DIGITAL LIFE

US scientists create flexible robot that walks inside blood vessels to treat cardiovascular diseases

A small, soft, flexible robot capable of crawling through earthquake rubble to locate victims or entering the human body to administer medicine could be a reality, leaving science fiction behind.

Researchers at Pennsylvania State University in the US are making this project a reality by combining flexible electronics with magnetically controlled movement. Information from Scitechdaily.

Unlike traditional rigid robots, soft robots are made of malleable materials that replicate the movements of living organisms. This flexibility allows them to move in confined spaces, such as rubble or the complex interior of the human body.

Despite the potential, incorporating sensors and electronics into these flexible systems remains a major challenge, according to Huanyu “Larry” Cheng, James L. Henderson Jr. Memorial Associate Professor of Mechanical Engineering Science at Pennsylvania State University.

“In most applications, soft robotics have been one-way communication systems, meaning they rely on external control to navigate complex environments. Our goal is to integrate smart sensors so that these robots can interact with their environment and operate with minimal human intervention,” said Cheng, co-corresponding author of the team’s study published in the journal Nano-Micro Letters. Cheng and his team recorded videos of the robots in action, capturing their dynamic behavior as they crawled and curled up into a ball to move along a simple path. 

The robots move using rigid magnetic materials embedded in their flexible structures, which allow them to respond predictably to an external magnetic field. By adjusting the strength and direction of the field, the researchers can control the robots’ movements—such as bending, twisting, or crawling—without the need for an internal power source or physical connections, such as wires. With magnetic interference minimized, the robots can be remotely guided by electromagnetic fields or portable magnets—reducing the need for human intervention. In addition, the built-in sensors allow them to react autonomously to environmental stimuli. In search-and-rescue operations, for example, they are smart enough to navigate through rubble by detecting heat or obstacles. 

In medical applications, they can respond to changes in pH or pressure, ensuring precise delivery of medication or accurate collection of samples. The next step for Cheng’s team is to improve the technology for these applications — including creating a “pill robot.” “If we can make these robots even smaller, they could be injected into blood vessels to treat cardiovascular disease or deliver drugs directly to affected areas,” Cheng said. “This would open up entirely new possibilities for noninvasive medical treatments.” 

Research challenges...The outlook is optimistic, but the challenges are great. A major hurdle in developing the technology has been figuring out how to keep the flexible electronics from getting in the way of the robot’s movement.

“Even though we designed the electronics to be flexible, their stiffness is still hundreds or even thousands of times greater than that of the robot’s soft material,” Cheng said. “To overcome this, we distributed the electronics throughout the structure, reducing their impact on movement.” Another challenge was blocking unwanted electrical interference, which can disrupt the operation of an electronic device or system. 

This interference comes from external sources, such as other electronic devices or wireless signals, and can disrupt movement and affect the performance of the sensors. “Magnetic fields are crucial for controlling movement, but they can also interfere with electronic signals,” Cheng noted. “We had to carefully design the layout of the electronic circuits to minimize these interactions, ensuring that the sensors would continue to function even in the presence of strong magnetic fields.”

mundophone