how do i make a walking gun firing robot??

i've made a model based on a maddcat from the mech warrior series but i don't know how to do the script i would like it to walk, fire its guns ones and auto cannon ones a laser and i would like it to use its jet pack. if you can help or want to have a go im me and i'll give you one of the maddcats

First of all it would be a huge, huge, huge amount of work.

Problems:
* You would be moving prims about in the model which would likely not sync up properly or be fluid.
* If you are using physics which it sounds like you would want to, moving prims would likely cause you to loose physics (when you interpolate with other objects). Physics also requires you keep the prim count down, 30 or 31 prims in this case.

can't he make it an avatar?

I always liked the look of the MadCat/Timber Wolf, the best of the catapult and maruder designs meshed and made modular (what!? I worked in a gaming store ages back)

you could try to make it independant, but as strife noted, movement is gonna be REALLY tough, even with multi move.

best options are an Av that you wear, which has the benefit of using mouslook for guns, but being small (I actually think someone makes mech av's, try aetherstyle and mechmind for starters) or...

make it as a vehicle, that is heavy on attachments... most of the vehicle will actually be avatar attachments, so the 31 prim limit won't hurt at all. on the plus side it can be a lot bigger, on the down-side, the leg movements may be hard to do, but not impossible

either option is going to take some custom animations to look it's best

............a bot?

evil.... funny, but evil.... though traditionally mecha have pilots... all that not trusting AI and such

not that mobile automated defense turrets aren't unheard of of....

No, I was serious. The OP was unclear what he was actually trying to do (also, define 'model'...it's an important point. Where did you make this model, and what form is it in?): make an avatar to sell, or make an autonomous unit that walked around and shot (presumably harmless?) guns.

So why not a bot? It would wear the model like an avatar, and be programmable in a much more flexible and powerful way than straight LSL. Be a heck of a project, though.

Bots: They're not just for content theft.

I'm not against the idea, there just a lot of history in this game...

as for the model, this page provides game color background and some pics
http://www.sarna.net/wiki/Mad_Cat

You are actually looking at several projects here, and like the others have said, there are a few ways you could handle this:

Make it as a Vehicle:
You will be needing at least four sets of scripts here: the physical movement script, leg movement, weapons script, Jumpjet and weapons particles. If you were a wizard with sculpties, I would think you could probably do a reasonably detailed version in 31 prims or less. Otherwise, you can use the trick used by many ship builders, which is to build a 31 prim simplified version of the vehicle which rezzes all the detailed parts. When you sit in the vehicle, the detailed part attaches to you as a regular attachment, and when you stand up, it de-rezzes.

Articulated movement of limbs could be done with alpha animations, as many ridable animals if SL are. Basically, for Right and left, you make about 5 legs, each with a script to turn them Alpha or Opaque: This requires a central script to tell the legs "frame 1: left leg1 and right leg 1 opaque, Frame 2: Left leg 2 and Right leg 5 opaque" and so on. The legs then go from Alpha to opaque as told, creating the illusion of movement. This has a number of downsides, and in laggy environments, doesn't look terrific.

Weapons: outside of the usual LL gun scripts, there are a plethora of combat systems that you can pretty much drop into the appropriate prims and go. V.I.C.E and DCS are two I see a lot of, but you should consider where you would be using these weapons. if they are strictly for show, then perhaps it would be better to design a particle emitter to give the look of weapons fire.

Make it as an Avatar:
This would decrease the number of scripts you will need. As this is the scripting forum and not the animation forum (and I am very bad at animations ), I will say that you will need and Animation Override script. There is a freebie one out there for making 5 meter tall mech avatars which I believe is simply called "Mech AO." Otherwise, you can take a standard empty AO, such as the ZHAO or Franimation AO scripts (there are examples in here in the forums), and create the animations you need (remembering to upload them at a priority 4). This is the hardest part. After than, you get back to the drag-and-drop combat systems, and-or particle effects.

Big projects like this simply must be broken down into little projects, otherwise they can be very overwhelming. I highly recommend looking at how various content creators have built similar things, maybe even spend a few linden for something you can take apart to see how it ticks.

Sculpties aren't suitable for this. Look at all those hard edges! You can do a vehicle, just have to plan carefully that the parts that need to be physics-enabled are in the 30-prim base, and the rest are attachments.