NOTE: the iRobot Create platform uses an ATmega168 chip which only has 16K of programming space but same amount of I/O pins as the ATmega328.
32K of program space. 23 I/O lines, 6 of which are channels for the 10-bit ADC. Runs up to 20MHz with external crystal. Package can be programmed in circuit. 1.8V to 5V operating voltage!
- Arduino - DIP connector (plug/unpluggable) to ATmega328
64KB Flash, 4KB EEPROM, 8KB SRAM, 58 I/O Total
- Axon II - board for the ATmega640
These are a full computer on a board the size of a pack of gum. They are either 400 Mz or 600 Mz, run linux, and use an SD card instead of a hard drive. They have a full line of add on boards to do things like motor control, video capture, and wireless communication. Details here
Sabertooth dual 5A motor driver
Drives 2 brushless motors. Need more than one for multiple motors.
Servos are moters that have a gear box, encoder, and control electronics included.
Good list of servos from Pololu (big and small) ... but expensive
3$ mini servo (eat that Pololu ;-)
Wireless UART from point-to-point.
The original XBee 1mW has limited range but easier to set up.
The XBee 2mW Series 2.5 is more configurable (can create mesh network) but is harder to set up.
Cell Phones Integration
Using a cell phone as the brains of a robot has always appealed to me. It allows you to have an integrated touch screen interface, rechargable power supply, high level processing, and communications capabilities all rolled into one package. I did this with a couple of projects using my windows mobile smart phone. Unfortunately those have fallen by the wayside ... on to greener pastures:
CellBots : The robots look pretty lame, but the phone integration is great! Check out the neat integration with Arduino. The HTC connector kit is really nice too.