At 64 years of age I am finally building my own robot! The first robot I saw was Mr Robotham at the Schoolboys Own Exhibition in 1955! (Google images will find it for you.)
My idea is an arduino based platform with a variety of environmental sensors. Construction is underway (No pics yet I lent someone my digital camera and tripod!) chassis is built from plain perfboard (means everything can be based on 0.1" units with simple drilling & alignment) and right-angle pvc extrusion. Movement comes from a pair of TowerPro 9g servos modded to continuous rotation (real pain if you have sausage fingers, and I am waiting for a couple of replacements for the one I damaged). Software seems to be working ok for drive. Obstacle avoidance will be ultrasonic ( I have the module but not tried it yet).
All ideas gratefully received.