“…Articles describe, e.g., the use of GPS [ 7 , 8 ], WiMAX [ 9 ], 3-D sound, or a magnetic compass and gyroscope [ 10 ]. Static object detection from images is used for avoiding obstacles [ 11 , 12 ], along with ultrasonic sensors [ 13 , 14 , 15 , 16 ], or other sensors using a GIS platform for navigation [ 17 , 18 ]. The latest assistive technologies in development try to offer both functions, i.e., object recognition and navigation, mainly in indoor environments, see e.g., [ 5 ].…”