To effectively and timely collect production related information to support precision farming decision-making, an autonomous watching-dog robot has been developed to collect field information automatically. This autonomous field watching-dog robot is equipped with a camera and a GPS receiver to find and locate unhealthy crop and/or weeds in the field. A SICK laser measurement system is used to guide the watching-dog robot traveling between the rows of crops autonomously using four independently driven and steered wheels. A magnetic compass was used to sense the direction all the sensors and wheel controllers are connected using CAN bus. This paper reports the control system development for performing autonomous field data collection using this field robot. Field tests will be conducted to verify the effectiveness of the control system.