Video Clip of Leo

Leo's Maiden Run. Here's the link as promised. After he rounded the corner he got stuck in one. Time to work on sensors and upping his battery supply.  I may go ahead and put a low voltage sensor on his battery packs, so that I know when he's running low or just stuck.

Yay!

Leo now has front bumper switches! Now just need to attach the bumpers and work on the rear bumper. I've even got the bumpers coded. I did check mouser.com for the bipolar hall effect sensors, and they don't keep them in stock. So, I'll have to scrounge ebay for them, yippee. After I get the bumpers completed, I will start on the IR rangers. That should keep me busy till the hall effect sensors come in.

The trip to Frys

What a disappointment the trip turned out to be. Mostly bare shelves, no ICs that I needed nor that anybody else has needed in some time. Picked up some resisters, some caps, and some diodes to play around with, though. Still need some different resistors and caps, along with diodes and other discrete components. I also got a small solderless breadboard. Ah well, BGMicro.com here I write. No motor drive components or real sensor work till after I get the ICs in.

Got the arduino board in today

Well UPS came by at 4pm finally, waitied around all day for the delivery. Got the board out, installed the drivers, and did my first 'sketch'. Tinkered with it quite a bit. It did provoke a few thoughts, such as how to save data? Only a computer that is easy, you just make a file, but the AVR doesn't seem to have a system for that. I'm going to frys tomorrow to get parts for the L293, the 38mhz oscillator circuit and some pull down resisters for the bumpers. May get a few sharp sensors if they have them and some IR LEDs too, I need to start working on the body now that a few parts are available for size purposes.

In possession:

Tracked Bulldozer Body
AtMega328 (yay!)

End of August goal:

Get the AtMega328 mounted into the modified tracked drive

End of September goal:

Get both motors and all sensors operational

I will post a full progress report once a week

Some decisions

I've been researching a few different avenues and decisions. First decision was I didn't want a prefab bot, not really interested in being limited by somebody else's design parameters. I don't want a huge body, nor something tiny, and not something expensive either. On the processor front, I thought about the Parallax stamp modules, 68HC11 and propellor, I have some experience with the 68hc11 series and I know that there is C compilors for them, so that's a plus.

So here's where the decisions stand today are:



Body Type : Tamiya Power Shovel/Dozer Model Kit ($29.99 and already had it)
Drive Type : Tracked (included on the body)
MCU Type : 68hc11 series
Battery Type : Lithium Rechargeable(plenty around here and not expensive)
Sensors : Encoder on the tracks, front and back bumpers
Actuator : N/A (though I think with a bit of tinkering the dozer apparatus might work)
Language : C based and free would be even better

Decisions yet to be made:

Board Type : Fingerboard, Handy Board from M.I.T., HC11 EVB {Mainly need/want 64k mem and lots of I/O)
Body Modifications : Do I keep it the way it is, do I make the bottom more into a box to house 'brains' and batteries?

Research to do

Figure out which boards have the option for 64k ext mem and lots of I/O
Bumper types and schematics
H Bridge (DPRG.org)

Shopping List


Cheap Mouse for encoder wheels and sensors (<$5) (frys.com)
1/4inch thick pine board( 1", 2" and 3" wide and various length) (homedepot.com)
Sandpaper 400 grit to smooth edges (have around here)

By the way, I did join the Dallas Personal Robotics Group mailing list. Will have to shove some money into paypal to get full membership.