Duane Bennett

Design and Control of the Ball Wheel Drive Mechanism for a Robust Omnidirectional Wheeled Mobile Platform

This paper discusses design and control of a new ball wheel drive mechanism for a robust omnidirectional wheeled mobile platform. This platform is designed for use in the highway maintenance and construction area, which is a generally an unstructured and congested environment. The proposed ball wheel mechanism can move in all directions on the plane, instantaneously and isotropically. Other novel features include: active regulation of traction drive contact pressure and an optimally controlled reconfigurable drive system.

Automated System for the Replacement of Raised Pavement Marker

Raised pavement markers are used to delineate roadways because they provide excellent visual, tactile, and auditory feedback to drivers. However, over time, markers can become dull or detach from the road, which necessitates their replacement. New markers must be placed relative to the existing installation, and this has traditionally been done manually while riding in a specially equipped truck. In order to improve cost-efficiency and worker safety, this paper presents a system designed to automate the replacement process. The primary component of the machine is a linear slide, which allows no relative motion of the installation equipment while placing a new marker as the support vehicle continuously moves along the roadway. The carriage on the linear slide is actuated with a pneumatic band cylinder. A laboratory prototype has been developed and fabricated using a conveyor belt to simulate the relative motion of the road. The dynamic model of the band cylinder and carriage is developed and it is verified through experiment. A controller is implemented and the prototype system accurately places markers while the conveyor runs at any speed up to 0.9 m/s (2 mph).