GURPS Spaceships Design Spreadsheet

[ericbsmith]

Originally Posted by DaltonS

I need a little clarification on “Modular Sections” (RC10). I know there is something about modular systems in the Spaceships books, and I can using these rules for Small or Tiny modular sections, but the larger sizes might have different rules.

This was my attempt to design something like the Modular Cutter from GURPS Traveller. Many of the questions you asked would depend on how, exactly, the ship is designed, but normally a module would be designed to fit a specific ship or a specific universe (such as Traveller) might have a standardized module size that all modules would conform to. How the performance, the Modular Cutter itself doesn't get any real performance benefits from not having the module installed because the module serves as part of the structural reinforcement; without a module in place it can't accelerate any faster as it would risk breaking it's back in such a maneuver.

Originally Posted by DaltonS

This implies that the ship can function without the modules. After dropping a Standard or Large modular section, the ship's mass is reduced one or two thirds. Does this affect the ship's STL and FTL space performance? Does the reduced volume affect shield dDR?

Performance may increase, but it may not as there may be inherant limits to the systems or the ship's design. I wouldn't change dDR; the shape of the ship isn't changing, neither is the thickness of the armor. There's no reason dDR would change.

[DaltonS]

Originally Posted by ericbsmith

This was my attempt to design something like the Modular Cutter from GURPS Traveller. Many of the questions you asked would depend on how, exactly, the ship is designed, but normally a module would be designed to fit a specific ship or a specific universe (such as Traveller) might have a standardized module size that all modules would conform to. How the performance, the Modular Cutter itself doesn't get any real performance benefits from not having the module installed because the module serves as part of the structural reinforcement; without a module in place it can't accelerate any faster as it would risk breaking it's back in such a maneuver.

That's what I thought. (Glad it wasn't from some Pyramid article I'd missed.) I think a rational supposition would be performance might increase if a Large or Front Standard Module was detached from a single forward facing surface, but not if a Center Standard Module was deployed due to the structural concerns of connecting front and rear sections.

Originally Posted by ericbsmith

Performance may increase, but it may not as there may be inherant limits to the systems or the ship's design. I wouldn't change dDR; the shape of the ship isn't changing, neither is the thickness of the armor. There's no reason dDR would change.

Ah, but I was talking about Force Screens, not armour. I suppose this would depend on whether the screen was spherical or conformal and the ship's general shape; if the overall length of the ship was reduced, a spherical screen could apply its energy to a smaller surface area thus increasing dDR, while if the screen was conformal, it would depend on the ratio of exposed surface areas with/without the module.

Dalton “who had his own ideas, but wanted to check yours first” Spence

[ericbsmith]

Originally Posted by DaltonS

That's what I thought. (Glad it wasn't from some Pyramid article I'd missed.)

Everything described in the Optional Rules is my original creation, with the exceptions being the Escape Pod, Drop and Stealth Capsules (which came from the Designers Notes) and the Vehicle Dock which was nipped from RPK's Traveller rules and included mostly because of the complexity of the rules covering it. There are a lot of rules there that are modifications of older rules, such as Cargo Hold Collapsible Fuel Tanks, but those come indirectly from 3e material and needed rewriting for the Spaceships rules. Even the pods needed some redesigning, as the original designers notes allowed them to be fired from a 32cm (12 inch) missile launcher. I don't know about you, but firing a 4-man escape pod through a 32cm missile tube sounds like a good way to spaghettify the occupants.

Originally Posted by DaltonS

I think a rational supposition would be performance might increase if a Large or Front Standard Module was detached from a single forward facing surface, but not if a Center Standard Module was deployed due to the structural concerns of connecting front and rear sections.

That sounds pretty reasonable. However, keep in mind that the original Traveller Modular Cutter basically had a Large Module. It just had a forward command deck which helped clamp the modules in place, but by weight it was at least 50% module (up to 70% depending on the exact module) and by volume 60%.

There are also concerns about detaching small or tiny modules. A ship can carry a number of these and detaching a number of them can compromise structural integrity, making it difficult to do high acceleration maneuvers.

Originally Posted by DaltonS

Ah, but I was talking about Force Screens, not armour. I suppose this would depend on whether the screen was spherical or conformal and the ship's general shape; if the overall length of the ship was reduced, a spherical screen could apply its energy to a smaller surface area thus increasing dDR, while if the screen was conformal, it would depend on the ratio of exposed surface areas with/without the module.

I'd missed that you were talking about Force Screens. I would say that dDR doesn't change unless you have the Adjustable option on the screens, in which case you can Adjust the screens away from the part of the ship that is no longer there to reinforce the part that is. I'd probably allow x1.5 dDR across the two remaining sections if a Standard module is detached; x2 dDR across the remaining section if a Large module is detached (the later is basically the default rule).

[DaltonS]

Originally Posted by ericbsmith

Everything described in the Optional Rules is my original creation, with the exceptions being the Escape Pod, Drop and Stealth Capsules (which came from the Designers Notes) and the Vehicle Dock which was nipped from RPK's Traveller rules and included mostly because of the complexity of the rules covering it. There are a lot of rules there that are modifications of older rules, such as Cargo Hold Collapsible Fuel Tanks, but those come indirectly from 3e material and needed rewriting for the Spaceships rules.

Wow! Impressive. Maybe you should collect a list of your optional spreadsheet rules with commentary and write them up as a Pyramid article about 3e Vehicle to 4e Spaceships conversions. If you like 3e systems adapted to Spaceships, see my translation of the VE2 Gravity Screen.

Originally Posted by ericbsmith

Even the pods needed some redesigning, as the original designers notes allowed them to be fired from a 32cm (12 inch) missile launcher. I don't know about you, but firing a 4-man escape pod through a 32cm missile tube sounds like a good way to spaghettify the occupants.

Can you say “Ouch!”? |;-/

Originally Posted by ericbsmith

That sounds pretty reasonable. However, keep in mind that the original Traveller Modular Cutter basically had a Large Module. It just had a forward command deck which helped clamp the modules in place, but by weight it was at least 50% module (up to 70% depending on the exact module) and by volume 60%.

But it looked cool, right? That's the important thing, not the engineering realities. Okay, I'll put it on my list of things to discuss with Mark and Loren on my next trip back to the '70s. ;)

Originally Posted by ericbsmith

There are also concerns about detaching small or tiny modules. A ship can carry a number of these and detaching a number of them can compromise structural integrity, making it difficult to do high acceleration maneuvers.

This looks very situational, and would depend on a whole bunch of factors (including the style of the game session). More work for the GM, I guess.

Originally Posted by ericbsmith

I'd missed that you were talking about Force Screens. I would say that dDR doesn't change unless you have the Adjustable option on the screens, in which case you can Adjust the screens away from the part of the ship that is no longer there to reinforce the part that is. I'd probably allow x1.5 dDR across the two remaining sections if a Standard module is detached; x2 dDR across the remaining section if a Large module is detached (the later is basically the default rule).

That is pretty much as I figured, although I'd missed needing the Adjustable option to change the shield's shape. Good call, that.

Dalton “who is glad he asked his questions” Spence

[ericbsmith]

Version 2.0 Release Candidate 11
This is another Excel only release. However, keep in mind that much of the work on Macros has been to eventually improve OpenOffice performance, compatibility, and ease of conversion.

-Significant improvements in Macro execution speed in Excel; These improvements will eventually be incorporated into the OpenOffice version, and help there as well.
-Updated all Quantity drop-down selections to accept user input as well as drop-down selection. That is, if you want to input 99,999 this is not available in the drop-down but if you manually input the value it will be accepted if it is otherwise valid (e.g. you can actually install 99,999 in that location). This applies to most sections of the sheet, including the Crew breakdown section, as well as Auxiliary Craft, Cargo Hold, Habitats, Open Spaces, and Weapons sections.
-Moved Space Combat Turn Length and Range Scale to Campaign Options. Will be saved, loaded, and reset as a Campaign Option from now on, and will import setting from older ships as needed.
-Added Campaign Option for Slower Industrial Systems
-Added Ship Options for No Computers, Pre-Radio, and Zombie Ship to the Ship Options: Spaceships 7 section.
-Various UI tweaks, including section jump buttons for the Optional Rules, Campaign Options, and User Systems pages.
-More garage vehicle options, with new Passenger variants (the vehicles exclude most cargo capacity for more passenger capacity).
-Improved search capabilities in the Saved Ships sheets.
--You can now search up to five words or phrases. You can search for a phrase by substituting spaces with underscores. For instance, searching for "Utility_Truck" will search for ships with the entire phrase "Utility Truck" where as if you search for "Utility Truck" it will return any ships which contain either "Utility" or "Truck."
--You can now check a box to search for all ships of the chosen TL or below. For this purpose if you choose a superscience TL then both superscience and non-superscience TL's equal or lower will be included. Ships with a divergent TL, such as TL4+3, will add the two numbers together to determine what effective TL they are; so TL4+3 would be treated the same as TL7.
--You can now search multiple SM of ship; there are two SM entry fields, if you enter a value into both then any ships that fall between the two values will be shown. For split SM ships if either value falls within the search criteria the ship will be shows. So a SM+6/+7 ship will show up in a search of SM+5 to SM+6, and will also show up in a criteria of SM+7 to SM+9.
-Fixed bug where Water Performance for Oars and Sails weren't displayed.
-Fixed bug where damage wasn't correctly calculated for some weapons when using the Square Root of Destruction option.
-Various other bug fixes


Excel 2000 RC11
http://gurpsland.no-ip.org/zip/SpaceshipsV2.zip (3.7MB)
http://gurpsland.no-ip.org/zip/SpaceshipsV2.7z (1.8MB)

Excel 2007 RC11
http://gurpsland.no-ip.org/zip/SpaceshipsV2-2007.zip (4.8MB)
http://gurpsland.no-ip.org/zip/SpaceshipsV2-2007.7z (4.7MB)

OpenOffice 3.2.0/3.3.0/LiberOffice 4 RC9
http://gurpsland.no-ip.org/zip/SpaceshipsV2-Ooo.zip (3.4MB)
http://gurpsland.no-ip.org/zip/SpaceshipsV2-Ooo.7z (3.0MB)

[kmunoz]

Two things:

1) This is amazing.

2) Where did you learn to do this? After looking at your sheet I realized that if I could do something similar for my random monster generator I'd be able to make it cross-platform.

(There was a third thing that I got rid of because I'd misread your last post.)

[ericbsmith]

Originally Posted by kmunoz

Two things:

1) This is amazing.

2) Where did you learn to do this? After looking at your sheet I realized that if I could do something similar for my random monster generator I'd be able to make it cross-platform.

(There was a third thing that I got rid of because I'd misread your last post.)

1) Thank you.
2) Mostly, I've learned through trial and error. I learned some computer programming by going to college, and that's helped immensely in the Macros, but most of the functions of the spreadsheet itself I just googled it when there was something I wanted to do and didn't know how. A lot of the things I do that look complex are really just combinations of three or four simple tricks combined to make something more complex happen (such as the drop-down menus which can change their offerings based on other criteria you select). And, really, mostly it's just familiarity. I've been developing this spreadsheet for 7 or 8 years already, maybe longer (the oldest backup file I have is from 2011, but that was already v1.36 of the sheet). I've been messing with spreadsheets for 20 years, going back to the version of Microsoft Works I got with my first computer in 1996.
3) I saw your third point, and compatibility is something I've had in mind. In fact, largely it's why I've been rewriting the Macros for the last year or more. Last time I tried running the RC9 version of the sheet in LibreOffice it took something like 6 minutes to execute a Load/Save ship command. Last time I tested the new macros it was more like 20 seconds to (mostly) load a ship. Of course, I also pitched a ton of errors, which is one of the reasons why the rewriting has been very slow. And while that 20 seconds is kind of slow compared to the ~1.5 seconds it takes in Excel, it is at least usable speedwise.

[kmunoz]

I'm the same way with FileMaker Pro. I've been using it for 20+ years, ever since I built a database for a Psych department. Sadly it's not the most cross-platform-friendly program and most people don't use Macs. :(

Maybe I can trial and error my way through... A randomizer certainly won't be nearly as complex as Spaceships.

[davester65]

Great! Thanks for the update as well as a great generator which is fun to use. Hopefully the issues with Open Office can be worked out.

[adm]

Originally Posted by ericbsmith

1) ... I've been developing this spreadsheet for 7 or 8 years already, maybe longer (the oldest backup file I have is from 2011, but that was already v1.36 of the sheet). ...

The oldest one I have is from July 4 2009, I don't see a version number.