The Bristol Robotics Laboratory at the University of Bristol, UK has built a robot that senses obstacles not with cameras, but sensitive whiskers at the front end:
Researchers at the University of Bristol in England hope to deploy the poodle-size ‘bot in search-and-rescue missions where vision is impaired, like in mines or smoky rooms. Its 18 whiskers move back and forth five times per second. When a whisker bends, a sensor on its shaft signals software to orient the ’bot toward the object. Whiskers close to an object move less, while those farther away make wide, sweeping motions to establish the object’s exact edges.
http://www.popsci.com/bown/2009/product/scratchbot | Bristol Robotics Laboratory