This will probably be my first house rule when I start running an SR4 game. I've included part of the flavor text and the first draft of the actual rules I intend to handout to my players. I'm looking to know what you think, is it ballanced, is it necessary, are there problems the way it's writen?


OneTrikPony’s Cyberlimb house Rule.

Flavor text:

How do cyberlimbs work
Modern implant prosthesis are modeled after biological systems so that they generally mimic the part that is being replaced as closely as possible. Standard replacements are usually synthetic and constructed in such a way to provide seamless operation with natural balance, feel and sensation. To the user natural operation and sensation are as important as superficial look and feel. This is accomplished in several ways. First the components used in construction of the replacement match not only the dimensions of the natural limb but also closely replicate the limb’s weight and density for balance. Neural mapping of the recipient allows connection of the motor systems to neural pathways that closely correspond to those used by the part being replaced. Environmental and mechanical stress sensory systems are matched to the recipient. Finally fine calibration of the motor controls, actuators and sensory systems give the implanted prosthesis a natural feel and operation that is close to indistinguishable from the natural part.

Implant Prosthesis Systems:

Frame…the frame of the replacement, analogous to a biological skeleton is usually machined from high tensile polymers. These materials have a density similar to bone and often surpass biological bone in strength. Stress areas and wear surfaces are often reinforced to provide longer service and superior performance.

Actuators… The “muscles” of implant prostheses are usualy composed of myometric polymers, (tendons and ligaments), and micro scale piezoelectric servo bundles, (muscle fibers), that are light, durable power efficient and low maintenance. These materials allow near infinite force sensitivity while also providing an excellent source of stress and positioning feedback to the sensory systems.

Power systems… These days almost all implant prostheses are powered by low voltage electrical current generated from bioelectricity collector arrays implanted along major neural pathways local to the operation. (In rare or extreme cases heat sinks and chemical converters might be used as well.) The arrays are routed to the power module contained within the prosthesis which both stores and dispenses the energy as needed.

Control Systems… Prosthetic control systems are composed of a computor, (the Control Module and Operating system), Motor Control Units, and a Neural Transducer. The Neural Transducer translates signals between the biological nervous system and the Control module. The Control Module takes motor control commands as well as operator instructions and coordinates movement and other actions in the prosthesis issuing commands to the Motor Control Units and other devices within the limb. The Control Module also gathers and interprets sensory and feedback information for transmission up stream to the central nervous system. Motor Control Units drive the actuators via power distributed by the Power Module.

Sensory Systems… Somatosensory data is collected by two systems; the Environmental Sensory system and the Stress/Feedback Sensory systems allow the prosthesis to provide sensation to the user. The Environmental Sensory system collects the sensory data of temperature, pressure, touch and vibration. The conditions are measured by thousands of micro sensors imbedded in the Integument Structure, (skin or analog thereof), The signal is collected and formatted by the Control Module then translated to nerve impulses for sensation by the Neural Transducer. The Stress/Feedback Sensory system is comprised of internal as well as external sensors that allow the Control Module to signal sensations of muscle activity, joint position including posture, kinesthesia (movement), as well as analogs of pain and tissue damage.

Integument systems… These days you have a choice of synthetic skins that can be matched perfectly to natural skin tones and textures even down to follicle and pore count. These synthetics are nearly indistinguishable from natural skin to the eye, and they feel almost like the real thing. Besides carrying most of the sensors of the Environmental Sensory systems, the integument system protects more vulnerable inner workings of the prosthesis, providing a measure of cushioning to more sensitive electronics, protecting the Actuators from abrasion and keeping the elements away from joints. Most important is the Integumentary Cuff. The interface between the flesh and the machine is a weak point, a permanent wound, where natural skin is forever open. The Integumentary Cuff, an open cell foam compound impregnated with dermatropic hormones, permanently seals the junction between the natural skin and the prosthetic socket keeping the flesh protected from the entrance of toxins and bacteria and substances.

Obvious cyberlimbs are less common than Sinthetics and generally only installed at the direction of the patient. Obvious implant prostheses include all of the systems of a synthetic limb in one form or another but often include additional systems and upgrades as required by the recipient, usually for utility or military purposes. The upgrade or addition of ancillary systems is more easily accomplished in an obvious limb because technicians are less concerned with natural balance, feel and appearance. Thus there is more leeway in design specification of an obvious limb. The obvious cyberlimb is, to a point, capable of containing larger or a greater number of apparatus, vocation related electronics, tools, armor or weapons.

RULES;

Concealability…

I would increase the capacity for larger limbs - they have more space.
I would get rid of the size modification for capacity but charge differently for each.
Humans, Dwarves, and Elves get medium limbs, Orks get large, and Trolls get extra large (somebody elses fix but I use it too now). Larger limbs cost more.
I would allow out of size limbs to be used with no problem (there is a picture in the book of a troll with human arms attached to his hips with a gun held under the table.). You could have a gorilla man as well.
Other then that it looks pretty good.

Troll limbs need to have more capacity - if you scale anything up, free space gets scaled up too. They would comparativly offer more relative space than their smaller counterparts, due to relativly smaller controls and structure.

Higher attributes should not cost capacity. The limiting factor is the human flesh, not the cyberlimb size. Cyberlimb weight is a mayor consideration, but not handled by the rules so far. Pairs of cyberlimbs get rid of this problem.

Cost-wise, any race would pay the same. Size doesn´t cost much, attributes would need to be payed. Larger servo = higher cost. Trolls pay - and get - much more.

Doesnt look to bad sofar.

I dont think you need to change the weight / density of the limb, as you can adjust the muscles / motors to make it feel the same to the natural limb.

Id stick to same price / capacity for all limbs, a troll limb may be bigger, but its layout is bigger as well and the parts to be included will be slightly bigger as well.
You dont pay more essence for troll spurs compared to dwarf spurs.
Keep it simple in that deparment.

Slightly off topic: I never understood why grown limbs were cheaper then cyberlimbs. Massproduction of cyberlimbs should be possible with little customization in the last step and you can stock em.
You cant do that with grown limbs.

I kind of think that higher atributes should cost capacity. the ratio of strength to volume isn't linear AFAIK. the arm isn't only bigger but proportionaly stronger (i think) so it seems to me that an arm of twice the linear length needs something like 3 times the muscular cross section.

of course the arm could just draw more power per servo unit but the bioelectric system stuff they started is allready stretching my suspension of disbelief.

The metavarient limbs cost more for a variety of reasons but primarily because they're not off the rack (and also I just wan't cyberlimbs to be concidered as a viable choice they don't need to be the go-to item.)

These are my ideas for house rules:


CYBERLIMBS

Increased Resilience
Each Cyberlimb and the Cybertorso adds +1 to the characters Physical Condition Monitor.

Every two Cyberlimbs adds +1 to the characters Overdamage monitor – The Cybertorso adds +1 to the characters Overdamage Monitor.

Increased Armor
Every two Cyberlimbs adds 1/1 to the characters armor and the Cybertorso adds 1/1. Maximum bonus from cyberlimbs and shells cannot be more than B3/I3.

Attribute Limit
Physical attributes on a limb mimics those of the owner thanks to a hardwired sensor system that monitors muscle responses from the characters nerve-bundles. It’s impossible to remove these attribute limitations unless you have a good skill in Cybertechnology, Hardware and Cracking as there are both hardware locks and software security to ensure that people will not hurt themselves. The system is not wireless and cannot be accessed without taking the limb apart.

Cyberlimb Availability Changes
All Cyberlimbs, Torsos and Skulls have an Availability of 4 for Obvious versions and 8 for Synthetic versions.

Cyberlimb Prices
All cyber replacement parts follow the prices of Synthetic replacements – Synthetic replacements simply gains concealability to the obvious limbs extra space.

Essence Changes
Cyberlimb: 1,00
Cybertorso: 1,00
Cyberskull: 0,50

What Can Be Installed?
Cyberlimbs & Shells have the versatility of being able to install nearly every piece of cyberware available with a bit of tweaking. The following types of gear can be installed in a cybernetic replacement or shells. If it is not in then list it does no longer exist.

Headware & Bodyware: Any kind of bodyware with a Capacity Rating [?]
Bodyware: Control Rig as Implanted Commlink.
Eyeware & Earware Cybereye and Ear takes up 1 Capacity each.*
Cyber Holster: Can only be installed in a Cyberleg
Cyberarm Slide: Can only contain Hold-out and Light pistols

*In order to install Eye and Ear modifications you still need to install a cybernetic replacement.

Why is a dwarf cyberarm stronger than a human cyberarm?
Why does an elf cyberarm have more agility than a human cyberarm?

I have a section about cyberlimbs in my SHP (signature, last 2 pages). This is where I introduced this "medium, large, and extra large" stuff. I tried to change as litle as possible there.

Because they are built to match the body.

These are my cyberlimb house rules:

So what is the reason then why the smaller dwarf cyberarms have a higher strenth maximum? And the elf cyberarms that are alsmost indistinguishable from human cyberarms have more max agility?

Maximum is what is possible technologically, not what "fits the body". A cyberarm with "dwarf and elf" technology in it would also fit a human.

As I said, they are built to match the body (or the metatype).

A standard-dwarf cyberarm is set-up to work just like an average dwarven arm would.
And so on.

If one wanted to make it more realistic (as opposed to more playable), each metatype would have to have different rules for cyberlimbs, different capacities, etc. An elf cannot use a human cyberlimb, their bodies are already too different. Also, the actual physical attributes of the patient would have to come into play, as well as height, body frame, and so on. But that's too much hassle for too little impact.

Bye
Thanee

P.S. Why do XL limbs get less Agility than the others in your rules, Serbitar? Isn't that exactly the opposite of what you are saying with dwarves, elves and humans using the same technology? Why do trolls get weaker tech there?

My point is:
If you could make a cyberarm for a dwarf with strength 10, you could make one for a human with 10 or even 11, as it is bigger.

The shape/size/weight of an elfs arm also does not justiy an additional agility point, as it is essentally the same as a humans.

Thus: Elfs, dwarf and humans cyberlimbs should have exactly the same stats.

Trolls arms have less agility, because they are too big. Thats a physical limitation. A big arm just can not, with the same technology, be as nimble as a small one. And the difference in size and weight is quite considerable.

Stronger motors do not necessarily mean larger weigth and size. And muscle diameter has to increase with strength, yes. But on a biological limb, muscles determine volume. Thats not likely with myomeric muscles, as myomeric rope is now possible. Therefore their tensile strength has to be much higher. The more musculature has to be replaced, the more volume is gained for other applications.

Fit to the meat body in size. The rest is irrelevant. It can be strong as hell.
Point is, that a smaller dwarf cyberarm can never be stronger than a larger human cyberarm, suing the same technology.

The limiter has never been the strength of the machinery. Its the strength of the mount where the arm connects to the flesh.

If we were just bolting these arms to test benches, we could design one strong enough to pick up light trucks by the front bumper. Try that when it's mounted to a metahuman, and it'll rip from it's flesh and blood moorings before the front tires leave the ground.

In short, the limit is a fixed delta over the natural maximum strength of the particular metatype.

Even if this was the case (which I doubt, just draw it, it does not look natural at all), the arms would still be same size.

@Paul: OK, thats a reason for strength, but for the rest ?

If you only think of simple physical issues (simple, meaning that it excludes the higher complexity stuff like nerves), then Body would be slightly related to size (not much though, and could easily be the same, considering, that the differences are not that big) and Strength (think: higher density materials) and Agility would be completely unrelated to everything and should be the same for every cyberlimb, regardless of size, metatype, or whatever else there is.

But in order to work like a completely natural extension, there must be a little more to it than just that.

Bye
Thanee

The Joop;

You mentioned something about 'hacking the Attribute limitations' on your cyberlimbs (been up all night ... too lazy to find the right quote ). What are your rules on that? And what limits do the cyberlimbs have after the hacking is successful?

RunnerPaul

You're missing rules for partial limbs.

What are the concealability modifiers for partial limbs?
Do partial limbs recieve the same attributes?
If I armor a partial limb, how is it counted?
And finally, do partial limbs add damage boxes like full sized ones?

Also:

What about my question?

Lagomorph;

Fortune:
I can't find that post that mentioned hacking atribute limits. I'm not yet familiar enough with the wireless world to have any House Rules for hacking limbs but I would like to note some things I've found that people may/may not be aware of.

That wasn't really what I meant at all. But as it turns out, upon actually re-reading the thread, that it wasn't your rules that I was questioning anyway (see previous comment about being up all night ... still haven't slept yet ) ... it was The Jopp ...

To wit ...

Actually there is something that has been bothering me about cyberware. In the previous editions it seems that they are saying that cyberware was causing essence loss because it was an electrical connection with your CNS. That was why cyberlimbs requiring considerable connection with the CNS to direct it took a full point but it didn't matter the size because the same number of nerves were connected (ie a troll limb doesn't cost more then a human's limb).

Okay so why does cybertorso cost so much essence?

Isn't it mostly just a can with some articulation? It acts as a frame for the cyberlimbs but I could see an articulated frame as a sort of back brace that supports the arms and doesn't kill your back. So what is the CNS connections about?

I mean I can even see some of the cyberskull with the jaw but Ican't it all that much essence loss.

Suggestion: Incorporate the idea of the jopp and allow cyberlimbs to be fitted to the non-cyber attributes of the wearer. This is possible without changing the hardware up to natural limit-1. Overdrive is a simple cybernetics check. If you overdrive speed or strength without cybertorso, you take (used rating-natural rating) DV stun, resisted with natural body.

Ingame reason: The standarised cyberlimb would have to fit all customers except the exceptional. Athletes suffer injuries too. Mismatching is easy, but generally not wanted.

Outgame reason: Easy. No limit for most characters. If its a limit, the difference can now be payed without filling the cyberlimb up.

Maybe i just don't understand Joop's ideas but I think he's saying that you can pay for a strength 3 cyberarm then make a hacking extended test to get a strength 5 cyber arm. which means that you had a strength 5 cyberarm all along. They just had it turned down.

That's like asking Dell to sell you a desktop with an UNDERCLOCKED conroe processor because your only going to use it for word prosessing.

If I hack into the firmware of my 4 banger car's ECU and upload firmware from a V6 do you think I'll be able to drive faster?

Or to put it in shadowrun terms

Maybe the crapy responce of my Meta Link comm is realy just a software issue. If I hack my own comlink can I increase the responce and signal?

NO.

it's not software. It's hardware. a strength 4 limb has a strength of 4 because it only has rating 4 actuators. you can't make a 4 cylinder engine into a 6 cylinder engine without adding at least 2 cylinders. You can't make a strength 4 cyber arm into a strenght 6 cyberarm without adding some mechanical hardware.

Within conventional wisdom, you are correct.

An economically knowledgeable person might suggest that the cost of producing several hardware variants would be higher than producing one model per needed size class and customizing it by software. Several years ago NVIDIA was serving the low-cost marked with a so-called "damaged goods-policy". Low-end graphic cards (forgot the type) had all the same chips and makeup, only some chips were not fully connected. Customers not willing to pay full price didn´t get full performance. (Note this is not NVIDIAS term for said policy, nor is it out of order with common business strategies. It´s just rarely economically feasible to do so).

A rating 4 cyberlimb may be a rating 4 cyberlimb because more would tear the shoulder of the customer, resulting in a lost trial and bad publicity for the producing company. Hack at your own risk.

Remember that a synthetic limb is nearly undetectable to visual inspection. Were not talking about robot arms here.

based on what I know of prosthetics today. I can't immagine that cyberlimbs (other than used ware) exist as complete assemblies. Even for an unaugmented cyberlimb there are just too many variables that have to be matched for comfortable use.

do all cyber legs, lower legs, and cyber feet have the same shoe size? Would you immagine that the medical comunity would produce a unisex cyber arm and if so does it have man hands or woman hands? This is nothing like a GPU. Which is sweet, cuz I'll cry if next years dual SLI set up costs Twenty Thousand Dollars

I immagine that there are "Stock Parts" for cyberlimbs, not assembled "Stock Limbs". I mean it's entirely feasable that there are standarized molds for the equivelants of the radius and ulna in a cyber arm frame. They probably come in different sizes that vary in length and girth with a varience in steps several milimeters.

Basicly; a patient needs a replacement arm. The med/tech takes carefull measurements of the remaining limb and uses standardized parts of one or several manufacturers to assemble a limb that very closely matches the length, girth, weight, ballance, and sensory biometry of the natural limb.

I give up.

Of course, this would only be true if there was enough of a market for cyberlimbs for large economies of scale. Cyberlimbs would have to be both cheap and significantly better than original flesh to people to get voluntary replacements. And would have to be much cheaper and about as good as flesh for industrial accident replacements.

I think that you could do it either way depending on the feel of the game you are going for. It's not that you couldn't do it or that it wouldmake sense to size everything but it depends on if the campaign is gritty and uncaring on the side of the corps or if you are having them nicer.
If you are doing blackmarket then your going to get a arm that is close to right but may not really match your other arm. They could spray paint it to get the color closer but anyone shaking your hand would get a notice test in my opinion.
Now if you have a high lifestyle then you would get more details correct. I would say not charge any different but make it closer to normal depending on your source and your lifestyle level (consider it an incidental cost for high lifestyle and maybe not available at low).

OneTrickPony, you are right in that replacement of one limb requires much more finetuning than replacement of both. SR does away with that level of complexity and just has one price.

For motor controls and strength it will not be feasible to use more than one set of parts. The cost of stronger servos is not that high, and you are customising enough parts to fit length, shoe size etc. I imagine that most of your money goes to a myriad of sensors allowing you to feel the prostetic as part of your body. And it will be hard to cut corners there. If you wanted to model different qualities of cyberlimbs, you could introduce modifiers for tests involving fine motor control of the limb. Again, too much complexity for basic SR. My point is just that you don´t stand to gain much by using smaller motors. Neither space in the limb nor money for the company.

No, I mean that the price for one arm is half the price of two arms.

Two arms would be less expensive per limb because you´d not need to tune the replacement to the capabilities of the flesh counterpart.

Slightly off-topic : I wonder if we can't consolidate some of these cyberlimb threads.