Dr. Sen Wang, associate professor in Robotics and Autonomous Systems (RAS) at Heriot-Watt University in Edinburgh and Lead on RAS theme at the National Robotarium, discusses how robots can facilitate 3D mapping on construction sites and what the industry can expect in the future robotics
The use of robots to assist humans in hazardous environments is growing, with autonomous systems increasingly being deployed to remove risk to human personnel as well as for commercial advantages such as speeding up the construction process, increasing efficiency and improving quality control. Now, robots fitted with Lidar are able to build up a 3D picture of their surroundings while spotting obstacles like rubble or machinery on construction sites. By assimilating the data collected, they are able to generate 3D maps of these sites.
Why use robots for 3D mapping?
3D mapping requires a device that can scan multiple points to represent a geometric structure as a 3D map. Today, the Lidar sensor is widely used in construction for 3D mapping as it is highly accurate and reliable. However, most of the Lidar-based survey solutions are static scanning, requiring personnel to manually move the Lidar sensors across sites, including in cramped and dangerous spaces. This can lead to complications not only for workers themselves but also for construction planners as they are obliged to wait for the scanning process to end before they can commence planning.
Using robots for 3D mapping is a way of overcoming these complications. By fitting Lidar sensors into their quadruped ‘SPOT’ robot, academics at the National Robotarium have developed a cutting-edge 3D mapping system that combines the precision of Lidar scanners with the efficiency and mobility of robots. Where Lidar scans take a few days to complete a 3D map of a construction site, robots can complete the task in just thirty minutes. Robots also have the ability to perform this task autonomously, saving the time of shifting the Lidar scanner across the site and reducing the inherent risks to personnel of being present on the site. Delivered through the ORCA Hub, a strategic project within the National Robotarium, the technique is now attracting interest from a range of construction companies.
What is the technology behind 3D mapping robots?
3D mobile scanning using robots relies on a technology that seemed unfeasible thirty years ago: simultaneous localisation and mapping, or SLAM. This means that robots can perform the dual task of 3D mapping and localising themselves in a new and complex environment, simultaneously.
SLAM technology can already be found in self-driving cars because it is essential that these vehicles gain an accurate and fast understanding of the environment they are in at the same time as they move through it. As such, the technological advancements underpinning 3D mapping robots have been key to solving some of automation’s biggest challenges.
Alongside collaborating with industry leaders to design construction-adapted tech, researchers at the National Robotarium also developed SLAM software that does not require a GPS signal while still allowing the robot to be located at all times. Consequently, robots can map areas such as underground tunnels and other remote and difficult-to-access spaces. This is important for construction mapping as all areas need to be mapped, regardless of location or accessibility.
In addition to SLAM, robots are being developed with autonomous navigation, or the ability to manoeuvre through a space without remote control. This technology is the fundamental enabler of 3D mapping as it entails that robots can navigate around any obstacle, including water, but also plan their path accordingly. Autonomous navigation therefore helps robots to adapt to their environment and optimise the routes around the sites, providing speedier and more accurate 3D mapping than static Lidar scanners.
Finally, advances in physical hardware have been key in the development of scanner robots. As construction sites are complicated and dangerous spaces, a robot that can navigate these terrains is necessary for the industry. Even common obstacles, such as stairs, require a highly developed and adapted technology. Physical hardware has been another key technological development to ensure that robots operating in construction sites are robust and reliable.
Where is this technology being used?
3D mapping robotics technology has been developed by researchers at the National Robotarium, a global leader in advancing research in Robotics and Artificial Intelligence. a research facility at Heriot-Watt University in Edinburgh. Roboticists have worked in collaboration with industry partners and construction professionals to ensure that the robots are equipped to operate optimally in the construction environment and that this technology is informed by the needs of the industry and solves the problems that construction businesses face.
Researchers are testing their 3D mapping robots regularly on the construction site of the new National Robotarium facility in Edinburgh. In this way they can monitor and understand each stage of the construction process more thoroughly and identify gaps within the technology, feeding this data and information back into the ongoing research and development. Several construction companies have expressed interest in the technology and the National Robotarium is keen to engage with industry to deliver solutions that add value to partners and meet the industry’s needs.
How will construction companies benefit from using robots?
Firstly, using robots for 3D mapping will allow construction companies to reduce their costs. Because the process of mapping is vastly accelerated by using robots, construction planners can compare progress of the build as it is taking place on site with the digital construction design, and identify and address discrepancies between the two at a much earlier stage. An estimated £2 billion is spent annually in the UK on construction rework, and earlier identification of discrepancies could significantly reduce this cost alongside reducing delays in construction projects.
Secondly, robots can help to increase the quality and efficiency of the construction process. Because the process of data collection is standardised through the use of robotics, the quality of the data can be more consistent across construction sites. This allows planners and engineers to trust the reliability and consistency of the information that informs their decision-making, and enhances the quality of the construction site infrastructure. With robots repeating the standards and the quality of work by following the same process in different terrains, the value of the data is improved and therefore the quality of the work increases. This frees workers up to focus on other tasks onsite.
Thirdly, robots can be used in construction to remove unnecessary health and safety risks. For example, using robots to access and inspect hazardous terrain like a tunnel reduces the risk for workers who may be unaware of obstacles or other dangers before entering the tunnel. Robots can survey the area and recognise obstacles that may pose a safety risk, thereby providing invaluable data for all members of the team that can be used in planning and risk assessment.
Finally, using robots for 3D mapping supports planners and site managers in overseeing multiple sites simultaneously. Because robots can be located remotely and provide data without human support, there is no need for managers to be physically present to access the 3D maps created. As a result, robots can be used in the context of remote working and can reduce the potential costs of extensive and sometimes international travel.
How will robots change construction?
In addition to having short term benefits such as lowering costs, de-risking sites and increasing efficiency of construction, robots have the potential to change the face of the construction industry.
As robots are increasingly used for automating specific tasks like drilling or digging, it is easy to envisage a future where the construction sector will be fully automated. This means that construction sites will run on a 24/7 basis and infrastructure will develop in complex and risky terrains. As such, robots can provide solutions to the challenges of the future, such as flooding or limited access to land, by optimising space and rendering construction more efficient and adapted to the space available.
As the National Robotarium continues to advance robotics and AI research on a global stage and work collaboratively with industry partners, many new and potential functionalities of robots in the construction industry continue to arise. Additionally, the continuous research and development that is taking place in the field of robotics is allowing researchers to explore ways that robots can be tailored to construction sites, thus building the future of the construction industry.
