They design a new material capable of "to think"

Aug. 24 () –

Researchers at the University of Pennsylvania and the United States Air Force have harnessed the human brain’s mechanical information processing in response to external stimuli and they have integrated it into engineering materials that “think.”

The work, published in the journal ‘Nature’, is based on a novel and reconfigurable alternative to integrated circuits. Integrated circuits are usually made up of multiple electronic components housed in a single semiconductor material, usually silicon.and they power all sorts of modern electronics, like phones, cars, and robots.

Integrated circuits are scientists’ realization of information processing, similar to the function of the brain in the human body.

According to lead researcher Ryan Harne, James F. Will Associate Professor of Mechanical Engineering at Penn State, integrated circuits are the core building block needed for scalable computing of signals and information, but they have never before been realized by scientists in a composite. different from that of silicon semiconductors.

His team’s discovery has revealed the possibility of almost any material in our environment acting as its own integrated circuit: being able to “think” about what is happening around it.

“We have created the first example of an engineered material that can simultaneously sense, think and act on mechanical stress without the need for additional circuitry to process such signals,” explains Harne. The soft polymeric material acts like a brain that can receive digital strings of information that are then processed, giving rise to new strings of digital information that can control reactions.”

The soft, conductive mechanical material contains reconfigurable circuitry that can perform combinational logic: when the material receives external stimuli, it translates the input into electrical information that is then processed to create output signals.

The material could use mechanical force to perform complex arithmetic, as Harne and his team showed, or detect radio frequencies to communicate specific light signals, among other potential examples of translation. He says the possibilities are vast because integrated circuits can be programmed to do many things.

“We discovered how to use mathematics and kinematics (how the individual components of a system move) in mechanical-electrical networks,” he says. “This allowed us to realize a fundamental way of intelligence in engineering materials by facilitating fully scalable information processing intrinsic to the soft materials system“.

According to Harne, the material uses a human-like “thinking” process and has potential applications in autonomous search and rescue systems, infrastructure repair, and even biohybrid materials capable of identifying, isolating, and neutralizing airborne pathogens. air.

“What makes humans intelligent is our ability to observe and think about the information we receive through our senses, reflecting on the relationship between that information and how we can react,” says Harne.

Although our reactions seem automatic, the process requires nerves in the body to digitize sensory information so that electrical signals can travel to the brain. The brain receives this informative sequence, evaluates it and tells the body to react accordingly..

For the materials to process and think about information in a similar way, they must perform the same intricate internal calculations, Harne explains. When researchers subject their engineering material to mechanical information–an applied force that deforms the material–it digitizes the information into signals that its power grid can advance and evaluate.

The process builds on the team’s previous work to develop a soft mechanical metamaterial that can “think” about forces applied to it and respond through programmed reactions, detailed in Nature Communications last year.

According to Harne, this earlier material was limited to logic gates that worked with binary input and output signals, and had no way of computing high-level logic operations that are fundamental to integrated circuits.

The researchers were stuck, until they rediscovered a 1938 paper published by Claude E. Shannon, who would later be known as the “father of information theory.”

Shannon described a way to create an integrated circuit by building mechanical-electrical switching networks that follow the laws of Boolean mathematics, the same binary logic gates that Harne used earlier.

“Ultimately, the semiconductor industry did not adopt this method of manufacturing ICs in the 1960s, opting instead for a direct assembly approach,” he recalls. “Shannon’s math-based design philosophy , was lost to the sands of time, so when we read the article, we were surprised that our preliminary work exactly realized Shannon’s vision.”

However, Shannon’s work was hypothetical, produced almost 30 years before integrated circuits were developed, and did not address how to scale networks.

“We made significant modifications to Shannon’s design philosophy to bring our mechanical-electrical networks into line with the reality of integrated circuit assembly standards. – – continues Harne -. We leapfrogged our logic gate design philosophy from the core of 2021 research and fully synchronized design principles with those articulated by Shannon to ultimately obtain mechanical IC materials, the effective brain of artificial matter.”

The researchers are now evolving the material so that it processes visual information as it does physical cues.

“We are currently translating this into a ‘see’ medium to augment the ‘touch’ sensation that we have currently created Harne announces. Our goal is to develop a material that demonstrates autonomous navigation through an environment by seeing cues, following them, and maneuvering to get out of the way of an adverse mechanical force, such as something stepping on you.”