Automated Machine Guidance An Emerging Technology Whose Time has Come?

Transcription

1 Lou Barrett Page 1 Automated Machine Guidance An Emerging Technology Whose Time has Come? Author: Lou Barrett Chairwoman AASHTO TIG AMG Minnesota Department of Transportation MS John Ireland Blvd. St. Paul, MN Phone: FAX: n/a lou.barrett@dot.state.mn.us Submission Date: August 1, 2007 Word Count: 250 (Abstract) 1245 (Body) Page 1

2 Lou Barrett Page 2 ABSTRACT Automated Machine Guidance (AMG) incorporates the use of a three-dimensional computer models to move or place materials with greater precision. Although the technology has been in existence for several years, its implementation on government-financed civil engineering projects is progressing, but at a slow pace. The goal of this project, is to assist American Association of State Highway and Transportation Officials (AASHTO) members, generally state Departments of Transportation, to make informed decisions on how to implement AMG for appropriate highway / roadway projects. One of the keys to successful implementation is a thorough understanding of the technology; its advantages and disadvantages, how to cope with real and perceived barriers to implementation, availability of electronic data, and precision of the hardware. The (AASHTO) Technology Implementation Group (TIG) team is comprised of various professionals from nine Departments of Transportation, and private industry representatives who have utilized the technology, seen its benefits, and are promoting its expansion. As knowledge is one key to success, the result of research for this project is a collection of information on various issues encountered when a governmental organization is considering the use of AMG, and alternatives to overcome the obstacles. Much of the construction industry is ready to use AMG and proactively support the technology as it results in substantial contractor cost savings. As AMG is refined and utilized in more projects, AASHTO members and other governmental organizations (such as cities, and counties) benefit in lower bid pricing on construction projects where this emerging technology is used. Page 2

3 Lou Barrett Page 3 INTRODUCTION Automated Machine Guidance (AMG) incorporates the use of a three-dimensional computer models to move or place materials with greater precision. Operators receive information via GPS satellite transmitters to determine how much earth to remove or when the correct level of aggregates has been obtained. In other cases, the machine controls the materials moving via computer while the operator simply drives down the roadbed. The potential advantages of this technology include: Minimizes survey stakeout, Saves time and promotes work zone safety, Helps ensure a smooth driving surface. Using the collective experiences of the lead states, the goals of this Technology Implementation Group are: Establish a technical assistance program to work closely with state DOTs who are interested in the use of this technology within the next three years, Conduct outreach program to provide information / guidance to other DOTs to move them closer to AMG technology, Promote the adoption of data standards for 3D models for AMG implementation. BACKGROUND In 2006, the American Association of State Highway and Transportation Officials (AASHTO) selected AMG as a focus technology. The goals of the Technology Implementation Group (TIG) include the promotion and support of rapid implementation of the focus technology, by formulating processes or approaches which are conducive to rapid deployment. The project team is comprised of various professionals from nine Departments of Transportation, and private industry representatives who have utilized the technology, seen its benefits, and are promoting its expansion amongst other DOTs. SCOPE In order to accomplish these goals, research needed to be completed in the following areas: Accurate statistics on the current use of AMG by AASHTO members. Defining and documenting current best practices among DOTs who have successfully piloted or implemented AMG. Determining the decision makers in targeted agencies (both DOTs and contractors) and identifying key information they want to know in order to reach a conclusion about trying or adopting AMG. Identifying actual and perceived barriers to overcome in order to do a trial or to adopt this technology as a standard. RESEARCH METHODS One of the first methods of research is a comprehensive survey of the current state of AMG in all DOTs, which is underway. (Note the results will be included in the final TRB report in Fall 2007.) Two problems have made this research more difficult: AMG is used by contractors under contract to the DOTs, and in some cases, the DOT is unaware or has not documented AMG on all projects. Therefore, the use of AMG on state highway projects may be larger than the data indicates. Within the DOT, the expertise or knowledge of AMG usage may be within the Construction, Design, Surveys, and Contract Administration functional areas. If the survey administrators do not seek out the knowledge staff, usage data may be skewed to non-use. In order to overcome these problems, the project team is focusing on personal contact by DOT members Page 3

4 Lou Barrett Page 4 to increase the success rate of locating knowledgeable personnel and subsequent data rather than utilizing traditional mail or web surveys. In addition to using the survey data as one part of the research, the project team has had formalized intensive discussion / knowledge sharing. It began with a review of AMG projects completed in the states that have successfully piloted or implemented AMG. Technical discussions included type of equipment comparing standard GPS equipment, use of laser augmentation, and total stations. The vast majority of projects utilized GPS equipment as it is more cost effective than total stations. Laser augmentation use was minimal. The vertical accuracy of GPS equipment compared to the tolerance requirements specified by the DOTs is of major concern, although the majority felt the continual improvement in technology will overcome this problem in the long-term. Another major area of concern is the creation of the 3D model and other electronic data. There is a wide disparity in methods, with some DOTs providing models on one end of the spectrum, and contractors building models from paper plan sets at the other end. The availability of electronic data is an integral part of this issue, and again, varies widely from DOT to DOT. Some DOTs supply only paper plan sets, while others provide extensive electronic data. A cottage industry of engineering / survey firms as third party model creators has emerged in several parts of the country and is a viable alternative. It's not necessary for a DOT to select one method of model creation, however, guidelines on the type and format of data that is released to contractors and other organizations needs to be addressed before a DOT launches into full-scale AMG implementation. Another set of valuable data is the advantages and disadvantages of using AMG. Part of the problem is that organizations who benefit from AMG (such as earthmoving equipment manufacturers) market the advantages, while minimizing the disadvantages. Therefore, an integral part of this research and subsequent outreach program is the inclusion of both advantages and disadvantages of AMG. As the project team feels the advantages outweigh the disadvantages and are implementing AMG, a realist picture must be presented for those DOTs still evaluating the technology. RESULTS The potential advantages of this technology include: minimizes survey stakeout, saves time and promotes work zone safety, Helps ensure a smooth driving surface. When applied to the grading process, Automated Machine Guidance (AMG) saves agencies and contractors time and money, enhancing their ability to deliver highways "better, faster, cheaper" -- and safer. The primary advantage AMG offers is improved accuracy of measurement, which in turn delivers myriad benefits. With AMG, the contractor can accomplish work more quickly, safely and efficiently in the field, even with less experienced equipment operators, and the process provides more accurate measurements of work performed, which improves the accuracy of payment. For transportation agencies, AMG-related modeling enhances planning, with less reengineering and reworking from design to the construction process, as well as fewer changes and busts. "As-built" tracking provides an electronic imaging archive for future use in maintenance and rehabilitation, a particularly valuable asset in disaster or emergency reconstruction situations. Labor-intensive basic construction activities, such as staking, are minimized and downstream field inspections and QA/QC tasks are accomplished more efficiently and effectively. The precision of AMG measurement and related modeling aids communication and credibility in the environmental process, smoothing permit relationships. Efficiencies created by the use of AMG also allow agencies to reallocate resources for other needs at a time of critical budget shortages. Agency customers, highway users, benefit from better ride quality due to a consistent subgrade, and AMG-related GPS tools create few traffic interruptions. Such Page 4

5 Lou Barrett Page 5 GPS tools also allow agencies to schedule work more flexibly since their use is less affected than traditional tools by time-of-day and weather. Process improvements driven by the use of AMG technology, from automated recordkeeping to coordination between design and construction personnel; create long-term cost efficiencies for agencies, contractors, and their customers. The technology also holds great promise for new applications (i.e., curb placement, pavement, trenching) that expand the potential return on investment in AMG tools, training, technical staff and data management. CONCLUSION As AMG is refined and utilized in more projects, AASHTO members and other governmental organizations (such as cities, and counties) benefit in lower bid pricing on construction projects where this emerging technology is used. Much of the construction industry is ready to use AMG and proactively support the technology as it results in substantial contractor cost savings. Page 5