Older blog entries for robodave (starting at number 4)

Uhh, diary? What's that? Something tbat should be regularly updated? Maybe I'll learn that eventually. Let's see, another Roborama, definately wasn't prepared, cool robots there. Some Austin guys came by, one had a really cool kind of trolley advancing biped. One "foot" would bear dowm under the weight of the batteries/processor while the other swung around. The barreries/controller would then trolley over to stop on the other foot, dropping it while raising the former, pretty cool. And the awesome running of Dave Andersons 2 wheel balancing Nbot. An autonomous Segway essentially. Simply amazing watching it make it's way across the course. Lotsa good competitors. Another Robothon, wasn't ready then either. But more cool robots, a little tiny (about a cubic inch, maybe a little more) M&M color sorting robot, sorting them into piles all day. Lots of minisumos, sumos, line followers, floor excercise robots. Another DPRG Tabletop contest, Sarge no longer reigns supreme over the minisumo ring of Dallas. So I guess I gotta build another one.. And get ready for Roborama September 21. And figure out the new IsoPod I've been playing with.. And try out the STK500 I got. Amd make a biped.. and.. What was I saying about writing in a diary again?

Ya know, I really should update this more. Been through the Roborama 2001b and Tabletop contests, built 2 new robots, and have been trying to get a simple AVR circuit working. At any rate, recently was the 3rd Tabletop contest for the DPRG, had a lot of fun, and even did well! I need to remind myself to quit trying to get the robots working the night before the contest. Sarge won in the Minisumo contest, luckily this time since there was some pretty stiff competition. New robot Stingray even won TT Quicktrip, though the IR sensors were picking up all sorts of wonderful noise from the flourescents at BPI. Didn't even try the Line following, as I knew that Stingray was just a bit too fast to reliably stay on the line.

About Roborama, new robot Scooter did ok, but showed those programmed-the-night-before actions. It almost worked in line following, wasn't even going to leave that line, bounced a wall in Quick Trip, and finally finished T-Time, also with a wall touch. Definately needs work, especially if the CanCan contest is to be attempted. But Scooter is definately a pretty good base, Stingray might need some improvements (perhaps a hard drive platen for a base?)

Over the summer, got to visit the MIT Leglab in Boston, really cool toys, even some pics! And have been trying to update the DPRG contest pages to help Eric some. Feel a bit inadequate to the webpage stuff, but will also be trying to get some picture pages together for the 2 Roboramas this year.

Finally relaxing after a really cool weekend. I went to the Seattle Robothon! And it was really great! Robots and geeks and demos, oh my! And another Dallas guy went too! He brought his pretty sophisticated robot to give a demo and enter the Floor Excercise, while I was just there to absorb and enter the MiniSumo event. My robot Sarge 2 (new pics on the webpage) didn't make much headway through 28 other competing minisumos, won 2, lost 2 (double elimination, man, my robots first loss was to a teenage girls robot :), but that was of course Isa Harrison), but it was really fun, informative, and the event is a pretty good crowd pleaser. There were 2 robots in Fire Fighting (tough contest), 6 in full Sumo, 4 in Grand Maze, 7 or so in Line Maze, and probably 8 in Floor Exercise. The crowd seemed to enjoy the sumo events and the floor exercise, a general demo of a robots capabilities that may not fit a given contest. The robot builders enjoyed it all, and the mass of tables of robots really provided a good display of interesting tech. Sony was there demonstrating Aibo (old and new) and a pretty cool robot part seller Acroname displayed and sold their wares. There was also Zorinco(?), Lineo, maybe Newton Labs? FIRST robots, BEAM bots, fascinating devices everywhere. A lot to take in, even in the 8 hours alotted. Even met some "famous" people. And an incredible organizational effort. All in all, probably at least 100 robots, 30+ competitors, + another 20 general robotheads, and a crowd actively observing at any one contest perhaps 80+, perhaps a few thousand over the day just wandering through the various displays. One main organizer, 3 or 4 announcers, 8-12 judges, 2 or 3 registration/sales, with everyone rotating in and out of other jobs and some of the people even got to compete in other contests they weren't involved in. Great location. And you know, they're already reserving space for next year. Why am I thinking like this? Dunno. Perhaps to see what is needed to put together a large event. I often wonder why some of the former DPRGers left, see some of them here. Just random thoughts. And a dang long entry.

Ok, here it is, just a few days before Roborama, and I've been dragging my feet getting something together. So over the past few days I've been putting a NEW robot together, instead of improving the old ones. The whole idea behind building a power booster was to give Robosnail a kick in the pants, a little more speed with a little less weight. But that's been sort of abandoned in favor of building a new one with (drumroll) Billy Bass motors! The platform is there (small sheet of plastic), battery is on the underside, motors with wheels mounted, little rear castor mounted, Homebrew Basic Stamp 2 mounted, IR sensor mounted. It feels pretty fragile, but it should work. Don't ya just love super glue, velcro, a few small bolts, and PC mounting standoffs? Need to solder leads to the motors to connect to the h-bridge (754410) to be mounted, get the cheap sonar circuit together (a few transistors and parts to drive a camera pull sonar board), check out the line sensors. And write a little code. How will left/right IR proximity detectors, left/right line sensors, and the not yet finished sonar work together? (may skip the sonar) How to make it look pretty instead of a mass of wires? (may just decide to frighten small children) Think I'll call it B-B- Bot maybe, at least until a better name comes to mind.

Things to come: finally have what I believe to be the appropriate parts for a voltage booster, but need to take the time to wire it up. Trying to boost 20 volts to 36 with a 400 mA or more draw, using an LM2577. It'll hopefully give a little speed to Robosnail in competitions. Also need to put in pull-ups for the LM339 for Sarge that I forgot. (oops). And wire up the interface for the camera sonar board sometime soon. And learn more IntelliCAD. And try schematic of more than one chip on Eagle.

Observed: Those cheap ($25) new Devantech sonars look pretty cool, but about a third the range of a Polaroid or hacked. IR is iffy in the flourescent rooms, even with the modulating detectors, might try some exposed film or remote covers on next DPRG trip. Big PID discussion coming to an end on SRS list. Position control, yes, using locked antiphase PWM. Got new toys, Pittman GM9234C212-R3, but need to make sure what 500 cpr encoder is on them as well as possible over torqueing of gears.

Man, long entry, but hopefully a start.

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