Abstract:
This thesis addresses the problem of outdoor autonomous robot localization
for agricultural operations. A 12hp power tiller, commonly
known as the walking two wheel tractor is used as the test platform
after after introducing electrical actuators for its remote and autonomous
operation. The mathematical model of the power tiller has
been developed and simulated in MatLab SImulink. A vision based
outdoor localization system is developed using off-the-shelf electronic
components, and its accuracy has been verified in small agricultural
fields. Visual odometry using a downward faced camera is tested with
better resolution for relative localization, and popular visual odometry
algorithms were tested for speed and accuracy in agricultural
fields. A stereo vision based range measurement system has also been
developed and field tested as an absolute localization system that can
bound the incremental error caused by the visual odometry system.
The extended Kalman filter with measurement gaiting has been implemented
using both visual odometry and stereo range measurement
data. Experimental results verified that the proposed system as an
effective low cost technique for outdoor localization of field robots in
small agricultural fields.