Pololu 3pi robot

The popular 3pi robot from Pololu Robotics and Electronics is a small, high-performance, autonomous robot designed to excel in line-following and maze-solving competitions. Powered by four AAA batteries (not included) and featuring a unique power system that runs the motors at a regulated 9.25 V, the 3pi is capable of speeds up to 100 cm/second while making precise turns and spins that don’t vary with the battery voltage. This results in highly consistent and repeatable performance of with well-tuned code, even when the batteries run low.

The robot comes fully assembled with two micro metal gearmotors, five reflectance sensors, an 8-by-2 character LCD, a buzzer, three user pushbuttons and more, all connected to a user-programmable AVR microcontroller. The 3pi is approximately 3.7 inches (9.5 cm) in diameter and weighs 2.9 oz (83 g) without batteries.

The 3pi is based on an Atmel ATmega328P microcontroller running at 20 MHz with 32 KB of flash program memory and 2 KB of data memory. The ATmega328P microcontroller makes the 3pi compatible with the popular Arduino development platform. Free C and C++ development tools are available, and an extensive set of libraries make it a breeze to interface with all of the integrated hardware. Sample programs are available to show how to use the various 3pi components, as well as how to perform more complex behaviours such as line following and maze solving.