Simple and complex obstacle detection using an overlapped ultrasonic sensor ring

This paper presents both simple and complex obstacle detection using an ultrasonic sensor ring with overlapped beam pattern. It is assumed that a set of ultrasonic sensors of the same type are arranged along a circle of non-zero radius at regular spacings with their beams overlapped. To assess the positional uncertainty of an overlapped ultrasonic sensor ring in obstacle detection, the obstacle distances of three adjacent ultrasonic sensors are compared. First, the positional uncertainty for single obstacle detection can be determined based on the combination of ultrasonic sensors detecting an obstacle. Second, the positional uncertainty for multiple obstacle detection can be determined based on the inequality relationship among three adjacent obstacle distances. Third, the positional uncertainty for omnidirectional obstacle detection can be determined by overlapping all the uncertainty arcs obtained for every three consecutive ultrasonic sensors.