Starting my first scratch built robot
April 12, 2010
Very informative forum you have here. I have been lurking for a couple of weeks and decided it was time to join up.
I built my first and second robots about 4 weeks ago from an I-Box "Robo-Box" kit, an O2 obstacle avoider, and a "NanaTank" edge detector. I later modified them to be line followers and object seekers and pushed the limits of the RoboBox controller. It seems like the Robo-Box LogoCricket microcontroller is sort of a dead end, but good enough to get started. I learned some elements of programming, played with infrared sensors and line following. Had a bit of difficulty because I switched all of our home computers to Ubuntu last October only to find that I could not make the CricketLogo IDE run under Linux or WINE.
I ended up resurrecting an OLD PC from a garage sale just to have a Win2k box to program the robot. Actually that worked out OK because I was never able to get the USB to RS232 adapter to run properly, so running from a real serial port helped alot. Eventually I hope I learn enough to install a different microcontroller chip in the I-Box...maybe something that will do C++. Anyway, the RoboBox kit came with a really nice set of sensors and building components that I can use on future robots, so I remain quite satisfied with the kit even though I have already outgrown it.
My third robot is on the boards. It's a "Sandwich" line follower from David Cook's Robot Building For Beginners. I'm really enjoying building this robot with the Solarbotics parts pack, and I highly recommend Cook's book for anyone who is starting out in robotics and who knows little or nothing about electronics. Even though I knew slightly more than nothing, the book has been a great teacher about things like how to use a comparator, how to calculate and measure voltage in a voltage divider circuit, how a transistor works, and how to really use my digital multimeter. I dug out my soldering irons which had been in boxes for about 25 years
My SANDWICH is not yet complete, but I have all the circuitry running well on a bread boad and am in the process of transferring it to the PCB. Meanwhile I take a break from the electronics by building up the chassis. The last step will be to mate the "body" with the "brains", and for that, I am waiting for a package of Molex connectors I ordered from Jameco. I want to be able to easily swap out things like controllers, motors, battery packs, sensor packages and so on, so it seems logical to me to start out right away by using Molex connectors to connect any component that is not mounted directly to the PCB. Eventually I think I'll want to replace Sandwich's primitive brain with a microcontroller and I want to be able to do that without having to unsolder anything.
Anyway, I can see the light at the end of the tunnel for my Sandwich, so it is time to start planning my fourth, and all of the skills and knowledge I gained from my first three robots are now coming together as I plan my. I found an article on SERB, a servo powered, Arduino based robot. I toyed with the idea of buying the kit, but decided that it was a bit pricey. Instead I downloaded the cutting template and am having a friend who is good with a scroll saw cut the chassis components for me from acrylic sheet. I've been fooling around with an Arduino for about 6 weeks and learning a lot from it, so I think I will build another Arduino and mate it to a small breadboard to create a simple platform for experimenting with the the Wiring and Processing dialects of C++, and using Bluetooth, or something, to send sensor and maybe even mapping data back to a PC .
Anyway, I really enjoy reading about everyone's projects on this forum.