Quick Vehicle Write-Up Rules

[Atgxtg]

I just uploaded the latest version of my Quick Vehicle Write-up rules for BRP to the files section.

While still a work in progress, it should be possible to write up a real world vehicle with it and get stats consistent with the BRP rules (at least with BRP Zero).

[rust]

Again, thank you very much - especially for the Swiftsure submarine, which
provides an excellent design example for my water world setting.

I was looking for the Vehicle Design Rules and Vehicle Modification Rules (both
version 4.1) you mentioned in your file, but unfortunately I seem unable to
find them ?

Thank you !

[Atgxtg]

Originally Posted by rust

Again, thank you very much - especially for the Swiftsure submarine, which
provides an excellent design example for my water world setting.

Hey somebody actually reads this stuff!

Originally Posted by rust

I was looking for the Vehicle Design Rules and Vehicle Modification Rules (both
version 4.1) you mentioned in your file, but unfortunately I seem unable to
find them ?

Not finished yet. Both are a bit more complicated than writing up something already exists, since you need to work out it's performance data first. I suspect the mod rules will be ready next, but won't be of much use until the design rules are done.

But, for what it's worth, it looks like +1 point of STR is worth a 9.05% increase in MOV and top speed. Upping a vehicle's STR will be similar to training a stat only it will require a character to make a difficult skill roll and have a 5% penalty per point already improved.

Supers have it easier, as they can just opt to spend Hero creation points on the vehicle's STR.

Originally Posted by rust

Thank you !

You're welcome. It's still needs work, but I figured if it was up I'll get feedback and see what needs to be fixed.

[rust]

Originally Posted by Atgxtg

Not finished yet.

Well, there is at least one reader waiting for that stuff ...

Edit.: I have used your system for some calculations for both real world vehicles
(e.g. the research submarine Alvin) and science fiction vehicles (e.g. a re-
search submarine I designed with GURPS Vehicles), and your system is doing
very well.
To give an example: Alvin has a safe depth of 4,500 m, which according to
your formula would require 32 AP. The real vehicle has a hull of 50 mm of ti-
tanium, which would give it an AP 27 on your table - quite close enough for
my purposes, especially since Alvin is a small vehicle with a pressure-resistant
form, which helps to absorb pressure and reduces the need for armor at least
somewhat.
Your system did even better with my science fiction submarines, which have
more conventional forms, and I am now looking forward to using it with anti-
gravity vehicles and spaceships.

[threedeesix]

HIT POINTS: A vehicle's Hit Points are equal to one-half the Vehicle’s SIZ. Note that this is actually the same as character's (CON+SIZ)/2, except the vehicles don't have a CON attribute.

Actually, this isn't like is done in BRP. Hit Points should be equal to SIZ, not 1/2. Otherwise a SIZ 32 giant will have more HP than a SIZ 32 vehicle. Skeletons for instance have no CON but use their full SIZ as HP.

This looks awesome though and I plan on using it tonight to stat up some vehicles. You have proven that BRP can be crunchy.

Nice job.

Rodney Leary

[Atgxtg]

Originally Posted by threedeesix

Actually, this isn't like is done in BRP. Hit Points should be equal to SIZ, not 1/2. Otherwise a SIZ 32 giant will have more HP than a SIZ 32 vehicle. Skeletons for instance have no CON but use their full SIZ as HP.

Did you DL version 4.2? Or the much older version 3.0 design rules that predated zero? In the Quick Write UP rules Hit Points iare equal to a vehicles SIZ+a modifier for vehicle type.

This looks awesome though and I plan on using it tonight to stat up some vehicles. You have proven that BRP can be crunchy.

Thanks but get the Quick Write up rules. They are much easier to use, and it is a lot easier to modfiy something once you have something to modify.

As for BRP. Well, Superworld was crunchy, ans was RQ, so BRP being a "lite" easy game is more removing the crunch that was there.

Nice job.

Rodney Leary

Thanks. I'll try to update the other stuff (design and modification rules) as well as this nice BRP is released and I can see what changes in the final version.

[threedeesix]

Originally Posted by Atgxtg

Did you DL version 4.2? Or the much older version 3.0 design rules that predated zero? In the Quick Write UP rules Hit Points iare equal to a vehicles SIZ+a modifier for vehicle type.

Oops, downloaded the wrong one. Just downloaded the 4.2 ver. Nice formatting.

Thanks. I'll try to update the other stuff (design and modification rules) as well as this nice BRP is released and I can see what changes in the final version.

Can't wait to see it. Looks great so far.

Rod

[Atgxtg]

I was pleasantly surprised with how the "Tumbler" came out. I was going to include the Space Suttle Orbiter as the "push the envelope" sample case, but it was just so different from most other vehicles in game terms (MOV is high, but is all gained through launch, things like specfic impulse and delta-v are not common design elements for 99.99999% of vehicles in RPGs).

The modification rules should allow you to turn a production model vehicle into whatever you want. I just need to get a look at how the Powers are worked out compared to Superworld. What I'm trying to do with it it:

1) Rate vehicle Engines in terms of STR, and maybe give that a valeu in horsepower. Then allow characters to up the engine's performance by upping it's strength. Each +1 STR would be a 9.05% increase in MOV, or so. I need to look at it a bit more closely but the idea is that +8 STR is double the power, as with the old SIZ chart.

Speaking of SIZ I need to update the Quick rules SIZ chart for SIZ scores under 30. So motorcyles won't come out quite right yet. Got to add handling for subs, hovercraft and airships, too.

2) Add armor. Either by trading off performace for AP (the weight) or by the supers rules. Super vehicles basically get to bypass the real world pysics stuff when a character spends some heation creation points. So a Batmobile can have APs like an APC and the performace of a spotscar.

3) Add weapons. Either by spending money to buy and mount them, and/or as a buy with "Hero creation" points like in old Superworld, with a weapon costing points equal to it max damage. Will need to give weapons a base range based on the damage die and a cost adjustment for increasing reducing the range. In theory a 6 point/1D6 weapon will have the base range of a light pistol, an 8 point/1D8 weapon would have the range of a medium pistol, and so forth up the scale.

A shift in range would probably be a +2 "range steps" per point, so you could give a medium (1D8) pistol the range of a heavy (1D10+2) pistol with a point. Likewise some sort of saving for reducing the range. Probably -1 per 2 range steps, with a cap of half the cost, and a min. cost of 1.


4) Add in some other abilities, mostly by using the powers system with a few tweaks to fit vehicles.

[rust]

@ Atgxtg:

I seem to have a minor problem with the way the Hit Points are determined.

My colonists built the same vehicle twice, a prototype with a steel hull and
an improved version with a hull made of composites. Since the one with the
steel hull is considerably more heavy, it has a higher SIZ score, and there-
fore more Hit Points - but otherwise it is exactly the same vehicle, even the
AP values are identical (due to a somewhat thicker hull on the improved ver-
sion).

This is nothing serious in the case I mentioned, but I could imagine that it
could become more of a problem with truly huge vehicles, when lightweight
materials will make a really significant difference in weight / SIZ, but not
much difference in AP: The more modern vehicle would be less able to ab-
sorb damage, for no obvious reason.

Or did I overlook something, or get something wrong ?

Thank You !

[Atgxtg]

Originally Posted by rust

@ Atgxtg:

I seem to have a minor problem with the way the Hit Points are determined.

My colonists built the same vehicle twice, a prototype with a steel hull and
an improved version with a hull made of composites. Since the one with the
steel hull is considerably more heavy, it has a higher SIZ score, and there-
fore more Hit Points - but otherwise it is exactly the same vehicle, even the
AP values are identical (due to a somewhat thicker hull on the improved ver-
sion).

This is nothing serious in the case I mentioned, but I could imagine that it
could become more of a problem with truly huge vehicles, when lightweight
materials will make a really significant difference in weight / SIZ, but not
much difference in AP: The more modern vehicle would be less able to ab-
sorb damage, for no obvious reason.

Or did I overlook something, or get something wrong ?

Thank You !

No you got it right. It's not entirely unrealistic either. Heavier vehicles have more mass which translates into more HP. Since the scale is a doubling one, number will be compressed a bit, too.


I did the quick rules with the idea of modern vehicles in mind, so a futuristic design might have a bigger "add" to the hit points, too. For instance if a Vintage Tank's HP=SIZ+5, and a Modern One SIZ+50, a Futuristic "Tank" might be +95, or +75, or +120, depending on just how far in the future we are talking about. But that's a bit beyond what is in the BRP core.

So if you got an advanced sub in a futuristic setting with a composite hull, that +100 to Hit points might be higher.



BTW, how did you build the sub's hull with the lightweight one? I suspect that a sub hull made out of lightweight material would probably be a thicker than a steel hull, and get back some of the weight.

And... how are the Handlling numbers looking?