The low-altitude transport has demonstrated significant growth potential driven by rapid advancements in unmanned aerial vehicles(UAVs)technology.Herein,rotor UAVs are increasingly favored by consumers due to their un...The low-altitude transport has demonstrated significant growth potential driven by rapid advancements in unmanned aerial vehicles(UAVs)technology.Herein,rotor UAVs are increasingly favored by consumers due to their unique advantages.The UAVs motion is altered by adjusting propeller speed,which is governed by motor speed.Consequently,motor speed is a key factor influencing flight performance that is susceptible to environmental interference.Accurate and real-time monitoring of motor speed is essential.Conventional speed sensors are bulky,reliant on external power,and challenging to integration into compact UAVs systems.They also suffer from insufficient accuracy and unstable measurements,particularly with small motors.This article introduces a self-powered digital aircraft rotational speed sensor(SDARSS)utilizing a rotating triboelectric nanogenerators(TENGs)to address current challenges.This sensor is lightweight,energy-efficient,and self-powered,weighing only 2.185 g and measuring 3.43 mm in thickness,with an accuracy exceeding 99.94%.It measures speeds up to 10,000 revolutions per minute(rpm)with exceptional precision and stability.The sensor enables real-time monitoring of UAVs motor speeds,which is crucial for enhancing flight safety.展开更多
Extensive urban areas worldwide face significant landslide hazards, impacting inhabitants, buildings, and critical infrastructures alike. In the case of slow-moving deep-seated landslides involving huge areas and char...Extensive urban areas worldwide face significant landslide hazards, impacting inhabitants, buildings, and critical infrastructures alike. In the case of slow-moving deep-seated landslides involving huge areas and characterized by complex patterns, when the cost of repairing infrastructures, relocating communities, and restoring cultural sites might be such that it is unsustainable for the community, the exposed structures require significant effort for their surveillance and protection, which can be supported by the development of innovative monitoring systems. For this purpose, a smart extenso-inclinometer, realized by equipping a conventional inclinometer tube with distributed strain and temperature transducers based on optical fiber sensing technology, is presented. In situ monitoring of the active deep-seated San Nicola landslide in Centola (Campania, southern Italy) demonstrated its ability to capture the main features of movements and reconstruct a tridimensional evolution of the landslide pattern, even when the entity of both vertical and horizontal soil strain components is comparable. Although further tests are needed to definitively ascertain the extensometer function of the new device, by interpreting the strain profiles of the landslide body and identifying the achievement of predetermined thresholds, this system could provide a warning of the trigger of a landslide event. The use of the smart extenso-inclinometer within an early warning system for slow-moving landslides holds immense potential for reducing the impact of landslide events.展开更多
Geotechnical engineering is characterized by many uncertainties,including soil material properties,environmental effects,and engineering design and construction,which bring a significant challenge to geotechnical moni...Geotechnical engineering is characterized by many uncertainties,including soil material properties,environmental effects,and engineering design and construction,which bring a significant challenge to geotechnical monitoring.However,conventional sensors with several inherent limitations,such as electromagnetic interference,signal loss in long-distance transmission,and low durability in harsh environments cannot fully meet current monitoring needs.Recently,fiber optic sensing technologies have been successfully applied in geotechnical monitoring due to the significant advantages of anti-electromagnetic interference,stable signal long-distance transmission,high durability,high sensitivity,and lightweight,which can be considered an ideal replacement for conventional sensors.In this paper,the working principle of different fiber optic sensing technologies,the development of fiber optic-based sensors,and the recent application status of these sensing technologies for geotechnical monitoring were comprehensively reviewed and discussed in detail.Finally,the challenges and countermeasures of the sensing technologies in geotechnical monitoring were also presented and discussed.展开更多
基金supported by the National Natural Science Foundation of China(No.52203324)the National Key R&D Program of China(No.2023YFB2604600)+1 种基金the National Key R&D Project from the Minister of Science and Technology(No.2021YFA1201601)Thanks to the Georgia Institute of Technology for providing software support。
文摘The low-altitude transport has demonstrated significant growth potential driven by rapid advancements in unmanned aerial vehicles(UAVs)technology.Herein,rotor UAVs are increasingly favored by consumers due to their unique advantages.The UAVs motion is altered by adjusting propeller speed,which is governed by motor speed.Consequently,motor speed is a key factor influencing flight performance that is susceptible to environmental interference.Accurate and real-time monitoring of motor speed is essential.Conventional speed sensors are bulky,reliant on external power,and challenging to integration into compact UAVs systems.They also suffer from insufficient accuracy and unstable measurements,particularly with small motors.This article introduces a self-powered digital aircraft rotational speed sensor(SDARSS)utilizing a rotating triboelectric nanogenerators(TENGs)to address current challenges.This sensor is lightweight,energy-efficient,and self-powered,weighing only 2.185 g and measuring 3.43 mm in thickness,with an accuracy exceeding 99.94%.It measures speeds up to 10,000 revolutions per minute(rpm)with exceptional precision and stability.The sensor enables real-time monitoring of UAVs motor speeds,which is crucial for enhancing flight safety.
基金supported by Universita della Campania“L.Vanvitelli”,Program VALERE“VAnviteLli pEr la RicErca”(Grant No.516/2018)Italian Ministry of Economic Development#NOACRONYM Project,PoC MISE 2021.
文摘Extensive urban areas worldwide face significant landslide hazards, impacting inhabitants, buildings, and critical infrastructures alike. In the case of slow-moving deep-seated landslides involving huge areas and characterized by complex patterns, when the cost of repairing infrastructures, relocating communities, and restoring cultural sites might be such that it is unsustainable for the community, the exposed structures require significant effort for their surveillance and protection, which can be supported by the development of innovative monitoring systems. For this purpose, a smart extenso-inclinometer, realized by equipping a conventional inclinometer tube with distributed strain and temperature transducers based on optical fiber sensing technology, is presented. In situ monitoring of the active deep-seated San Nicola landslide in Centola (Campania, southern Italy) demonstrated its ability to capture the main features of movements and reconstruct a tridimensional evolution of the landslide pattern, even when the entity of both vertical and horizontal soil strain components is comparable. Although further tests are needed to definitively ascertain the extensometer function of the new device, by interpreting the strain profiles of the landslide body and identifying the achievement of predetermined thresholds, this system could provide a warning of the trigger of a landslide event. The use of the smart extenso-inclinometer within an early warning system for slow-moving landslides holds immense potential for reducing the impact of landslide events.
基金funded by the National Natural Science Foundation of China(grant no.52122805,52078103,42225702).
文摘Geotechnical engineering is characterized by many uncertainties,including soil material properties,environmental effects,and engineering design and construction,which bring a significant challenge to geotechnical monitoring.However,conventional sensors with several inherent limitations,such as electromagnetic interference,signal loss in long-distance transmission,and low durability in harsh environments cannot fully meet current monitoring needs.Recently,fiber optic sensing technologies have been successfully applied in geotechnical monitoring due to the significant advantages of anti-electromagnetic interference,stable signal long-distance transmission,high durability,high sensitivity,and lightweight,which can be considered an ideal replacement for conventional sensors.In this paper,the working principle of different fiber optic sensing technologies,the development of fiber optic-based sensors,and the recent application status of these sensing technologies for geotechnical monitoring were comprehensively reviewed and discussed in detail.Finally,the challenges and countermeasures of the sensing technologies in geotechnical monitoring were also presented and discussed.
