Developed by engineers at King’s College London, the system could allow robots to access extreme environments where electricity-powered devices do not work, such as irradiated areas like Chernobyl or electrically sensitive MRI rooms in hospitals.
Robots typically rely on electricity and computer chips to function. A robotic ‘brain’ of algorithms and software translates information through an encoder to the hardware, which then performs an action. The new compact circuit instead transmits commands using variations in pressure of an internal fluid.
“Put simply, robots are split into two parts: the brain and the body. An AI brain can help run the traffic system of a city, but many robots still struggle to open a door – why is that?” asked Dr Antonio Forte, senior lecturer in engineering at King’s and senior author of the new study.
“Software has advanced rapidly in recent years, but hardware has not kept up. By creating a hardware system independent from the software running it, we can offload a lot of the computational load onto the hardware, in the same way your brain doesn’t need to tell your heart to beat.”
Using hard electronic encoders is a particular problem in soft robotics, which creates muscle-like systems out of soft materials. Software is also put under strain by demands for materials to act in complex ways.
To circumvent this, the team developed a reconfigurable circuit with an adjustable valve, to be placed within a robot’s hardware. The valve acts like a transistor in a normal circuit, allowing engineers to send signals directly to the hardware using pressure. Similar to binary code, the variations in pressure allow the robot to perform complex manoeuvres without the need for electricity or instructions from the central ‘brain’.
Soft robots are “really promising” for deployment in extreme environments or interactions with people, said robotics and AI specialist Professor Dimitrios Kanoulas from University College London, who was not involved in the work. The ‘fluidic oscillatory circuits’ are “very clever” as they allow robot designers to target one or two adjustable parameters, he said to Professional Engineering.
“You don't need to control anything, so you design a particular robot for a particular application,” he said. To achieve a certain movement – jumping or walking, for example – at a certain frequency, robot makers simply need to redesign the valve. “They achieve simplicity without sacrificing energy,” Prof Kanoulas said.
This simplicity means the system will likely be suited to straightforward motions such as grasping, he said. The team’s first devices include a soft robotic ‘hopper’ and a ‘crawler’ that can move in multiple directions. Complex applications such as dexterous control of human-like hands would be more challenging, and would likely require multiple circuits.
By using fluid circuits, the King’s researchers said robots could free up computational space for other processes, potentially including AI-powered software.
“Delegating tasks to different parts of the body frees up computational space for robots to ‘think’, allowing future generations of robots to be more aware of their social context or even more dexterous. This opens the door for a new kind of robotics in places like social care and manufacturing,” said Dr Forte.
This sounds promising, said Prof Kanoulas, and should allow robots to save energy and space that might otherwise be used on movement. As well as irradiated environments, he suggested that machines with fluid circuits could also be useful in other situations such as underwater exploration.
The King’s team now aims to scale up its circuits from hoppers and pipette dispensers to embed them in larger robots. These could include ‘crawlers’ that monitor power stations, or even wheeled robots with entirely soft engines.
“Ultimately, without investment in embodied intelligence, robots will plateau,” said Mostafa Mousa, post-graduate researcher at King’s and author on the study. “Soon, if we do not offload the computational load that modern day robots take on, algorithmic improvements will have little impact on their performance. Our work is just a first step on this path, but the future holds smarter robots with smarter bodies.”
The work was published in Advanced Science.
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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.