Fence Following by an Autonomous Mobile Robot Including Various Intersections

Demands to use washing robots in pig houses are growing up. The robot washes pig beds using a long arm over fences from passages. The passage is narrow so that the robot must detect the fences and run along the fences with high accuracy. A laser range scanner is useful to detect fences because there are many kinds of fences. However, the noises occur to the measured values if there are obstacles behind fences. In this study, the distance between scanned points and a path of robot is calculated and it is utilized with a zoned minimum filter to extract the points representing the fences. Then, the candidate lines are detected from the extracted points by Hough transform to detect multiple fences simultaneously. To run along the fences, the robot calculates the self-posture and distance to the detected fences. This paper describes the above proposed method and reports some experimental results of running along the fences and passing various intersections.