CAD Drawings etc.

[stu]

Jono, you dont need cad mate.
Just get a load of bits, and bodge something together for your first time. You will learn alot by it. Then at a later date you can re design and improve on your current ideas etc.

Mr Stu

[stu]

Nice one.

Mr Stu

[fwsorg]

Totally agree with Stu- CAD for the sake of it is pointless and just causes stress. A 2D system, of which there are many for very little money (and some are free), is a boon for designing something, printing it out in 1:1 scale, sticking it on the material to be cut and cut it out. Then your robot will assemble like a piece of flat pack furniture, which is always nice :-) Dont bother with 3D stuff for the time being.

Yeah fair point.
I for one use AutoCad (proberly not all of its features) and the results look like its been done in paint but it gives me a to scale drawing where to put things. So i know if things fit and how big to make my chassis and all sorts.

It can be and has been done without using Cad, only reason i use Cad to do those things is to pass time while im collecting bits hehe.

Mr Stu

[fwsorg]

LOL!!! Id always been in denial about that, but its completely true :-)

At the risk of subverting another topic...

Since Im from a (software) graphical background rather than an engineering one, Ive never really played with anything which calls itself a CAD package - but on the other hand Im reasonably fluent in 3DS Max, Maya and SoftImage (not at home, btw; if I had the bank balance to own that lot Id have a robot by now).

Ive not tried designing a robot in any of those, but can I ask what features people use which could be considered CAD, rather than modelling, specific?

I guess its easier to rip out the components in a format suitable for driving machining hardware in a CAD package (Ive not seen that facility in the modelling packages, although it probably wouldnt be hard to pull out a trim curve if you restricted yourself to simple surface types). Ive also not seen weight calculation facilities, but again there may be a way to get a volume calculation. Ive spent all my time getting the surfaces looking right (I know exactly how to get a nice brushed metal effect, but that doesnt help much), so this isnt the kind of thing Ive ever tried to do.

Most of my proto-designs are half in my head, half on the back of an envelope, but Id be interested in knowing what people find useful. Id be inclined to model as a final stage before trying to build, if only as a rough attempt and to ensure that nothing obvious is going to go wrong (centre of gravity behind the rear wheels, ram fouls on the batteries, that kind of thing) which I wouldnt be able to tell by placing all the components on a suitable bit of gardboard/MDF. The lay it all out principle only really works if what youre building is flattish, and Id prefer not to restrict myself.

Just wondering what benefits can be got from extending my repertoire!

--
Fluppet

Youve already answered a large part of it- outputing to CAM software/NC machines, and creating patterns and technical drawings for yourself. If my memory surves me correctly 3DS MAX will work with IGES files, which 99% of CAD programs can read (tho it is not a prefered format, by any means) so you conceivably CNC yourself some of your creations on 3DS max.

Fundamentally, it biols down to what the software packages are design to do. CAD packages are designed to make parts, and integrate, as much as possible, with other realted CAM and NC software. The options are more Enginerring specific, and the layout is set out with that in mind. I can lend you pro/Desktop at the next social (whenever it may be) so you can have a play yourself. I think Rhino is much more like 3DS MAX- much more inclined towards free-fprm modelling, curves, wire frams, and the like. Youll find the more parametric aspect of Pro/Desktop (or Autodesk, for that matter) lends itself more to the kind of stuff involved in robot builing. If you would like me to bring the CD along, gimme a shout.

We need to start charging you web space on this forum Andrew

Mr Stu