My thanks to everyone who showed up last night. I though we had a pretty good turnout. Greetings to newcomers Marco and Malcolm. Hopefully Malcolm has found our on-line home here. Hopefully Sharon and son will be able to join us next time. Here's a quick summary of the meeting, off the top of my head:
>>> Malcolm showed us some books on the Arduino chip and programming environment.
>>> I went over the status of my quadrotor flying robot, and details on Brijesh's custom designed AVR-based controller board (which I should be able to demo for the next meetup).
Discussion forum for Brijesh's board is here: http://www.rcgroups.com/forums/showthread.php?t=1075426
And here's the project home page:http://sites.google.com/site/pushpakquadrotor/
Here's the do-it-yourself drones page that we talked about:http://www.diydrones.com/
And finally here's a link to the other Arduino based homebuilt quad and its discussion pages:http://aeroquad.info/bin/view
(we played a video from here)http://www.rcgroups.com/forums/showthread.php?t=1066119
Here's the link we looked at for anti-aliasing filters:http://en.wikipedia.org/wiki/Aliasing
For some more details on aliasing, and just about anything related to DSP, I refer you to the excellent free on-line textbook "The Engineer and Scientist's Guide To Digital Signal Processing"http://www.dspguide.com/
Chapter 3 has a good discussion on signal aliasing, and analog filters - including Butterworth and other filter types.
>>> Earl demoed some custom test interface boards that he designed, as well as some AVR & Z8 based boards, including the AVR Butterfly.
>>> Mike demoed his Lego gear train for his automated solar collector project. He's still looking for cheap simple controllers, but the orangutang board looks like it might be a candidate.
>>> Daniel showed us sample Makerbot output forms. Thanks again, Daniel, for hooking us up with the Hive space!
Don't hesitate to email me with other updates, corrections, pics, or anything else you'd like to add.
Let me know if there's any interest to discuss anti-aliasing or other topics and I will prepare something - unless some else wants to volunteer. I do plan to have a control theory tutorial at some point.
I hope to see you all at our next meetup. In general, we will meet on the 2nd Thursday of every month at Hive. However, we can't make it next month on that day, so stay tuned for the next meetup announcement.
p.s. Here's a bonus link. On the last page of my Quadrotor presentation, I showed a chart on the concepts of Mechatronics. This site offers a lot of good information for anyone who wants to integrate electronics, mechanical systems, software, and control systems - such as us robotics folks!http://www.eng.mu.edu/~craigk/mech_notes.htm