A surface clinging robotic device. The device includes a supporting structure or base, on which is mounted (a) a lead pivoting support surface, such as a pivoting wheel, and (b) two or more traction drives, such as drive wheels. Each of the traction drives are independently driven by a separate drive...http://www.google.com.au/patents/US7280890?utm_source=gb-gplus-sharePatent US7280890 - Method for fabricating sliding vacuum cups
