robmiles.com

My name in lights…

After the fun and games of Geek Night I’ve now put all the source files and the presentation up.

• You can find the presentation here.
• You can find all the sample code here.

There are also some more audience pictures on Flickr. Click on the picture above to find your way to my photostream and take a look. I’m off to find a tram, a train and a plane now…

Oscar, my tiny Micro Framework powered robot has become the other first robot to be controlled by a Windows Phone. Charlie Kindel was kind enough to take part in my demo and give the robot commands during the talk. Thanks for that.

I nearly didn’t make it work though, loading the wrong firmware into a device is never going to end well, but in the end all the components fitted together and a happy ending ensued. I’ll have more pictures, and the slide deck that explains how it all works, along with demo code, tomorrow.

This was the setup, you can see Oscar next to my laptop, the Micro Framework board I used as a web host is on the far left.  I also had my own router and WIFI access point so that I could get the phone onto my own private internet…

If you are having bother positioning the support posts to hold your Fez Mini robot together you might find the above picture useful.  The PDF gives lots of good detail about how to fit the motors to the battery tray, but lining up the unit with the right screw holes on the base is a bit tricky. I think mine is right, at least the wheels seem straight enough for me. The back of the robot is at the bottom of the above picture.

Oh, and you don’t have to fit the line detectors where I have (just outside each wheel). This is part of an experiment I’m doing to find out how well grey scale line following can be made to work.

This is a still from a very embarrassing video:

http://www.devdays.nl/Video.aspx?pid=75

I’m doing it again. Geek Night at Dev Days. This time I’m taking my little robot Jason and a bag full of sensors and bits and pieces. We are going to create some embedded devices on the fly and have some good old .NET Micro Framework fun and games. If you are coming to Dev Days 2010 at the end of March, then it would be great to see you. You can find out more here:

http://www.devdays.nl/GeekNight.aspx

Picture posed by model.

So, I had this plan to make a line following robot. I’d even figured out how to do the lines. The idea was to print track segments on A4 pages, and then laminate the pages and lay them on the floor. The robot would go from page to page and it would all work.

That was the plan.

So I drew out some track segments in Photoshop Elements, printed them out and then laminated them. Then, and only then,  (and this is the stupid part) did I get round to testing my track design with the robot sensors. Turns out that the line sensors can see white paper really well. Really, really well. I get 99% reflection when I put the robot on the white parts of the paper. Only problem is, I also get 99% reflection when I put the robot on black parts. This is not a problem with the laminate,  it seems that, as far as the sensor is concerned, black is most definitely not black. Robot fashion shows must be awfully dull.

Anyhoo, my line following plans were in danger of not being plans any more. Finally I had a brainwave. Carpet seems to give me only around 20% reflection, even through plastic. So I’ve now made some track parts that just have transparent sections where the dark bits should be. You can just see how this works in the corner section above. The green LED is lit because the sensor at the far side of the robot is on the white part.

And now I’ve hit another snag. The robot runs rather roughshod over the path sections. I was hoping they would be heavy enough to stay put when the robot goes over them, but it seems that Jason is rather heavy footed, and messes them up. I’ve now got to find some velcro, or something that will stop them getting moved around as the robot travels over them.

That’s for tomorrow though, I’m off to bed now.