This paper investigates two belt mechanics theories and discusses the situations and materials for which they apply. Traditional creep theory is presented along with shear theory which was recently introduced to describe the behavior of steel-reinforced belts. Emphasis is placed on determination of tensions in the spans of a running belt and on applying results to multipulley configurations.

Surface finishing of large storage tanks represents a typical area in which construction automation techniques can yield significant improvements over conventional methods. Current techniques are costly and laborious, and they expose workers to significant health and safety risks. Automation offers potential improvements in each of these areas and is well suited to the large, uniform surfaces of the tank wall. The University of Texas has developed a prototype automated surface finishing system for use on large diameter tanks. This system uses a computer-controlled motion module to refinish the vertical exterior walls of a tank. The module is configurable for both blasting and painting and utilizes conventional surface finishing equipment for these processes. The University of Texas' automated paint sprayer was field tested in January, 1992 at an Amoco pipeline facility in Alvin, Texas. These tests, which were used to demonstrate automation techniques to members of the construction community, are described in this paper. The successes of the system are reported along with the problems, and recommendations are given for improving the system. An economic analysis is presented along with future plans for the system.

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The robotic high-rise building maintenance system is an automated system of performing maintenance works on the outer walls of high-rise buildings, including cleaning, coating, and inspection. This study, a robotic high-rise building maintenance system is proposed that overcomes the conventional limitations and introduces an algorithm for contamination measurement that uses an optical (IR) sensor; quantitative contamination evaluation based on the algorithm; and a strategy for the maintenance of the outer walls of high-rise buildings.

Fundamental advances in sensors, actuators, and control systems technology are creating opportunities to improve the performance of traditional construction equipment. New capabilities are being developed as well. These improvements in performance and new capabilities are resulting in better safety and efficiency. However, selecting control strategies can be confusing, and measuring and predicting their performance can be difficult. This paper identifies emerging control paradigms and describes methods for measuring their performance. Many control paradigms and corresponding example applications are identified, including single degree of freedom control sticks, multiple degree of freedom joysticks, operating and safety constraints, teach/learn capability, resolved motion with internal and external sensors, spatially correspondent controllers, tele-operation, graphical programming and control, and autonomous control. Methods described for measuring performance are based on American National Standard Institute (ANSI) standard tests, applications analysis, and ergonomics. Examples focus on the University of Texas at Austin's large scale hydraulic manipulator and automated pavement crack sealer with the results of performance tests on these manipulators being presented.