Flying Robot Technology (Drone) Trends: A Review in the Building and Construction Industry

The fourth industrial revolution, also called Industry 4.0, has emerged with the development of information technologies and complex artificial intelligence systems. Industry 4.0 technologies have enabled a high level of production and contribute to social and environmental sustainability policies [1]. The fourth industrial revolution, which enables business models to go into production, supports production flexibility, efficiency, and productivity through various communication, telecommunication, and intelligence technologies [2]. Industry 4.0 technologies are integrated with sub-branches of technology, such as production, artificial intelligence, big data and analytics, blockchain, cloud, internet of things, cyber-physical systems, and simulation [3]. Sub-branches of technology provide the sustainability and improvement of existing industrial systems, potentially bringing competitive growth and innovations [4–8].

The growth of industry areas is part and subset of the universal growth process. Industrial investments of countries also reduce the amount of domestic expenditure, prevent foreign dependency, and ensure significant gains [9]. The transition of societies to the industrial revolution has been achieved with the combination of digitalization and smart production technologies [10]. The main feature of the fourth industrial revolution is the planning of the decision-making process in the management of a genetic algorithm, the classification and clustering of the data network, and the introduction of smart organizations in production [11]. With Industry 4.0, environmental awareness is increasing, and mass production and value creation systems are expanding. Energy consumption is increasing; accordingly, products are reconfigured, and cost adjustments are made [12]. With the development of advanced communication devices in human-machine interaction, an interaction occurs from the digital world to the real world. The use of smart sensors in the data processing process contributes to the development of prototypes and production technologies, affecting large-scale applications, synergy, integration, and development dynamics. Cloud systems and big data sets enable virtual representations to turn into real-time objects by testing simulation techniques and enable optimization and testing of different configurations during production by seeing physical changes [13].

Industry 4.0 technologies are divided into areas, such as Unmanned Aerial Vehicles (UAV), virtual reality and data management, cloud software, additive manufacturing (3D printing), advanced automation and robotic mechanisms, artificial intelligence, machine learning as can be seen in Fig. 1. With the evolution of mankind from the Anthropocene period, in which human beings have transformed the world with technological productions since the Industrial Revolution, to the age of hyperintelligence called Novacene, the developments in Industry 4.0 technologies are increasing and the way of life is changing [14]. At this point, it can be said that human power has been replaced by machine power. The potential of artificial intelligence is also emerging, as it offers rapid production, cost savings, and construction advantages in complex systems. With artificial intelligence systems that offer an unlimited dimension of production, the scale of the technology age is expanding through simulations, sensors and software.

Figure 1.

One of the main models of the development of the Industry 4.0 revolution is the science of robotics. With this revolution, applied science that has made progress in many sectors has emerged by paving the way for robot technology. The fact that robotics and unmanned aerial vehicles are seen as the smart systems of the future and allow work to be carried out without human intervention in dangerous missions have brought along technological innovations [16]. It is possible to come across robots in most areas of life. With the introduction of robots into our lives, which started with Industry 4.0, applications are carried out for various purposes and in different fields. Most of the robotic technologies applicable to construction applications today are demolition robots, bricklaying robots, welding robots, forklift robots, and road robots. Many future technologies can further improve the construction industry, including the basic principles of 4.0.

The tools used in robotic architecture can be grouped into 4 main headings as robotic arms, 3D printing robots, flying robots (drone), and customized robots (Fig. 2). Robotics is a key technology of Industry 4.0 that provides extensive fabrication in manufacturing. This technology has advanced automation systems and performs repetitive tasks precisely and at a lower cost. With the help of collaborative planning and advanced robot technology, it leads to the production of qualified products gradually in smart factories [17]. Unlike the first industrial revolution, the fourth industrial revolution focuses on mechanization, automation, and cyber-physical systems. A period was born in which human power was replaced by unmanned machines [18].

Figure 2.

A variant of robotics that consists of unmanned machines is drone technology. Drones, also called UAVs, are robots that do not carry human operators, fly autonomously, or host equipment and equipment with remote control systems [23]. A drone consists of a Global Positioning System (GPS), which allows remote control and receives real-time location information, and a control station (human, etc.), image acquisition and transmission mechanisms, and sensors to detect objects [24]. The GPS navigation system detects the location according to the satellite coordinates and detects the information of the movement of the drone and the road map [25]. The ability of drones to reach hard-to-reach areas, their flexibility, and maneuverability have led them to become one of the indispensable technologies with their economical and efficient monitoring, imaging, and real-time video creation capabilities in coverage over large-scale terrains [26].

UAV has an important position in the architecture, engineering, and construction (AEC) industry as it can reach restricted points for human access and provides advantages in terms of cost, safety, accuracy, and time compared to traditional methods [27]. Building Information Modeling (BIM) and digitalization are also making steady progress in the development of the construction industry [28]. With the rapid development of technology, countless technical opportunities arise for architects and engineers [29]. Unlike traditional methods, drones allow real-time telemetry data to be received during a flight. The connection of the UAV station with any smartphone device can also be provided [30]. The AEC industry for drones has become promising and attractive with the development and proliferation of work in this field [31]. The revolution in the AEC industry has been largely driven by BIM, cloud solutions, analytics, high-tech products, digitalization, and drones, which make up the whole of Industry 4.0 [9]. When we look at the historical development of flying robot technology from the past to the present in terms of the AEC industry in building production, it is seen that flying machines have been applied on construction sites since the 1950s (Table 1). In 1860, balloons were used to take pictures for remote sensing [32]. At the start of the First World War, aerial torpedoes, known as the origin of drones, were developed [33]. In recent years, research and examination of UAV vehicles worldwide have been growing by academic studies and industry companies [34]. Robots have been used for special construction tasks that conventional machines cannot do. Various other technologies have been developed, including ballistics, thanks to the helicopter, the most common air machine used in construction. Rockets and aircraft were produced. Each technology has brought its own advantages and disadvantages [35].

Robotic technologies all have the potential to improve many areas of the construction industry such as efficiency, quality, and safety; in addition, they encourage the creation of more business industries. The increasing development of industrial revolutions towards mechanization triggers the development of robotics science and the building and construction industry. Unmanned aerial vehicles are seen as indispensable products of the future. Drone technology has been popular in many fields in recent years and has begun to be used in different disciplines. Architecture has also started to benefit from these areas. In the study, drone technology, terminology, and its usage areas are emphasized, and research and examination are made on how and for what purpose it is used in the field of architecture. As a result of this research, inferences were made about the position of unmanned technology in digital fabrication and production.

Drone technology is a digital fabrication field that is used in many areas and is developing day by day. It has started to be used in the building and construction industry as it is among today’s trends and has become popular. Within the scope of the study, after giving general information about robotic technologies, specialization was focused on the applications of drones. After the areas with different drone applications were obtained through literature reviews, the studies in the building and construction industry were evaluated by making content analysis. Explaining the Industry 4.0 revolution and using robots, the historical development of flying robot technology in the field of AEC industry from past to present, explaining drone terminology and components, presenting the use and application areas of drone technology in a broad perspective and in the AEC industry, and the architectural studies that emerged as a result of digital fabrication with drone in the discipline of robotic architecture were examined. After the studies in the building and construction industry were classified, they were evaluated with the comparative analysis method. The aim of the study is to compile the works in the building and construction industry and to bring them together as a reference for future studies. Drone type, gripper, and software features in the studies were reviewed and inferences were made from the relationships between each other.

Without a pilot, drones are produced in varying variations depending on the degree of automation. Although it was considered dangerous and unsettling for people in its early years, it has become available on a wide scale in many areas today with the progress of control technologies and the decrease in cost [37]. Drones can be classified according to different parameters [38]. While there are drone types such as nano, micro, mini, small, medium, and large according to different weight ranges, they can also be categorized according to performance characteristics [39]. A wide range of drones is available, weighing less than 250 grams and weighing more than 150 kilograms [40]. Drones of different models according to their functions can be classified by looking at their configuration (Fig. 3). Wingspan, wing load capacity, range, maximum altitude, speed, engine types, durability, and production costs are important design parameters that distinguish different types of drones and provide classification. In Figure 3, HTOL is abbreviated as Horizontal Take-Off and Landing [38].

Figure 3.

Many drones are made up of modular parts in their body supported by an energy source. There are unmanned aerial vehicles with different body configurations depending on the flight style and mission. Body shapes, body materials, and different components make up the main mechanism of a drone [41]. Drone technology has a frame structure, propeller, motor, power system, electronic control, and communication system [42]. In addition, a camera or thermal infrared camera can be attached to record video during flight [43]. The time of stay of drones in the air is also an important feature. The condition of the drone’s stay in the air before recharging or refueling shows its durability. Depending on the task used, drones have a variety of hovering in the air between 1 hour and 36 hours. Fuel volume is also a component that is directly proportional to durability [44].

Looking at the physical structures of drones; multirotor means a multi-rotor unmanned aerial vehicle. As shown in Fig. 4, tricopter has three motors/propellers and three support arms, quadcopter has four motors/propellers and four support arms, hexacopter has six motors/propellers and six support arms, and octocopter has eight motors/propellers and eight support arms [45]. Configurations are generally described as “+” (the front of the UAV sees one of the support arms) or “x” (the front of the UAV sees between the two support arms). It is named H, V, and Y according to the shape of the unmanned aerial vehicle [46]. A typical drone consists of a quadcopter with four propellers, an engine, landing gear, battery and camera, and remote control. The camera is attached to a Gimbal with a stable and balanced holder feature. The battery contains a power management system and provides hours of flight time for a drone although flight time varies by battery type. The pilot of the drone can operate the flying robot in several different ways by viewing it directly in the line of sight, positioning it according to a trackable route on the screen, or creating a controlled flight path instruction with waypoints on a computerized system, and can return the drone to its original position when the flight is complete.

Figure 4.

Today, unmanned aerial vehicles are used in many operational situations. Depending on this, many factors such as control distance, stay in the air, and payload capacity of unmanned aerial vehicles play a role in the selection of flying robots. Although different unmanned aerial vehicles are needed in different disciplines, control methods can also vary. The capacity of the aircraft emerges according to the level of development. There are potential uses that vary depending on size and weight. When considered from micro-scale to macro scale, the level of development also changes depending on the software and hardware in it. According to the drone control modes, there are full manual, assisted manual, partially automatic, and fully automatic control systems [47].

In addition to classification according to control method and frame configuration, unmanned aerial vehicles are divided into four main categories as single-rotor, multi-rotor, fixed-wing, and fixed wing hybrid drones (Fig. 5). Single-rotor drones do not require complicated maintenance and repair as they consist of a simple structure. It can carry large loads over long distances by consuming less power. One of the most important disadvantages is that it needs constant air movement during flight, and it cannot stay stable in the air. For this reason, it does not perform well in functions such as monitoring and viewing [48]. Compared to single-rotor drones, multirotor drones are a type of drone with higher degrees of freedom, lower flying speed, stable flight capability, and are suitable for indoor use. The most common variant is the quadcopter, which consists of four rotors [49]. Fixed-wing drones are autonomously controlled by unmanned pilot. Although the average flight time is 2 hours, recently some designs fly up to 16 hours. Therefore, it is ideal for long-distance operations. Considering its limitations, it can be said that its cost is high, it requires skills for tasks and needs a launch pad to fly [50]. It has advantages in terms of speed, range, durability, and robustness [47]. Fixed-wing hybrid VTOL drones are a combination of the features of unmanned aerial vehicles. These drones, which can take off and land vertically, can stay in the air for a long time [51]. It has taken high flight time from fixed-wing robots and multi-rotor features from multi-rotor models [52].

Figure 5.

Drone technology is seen as a potentially important component for 5G and more advanced technologies, considering the sophistication of its cellular architecture in transmitting the wireless broadcast network from one point to multiple points. It can be observed that drones perform cellular network systems by communicating with each other in dense urban settlements, cities with high-rise buildings, transportation, and infrastructure [56]. With its reconfigurability feature, drones expand the network coverage and facilitate access to the user by reorganizing the network topology [57]. With the miniaturization of electronic parts in unmanned aerial vehicle technology, the use of lighter advanced materials, and the integration of increasing information processing units, a complex drone can be produced as in Fig. 6 [58].

Figure 6.

Drone technology offers significant benefits and opportunities across a wide range of disciplines [63]. In these disciplines, which are divided into civil and military applications, the durability, stability, and additional materials and equipment of unmanned aerial vehicles are important for use in complex areas. Historically, drones were first used for military activities such as reconnaissance and weapons delivery [44]. In the following processes, it has been carried out in civilian applications such as aerial photography, agriculture, remote control, and delivery (Fig. 7). Today, it is applied in wireless communication areas to create network coverage, and attempts are made to improve network connectivity in isolated areas [64]. With the COVID-19 pandemic, drone technology has been used to monitor civilian movements and social gatherings to reduce the risk of disease spread and lockdown violations [65].

Figure 7.

With the development of flying robot technologies, small-sized drone technology and software have also made progress. Drones, search and rescue, emergency and disaster management, monitoring systems [66], photogrammetry for 3D modeling [67], visual inspection of structures such as bridges, wind turbines, etc. [68], fire fighting [69], monitoring the weather, observing the energy infrastructure [70], urban planning and management [71], ecological monitoring and protection [72], archeology and cultural heritage [73], and logistics services [74] are involved in various applications such as wireless communication. In addition to these, flying robot technology is also used in categories such as agriculture, mining, and construction [75–76]. They are classified according to their intended use, depending on the missions for which they are defined. Apart from these areas, UAV missions are divided into 4 different groups according to NASA in Fig. 8 [77]. Drones can contribute to sustainable development and construction with ease of use to monitor energy projects such as pipelines, wind turbines and solar farms. Multirotor drones seem to reduce carbon dioxide emissions compared to other construction equipment, as they work with an electric motor instead of using fossil fuels. This shows that drones are environmentally friendly [75]. In addition, it contributes to sustainable development by saving time in construction sites, using them efficiently, using cost effectively and offering autonomous solutions in large-scale building inspections.

Figure 8.

4.6.

Applications in landscape architecture

Uncertain and complex nature of landscape areas is directly animated by the topographic imaging feature of unmanned aerial vehicles, leading to the development of new methods in this area. Up to 40 hectares of landscape area (based on current battery technology) can be analyzed with optical, infrared, or thermal data including parameters of vegetation, soil saturation, water quality, and Earth movement [89]. In Fig. 9, the usage areas of drones are viewed from a broad perspective.

Figure 9.

In addition to the historical value of ‘‘Rossum’s Universal Robots’’ (R.U.R.), the name of a science fiction theater play, the word ‘‘robot’’ was first heard here [90]. Research on robotic construction in architecture dates back to the early 1990s [91]. Despite the development of advanced technologies, access to these designs could not be achieved as a result of their inability to adapt to different design conditions and their inflexibility [92]. Today, drone technology can perform functions such as transport, flying, and imaging. Transport is one of the main functions of this technology. It can be used in every area with the transport function. It works integrated with flying action, carrying, and viewing. Imaging is used in many cases such as photographing structures, removing 3 dimensions, creating construction site stages, and conducting thermal analysis. Looking at the examples in architecture, it can be seen that the operations of transporting, flying, and imaging work synchronously. While digital fabrication is carried out in the architectural field, different types of drones are specialized by the development of algorithms and parameters in accordance with the construction techniques (Fig. 10). The adaptability and scalability of robotic fabrication depend on integrated design, construction, mechanism, and control systems [93]. Different applications have been made with the addition of software and additional hardware and sensors. This section shows through examples, how and for what purpose the three features of drone technology in architecture are used.

Figure 10.

Recent advances in robotic sensing, computing, and control systems have led to the development of new technology trends by enabling the customization of traditional computer-aided manufacturing tools and mechanical devices. New autonomous devices can adapt to the environment more easily than previous-generation technologies and reflect a taught situation in their behaviour [95]. From this point of view, more agile, sensitive, and responsive robotic vehicles have been produced day by day compared to previous generations. Unmanned aerial vehicles, a branch of robotic vehicles, also offer a new approach to architecture [96]. Today, architectural design and manufacturing are progressing in cooperation with robotic systems. The construction of architectural structures and the production of building components have also become dependent on robotic mechanisms [35]. In the study, digital fabrication in architecture is discussed, and the production techniques of the studies that are handled chronologically are presented (Fig. 11).

Figure 11.

5.1.

Construction of Cubic Structures with Quadrotor Teams

Robots are a growing class of applications used in the construction and assembly of structures [97]. In this study, the assembly of structures in three dimensions is discussed. The work has been shaped in parallel with the work done by the autonomous robots used in the construction of scaffolds, tower cranes, and skyscrapers. Assembly principles have been applied following basic design principles. The study aims to measure the ability of the aircraft to detect, transport, and assemble on-site according to the given command. Quadrotors were chosen as unmanned aerial vehicles, and studies involving more than one quadrotor were carried out. The quadrotor has an approximate diameter of 55 centimeters and a total weight of 500 grams including the battery. The maximum load-carrying capacity of this drone, which can stay in the air for approximately 20 minutes, is 500 grams. A simple cubic structural plan was created. In this cubic structure, each edge piece is obtained from a rectangular prism. In the process of forming a cube with these parts, which are considered columns and beams, a special mechanism has been developed for quadrotors to carry rectangular prism parts. The steps for constructing the quadrotors with algorithms are defined. Magnets are used to integrate the rectangular parts into the structure to ensure that the connection points are strong. Rectangular part modules weigh between 119-179 grams [98]. Cubic structures and constructions such as pyramids, walls, towers, and castles have been tested through simulations and experiments (Fig. 12).

Figure 12.

5.2.

The Flight Assembled Architecture Installation

The tower structure, consisting of 1500 polyurethane foam modules with a height of 6 meters, a length of 30 centimeters each, and a weight of 90 grams, was obtained as a result of 18 hours of work with 4 quadrocopters and continued for four days in the Fonds Régional d’Art Contemporain (Regional Contemporary Art Fund) exhibition in France [100]. This study highlights the strong, robust, and reliable aspect of drone and human interaction [101]. The control mechanism of the quadrocopter came to the fore with the trial of the study [102]. In the tower where more than one quadrocopter was used simultaneously, navigation, hardware, software, and control systems were developed to prevent the modular elements from colliding with each drone. The layout of the tower was also pre-calculated. With this study, new computational methodologies, dynamic construction technology, and new materials that can be used in the construction process of drones have been created [103]. During construction, quadrocopters held the modules from the center and transported them to the settlement (Fig. 13). For the construction process to continue actively, the charging stations of the drones were built at a height of 4 meters from the ground [100].

Figure 13.

5.3.

Architectural fabrication of tensile structures with flying machines

Research demonstrates the constructability of lightweight tensile structures with quadrocopters. Structural elements such as ropes, cables, and wires are subjected to tensile forces in building types. The study also includes the digital fabrication of basic elements such as links and nodes used in the construction of tensile structures by transferring them to quadrocopters. A basic construction system was determined with quadrocopters, and prototype tension structures were applied. With the attachment of the rope mechanism to the drone, structures within a certain trajectory were obtained with the hybrid power-position control strategy (Fig. 14). With this study, it has been proven that the construction system can be created by reaching the points that cannot be reached with traditional construction systems with drones [104]. Tensile structures are preferred because they have high structural strength and can be used in large spans. After the knot and connection analysis of the ropes in various configurations, they were introduced to the quadrocopters with experiments, and the construction process was completed [91].

Figure 14.

5.4.

Aerial construction of space frame structures

Unmanned aerial vehicles are a new form of dynamic construction methods. They have the ability to digitally supervise and control designs, where more radical operations can be performed than gravity-dependent robots [103]. Space frame structures can also be produced depending on the degrees of freedom. In the study, the quadrotor was chosen as the drone type. With the help of the gripper integrated into the quadrotor, the rod elements are transported in the specified orbit and fixed in their places (Fig. 15). In the prototype work, fluid and air pressure sensitive styrofoam balls were used to reduce the weight of the gripper. Conceptually, carbon rod elements of different lengths at various angles were taken with the gripper and connected to form a space frame structure. The rod elements are 14 millimeters in diameter and have lengths ranging from 80 to 120 centimeters. By making simultaneous use of two quadrotors, one held the rod element with the gripper, while the other served as a support during the assembly phase [35].

Figure 15.

5.5.

Building a Bridge with Flying Robots

In the study, it is aimed to create a structured system by drawing maneuvers around the columns with 3 and 4 millimeters of ultra-high molecular weight polyethylene rope (Dyneema) attached to the unmanned aerial vehicle [35]. Evaluations were made using simulation programs before digital fabrication [105]. The nodes created with ropes provided fasteners, allowing a structure to be built at the initial level. Within a 10x10x10 meter indoor area, a space was created that was surrounded by cushions on 3 sides, and measures were taken against collisions and falls. Mathematically, the binding technique of the ropes was calculated and transferred to the quadrocopter. Tension bridge formation was performed between the support elements and two vertical columns. The experiments were repeated by keeping the turns of the quadrocopter and the tension of the rope variable. Surfaces were obtained by drawing zigzags with drones (Fig. 16). First, a zigzag process was performed with a single drone, then this process was repeated with two drones. To create the bridge structure, the three-dimensional construction capability of the unmanned aerial vehicle was utilized. Span bridge design which was 7.4-meter was made in 3 stages. In the first stage, linear connections were made, and the foundation was formed. In the second stage, 3D network connections were created. Finally, a person weighing 80 kg climbed on top of the structure and tested the structure [35].

Figure 16.

5.6.

Multi-Machine Fabrication, The ICD/ITKE Research Pavilion

Integrated design and computational methods for potentially low-cost fiber composite structures without waste, surface molding and labor, simulation, with research at the Institute for Computational Design (ICD) and Institute for Building Structures and Structural Design (ITKE) at the University of Stuttgart, and fabrication processes were developed [106]. The study investigated the digital fabrication of unmanned aerial vehicles operating synchronously with two robotic arms in architectural systems. Quadrotors were used for material transportation and location determination operations between industrial robots [107]. The study aims to understand the applicability of six-axis robots in the construction of lightweight, material-efficient, and wide-span fiber composite structures by supporting the limited work environment with drones. The reason for choosing unmanned aerial vehicles is to find alternative solutions in the building production process, benefit from high maneuverability, and show their usability in unlimited working areas. Cantilever structure which was 12-meter-long and 2.6-meter-wide was built with mesh systems. Quadrotor, tension mechanism, magnet, and grippers took part in the repetitive operations between the robots (Fig. 17). The built cantilever structure weighs approximately 1000 kilograms and covers an area of 26.5 square meters [108].

Figure 17.

5.7.

Cyber Physical Macro Material as a UAV [re]Configurable Architectural System

The research presents a new strategy in reconfigurable architecture in unmanned aerial vehicles and cyber-physical macro material combination according to autonomous reorganization and behavioral design technique rather than singularly robotic assembly and construction method. The scope of the work is to obtain a self-supporting 2.5-meter high roof canopy (canopy element) in the form of a polyhedron, made of lightweight material, consisting of carbon fiber units in the combination of robotic processing and communication (Fig. 18). Three different behavior scenarios were applied as adaptive behavior, interactive behavior, and learning behavior in user cooperation with software, control system, programming, and hardware. After being produced from carbon frames in a modular way, the elements taken by the unmanned aerial vehicle were carried into place with the help of a gripper with magnets and complete the canopy. Specialized hexacopter design was made, different from standard drone types. The localization and control system, autonomous navigation, and Robot Operating System (ROS) software were developed, and digital fabrication was carried out at the architectural scale [109].

Figure 18.

Smart digital materials, which were completed with the integration of digital fabrication method with robotic tools, can be designed under the name of cyber-physical architecture through networked embedded systems, Internet of Things (IoT), data and services, providing high adaptability and benefits in temporary situations. After the investigated examples, they are classified according to the application, drone type, gripper, and software parameters chronologically according to the years and are shown in Table 2.

Table 2.

Categorization of the studies by looking at the building production characteristics (by the authors)

Application	Drone type	Gripper	Software	References
Project 1Constructing cubic structures such as pyramids, walls, towers, and castles with rod elements		A single degree of freedom gripper made of acrylic actuated by a servo motor with a layer of foam to facilitate grasping	Special Cubic Structures construction algorithm and Wavefront Raster (WFR) Algorithm, VICON motion tracking system, and Robot Operating System (ROS)-MATLAB bridge	[94], [98], [99], [110], [111]
Project 2Prototype of a high-rise building based on the principles of balance and stabilization of 1500 polystyrene brick elements		Ingressive grippers. The gripper consists of three metal pins, each actuated by a single servo. The servos and pins are mounted to a three-dimensional, printed rigid gripper base, arranged in a circle with 120° of separation	A network of intercommunicating computer programs using Python, Rhino, a real-time camera system, and a motion capture system	[94], [100], [103], [112]
Project 3Creation of tensile structures in the architectural construction production process with the help of durable ropes		A passive roller to deploy the Dyneema rope	Force control system, an algorithm (specified by heading, position, velocity, and acceleration), and motion capture system	[91], [104], [113], [114]
Project 4Realization of structure production based on the basic principles of space frame structures with rod elements		Styrofoam balls (granular filling material contained in a balloon membrane)	Force control system and ROS	[35], [103]
Project 5Making a bridge design with polyethylene ropes according to the knots and connection points of the ropes		Custom 3–4 mm Dyneema rope dispensers mounted in the centre	Rhinoceros 3D - Grasshopper, computational simulation techniques (physics engines), Autodesk Maya, Parallel Tracking and Mapping (PTAM), and ROS	[35], [105], [115], [116]
Project 6Creation of cantilever structure with fiber composite fabric material between two robotic arms with drone		Hydraulic gripper for gripping the winding effector of carbon fibre-reinforced composite material	ROS and a custom-developed web interface	[107], [108], [117], [118]
Project 7Obtaining a roof canopy by combining modular carbon fiber framed units with a polyhedron shape		The gripper, the locomotion body, and the localization system are attached to each other via dampening springs. The gripper uses hooks to attach to each unit	PID control (proportional-integral-derivative control) system, ROS, and a set of Web Applications over WebSocket protocol	[109], [119], [120]

Innovative construction techniques are used in contemporary buildings [121]. Drone systems also come to the fore in this context. Looking at the samples examined, it is seen that the most used drone type is the quadcopter. For this reason, it can be said that the type of quadcopter is common in the building and construction industry. When classified as gripper, it has been observed that each digital fabrication sample uses different grippers depending on the method and material to which it is applied. The weight of the material to be transported is also important in the selection of the gripper. While the gripper type used for the transportation and placement of heavy materials is attached to the drone with durable and robust apparatus, light gripper types are chosen for light material applications. In terms of software, it is seen that software containing detailed analysis is used in complex construction techniques. With the use of advanced software, drones can have more hardware and can do multiple tasks at the same time. It is noticeable that most of the examples use ROS software. The integration of different software in addition to the drones’ own software paves the way for the transition from small-scale applications to large-scale construction works. With the addition of visual simulation tools, drone technology becomes equipped. Drone studies can perform the monitoring and imaging function at a significant level in the building and construction industry. However, it remained at the experimental level in terms of building. It is foreseen that large-scale structures can be built as a result of the development of software and hardware of drones and their integration with macro-robotic arms. There are many examples of robotics science in the building and construction sector, but robotic examples using drones are limited. In this study, it was aimed to draw attention to the uses of drones in the building and construction industry and to create the basis for their larger-scale use in future studies.

Unmanned aerial vehicles are an important part of the developing technology world today. Technological areas such as mechanization and virtual environment attract people’s attention, and innovations come with this curiosity. Drone technology is also a system that attracts people’s attention and can be used individually because it is easy to access today. Three major developments have been seen in drone technology: miniaturization, autonomy, and collective use. Miniaturization is one of the most developed areas from the past to the present. Like most robotic vehicles in their field, each new generation of drones is getting smaller, lighter, and cheaper than the previous generation. Better returns are obtained with new materials developed and more efficient batteries. Measures such as flight range, maximum altitude, and maximum payload are also improving day by day. The second improvement is the increased autonomy of drones. Most commercially available drones are remotely controlled but often require flight stabilization software for autonomy. For this reason, professional unmanned aerial vehicles are programmed before the flight. Today, determining more autonomous flight routes, perceiving environmental conditions, taking precautions to adapt to change, and performing defensive reactions when under attack have made drones indispensable. The third development is the use of drones by sharing work. Increasing the autonomy of drones enables cooperation between drones in use together. With this use, more than one unmanned aerial vehicle can share loads with several drones when heavy loads exceed the load of one drone. With these features, the use of drones has expanded.

Architecture is one of the disciplines where drones are developing. The industrial revolution, which started with transportation and imaging in this field, has recently been brought to the production of architectural structures. Drones, previously used in the building industry for thermal analysis, facade cleaning, and review of building construction stages, have moved from prototype scale to building size by integrating different apparatus with the increase of technological data. The digital fabrication process, which first started with a single drone, has expanded and become more complex with sharing the work with multiple drones. The development of complex systems by prioritizing the features of drones such as the battery, flight time, sensors, and software has been effective in the progress of digital fabrication. A collaborative workspace was created by harmonizing the architectural programs with the software systems of the unmanned aerial vehicles. In this context, business areas have expanded, and different studies have begun to be carried out with the combination of systems. With this study, it is thought that in light of the industrial revolution, digital fabrication, and innovations in software systems, drones will play an active role in architectural production in future studies. With drone technology, studies are carried out to shorten the construction period, reduce the cost and the workforce. Based on the samples examined, it is seen that the efficiency of drone technology in the building and construction industry has increased. The use of more than one drone, rather than a single drone, will also pave the way for large-scale construction projects. Advances in drone type, gripper and software features will bring complex systems along. This technology, in which different configurations are added day by day, will continue to grow with the contribution of architecture.