Automation and robotic applications for use in the North American construction industry are currently under development at numerous university and industry laboratories. A number of these applications have been tested under simulated or actual jobsite conditions; some have provided enough information to determine technical success or economic feasibility of the technology. Further development of robotics applications for the construction industry will be achieved by a combination of university research and development and jobsite experimentation in the private and government sectors.
EARTHWORK APPLICATIONSExamples of automation and robotic applications on North American jobsites include automated precision guidance systems for construction machinery and remote-controlled devices to inspect or rehabilitate structures. Automated excavation grade control using laser surveying equipment combined with electro-hydraulic feedback control systems mounted on bulldozers, motor graders, scrapers, etc. has been used for civil earthwork applications. In highway grading, large parking lots, and canals , these techniques have reduced costs in some cases by over 80 percent and improved quality (e.g., subgrade thickness tolerances of 2 percent versus 10-20 percent). These methods substitute lower-cost machines (e.g., small bulldozers for motor graders) and lower-skilled operators, while improving quality. 11,2] Another earthwork application is the John Deere 690C Teleoperated Remote Controlled Excavator. Fully operable from remote locations, this machine is designed for excavating and handling unexploded ordnance and other hazardous materials such as chemical and nuclear waste. It is equipped with a high-resolution color video monitor with pinch diagonal screen, speakers, and amplifiers. The camera controls include pan, tilt, zoom, focus, and iris. The excavator has been used successfully at a munitions disposal site in Tennessee and is being evaluated for rapid runway repair functions.t13jOther civil earthwork applications include Miller Formless Co.'s Automated Slipforming Systems and Bulk Cement Unloading Systems.[4] Miller Formless has developed five machines for sidewalk curb and gutter construction that can pour concrete closer to obstacles than other forming equipment. They can be assembled to order for the construction of bridge parapet walls, monolithic sidewalks, curbs and gutters, barrier walls, and other continuously formed elements commonly used in road construction. The machines include proportional control of the grade system by two grade sensors; two amplifiers; two servo valves; and a cross-sloping feature. All of these machines can operate in a 16 playback mode, following a preset path of work. These devices require less labor than conventional methods and are considered economically feasible.[5'Robot Excavator (REX), created by Carnegie-Mellon University (CMU), is another automated earthwork application. REX unearths buried utility piping by sonar-mapping an excavation site, planning the digging operat...