Blockchains and robots

When thinking about all the possible ways to use blockchains and cryptocurrencies, robots don't usually come to mind first. But you may be wrong if you think that blockchains have nothing to do there.

In fact, according to a new research published two weeks ago, blockchains could greatly help flock of robots to communicate with each other, perform a common task, and even avoid attacks that would disturb their goal.

The research, conducted in Belgium, is focused on "robot swarms", or groups of physical robots designed to show a collective behaviour when acting together. For this matter, "consensus achievement" is a crucial capability, for example for path selection, spatial aggregation, or collective sensing. But "the presence of malfunctioning and malicious robots [called Byzantine robots later on] can make it impossible to achieve consensus using classical consensus protocols," the researchers explain.

Hence blockchain.

The engineers used a robot simulator to study how a set of 20 robots perform when they actually rely on a local version of the Ethereum blockchain. In the experiment, each robot acts as an Ethereum node, the swarm forming its own Ethereum network, and the whole system being managed by smart contracts. Although this experimental network is different from the Ethereum MainNet, the blockchain is used in a conventional way: each robot keeps a local copy of the blockchain, replicated to its close neighbours, and each robot actually mines, performing the Proof-of-Work and being rewarded by 5 ether when it solves a block.

And it works.

"The blockchain-controlled swarm could reach a decentralized consensus, even in the presence of Byzantine (adversary) robots. Therefore, it is autonomous and resilient, while the classical approaches are not," the study reads.

The system resists quite well to attacks too. "The robots cannot 'spam' or 'flood' the network with transactions since they would quickly run out of ether. The robots also cannot steal the identity of other robots (spoofing attack) due to digital signatures. Therefore, the blockchain approach stays resilient, even in the presence of a relatively high number of Byzantine robots. Based on these results, one of the main advantages of this approach is visible: the blockchain is able to introduce /scarcity/ into a decentralized swarm, making the system more secure."

Additional work is needed to elaborate on the concept (the researchers will experiment with different blockchains, such as Hyperledger, Cardano and Tezos, in the future).

But the results are promising and blockchain-based robot swarms may be useful in many use cases, such as area exploration, collective mapping, robot-to-robot economies, or any other scenario involving collective decision-making. And, of course, the same principles could be applied not just to robots, but to any devices in the Internet of Things (IoT), or any vehicles.

A blockchain-based robotic future

All in all, roboticists seem to be more and more interested by blockchains.

In 2018, a conference by MIT's Eduardo Castelló Ferrer explained that "the combination of blockchain with other distributed systems, such as robotic swarm systems, can provide the necessary capabilities to make robotic swarm operations more secure, autonomous, flexible and even profitable."

Last year, researchers in Portugal proposed a "RobotChain" — a method to securely register robotic events using a blockchain — for anomaly detection.

And one of the researchers involved, Vasco Ferrinho Lopes, described in another study different methods to optimize robot work using the Tezos blockchain, in order to securely store robot logs (using smart-contracts as storage), and to help detect the presence of material to be picked, or the presence of persons inside the critical zone surrounding the robot. "With this work, we show how blockchain can be used in robotic environments and how it can be beneficial in contexts where multi-party cooperation, security, and decentralization of the data is essential," Lopes concluded.

Your robotic dog may talk blockchain sooner than you think.