A Tool for Range Sensing and Environment Discovery for the Blind                                

D. Yuan and R. Manduchi                                        
Department of Computer Engineering                                    
University of California, Santa Cruz                               
Santa Cruz, CA       95064                                 



Abstract
This paper describes the development of a hand-held environment
discovery tool for the blind. The nal device will be
compose do fa laser-based range sensor and of an onboard
processor. As the users wings the hand-held system around,
he/she will receive local range information by means of a
tactile interface. In addition, the time pro le of the range
will be analyzed by the onboard processor to detect environmental
features that are critical formobility, such as curbs,
steps and drop-offs. In our current implementation, range
is collected by a short-base line triangulation system formed
by a point laser and a miniaturized camera, producing readings at
framerate. An Extended Kalman lter is used to
track the range data and detect environmental features of
interest.                                                                                                  

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