Researchers from the School of Biomedical Engineering & Imaging Sciences and Imperial College London have invented new robotic technology and built MAMMOBOT, a small robot which can pass through mammary ducts to detect early precursors of invasive breast cancers which often originate in these ducts and can otherwise be missed by mammography.

A pre-print shows how the project led by Dr Christos Bergeles from King’s College London and Dr Daniel Leff from Imperial sees the invention of growing robots, robots like everted balloons that can unroll when pressure is applied.

But while the new technology can grow inside lumen, cavities like vessels without causing harm, they cannot be steered. The engineers have added steering capabilities to the growing robots, and in a millimeter-sized device.

Dr Christos Bergeles said the team managed to create a small growing robot that has an open channel through which can pass a steerable catheter.

“The growing robot elongates though pressure, and the steerable catheter makes sure that the tip of the robot is oriented in the right direction,” he said.

Dr Pierre Berthet-Rayne created a first version of MAMMOBOT that is both growing and also steerable, with an overall diameter of around 2mm.

“The 2mm robot elongates to conform to the ductal tree, and the steerable catheter bends to move the tip to the appropriate branch,” Dr Bergeles said.

Researchers say the novelty in the development processes lies in the bespoke manufacturing approach, adaptation of growing robot concept to incorporate elements from steerable catheters, and tailored controller for this type of robot.

The team tested the robot on benchtop to showcase that the robot can both grow and steer.

Dr Hadi Sadati created a basic model of the growing and steerable elements, showing that the robot’s shape could adequately be predicted. This means that the team knew how to steer it inside the anatomy.

The team now has the building blocks to achieve this.

The research project was developed during a sandpit, co-organised by Cancer Research UK and EPSRC, which was designed to identify robotic technologies that can lead to early detection of cancer.

The researchers are working now on recreating the setup in a more robust fashion, using better motors and components.

“We aim to introduce shape and force sensing capabilities and generate preliminary results in support of a larger grant application,” Dr Bergeles said.

The steering technology is considered in a patent application. The team is keen to explore licensing opportunities in the UK and internationally.