The wheelchair, developed at Saitama University in Japan, uses distance senors to stay far enough to your left as to not get in your way. The robot also watches your shoulders to know which way you may be turning. It is even smart enough to know to follow you single file in a crowded hallway.
Also, more than one wheelchair can follow a single person. No word though on how you get the wheelchair to select who they follow.
The idea here is to use these in hospitals and other facilities where people need care. They are currently being tested in the field.
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