[Animats]

Would somebody please develop a modern sonar system for low-end robotics? Those guys are using sonar sensors from the 1980s. They give you the range to the nearest thing in a cone about 90 degrees wide. They're from an obsolete generation of self-focusing cameras. There's been some progress since then.

Robot sonars should have capabilities comparable to bats by now. You've probably got at least an ARM processor available. There's a startup trying to do this (http://www.chirpmicro.com/) for mobile gesture recognition.