Experts predict that soon remote-controlled and automatic machinery will take the place of the conventional construction machinery (Chamberlain 46). Today, robots are used where it is difficult or impossible to use heavy machinery, mainly as a replacement for manual labor. In practice, a single operator with a remote control is cheaper and more productive than a team of workers. The use of the robotics in construction allows abandoning the purchase of surplus equipment. Robots are capable of climbing walls, performing finishing work, building modular constructions and frames of buildings, and replacing masons and welders. In recent years, automation has been successfully implemented in the construction industry and the remaining humans only monitor the correct operation of special devices. This paper is focused on observing the essence of robotics in construction and its benefits over the conventional construction machinery.
Overview of Robotics
Robotics is a high-tech, knowledge-based engineering industry that is developing intensively in all advanced countries. Robotics systems are now widely used in construction, transport, medicine, military, aerospace, and other fields (Jeong et al. 347). Despite the widespread use of robots in modern society, a universally accepted definition of the term “robot” does not exist. However, many scholars define a robot as an automatic device designed on the principles of a living organism. The robot independently carries out activities according to the program concerning different operations typically performed by a person. Robots usually have a link to an operator.
The variety of robots is so great that there exists a problem of their classification. Typically, robots are classified according to the following criteria: (a) the area of use (industrial, military, research, medical, etc.); (b) the area of operation (ground, underground, surface, underwater, air, space, etc.); (c) the degree of mobility (fixed and mobile); (d) the type of the system control (software, adaptive, and intelligent); and (e) the functional purpose (transport, information, and combined) (Annetta and Minogue 34). Building is a part of social activity, which includes work on the design of objects, their construction, installation, and resources for their repair. The process of construction of buildings is very complex and it has its own specific features, such as the immobility of objects, the duration of the production cycle, the need for appropriate material base, and high dependency of the construction process on external factors, such as weather, organizational and technical inconsistencies, and changes in the external conditions of production.
The construction process requires a great deal of work, sometimes unbearable for humans. Therefore, in recent years, scientists are becoming increasingly interested in the automation of construction processes. The combination of scale and the desire to improve efficiency generate an enormous potential for technological innovations in order to increase productivity. Scientists have already created machines that can climb walls, perform finishing work, pour the foundation, and build frames of future buildings. Robotics is carried on remote-controlled electric cars on tracks with a strong arm and a variety of attachments. Basically, these machines are used for construction and demolition work, clearing areas for development, and hazardous work. Special robots and automation processes can increase productivity and minimize occupational injuries (Fukui et al. 2).
Modern construction robots can automatically build a three-story building in a shorter time and at a lower cost price than by using conventional work practices. Compared with traditional methods, robots will provide a two hundred fold gain in speed and a five-time reduction in the cost of construction (Chamberlain 87). The diversity of construction projects and their complexity are increasing every day. At the same time, customers are placing ever more stringent requirements for the timing and quality of construction works. To improve the efficiency of operations and to successfully compete in today’s environment, companies need to change the building methods of the construction business according to international practices and technologies. To do this, construction companies use robotic technology to accelerate the construction of buildings, improve the quality of the operations, and reduce labor costs.
The Use of Robots
The special equipment of building robots consists of small and light parts that can fit easily in any vehicle. Robots are highly maneuverable, can be equipped with attachments, and have no exhaust fumes. The operator can work with them in any conditions without safety violations: in the narrow tunnels, basements, on the edge of high-rise structures, near dilapidated floors, reconstructed bridges and viaducts, etc. (Jeong et al. 348). Many studies reveal that the advantages of building robots can be attributed to the fact that the absence of noise allows to use them at night in the immediate vicinity of residential houses (Annetta and Minogue 34). Moreover, their use eliminates the discomfort from noise, even during the renovation of premises within existing facilities. Robotics may be controlled by a single trained operator, who is located at a safe distance.
Robots are used in confined spaces and indoors, underground and in high-rise construction, for dismantling and reconstruction work on the pile and the zero cycle. According to Lee (119), current models of robots can perform the following tasks: loading, demolition of concrete and masonry structures, dismantling of metal, removal of surface layers, drilling holes, transfer items, and others. Some models have the armor, thermal, and radiological protection that allows to use them in hazardous and corrosive environments.
Robots may be used for civil works that complete all main tasks in the construction, such as the land, installation, concrete, etc. These activities are generally characterized by high complexity and monotony that is particularly difficult for the workers. However, to make a profit the owners aim to perform the task in the shortest possible time without any loss in quality. Such tasks as the demolition of buildings, their subversion, cleaning of debris are readily available for automation. Moreover, people do not have to work in dangerous areas, which reduces the number of injuries to a minimum.
Furthermore, robots are also used for excavation work which is one of the most difficult construction tasks. It cannot be done without special equipment. Robots in this area are conventional excavators that can be managed without human intervention. Such robots as, for example, DRX 250 can be used for various purposes, as they have the ability to quick-change (Jeong et al. 349). Besides excavation and dismantling, the device breaks the refractory materials, concrete and metal structures, rake debris, as well as conducts loading and rescue work. When using this technique, tools with which the machine is equipped are very important. Another useful device is robotic crane manipulators. They are hydraulic crane systems with the capacity of up to 6 tons (Chamberlain 89). Typically, devices are placed on the chassis on the board of Lorries and they are operated by remote control.
Drilling robots are very helpful in the construction process during boring and piling work. For example, a self-propelled drilling rig IVECO-ASTRA is intended to create wells of different types and diameters (Fukui et al. 9). A multi-purpose robot WIRTH HOWDEN allows customizing the machine to optimize drilling in a certain way, the choice of which depends on the purpose and environmental conditions (Annetta and Minogue 36). It is also used to force the concrete piles, pipes, and sheet piles of different types and sections.
Artificial Intelligence Strengthens Positions
Often, robotics is comparable in size to a mini-technology and performance to a 20-ton excavator. For example, the robot Brokk 400, developed by a Swedish company, can pass through doorways that are 0.8 meters wide and 1.4 meters tall up any number of flights of stairs in buildings, basements. It can work on industrial premises, pile fields, in business centers, and residential homes (Lee 123). Robots are often designed for medium-operations work indoors, as well as for use in a highly sensitive environment. Recently, sophisticated machines began to appear created for performing specific work. For example, some construction robots are now capable of moving on vertical walls made of any material. The effect of coupling various bodies under the action of a system of external electrostatic field allows the robot to move on vertical surfaces (Chamberlain 95).
Today, robots can build a base of low-rise buildings on monolithic technology. The research asserts that houses built with their application can have a total area of 150-1500 m2 (Jeong et al. 350). Working around the clock, a robot can not only automate the work previously considered to be primarily manual, but also completely abandon certain types of work, resulting in a reduction of construction time by up to two months. At the construction site, a robot itself makes excavations for the foundation, prepares the concrete solution, organizes the supply of the solution to the site, etc. The only function of workers is to ensure uninterrupted supply of components for the concrete mix and control the equipment. Mounting and dismantling the installation of scaffolding and formwork are not needed.
It turns out that a team of two people using robots can erect buildings of 5 boxes in a year. Those houses will be ready for finishing and communication work. The use of a computer and sensors ensures accurate construction of walls, ceilings, snap-in horizontal and vertical planes with a deviation of less than ± 0.4 mm from the project (Lee 125). Computer design of the house is the basis for the robot control program. Researchers believe that sooner or later it will be possible to engage robots in interior decoration, in particular the application of the plaster and wallpaper made from special materials (Annetta and Minogue 38). However, the terms of practical application of automated construction machines are not yet known, but serious work in this direction is conducted constantly. Different types of finishing work are considered the most labor-intensive. The average output plasterer in manual labor time per shift is extremely low. Robotics in construction can solve this problem, reducing the heavy and unproductive manual work of plasterers.
Despite a number of experiments in the field of construction, the experience of practical application of robots in the construction sector is not widely accepted. First, robotics construction is constrained by the fact that each project is unique and requires the use of standard and high-tech solutions. Secondly, the use of robots is associated with the need for expensive building technologies; otherwise, the effectiveness of the use of sophisticated technology will be lost. Third, the value of robots is prohibitive, ranging from 1.5 to 2 million dollars (Jeong et al. 350).
The Advantages of Robots over the Conventional Construction Machinery
One of the important advantages of robots is that they can work where people are not able to. Robots in construction are not similar to the existing technologies, and their main task is to work on a large scale. Robotics possesses intelligence that is relevant to the human brain. Robotic technology for each type of construction works includes manipulators, effectors, control devices, and a variety of automated transport vehicles. These mechanisms can replace a builder in the performance of hard, monotonous work, and significantly speed up the construction process. While the conventional construction machinery cannot replace individuals in the construction sites, robots can do it rather effectively. Therefore, machinery that is operated by a person maintains support for itself, not for the humans, while robotics protects people from danger and injuries. A well thought-out management system with remote control increases productivity.
Transportation and logistics are very important in the field of construction. They are used to deliver materials from the warehouse to the specified location of construction. In this case, the use of automated machines will help reduce labor costs. Robotics in construction provides high productivity and good quality work in the conduct of assembly tasks. Admittedly, it can be achieved with the use of modern equipment for complex mechanization. Robotic assembly and handling devices, such as a universal system of KUB-2.5, automatically carry slab joints, joints of multi-storey towers, units, and connection panels (Fukui et al. 12).
It is hard to imagine the construction site without loading and unloading that is now fully mechanized. For this purpose builders use the machinery of general and special purposes. Autonomous cargo handling cranes are used for working with concrete and metal structures, equipment, and materials and transported in bags, containers, and wagons. Mobile cranes are equipped with special gripping devices, clips, and buckets. Robotic loaders perform a significant amount of loading and unloading due to their high mobility and versatility.
The scientific and technological progress in the field of construction has rapidly developed and brought obvious results. Robots and automated machines are actively used at construction sites, relieving people from the labor-intensive operations. Construction companies use robotics to increase profitability, and they perform many important tasks in the shortest possible time without any loss in quality. These activities are usually characterized by high complexity and monotony that is extremely difficult for the workers. Moreover, people do not have to work in dangerous areas, which reduces injuries.
Therefore, robotics in construction has many benefits over conventional construction machinery.