b'Continued from page 23How drones are poised to help the build cities of tomorrowvideo demonstrating a fleet of robots flying in tight, centimeter-perfectIn Europe, a consortium of robotics professors from across the formations, requiring them to calculate control commands 100 times percontinent have come together to put this thinking into action. The Aerial second to avoid crashing into one another. Banding together to form neatRobotics Cooperative Assembly System (ARCAS) project is aimed at squares, rolling figure eights and various other patterns, the choreographytaking cooperative robot flight and using it to build real world structures. on show certainly made for an impressive spectacle, but held more valueFirst though, it must establish solid scientific grounding for real world than was reflected by the wows in the audience. As explained by Kumar,deployment of a flying robot workforce, and like other research efforts, is with an ability to fly in effect as one solid shape, it follows that the strengthcreating and solving new problems as it goes through the process.and carrying capacity of the drones multiplies. By using the cooperative control techniques we are developing in Among the research currently underway at the Vijay Kumar Lab at thethe ARCAS project, it will be possible to share the weight of the carried University of Pennsylvania is a project called Cooperative Manipulationstructures over a platoon of robots, hence further increasing the overall and Transport. This seeks to solve the problem of how autonomous robotspayload capacity, says Professor Vincenzo Lippiello from the University of can be made to work together to move large payloads by looking to nature.Naples Federico II and one of the ARCAS researchers.The team draws inspiration from ants and the way they collaborate toBut Lippiello says this brings on another set of challenges, including transport items of food much larger than the individual ants themselves.designing control laws that take into account the destabilizing effect of Kumar tells us that since his presentation in 2012, his team has improvedhaving several drones hold onto the same object in the air and how sensing the system in two ways. The first is the use of sensors, such as cameras, tocapabilities might be best integrated.Another hurdle that the ARCAS project is working on overcoming is determining the ideal payload for the drones, a predicament that pretty well seems to hang over all researchers working in this area. Its first prototype tested indoors had a payload capacity of 6 kg (13.22 lb), the second saw this increased to 9 kg (20 lb) per vehicle. An upcoming prototype drone will have a total payload of between 15 and 20 kg (33 and 44 lb). It does say, however, that external factors could bring about advances in the carrying capacity.It is true that technological limitations exist and are mainly linked to the power to weight ratio of the current batteries, says Lippiello. But the recent improvements of battery technology, mainly related to the cellular business, have also generated benefits for the drones performance in terms of autonomy and or payload.So the value of drones in construction in terms of aerial mapping and surveying is pretty well established, if not yet entirely realized by the industry. As successful firms such as Komatsu, Siemens and Soto Engineering continue to lead the way, it seems logical that there will be more to follow, especially when we consider that the technology is only becoming cheaper and its benefits harder to ignore.But for actually building the structures themselves? The general line of thinking among the experts weve spoken to for this story is that the technology is at least five to ten years away. But it appears that if it does come to fruition, it will come with its share of limitations. Drones as construction machines may spawn a new niche in architectural design just as the team at ETH Zrich anticipate, or they may cooperate to make light work of moving heavy materials, but even then it seems they will only Among the research projects currently underway at the Vijay Kumar Lab at theamount to a technology that complements the construction industry, rather University of Pennsylvania is one called Cooperative Manipulation and Transport than truly disrupts it.determine the position of the neighboring robot, negating the need forWhat we also know is there will need to be a serious economic case to communication between vehicles. The second is an ability to enroll largerget the drones out of the lab and onto construction sites. Delivery drones numbers of small, ant-like robots in cooperative tasks. Now theoretically,were unheard of until Amazon came along and professed that they had the we can do hundreds, he says. potential to turn its business model on its head, and now here we are, with When it comes to overcoming the payload limitations of drones withthe technology more or less there and pilots projects being carried out all a view to using them in construction, Kumar believes having them workaround the world. For flying robots to form part of construction sites of the together is the best way forward. While scaling the vehicles up could renderfuture, their capabilities will need to align with the private interests behind them capable of moving heavy materials like girders and beams, this willthem. This might involve scenarios where it is just not cost effective or also make them more cumbersome and sacrifice one of their key strengths:physically possible to put human workers on the job.agility. Its likely to be somewhere where labor is prohibitively expensive, or Making individuals more powerful or stronger is possible, although thisworkers cannot go there, imagines Dr Kumar. Think of us colonizing would make this large, unwieldy, heavy and awkward, especially when thereMars. The first things that build for us there will be robots.might be need to maneuver in tight spaces and or adapt to differently sizedSo if you think that using drones in construction is a pretty out of this payloads, he says. This is why we prefer the small, modular solution. It isworld idea, in the end, you may just be proven right.not only bio-inspired and elegant, it is also more practical and economical.26 www.mrca.orgMidwest Roofer'