

..and so should self powered exosuits and walkers.

I believe this is how they were designed in GURPS 3ed Vehicles. This doesn't sound terribly unreasonable except that if the operator must physically move all of his limbs as if he's the one walking and such, standard combat maneuvers should still be used. The vehicle doesn't move independently of the operator, since the operator has to still walk/run/jump/whatever himself. Otherwise, I'd mine Vehicles for ideas before moving on.

[Anthony]

The traditional form-fitting battlesuit is small enough that you're not very likely to disable the suit without also disabling the occupant, though larger mechs certainly could be.

[ericthered]

Originally Posted by Anthony

The traditional form-fitting battlesuit is small enough that you're not very likely to disable the suit without also disabling the occupant, though larger mechs certainly could be.

I can see an argument for a "rolling expansion" where as they get bigger you're more and more likely to hit just the suit though.

[Tyneras]

Size difference between the suit and the wearer is probably a key point.

SM difference of 0 is body armor, even with lots of extra systems it can still be treated as a direct extension of the wearer.

SM difference of 1 to 3 is where things get fuzzy.

SM difference of 4+ gets into GURPS Spaceships rules (for human sized critters, at least) and can probably use those rules directly for damage to systems.

Edit:
Using the 3:1 per SM rule from Spaceships, assuming that a SM +4 pilots compartment is as small as practical, then at SM +3 the pilot would be 3 systems in size, SM+2 9 systems, and SM+1 27 systems. Obviously the system breaks at some point, but I can't recall if there's a "super compact form fitting cockpit" option and I don't have my kindle with me so I can't check my library.

[GodBeastX]

With current vehicle design, I disagree that suits should be treated as vehicles anymore than roller skates.

My feeling is if my body fills every location so as to act as the HP of said vehicle, then it isn't a vehicle, it's equipment.

As for damaging internal mechanics, I wouldn't turn it into a vehicle to do it. I would come up with some other method. Maybe systems roll HT as HP is lost if the body part that contains them takes injury.

[ericthered]

Pyramid 40 gives a seat component at SM 3 to be one seat with no life support. I'm not sure if the control station technically includes a seat or not, but I suspect it doesn't.

So that means that the seat can be squished down to 9 slots in an SM+0 vehicle. An interesting result to be sure, leaving little room for a control room and armor.

[The_Ryujin]

My 2¢ on this is if it's bigger the Operators SM by +2 or more it's a Mecha and they are already treated as vehicles (they might warrant a max of +3 if they are really bulky).

For battlesuit, if you want to track damage then figure HP from weight. For SM 0 suits they're just to small offer cover DR to the operator (they're effectively thin walls) and in fact there should only be about a 2 in 6 chance of the suits frame getting hit. For SM +1 suits they might be thick enough to offer cover DR and there is a larger chance that the suit will be hit, about 3 in 6. For a SM +2 or +3 suit then they can probably be treated as borderline mecha and all hits will hit the frame and you could either treat the suits HP as DR and anything that gets past that hits the operator or you could just use the occupant injury rules instead.