Exploring Tactile Resonance Sensors: The Revolutionary Force and Challenges in the Medical Field

In the past few decades, with the gradual maturation of robotics, especially in medical applications, tactile sensors based on various sensing principles have been developed. A multitude of technical solutions have been employed to design tactile sensors. Notably, microfabrication-based approaches possess several appealing features. Microfabrication technology enables the development of miniature sensors with excellent performance, which exhibit outstanding metrological characteristics, such as high precision, sensitivity, low power consumption, and favorable frequency response. The compact size and superior metrological properties enhance the potential role of tactile sensors in the medical field, particularly tactile resonance sensors (TRS). Its principle involves measuring the frequency shift f, defined as the difference between the resonance frequency of the freely vibrating sensor and the resonance frequency measured when the sensor encounters an object. Therefore, f is related to the acoustic impedance of the object and can be utilized to characterize its material properties. In the medical domain, tactile resonance sensor systems have been developed for various applications, including cancer detection, assessment of human egg fertility, measurement of intraocular pressure, and diagnosis of edema. In this review, we mainly explore the basic principles, major medical applications, technological advancements, and challenges of TRS. TRS shows remarkable potential in medical application. Although innovations in sensor design and materials have expanded its functions, issues such as signal interference, lack of standardization, and insufficient clinical verification still need to be addressed. Overcoming these challenges is essential for realizing the full potential of TRS in improving medical diagnosis and patient care.