On-Line Optical Flow Feedback for Mobile Robot Localization/Navigation. (May 2003) David Kristin Sorensen, B.S., Texas A&M University Chair of Advisory Committee: Dr. Sooyong Lee Open-loop position estimation methods are commonly used in mobile robot applications. Their strength lies in the speed and simplicity with which an estimated position is determined. However, these methods can lead to i...

We describe in detail a novel kinematic simulation of a three-wheeled mobile robot moving on extremely uneven terrain. The purpose of this simulation is to test a new concept, called Passive Variable Camber (PVC), for reducing undesirable wheel slip. PVC adds an extra degree of freedom at each wheel/platform joint, thereby allowing the wheel to tilt laterally. This extra motion allows the vehic...

A challenging problem faced by wheeled mobile robots (WMRs) such as planetary rovers traversing loose sloped terrain is the inevitable longitudinal slip suffered by the wheels, which often leads to their deviation from the predetermined trajectory, reduced drive efficiency, and possible failures. This study investigates this problem using terramechanics analysis of the wheel-soil interaction. F...

Most vehicle transmission systems control the ratio between engine speed and wheel speed using a fixed number of metal gears; the Continuously Variable Transmission (CVT) in currently available vehicles utilize a pair of variable-diameter pulleys connected by a belt or chain that can produce an infinite number of engine/wheel speed ratios for improve fuel consumption, drivability effectively, a...

In this paper, a robust wheel slip control system based on a sliding mode controller is proposed for improving traction-ability and reducing energy consumption during sudden acceleration for a personal electric vehicle. Sliding mode control techniques have been employed widely in the development of a robust wheel slip controller of conventional internal combustion engine vehicles due to their a...

for the ICRA08 Planetary Rovers Workshop Slip Estimation and Compensation Control for Lunar/Planetary Rovers on Loose Soil Kazuya Yoshida, Keiji Nagatani, Genya Ishigami Dept. of Aerospace Engineering, Tohoku University, Japan Giulio Reina Dept. of Innovation Engineering, University of Salento, Italy For a mobile robot, it is critical to detect and compensate for slippage, especially when drivi...

A wheeled ground robot was designed and built for better understanding of the challenges involved in utilization of accelerometerbased intelligent tires for mobility improvements. Since robot traction forces depend on the surface type and the friction associated with the tire-road interaction, the measured acceleration signals were used for terrain classification and surface characterization. T...

This paper investigates kinetic behavior of a planetary rover with attention to tire-soil traction mechanics and articulated body dynamics, and thereby study the control when the rover travels over natural rough terrain. Experiments are carried out with a rover test bed to observe the physical phenomena of soils and to model the traction mechanics, using the tire slip ratio as a state variable....

This paper discusses the development of an optimal wheel torque controller for a compliant modular robot. The wheel actuators are the only actively controllable elements in this robot. For this type of robots, wheel-slip could offer a lot of hindrance while traversing on uneven terrains. Therefore, an effective wheel-torque controller is desired that will also improve the wheel-odometry and min...

Much research on two-wheeled robots has been completed in the past decade, but robot stability in low-traction environments has not yet been considered. A model for the two-wheeled robot including wheel slip effects is derived. A wheel slip dependent friction model is used to simulate two low-traction surfaces: the first has characteristics similar to ice and the second is frictionless, in addi...