Stonehenge 3: A fast, precise robot arm

[rghansen]

I'm still surprised at how few people have tried to build Philo's stonehenge project which can be found at http://mindstorms.lego.com/en-us/suppor ... l%204.aspx.

Building it was not only a real learning experience, but also a lot of fun. It's also kept me very busy improving on it and learning even more about making better robots.

In addition to making the arm faster and more precise, I've also greatly improved my sorting algorithm. Although I've also improved my video
, I'm still a better engineer than a film maker.

[dudmaster]

Very nice!

[philoo]

Excellent, Ron!
Any chance you share your code and/or photos of your improvements? I see that you light shielded the colors sensor - which is a good idea, it's clearly one weak point of my design...

[rghansen]

Philo, thanks for the complement, coming from a man of your caliber, that's a real complement. But the easiest way to look good is to improve something that's already excellent.

I'll happily post the source code, but I'm too much of a newbee to know how to do it properly. At 1500 lines, it seems a bit long to just drop it into the middle of a forum.

Most of the hardware changes that I made where minor, and most of them probably weren't necessary. But I'll take some close up photos and post them on the weekend.

[rghansen]

Very nice!

You're only 11!?!? You're going to be awesome before you become old enough to drink. (And then it goes down hill from there).

In any case, thanks for the complement.

[mightor]

I'll happily post the source code, but I'm too much of a newbee to know how to do it properly. At 1500 lines, it seems a bit long to just drop it into the middle of a forum.

Just attach the source code file to a post. As long as it's less than 5MB, you should be fine

- Xander

[rghansen]

I'll happily post the source code, but I'm too much of a newbee to know how to do it properly. At 1500 lines, it seems a bit long to just drop it into the middle of a forum.

Just attach the source code file to a post. As long as it's less than 5MB, you should be fine

- Xander

I tried to attach the source file, but was told that "The extension nxc is not allowed". Maybe I should stick with programming robots.

[mightor]

Throw it in a zip file and you'll be fine

- Xander

[rghansen]

Thanks for the tip.

And now for the usual disclaimer:

This code is not as clean as I'd like it to be.

It's not as well documented as it should be.

But anyone is free to use any or all of it.

I'm willing to answer any questions anyone may have.

Hansen's first law of software applies (There are only two kinds of software: improvable or beyond redemption)

[rbnnxt]

I've built up the stonehenge model and modified it as best I can from your video (any chance of the photos showing changes?) In particular I've altered the grabber motor drive, the ball chute at the bottom end and the screening round the colour sensor. I've downloaded and compiled the program, and it runs with the following sequence.
The grab closes
The arm raises
The arm rotates to the zero position
the arm rotates until over the bottom of the chute
the arm lowers and stop clear of the chute
the grab opens
the arm raises
the arm lowers a tiny bit
then the program stops

I seen there is a simulation mode, but this needs the file nxc.h to compile which is not present.
Any ideas as to where I go from here?