In this paper, an algorithm for a dynamic base real-time kinematic (DRTK) GPS is presented and a novel application to the guidance and control of a mobile robot pulling a trailer is discussed. The DRTK system is used to estimate the relative position between the robot and trailer in the autonomous system described, and the results are compared to traditional methods utilizing an optical encoder. Geometry error is analytically predicted and the influence on trailer position is shown. Experimental results show a marginal accuracy improvement over a properly calibrated encoder based system but a significant improvement when calibration errors are present.
In this paper, effects of sensor location and measurement errors on path tracking control of a mobile robot pulling a trailer are reported. A model for a two-wheeled robot towing a trailer is presented, followed by a state feedback controller designed to position the trailer along a path consisting of lines and circular arcs. An incremental encoder is used to measure the hitch angle between the robot and trailer. A combined GPS/IMU system is used to measure position and orientation of either the robot or the trailer (but not both). The choice of mounting location for the GPS/IMU system, and consequent effects on trailer path tracking performance are explored. The sensitivity of the system to hitch angle errors is also examined for both cases. It is shown that the system is less sensitive to errors in the hitch angle measurement when the GPS/IMU system is located on the trailer.
A GPS based automated convoy strategy to duplicate the path of a human driven vehicle is presented. GPS carrier phase measurements are used to estimate a relative position vector with centimeter level accuracy and changes in relative position with millimeter level accuracy. These estimates are used in the presented method to enable a following vehicle to replicate a lead vehicle's path of travel while both are in motion and not necessarily in sight of one another. Results from a real time implementation are given. Error analysis reveals path following accuracy is a function of following distance. Real time performance is compared to the derived theoretical accuracy. Discussion within explains deficiencies in ''breadcrumb'' waypoint following, limitations of the proposed method, and suggestions to enhance performance through augmentation with other on board systems.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.