The pivotal role of blockchain technology in securing robot swarms An EU-funded project sheds light on how the union of blockchain with distributed robotic systems can pave the way for safe, reliable and trustworthy swarm robotic systems. Digital Economy © Eduardo Castelló Ferrer Inspired by nature, swarm robotics – the use of multiple robots that accomplish a task by forming structures and behaviours similar to the ones observed in natural systems – is expected to transform many industrial applications such as logistics and last mile delivery. However, the very characteristics that make these robots ideal for certain applications like robot autonomy and decentralised control present obstacles when it comes to transferring the technology from academic institutions to real-world problems. One such challenge is the concern over a lack of security standards in the field. Blockchain, an emerging technology originating in the digital currency field, is proving to be an effective way to achieve tamper-resistant, secure data sharing systems. The combination of blockchain with distributed robotic systems therefore opens the door for more secure, autonomous, flexible systems. The EU-funded BROS project, with the support of the Marie Skłodowska-Curie Actions (MSCA) programme, set out to investigate this synergy. “Specifically, we worked towards understanding how we make swarms of robots secure and make decisions without a centralised authority and how solutions can be implemented in real-robot swarms,” explains Marie Skłodowska-Curie fellow Eduardo Castelló Ferrer. Profound results from mixing two technologies “We designed, analysed and programmed several models and methods that combined blockchain-based technology and robotics in general and swarm robotics in particular,” notes Ferrer. Even though it was the first time that this combination was explored, the project managed to prove, from a theoretical point of view, the feasibility of combining both techniques to solve current problems in the field, such as security and distributed decision-making. The developed models and methods were then later validated through a series of experiments implemented in real-robot systems. “These experiments, for instance, show for the first time that a Merkle tree – a fundamental technology in the blockchain space – is a feasible method for encapsulating cooperative and collaborative robotic missions without disclosing high-level information about the mission itself,” adds Ferrer. In other words, robots can verify whether an individual job is part of a collective mission or not without knowing the outcome of the mission. “In technical terms, data verification can be separated from the data itself.” The project also offered a system whereby robots in a swarm, to cooperate in mission completion, have to ‘prove’ their integrity to their peers by exchanging cryptographic proofs. “In a nutshell, we realised that key future aspects for swarm systems such as security, privacy and safe data sharing can be significantly improved by adding blockchain-based technology into their operations,” says Ferrer. Opening doors “After the completion of BROS, we were able to publish high-quality work in several foundational papers which can be found on my website as well as organise the first public academic events in the field of blockchain-based technology for robotics,” concludes Ferrer. This is in addition to the three academic events organised during the project: one workshop and two symposiums to maximise the exposure and dissemination of the project’s work. These symposiums resulted in an emerging academic community of researchers, scientists and artists, amongst others, who developed an interest in the field of blockchain robotics. Keywords BROS, blockchain, security, swarm robotics, data sharing, robot systems, data verification
