Friday, September 11, 2009
The Robots are Ready!
I have finished building and testing the three base robots for this class. They are built from the design in the Quick Start guide for the Lego 8527 Mindstorms NXT kit. Students will write, download, and run programs for these robots.
The school-club robot gave me some trouble last night. Its memory was missing the "Demo" program that I needed for testing. I did a hard reset (paper clip 4 seconds in the hole below the USB port). The result was, as expected, that the screen was blank and I could hear ticking from the speaker. When I tried to download new firmware, the NXT was not found. I checked the driver, which seemed to be OK. I re-installed the NXT package on my laptop, to no avail. Someone on the RobotC forum suggested I hold the pin in for 20 seconds. That didn't help. Finally, I removed one of the AA cells from the NXT and replaced it after 10 seconds. That was the ticket. The firmware downloaded, and everything was cool, except when I ran Demo, the motors were a little sluggish. Fresh batteries cured that problem. Since the batteries were fresh from last night, and were pretty warm, I conclude that when the NXT brick is in "tick tick" mode, it draws power and doesn't have enough intelligence to shut itself down. So, when in "tick tick" mode and frustrated, pull the batteries before quitting for the night.
This morning I have an ALIR instructor meeting, and I will take some handout pages for copying.
I'm told through the grapevine that there are even more people wanting to take this course. I'm not sure what to do about that, except to promise them that we'll be back next Fall.