Construction Vehicle Navigation and Automation

摘要

Today, earthmoving machine operators receive their information and instructions through an intermittent, manpower intensive, and costly process. The process typically begins with a survey of the site, accompanied by the identification and location of natural and man-made structures. Working with this information, the planning engineer designs the project. These designs are transferred to the field by another survey, with survey stakes located and marked at key locations. Hundreds or even thousands of stakes defining elevations and grades may be required. Furthermore, field foremen and paper plans usually supplement the survey information. As the job progresses, additional surveys may be required to convey information on the next phase, to make changes to the current work, and to document completed work against plan. Not only is this process time-consuming and expensive, it contains numerous opportunities for error. The U.S. Army Topographic Engineering Center (TEC) and Caterpillar Inc. have cooperated in the joint research and development of a system to position, track, and maneuver construction and other equipment during their normal construction activities. The two main components of this research focus on the positioning system needed for navigation and the Computer Aided Drafting and Design (CADD) interface for automation. The positioning system is based on software developed by TEC that utilizes the Global Positioning System (OPS). It is called the On-the-Fly (OTF) Differential GPS system. Several repeatability tests were conducted to test the accuracy and precision of the OTF software. The results proved that the OTF system can provide an accuracy of 3 centimeters in a robust manner.