Researchers from The Hong Kong University of Science and Technology (HKUST) have developed a sensor array design technology inspired by the human auditory system. By mimicking the human ear’s ability to differentiate sounds through tonotopy, this progressive sensor array approach could optimize the applying of sensor arrays in fields resembling robotics, aviation, healthcare, and industrial machinery.
Traditional sensor arrays face challenges resembling complex wiring, limited reconfigurability, and low damage resistance. The design developed by the HKUST team, led by Associate Professor YANG Zhengbao from the Department of Mechanical & Aerospace Engineering, addresses these challenges by assigning a novel frequency to every sensor unit and using the sensor unit signal to modulate the amplitude of the frequency signal, much like the distinct frequencies processed by hair cells within the human cochlea.
These amplitude-modulated signals of various frequencies are then superimposed onto a single conductor, and a Fast Fourier Transform algorithm is finally used to decipher the person signals. This design allows the reduction of numerous output wires from the standard row-column setup to a single wire, without sacrificing functionality. This progressive method allows the decoding system to process information from all sensor units concurrently, which is a stark contrast to the prevailing implementation of time-division multiplexing for sensor array decoding.
The research team leverages a redundancy design within the sensor connection network to make sure continuous operation, even when parts of the array’s connection network are damaged. This design feature is inspired by the multiple synaptic connections between hair cells in the interior ear and neurons, providing a backup should one pathway fail. This redundant design not only enhances the system’s damage tolerance but in addition enables greater reconfigurability, a feature that is especially useful in rapidly changing environments resembling responsive robotics or adaptable wearable devices. The Lego-style modular design could also result in cost savings in maintenance, because it is simpler to repair than traditional multi-wire sensor arrays.
The proposed sensor array technology offers a mess of potential applications. Its flexibility and robustness make it ideally fitted to integration into curved surfaces and operation in harsh environments. It might probably adapt to the form and multimodal sensing requirements of the surface while providing real-time data. In practical terms, the team has demonstrated the sensor array’s functionality in two primary applications — a pressure sensor array and a pressure-temperature multimodal sensor array. The latter is especially noteworthy for its potential to watch critical parameters in medical prosthetics, thereby enhancing comfort and safety for users. The team has also underscored the technology’s potential for monitoring strain distribution in airplane wings, which could contribute to the event of safer and more fuel-efficient aircraft.
Despite its many benefits, this sensor array design does encounter some limitations. The variety of sensor units within the array is constrained by the operational bandwidth of the circuits, and the potential for miniaturization is proscribed by the scale of the off-the-shelf electronic components required for every sensor unit. Looking ahead, the HKUST team goals to further simplify the sensor array’s design and seek business partnerships to bring this technology to the market.
The team’s findings, realized in collaboration with City University of Hong Kong, were recently published within the journal Science Advances in an article titled “One-wire reconfigurable and damage-tolerant sensor matrix inspired by the auditory tonotopy.” Dr. LONG Zhihe and Mr. LIN Weikang are the primary authors of this work.
