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The internet was off all weekend, made even more annoying by a) their customer service lines were also closed all weekend and b) it came back online first thing this morning meaning when they got into the office and saw the problem, a simple remote equipment reset or similar fixed it in a matter of seconds Still, least it’s working now. It gave me a chance to play with using IR detectors on the Boe-Bot to act as eyes for navigating which was pretty cool:

As opposed to using the wire ‘whiskers’ which have to physically touch an object before then backing up and moving away, and the light-sensitive photoresistors which weren’t really useful for navigating around objects at any great speed, using the IR sensors allowed it to continually send out pulses to detect objects and then react to them before they became an obstacle. This allowed much faster movement through a small maze (another USPS-sponsored event!):

I also set it up using basic code for a sumobot where it would lock onto an object and try to follow. Mia was not impressed! I was though, as it was able to successfully track a very fast moving dog

A little more difficult working with the photoresistors rather than the whiskers as there’s so many windows in this house, it’s very bright at the best of times But, I played around making the Boe-Bot act like a scaredy-cat by backing away from a flashlight:

More useful was programing it to move towards light sources, such as exiting a dark area or room and moving towards the light – of course, Mia decided to come stick her nose in again! Think I need a subroutine called “DogAvoidance” (maybe use the piezospeaker to emit a high frequency tone!), but it seemed to do pretty well on this one anyways:

And one more project to have the Boe-Bot detect changes in the colour surface and avoid black areas.

One common robotics challenge is following a black line, so I’m guessing this is something the textbook will move onto using the same principles of detecting the colour changes and making adjustments as to the direction of travel. Next up though is using the infrared sensors for navigation and object detection.

This afternoon I worked through using ‘whiskers’ on my Boe-Bot so that it can detect when it’s touched an object and so backup and try again in a different direction:

It was a little more interesting than the first few chapters of programming it to move in certain directions, turn at a particular angle, etc. although probably worthwhile in the long run to be able to calculate what speed and durations of turn produce various distances and directions. After setting up a minor obstacle course (sponsored by the US Postal Service…), Mia decided to come and see whether anything good was happening:

Inquisitive little bugger…

Note: I’m switching some videos to YouTube as the media plugin I use for WordPress automatically starts downloading all videos displayed which is getting boring if there’s more than one video to load. For those at work, school, college, etc. where YouTube may be blocked, I’ll be including an alternative video link here on the blog below each YouTube clip, ‘cos I’m nice

Robotics is something I’ve wanted to get into for years, pretty much since Robotwars appeared on TV and the idea of creating big machines with flames coming out the top that were designed to smash other machines sounded like fun I raced various forms of remote controlled cars on + off for a number of years, but that was mainly build the cars, then set them up from race to race. But, programming a microchip and building a robot to figure it’s way through an obstacle course or similar seems like a good challenge, and then there’s stuff like the RoboGames each year (along with smaller regional gatherings) which includes events for small sumo-bots or robosoccer (check the videos!).

Anyway, Parallax caught my attention a while ago with their Boe-Bot robotics kit based off a BASIC Stamp 2 microcontroller and mine arrived today. It seems a pretty good introduction to robotics, and the BS2 chip can be used for a bunch of other things too. Parallax make all their books available on-line in PDF format, so also I’ve worked through some basics with using the BS2 chip outside of controlling the Boe-Bot. With a number of projects included with the kit and components to allow the robot to make it’s own decisions based on position, speed, contact with objects, etc. it should keep me entertained for a while. When I have the rest of the circuitry built up and programmed for something slightly more advanced than moving backwards, forwards, and rotating around itself I’ll post some photos or videos

Using it within OS X was a little harder than inserting the CD and installing the software as Parallex don’t produce their programming suite for OS X or Linux, but others have written apps available for free online which work great. For anyone trying to use the USB version under OS X, download the FTDI VCP drivers here and then install MacBS2 by Murat Konar which is the equivalent of the Parallex programming tool for Windows. For code requiring user input using DEBUGIN, goSerial from Furrysoft works great for displaying the output the same as Debug Terminal does, but also capturing your inputs and sending them to the BS2 chip which MacBS2 can’t do yet. Simply select your USB connection under the ‘Serial Port’ option in goSerial, and then choose ‘9600 bps’ for the connection speed and it should work just fine so long as you close down MacBS2 first otherwise you have both apps trying to connect to the same port concurrently.