ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1995.tb00293.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:The need to automate the process of erecting structural frames has long been recognized by the engineering profession, especially in construction of multistory structures in which members of similar sizes and floor panels of similar dimensions are to be erected repeatedly. Modern automated construction processes, when properly applied, have the potential of producing cost‐effective and higher‐quality structures as well as providing a safer environment for workers during construction. Since 1986, the Center for Advanced Technology for Large Structural Systems at Lehigh University has been working on the development of an integrated building system that has features particularly suited for construction automation. One of these features is the new types of structural connections that are easy to fabricate and lend themselves to multiple automated construction techniques. The second is a computer‐controlled, cable‐driven platform that can be attached to a crane. The combination of these technologies leads to a process that can effectively increase productivity, quality, and safety at the job site. This paper discusses these technologies as well as a preliminary economic assessment of the new

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1995.tb00294.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:Tunnels are formed with the aid of precast reinforced‐concrete segments. Erecting and positioning such segments using conventional erectors is tough and hazardous work. Labor‐saving automation has long been awaited. Our development of an automatic segment assembly robot that manipulates approximately 5‐ton weight segments to form a 9.5‐m‐diameter ring should help the situation. The robot has already found use in a 600‐m‐long tunnel construction site in Tokyo. High‐precision assembly is achieved thanks to a light‐section method that applies laser‐slit lighting and to digital servo technology. The benefit of automation tied in with a manual‐remote hybrid control system

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1995.tb00295.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:This paper describes the algorithms and detailed path‐planning methodologies developed to enable autonomous spreading and compaction processes in a waste landfilling operation. A given landfill site is spatially decomposed into cells using a recursive spatial decomposition technique. The cell size is determined using a probabilistic model for waste generation. Variation in the amount of waste generated on a given day is handled by a further spatial decomposition of a cell into monominoes. The recursive spatial decomposition processes of a landfill site into cells and each cell into monominoes are accomplished by employing a variant of quadtree data structure. A three‐dimensional path plan for an autonomous compactor that considers a variable working gradient in the range of 3:1 to 2:1 is generated for a pair of monominoes. Automatic location of the working place for a compactor is accomplished by a recursive traversal of the quadtree structure. The algorithms have been implemented using a computer‐graphic functional interface standard with C‐program

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1995.tb00296.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:A John Deere model 690 excavator, mounted on a Standard Manufacturing Company wheeled undercarriage, has been automated for the purpose of autonomously uncovering and removing unexploded buried ordnance. This paper describes the development effort, with emphasis placed on the autonomous navigation of the excavator system. Accurate navigation is required in order to properly position the excavator system so that it can uncover and remove the target buried munition. Autonomous navigation is accomplished by use of an A*search algorithm for path planning, an inertial navigation system (INS) integrated with a global positioning system (GPS) for vehicle positioning, and proportional control for path‐following. Data gathered from eight navigation test runs show that the excavator, on average, can navigate to within 0.67 m of a goal position and to within 0.021 rad of a goal orientatio

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1995.tb00297.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY

摘要:

Abstract:Robots have been investigated for automation of construction, maintenance, and inspection of civil works since the early 1980s. This paper describes the progress of robotics in civil engineering from the early 1980s to the mid‐1990s. It focuses on the environment and motivation for implementation of robotics, identifies key centers of development, identifies regional differences, and describes progress in key areas. It also traces the emergence and change of development strategies over time, it identifies practical achievements, and it identifies key developments for the future. It concludes that despite many false starts and setbacks, significant progress has been made, and significant changes are on the horizo

ISSN:1093-9687    

DOI:10.1111/j.1467-8667.1995.tb00298.x

出版商:Blackwell Publishing Ltd    

年代:1995

数据来源: WILEY