My NXT Scanner/Photocopier/Plotter V1

I've now had the Lego NXT set for just over a week and having done all the basic models I decided it was time to attempt something of my own. I attempted a Scanner earlier in the week and realised the programming for one is actually fairly simple and works quite nicely. As it was such a simple program I've decided to up the game a bit by trying to build a scanner that will store the coordinates in it's memory and then use it later on in the program to produce a photo copy of the original image. There are a few robots out there that produce a photocopy by having a pen run in parallel with the light sensor so when the light sensor senses black then the pen goes down, and when it sees white it goes back up again. This isn't really a photocopier but nonetheless it still works well and produces an accurate image.

I have spent about 3 days building this preliminary version of the scanner/photocopier and I decided that one of the big things i want to stick by is that I will only use pieces in the NXT 2.0 set so anyone can make it. There is a printer in 'The Unofficial LEGO MINDSTORMS NXT 2.0 Inventors Guide' by David J Perdue and Laurens Valk which uses just parts found in the set however it does not have the colour sensor attachment, you can see a video pf this printer in action here:
 http://www.youtube.com/watch?v=tNp62EfaJ60.

My first attempt at this model was not that great really, it was just to see if I could produce a scanner with the NXT 2.0 parts. The problem I had with my model is that the paper doesn't feed straight every time and the bar across the top sags slightly under the weight of the motors. Also the general build quality of the frame is very poor and not very strong at all. Below you can see an image of my first attempt.

Sorry about the camera quality the future photos should be better.

I'm going to completely scrap this model I think and the next model will have the motors vertically in the pen module to keep the length of the module as short as possible. I will also completely reconstruct the frame to make it a lot stronger. 

So hopefully in a few days I will have a stronger scanner that I can then start to program.

S