The R2 unit is one of the most ambitous projects Ive worked on. It features a sophisticated sensory array located in a movable head unit, foot mounted collision detectors, a cordless vacuum cleaner, and best of all speech control. I built it to look like R2-D2 from star wars and be functional at the same time. I have programmed it to perform different functions such as vacuuming, whilst avoiding obstacles and tracking moving objects. The routines mentioned are selected by the operator saying the appropriate commands. Technical specifications: Hardware build time: Year and a half and still adding bits. Software build time: I develop new programs for it all the time. Cost : Motors £30.00 Electronics £20.00 Vacuum £20.00 Power : 9.6 volt NiCd runs for over 30 mins! Speech software : Microsoft speech SDK Language : Borland Turbo C and Visual C++ Email: c6jones@plymouth.ac.uk