Steering Panning Coordination In Stereotyped Motion

Abstract

Problems of vision-based mobile robot are (1)How to stabilize visual images swinging right and left, up and down, in running on irregular road surface. (2) How to pan and tilt TV camera to take visual informations from environment for mobile control. To solve these problems, vision-based and sensor-based stereotyped motions are proposed and implemented on mobile robot Harunobu-4. A stereotyped motion is defined by a fixed steering control pattern of undercar- riage in coordination with a panning/tilting control pattern. Field tests were done in campus road. 1. Introductan We have been developing self contained mobile robot Harunobu-4 based on a strategy stereotyped motion by sign pattern(l,2). To move a side walk or campus, Harunobu-4 is made smaller in size than VaMoRsl31, Navlabl41 and ALVin(51 which run highway or all terrain. From size limitation Harunobu-4 equipped with a MCG8020 micro computer system including a color image frame memory of 512*512 pixels connected to a commercial TV camera of domestic use. Problems of 'l'V image based robot is as follows. (1)How to stabilize visual images swinging right and left, up and down, in running on irregular road surface. (2) How to pan and tilt TV camera, because effective vlsual field of TV camera is in the utmost 40 degrees in horizontal angle, it cannot cover the visual field necessary to drive the mobile robot. The robot has to pan and tilt the TV camera to take necessary information from environment. Some fixed pan/tilt control in coordination with steering control is desired to allocate limited imaging resource. To solve these problems, several fixed patterns of steering in coordination with panning and tilting pattern are specified.