Computer needs in MT craft design

[McPerth]

Since I read first time MT and began to design some ships, I assumed the maximum CP imput for each computer is a flat number beyond what the computer is unable to control the ship, so needing add ons, non linked controls or higher rated computer if you exceded it, while the multiplier was applied to the linked controls to see how many CPs needs they fulfill.

Now, on another thread, Aramis posted:

Ships in MT are Required to have 3 computers.

(...)

Note that a model 0 can support up to 2500CP... (500 max in, x5 multiple)which means Hull, Drives, Weapons, Electronics and Environment totaling not more than MCr(250/TL)
Model 1: 5000Cpimax, x10, 50,000CP, for MCr(5000/TL), min TL6,
Model 2:10KCpimax, x15, 150,000CP, MCr(15000/TL), min TL 7
Model 3: 15KCpimax, x20, 300,000CP, MCr(30,000/TL), min TL9
Etc.

Note that you can boost this a little with Add-ons - they come AFTER the computer, and don't get multiplied by it.

I know his knowledge of Traveller (most editions) is usually higher than mine, but I cannot find a clear description of the maximum CP imput in the rules, so, the multiplier is applied also to it?

 

[aramis]

Well, the effects on linked control panels is mentioned on page 60.

Computer and Control Panels: A computer is required to aid the operator or operators in controlling the craft’s functions. A computer multiplies the effects of the ship’s installed control panels if the control panels are of the “linked” type.
(MT RM, page 60)​

And, from the consolidated errata section on the RM.:

Page 81, Step 3, Computers (clarification and correction): Computer prices are in MCr. 9/bis computer should be 9/fib. Max CP input for a 9/fib computer should be 100 million.
The input CP is the maximum control panel input the computer can handle. You cannot connect more control panel CPs to the input side of the computer than listed here. If the control panel output times the computer multiplier does not totally satisfy the control panel needs of the craft in question, the craft will not work correctly.​

 

[atpollard]

I am surely no expert, but this:

The Regal needs nearly 6 million control points in control panels and computer equipment. The best computer we can install is a TL14 model-8/fib, which multiplies the CP input from our control panels by 95. To see how much CP input into the computer we need in order to get 5,732,187.75 control points out, we can divide that by the computer‘s multiplier of 95, giving us 60,339 CP needed as input.
We look at steps 4 and 5 on page 81 to determine our control panel mix. For starters, we know we have a big crew. A good way to provide the crew with good control input is to install several large holodisplays—in this case we‘ll say 10 of them. That‘s 15,000 CP right of the top, leaving 45,339 CP. We can cover the remaining CP with holographic linked (also sometimes called holodynamic linked) control panel units. Each of these provides 1.5 CP, so again, dividing we get: 45,339/1.5, or 30,226 control panel units. Because a starship is a ―flying craft‖, we need to install three computers (2 backups). We also opt for electronic circuit protection, which multiplies the weight and price of all these components by 1.5.

from

A MegaTraveller Starship Design Example
--by Joe D. Fugate Sr. (from Travellers‘ Digest #13 and #21)
The original article from Traveller‘s Digest has been recognized by the MegaTraveller community for a long time as being the best-written work on designing starships—except for some small bits of errata which make the numbers fail completely. In addition, in the Traveller Q&A article in TD #21, Joe Fugate provided possible answers to this article‘s shortcomings. Joe also gave some additional insights provided on staterooms and accommodations in the Traveller Q&A article in TD #19. It is my intention, with Joe Fugate‘s permission, to piece these together, fix the numbers and make Mr. Fugate‘s example finally work. Where I have changed numbers and text from the originals, or added my own material, is marked by red text below.
--Don McKinney (don.mckinney@gmail.com)
Version 2.02, 3/05/08

seems to treat the add-ons as modifiers to the input side of the computer and subject to the computer CP multiplier.

[unless I misread it ... not an impossibility]
Arthur

 

[atpollard]

... and if I do understand the MegaTraveller CP rules correctly, panel add-ons totally rock!

 

[McPerth]

I am surely no expert, but this:

The Regal needs nearly 6 million control points in control panels and computer equipment. The best computer we can install is a TL14 model-8/fib, which multiplies the CP input from our control panels by 95. To see how much CP input into the computer we need in order to get 5,732,187.75 control points out, we can divide that by the computer‘s multiplier of 95, giving us 60,339 CP needed as input.
We look at steps 4 and 5 on page 81 to determine our control panel mix. For starters, we know we have a big crew. A good way to provide the crew with good control input is to install several large holodisplays—in this case we‘ll say 10 of them. That‘s 15,000 CP right of the top, leaving 45,339 CP. We can cover the remaining CP with holographic linked (also sometimes called holodynamic linked) control panel units. Each of these provides 1.5 CP, so again, dividing we get: 45,339/1.5, or 30,226 control panel units. Because a starship is a ―flying craft‖, we need to install three computers (2 backups). We also opt for electronic circuit protection, which multiplies the weight and price of all these components by 1.5.

seems to treat the add-ons as modifiers to the input side of the computer and subject to the computer CP multiplier.

Well, the effects on linked control panels is mentioned on page 60.

Computer and Control Panels: A computer is required to aid the operator or operators in controlling the craft’s functions. A computer multiplies the effects of the ship’s installed control panels if the control panels are of the “linked” type.(MT RM, page 60)​

(emphasis is mine)

So, As I read Aramis quote, add ons should not be multiplied, as they are not linked panels.

As I read the rules, the Regal needs 5,732,188 CPs (as this is the minimum, I round them up), from which 15000 are from the large holodisplays and the rest (5717188) need to be fulfilled by panels. As each holodinamic panel fulfills 142.5 (95 x 1.5) CPs, 40121 are needed.

And, as the needs for the ship are lower than the computer maximum imput (50 million for a computer 8/fib), there are no problems on this.

And, from the consolidated errata section on the RM.:

Page 81, Step 3, Computers (clarification and correction): Computer prices are in MCr. 9/bis computer should be 9/fib. Max CP input for a 9/fib computer should be 100 million.
The input CP is the maximum control panel input the computer can handle. You cannot connect more control panel CPs to the input side of the computer than listed here. If the control panel output times the computer multiplier does not totally satisfy the control panel needs of the craft in question, the craft will not work correctly.​

As I read it, this does not mean the maximum imput is multiplied by the multiplier, but only the pannels. If you have a computer 9, each holodinamic panel will imput 180 (120 x 1.5) CPs to the computer, but its maximum will be 100 million CPs.

See that if you multiply it, a TL9 ship, with a computer 3 (maximum for the TL, and BTW, in my RM copy numbers are 20 KCP and multiplier 25, so it would be 500000 CP, so 50000/TL MCr) could be as much as MCr 5555.55..., allowilg for quite big ships to be built, and at TL 10 (computer 4, 50 KCP, multiplier 30, so 1500000 CPs, 150000/TL MCr), the maximum imput would be MCr 15000... All those numbers are quite higher than expected to keep at large the maximum size to the 19999 dton at TL9 and 49999 dton at TL10 shown in HG...

 

[aramis]

You don't run non-linked panels into the computer.

 

[McPerth]

You don't run non-linked panels into the computer.

That's what I understand, so add ons are computed aside from the CP run by the computer, do I understand right?

 

[atpollard]

Unless the add-on is added onto the panel (like a holodisplay) in which case the add-on adds its CP to the Linked Control Panel's CP and this combined CP is then multiplied by the computer.

Remember, I am a CT guy, so I have no dog in this fight. I view MegaTraveller as a great source of deckplan chrome. It is ultimately the author, Joe Fugate, who wrote the above quote and disagrees with your perfectly reasonable conclusions.

Note that Step 5 on page 81 of the Referee's Manual lists "Special Control Panel Add-Ons" not "Special Computer Add-Ons".

 

[atpollard]

So as I read the rules:

Ivan the Idiot decides to add a TL 9 Heads-up Display (+50 CP) to his single TL 7 Electronic Control Panel (0.5 CP) for a combined 50.5 CP control panel. Since the control panel is not ‘linked’ it cannot be connected to a computer and cannot be multiplied by the computer.

Fred the Bright decides to add a TL 13 Heads-up HoloDisplay (+200 CP) to his single TL 13 Holographic Linked Control Panel (1.5 CP) for a combined 201.5 CP control panel. Since the control panel is ‘linked’ it can be connected to a computer and can be multiplied by the computer, so Fred wires it to a Model 1 Computer (x10 CP) allowing the 201.5 CP Control Panel to exert 2015 CP on the ship.

This understanding of the rules agrees with the example by Joe Fugate.
Like so much of MegaTraveller, only God knows for sure what the designers had in mind.

 

[E.D.Quibell]

No Specials are just a different type of control pannel. They shouldn't have been listed as specials. They should just be listed as CPs.

So at TL 10 (makes it easy) if the total cost is Mcr 1, then the number of CPs needed is:

(1,000,000/100,000)*10 or 100 CP

The add the computer and adjust with the computer modifier:

Computer 2bis has a multiplier of 20. Meaning the number of CPs you now need is 100/20 or 5.

and then we add CPs in this case a special (as all specials need a computer they gain the use of the CP multiplier). So a head up display with a CP of 50, will cover all the CP requirements of the craft. No other CPs are thus needed.

And as your CP input to the computer is 50 this is well within the 15,000 maximum of the 2 bis.

Remember you don't need a computer to add CPs you just need to cover the amount needed. You could if you wanted use Basic Mecanical CPs to run a TL15 craft with no computer (I wouldn't recoment it, but it is posible).

Or in other words a Comp 0 can run 10 HUDs which in turn provides 2500 worth of CPs to the craft. With a Comp 0 the maximum cost of the craft (if you wish to only add computer linked CPs) would be Mcr 25.

Best regards,

Ewan

 

[aramis]

Unless the add-on is added onto the panel (like a holodisplay) in which case the add-on adds its CP to the Linked Control Panel's CP and this combined CP is then multiplied by the computer.

Remember, I am a CT guy, so I have no dog in this fight. I view MegaTraveller as a great source of deckplan chrome. It is ultimately the author, Joe Fugate, who wrote the above quote and disagrees with your perfectly reasonable conclusions.

Note that Step 5 on page 81 of the Referee's Manual lists "Special Control Panel Add-Ons" not "Special Computer Add-Ons".

Canon designs I've checked have no need for the add-ons to link through.

I'll note that a couple canonical designs abuse the add-ons rules a bit. Donosev (cough cough). And one exceeds the computer's CPMaxInput, but the extras provide the needed amount over unmultiplied. I forget which. I checked it back in 1992 or so...

 

[atpollard]

So true to form, MegaTraveller offers two official, contradictory and mutually exclusive instructions on yet another important rules detail. Sigh.

... that's why I like the Traveller Book (CT).

IMTU (and to the extent that I care) I prefer to stick with running the add-ons through the computer multiplier and choose Joe Fugate's interpretation as the design intent.
As E.D.Quibell points out, it makes the math a lot easier.

 

[SanDragon]

Fugate's interpretation?

I have never heard of this. I have been designing tech level 10 ships of 100 to 1100 ton sizes and pulling what little hair I have left tweaking them to fit into the given contradictory limits of control points.

Please enlighten me. Pretty please?

 

[aramis]

Fugate's interpretation?

I have never heard of this. I have been designing tech level 10 ships of 100 to 1100 ton sizes and pulling what little hair I have left tweaking them to fit into the given contradictory limits of control points.

Please enlighten me. Pretty please?

Joe Fugate wrote the example article. Which, BTW, made clear that DGP considered several questionable practices as permissible. Like multiple PP - one low-output for maneuver with 4+ weeks of maneuver, sensors and LS, and a second to power weapons, more sensors, and screens, but with only a few hours of fuel.

 

[McPerth]

Canon designs I've checked have no need for the add-ons to link through.

I'll note that a couple canonical designs abuse the add-ons rules a bit. Donosev (cough cough). And one exceeds the computer's CPMaxInput, but the extras provide the needed amount over unmultiplied. I forget which. I checked it back in 1992 or so...

And that is how I understand the add ons, as CPs counted aside from those in the computer (so allowing you a few CPs more than the computer maximum imput), and so not benefiting from the computer multiple (while still needing it, as rules clearly specify).

See that if they benefit from the computer multiple, a large holodisplay (1500 CP) is the equivalent to 1000 holodinamic panels, while using less volume (2 kl vs 30), power (0.05 Mw vs 2), weight (1 ton vs 20) and cost (0.5 MCr vs 1), while used without the computer multiple, holodinamic link panels are more efficient if computer is 3+ (all their needs above reduced by computer multiple).

In any case, as a house rule, I always limited those add ons to a maximum of 20% of the CPs needs of a craft, as they are purely information displaying devices, not true controls.

 

[atpollard]

Fugate's interpretation?
Please enlighten me. Pretty please?

Aramis explained 'what' and here is a 'where'.
Check out this site link:
Don McKinney Traveller Page

and this specific item:
MegaTravellerStarshipDesignExample

Happy shipbuilding.
Arthur

 

[McPerth]

NOTE: I quote here two posts in full (as well as responding) as IMO they are quite pertinent in this thread and for anyone that follows this thred not to lose them.

As someone else so eloquently put it, they're OUTPUT devices, and already require a computer. They certainly shouldn't count against the CP maximum input limit.

Also they need a limit of their own

If they do get the input bonus, then a scout ship can be run with a holo hud and a couple panels... also an issue.

I’m not sure what do you mean about input bonus here. If you mean a bonus to maximum input, that will not lower the computer needs for the scout ship, as to be able to jump 2 it needs at least a 1(bis) computer.

As someone else so eloquently put it, they're OUTPUT devices, and already require a computer. They certainly shouldn't count against the CP maximum input limit.

Also they need a limit of their own.

I think that when the errata already states that control panel add-ons "can act as a direct replacement for weaker control panel units" that pretty much means that an add-on IS a control panel ... so the only question remaining is are they 'linked'.

If they are linked, then they can plug into a computer, can gain the computer multiplier and do count towards the computer's maximum input.

If they are not linked, then they can't plug into a computer, can't gain the computer multiplier and don't count towards the computer's maximum input.

If they do get the input bonus, then a scout ship can be run with a holo hud and a couple panels... also an issue.

Why is this 'an issue'?
If it has the required CP then it meets the rules doesn't it?
[I'm not arguing or baiting, this is just a straight up question.]

That’s why I house ruled a maximum of 20% of CPs fulfilled by add-ons. Anyway, in the specific case of the Scout ship, I’d find logical to have some add-on support, as it is designed to have all controlled by a single crewmember.

 

[atpollard]

I’m not sure what do you mean about input bonus here.

I think that Aramis is referring to an add-on gaining the computer multiplier as "input bonus" and is pointing out that a simple add-on (like a HUD) plus a computer multiplier will allow one man to 'control' a ship with VERY FEW (like almost none) control panels.

Aramis takes issue with this but, personally, I imagine a HUD and 1 control panel unit like a modern cockpit with the HUD for data display and buttons on joysticks as one control panel unit for input ... both routed through a computer to multiply their effective ability to control a craft ... classic fly-by-wire technology.

... But I am an Architect, so what the heck do I know about the details of aircraft control computers.

 

[atpollard]

That’s why I house ruled a maximum of 20% of CPs fulfilled by add-ons. Anyway, in the specific case of the Scout ship, I’d find logical to have some add-on support, as it is designed to have all controlled by a single crewmember.

Your 20% sounds like a good rule for large ships with lots of crew to avoid a cruiser with each crew member from the captain to the cook having a personal large Holodisplay or Holographic HUD to maximize control points beyond how far the suspenders of disbelief will stretch.

The official errata of no more than 1 add-on per crew member works well for a free-trader type of small starship where all hands can man a station in a crisis ... even if that station is a Holographic HUD with matching control panels.

 

[McPerth]

I think that Aramis is referring to an add-on gaining the computer multiplier as "input bonus" and is pointing out that a simple add-on (like a HUD) plus a computer multiplier will allow one man to 'control' a ship with VERY FEW (like almost none) control panels.

Aramis takes issue with this but, personally, I imagine a HUD and 1 control panel unit like a modern cockpit with the HUD for data display and buttons on joysticks as one control panel unit for input ... both routed through a computer to multiply their effective ability to control a craft ... classic fly-by-wire technology.

... But I am an Architect, so what the heck do I know about the details of aircraft control computers.

Neither I am an expert (to say the least) in this field, but even in a civilian car (quite few CPs), and even with the increasing computer support they have now, there several controls (direction weel, acceleration and brake pedals, gear switch, glass cleaners, lights, etc).

Even if some (e.g. gear switch) may be automated, the driver is continuously using at least 2-3 of them, aside from the displays he may have before his/her eyes.

I don't know about an aircraft, but I guess there are alot more of them, and I envision a starship having even quite more controls, aside form any information display (add-ons) it has. I keep thinking that add-ons, as information displays, may only fulfill a small amount of the CPs (I took the 20% out of my hat, but sure there's a limit), as this is only output from the computer, while other controls are needed for the true imputs.