PERFORMANCE EVALUATION OF THE UT AUTOMATED ROAD MAINTENANCE MACHINE
This final report mainly focuses on evaluating the overall performance of the University of Texas' (UT's) Automated Road Maintenance Machine (ARMM). First, the ARMM's man-machine-balanced control loop was further developed then rigorously tested and evaluated based on (1) accuracy, (2) time, and (3) quality of the resultant seal. For the efficiency evaluation, thirty pavement crack images, which included longitudinal, transverse, and block cracking, were collected from a UT research campus, and field trials were completed at five locations (Austin, San Antonio, Dallas, Corpus Christi, and Travis County) in the state of Texas. Several additional significant improvements were made to the ARMM during the course of this project. Second, the ARMM's productivity was estimated based on (1) the results of the efficiency evaluation of the man-machine control loop, (2) observations made during the series of field trials, and (3) a productivity model. The mathematical model that predicts the productivity of the ARMM under various work conditions was developed as a means for job estimating and for rating the performance of the ARMM. The ARMM's estimated productivity was then compared with the typical productivity rate associated with conventional crack sealing methods. Evaluation results from the field trials and implementation recommendations are also made in this final project report. It was concluded that the introduction of automated methods to the pavement crack-sealing process will improve productivity and quality and can reduce costs and safety risks. The latter is a direct result of reducing normal crew sizes of seven to eight workers to only three to four workers. The reduction in crew size and the increase in productivity of the sealing process translate directly into significant potential cost savings. By automatically recording work completed, the ARMM should help improve project controls; by its ability to work at night, the ARMM should reduce road user costs.
Evolution of an automated crack sealer: a study in construction technology development
Demographic, regulatory and competitive forces impose increasing pressures on the construction industry. Automated pavement crack sealing is a typical example of the technology developments that are emerging in response to these industry pressures. Development of automated construction technology such as the crack sealer involves several issues including the design cycle, economic feasibility analysis, financing, and implementation. An examination of these issues, using the development of the crack sealer as a case study, leads to the conclusion that revolutionary construction technology developments are feasible and that in the United States (US) they will be financed and carried out in the form of a variety of industry, government, and academic consortia.
A MODEL FOR EVALUATING AUTOMATION IN ROAD MAINTENANCE
Automated road and highway maintenance has extremely high potential because of its many benefits, including direct and indirect cost savings (economic factors); improvements in safety, quality, working environment, and productivity (qualitative factors); and reduction in emissions and fuel/oil consumption due to the expedited maintenance operations (environmental & energy factors). A comprehensive Automated Road Maintenance Evaluation (ARME) model was developed through which the benefits of all these factors can be evaluated by a system's approach. Using the analysis tools of the model, the automation feasibility of the major maintenance activities was evaluated using the ARME model's needs assessment phase tools, and the feasibility of an Automated Crack Sealer (ACS) system was evaluated using the ARME model's technology evaluation phase tools. Of the 25 maintenance activities evaluated, only 13 were found out to be feasible for automation. Most of these activities (7 out of the 13) are pavement related, four are roadside maintenance activities, and two are traffic related. In evaluating the feasibility of the automated crack sealer, estimated maintenance cost savings, user-cost savings, reduction in emissions/energy consumption, and the improvements in the qualitative factors were determined. Several scenarios, from both the Texas Department of Transportation and private contractors' perspectives, were analyzed; and in every scenario the system proved to be very feasible for all the analysis factors (economic, qualitative, environmental & energy).