Designing the new body for my robot...
June 6, 2011
The first robot that I have ever made currently has a cardboard body. As one can imagine, cardboard has its limits, both in durability and aestetics.. So the last few weeks I decided to look around for another material... I wanted something that is relatively easy to form and work with and not needing a whole set of new, special, tools... I came across plexiglass as an alternative and my choice was quickly made.
I have built stuff before and usually writing a few measurements on paper works fine to make simple things. A robot body is a whole different cup of tea. Any holes of the separate pieces of plexiglass should be perfectly aligned, as a few millimeters off could break the plastic when screwing in the screws too tight. So, as precise as possible is important!
Now, when I was young, and because of my fathers' engineering profession, I have been able to dabble in AutoCAD (version 3.XX, running in DOS on a 80286 with a '287 mathmetical co-processor, ahhh the old days....), giving me a head-start on the digital engineering way of thinking...
Though now, more than 20 years later I don't have any access to a machine running AutoCAD... So I had to look around for a decent piece of CAD software -- software without any "typical" way and a steep learning curve to go with it. (Learning is good, but when you want to progress, it only slows things down.)
Enter CADuntu, which has recently been renamed to LibreCAD, a multi-platform CAD software (Windows, Linux and Mac OSX). I've tried other alternatives before -- but in the time I was still figuring out how the interfaces worked I was already designing in LibreCAD. If you ever used things like the command line, or "relative" coordinates by prefixing them with "@", it's a very comfortable environment.
It does not do 3D design -- so it is not possible to "shade" (render) a model, which would've been a nice bonus.
For saving files it uses the DXF file format; so any design could be imported into an application that does do 3D and modified/finalised in there.
But for now, 2D works just fine to get all the holes on the bottom and sides aligned correctly: I am now able to plot the "hole plan" and overlay that on a piece of plexiglass and cut right through -- so that's awesome! (The plexiglass is still in transit, sadly..)
Occasionally, I run into something that works so much nicer in the AutoCAD I've grown to love, but for which I still need to figure out how it's done in LibreCAD. For instance, I do miss the "JOIN" command (I doubt one must need "blocks" for that use -- blocks can't be "hatch"-ed either).... but other than that it's the best free CAD program I have run into so far!
Curious... Are there more people here that use this software?