Hi LMR, first of all I'd just like to thank all of you for this awesome site - I could never have got into robotics if I hadn't discovered this!
Anyway, Alfie is my first ever robot, and although I have done a little programming before, he is also my first experience with electronics, soldering, all of this stuff really. I kept him fairly similar to the start here robot, just omitted the servo and added a downward facing sensor so that he doesn't fall of tables. The chassis is made out of plexiglass/acrylic/whatever you care to call it. I made the mounts for the motors and the SRF05 out of some little bits of scrap metal I had lying about. It's not terribly neat as I used my dad's virtually blunt hacksaw to cut everything, and most of the screws don't quite fit as they were salvaged from various broken electrical appliances that I took apart.
As I had never soldered before, I was a little nervous about ruining the circuit board and dripping hot molten solder everywhere, but it was actually alot easier than I anticipated and everything went very smoothly. The programming was very simple as I didn't want to try anything too complicated on my first robot.
By the way, on the first part of the video, Alfie judders a little when going backwards, as I hadn't yet fixed a slight problem with the wheels. This is fixed on the second part.
Pictures are below -
all the stuff :-)
assembled the base
soldered pins
attached the board
attached the wheels
finished!
Avoids obstacles, tries not to fall off tables
CPU: Picaxe 28x1
Power source: 3 AA's
Sensors / input devices: Sharp IR, SRF05 Ultrasound
Looks really clean and slick, well done on your first robot
A good way to upgrade it, if you want to keep working on it - mount the distance sensor on a servo, so it can detect obstacles in a wide angle. With good programming you can get it to move around like a pro, smoothly curving it’s way around any obstacle
Thanks for your input - I did originally buy a servo and was planning to use it in the way that you suggested, but unfortunately I managed to fry it (don’t know how!) and my budget wouldn’t allow me to get a new one. I may try again in the future though.