Over the summer we installed hardwood flooring – which needs constant sweeping and cleaning . What to do… What to do… Well, most of us would just sweep it, right? Some of us might even go buy a Roomba. But, then again, some of us build something to do it for them. Why? Because we can…
Pulito (Italian for ‘clean’) is simply put, a sweeper robot. Much like a Swiffer and Roomba combined. The intent was to build a robot that could navigate around sweeping hard surface floors, stay away from carpeted areas, make its way under our couches and seek out a docking station when the battery runs low.
After I had success with my challenge to build a 1″x1″x1″ NanoBot, I wanted to try my luck at something a little larger. MicroBot measures approx 2″x2″x1.5″ and uses the same Atmel microcontroller and battery (see NanoBot details). The body was custom made from a larger piece of 4mm white PVC. MicroBot gets its’ senses from 3 front mounted ProxDots (IR units) and a bottom mounted IR unit (for line following). This gives MicroBot the ability to detect left, center and right objects and to react accordingly. The drive motors are self contained units pulled from some old LS120 laptop disk drives. The motors are used to eject the disk so they have a great amount of torque for their size.
While waiting for the NXT system to come out, I decided to try my luck at making tiny robots. While Googling, I stumbled across a Yahoo newsgroup for NanoBots based on the MegaBitty controller. I have always been interested in making compact Lego robots, but for obvious reasons, they can only be so small. So, I decided to try my luck and NanoBots. Although I am not sure of the exact definition of a NanoBot, I believe it has specific maximum size limits for competition which is approx. 1 inch cubed (1x1x1). This is my first venture into non-Lego robots. NanoBot uses a variety of pico-sized components including:
Atmel Mega 8 Microcontroller
2 GWS Micro Servos – hacked into the gearbox below.
A 3.5V IPOD Shuffle battery unit w/built-in charger.
CJH line and object sensing base and front circuit (uses SMT components)
None other than Lego minfig wheels
Some of the key electronic components used on NanoBot are:
AtMega8P main CPU (IC AVR MCU 8K 16MHZ COM 32-TQFP – ATMEGA8-16AC)
Photointerrupter Line sensor (x2) 424-1096-5-ND
All caps, resistors, LED’s are surface mount technology (SMT)
The BluBot was designed in part to meet some of the challenges that have been discussed on R.T.L etc.. The idea is this:
The BluBot will move around an arena in a random manner until the light sensor detects a yellow ball (reading 44-50).
If the ball is not yellow, BluBot will backup, turn and continue. If it is yellow, BluBot will drive forward to collect the ball. Once the balls have been picked up, BluBot sets out to seek the black line around the arena. Once it is found, BluBot starts a line-following algorithm. Once the main drop-off is reached the kicker will engage and dispense the balls into the holding area. The method in which this is done can be better seen below.