Real-time detection of low-speed motion and precise monitoring of low-intensity exercise are crucial for smart fitness systems.These capabilities enable continuous data acquisition,capture subtle motion variations for...Real-time detection of low-speed motion and precise monitoring of low-intensity exercise are crucial for smart fitness systems.These capabilities enable continuous data acquisition,capture subtle motion variations for personalized guidance,and enhance training effectiveness while reducing the risk of injury.However,conventional rotational speed sensors often exhibit signal loss and limited responsiveness at low speeds,leading to inaccurate feedback and constraining the development of intelligent fitness devices.Therefore,this paper proposes a triboelectric rotational speed sensor(TRSS),which employs a coaxial reverse magnetic modulation transmission mechanism to enhance low-speed monitoring,thereby overcoming low-speed signal loss.The sensor enables real-time detection of rotational speed in fitness equipment,and features a compact structure,doubled resolution,and high detection accuracy of 0.21 rad s−1.Performance test indicates a sensitivity of 3.15 Hz(rad s−1)−1,a linear correlation coefficient of 0.99892,and an average error of 1.19%in simulated tests,which demonstrates the capability of the sensor for accurate motion monitoring at low speeds.Furthermore,a triboelectric magnetic-modulated rotational monitoring system(TMRMS)is developed and validated through cycling experiments,demonstrating excellent performance across a wide speed range.These findings highlight the strong potential of the system for advancing next-generation smart fitness applications.展开更多
The monitoring of an accurate speed is crucial for driving safety,traffic efficiency,and environmental protection.However,the existing commercial wheel speed sensors require external power and costly maintenance.Tribo...The monitoring of an accurate speed is crucial for driving safety,traffic efficiency,and environmental protection.However,the existing commercial wheel speed sensors require external power and costly maintenance.Triboelectric nanogenerators(TENGs)offer significant advantages for self-powered sensing due to their sensitivity to environmental changes.Therefore,the present study has introduced a planetary gear structure that is known for its efficient transmission and smooth operation characteristics.A planetary gear-driven triboelectric speed sensor(PGTS)has also been designed.The structural optimization was performed by combining finite element analysis with experimental results.At a speed of 120 rpm,the open-circuit voltage and short-circuit current could reach 10 V and 0.2μA,respectively.Also,a peak power of 1.51μW was achieved at a load resistance of 30 MΩ.A high-precision revolution speed sensing algorithm was further developed for a real-time and accurate perception of the vehicle speed.The research results demonstrated that the PTGS was successfully integrated into the small-scale indoor tire-road testing platform,achieving a sensing accuracy of up to 99% in measuring the revolution speed.Furthermore,real vehicle tests were conducted using a Volkswagen Passat,and the fitting goodness-of-fit for the vehicle speed perception still reached 99%,with a minimum realtime fitting accuracy of 80.25%.Finally,a high-performance vehicle emergency monitoring system based on the vehicle slip rate level was proposed for monitoring abnormal vehicle behavior,which could promote a safety upgrade of the autonomous driving technology.展开更多
As mine excavation deepens,ventilation systems often face the challenge of insufficient airflow,while the complex environment poses significant obstacles to powering monitoring and alarm sensors.Here,an integrated and...As mine excavation deepens,ventilation systems often face the challenge of insufficient airflow,while the complex environment poses significant obstacles to powering monitoring and alarm sensors.Here,an integrated and efficient self-powered mine wind speed monitoring and alarm system(SLW-MAS)is proposed based on triboelectric nanogenerator(TENG).The SLW-MAS,featuring a centrifugal structure design,facilitates hierarchical control of the TENG module,thereby enabling differential responses to wind speeds.When the wind speed is lower than 1.5 m/s,the TENG module is maintained in a horizontal working state under the action of the centrifugal mechanism and produces a high voltage output;the switch circuit is selected through experiments,which makes it meet the alarm delay of 2 s and avoids the problem of inaccurate alarm caused by unstable airflow.This work provides the feasibility for the construction of an underground distributed Internet of Things monitoring and alarm system.展开更多
基金supported by the National Key R&D Project from Minister of Science and Technology(Grant No.2021YFA1201604)Beijing Natural Science Foundation(Grant No.3244038)+1 种基金GuangDong Basic and Applied Basic Research Foundation(Grant No.2024A1515140103)Jilin Province Development and Reform Commission(Grant No.2024C006-3).
文摘Real-time detection of low-speed motion and precise monitoring of low-intensity exercise are crucial for smart fitness systems.These capabilities enable continuous data acquisition,capture subtle motion variations for personalized guidance,and enhance training effectiveness while reducing the risk of injury.However,conventional rotational speed sensors often exhibit signal loss and limited responsiveness at low speeds,leading to inaccurate feedback and constraining the development of intelligent fitness devices.Therefore,this paper proposes a triboelectric rotational speed sensor(TRSS),which employs a coaxial reverse magnetic modulation transmission mechanism to enhance low-speed monitoring,thereby overcoming low-speed signal loss.The sensor enables real-time detection of rotational speed in fitness equipment,and features a compact structure,doubled resolution,and high detection accuracy of 0.21 rad s−1.Performance test indicates a sensitivity of 3.15 Hz(rad s−1)−1,a linear correlation coefficient of 0.99892,and an average error of 1.19%in simulated tests,which demonstrates the capability of the sensor for accurate motion monitoring at low speeds.Furthermore,a triboelectric magnetic-modulated rotational monitoring system(TMRMS)is developed and validated through cycling experiments,demonstrating excellent performance across a wide speed range.These findings highlight the strong potential of the system for advancing next-generation smart fitness applications.
基金supported by the National Key R&D Program of China(No.2023YFB2604600)the International Cooperation Project of Science and Technology Commission of Shanghai Municipality(No.22210710700)+1 种基金the National Natural Science Foundation of China(No.52278455)the Shuguang Program of Shanghai Education Development Foundation and Shanghai Municipal Education Commission(No.21SG24).
文摘The monitoring of an accurate speed is crucial for driving safety,traffic efficiency,and environmental protection.However,the existing commercial wheel speed sensors require external power and costly maintenance.Triboelectric nanogenerators(TENGs)offer significant advantages for self-powered sensing due to their sensitivity to environmental changes.Therefore,the present study has introduced a planetary gear structure that is known for its efficient transmission and smooth operation characteristics.A planetary gear-driven triboelectric speed sensor(PGTS)has also been designed.The structural optimization was performed by combining finite element analysis with experimental results.At a speed of 120 rpm,the open-circuit voltage and short-circuit current could reach 10 V and 0.2μA,respectively.Also,a peak power of 1.51μW was achieved at a load resistance of 30 MΩ.A high-precision revolution speed sensing algorithm was further developed for a real-time and accurate perception of the vehicle speed.The research results demonstrated that the PTGS was successfully integrated into the small-scale indoor tire-road testing platform,achieving a sensing accuracy of up to 99% in measuring the revolution speed.Furthermore,real vehicle tests were conducted using a Volkswagen Passat,and the fitting goodness-of-fit for the vehicle speed perception still reached 99%,with a minimum realtime fitting accuracy of 80.25%.Finally,a high-performance vehicle emergency monitoring system based on the vehicle slip rate level was proposed for monitoring abnormal vehicle behavior,which could promote a safety upgrade of the autonomous driving technology.
基金support from the National Key Research and Development Program of China(No.2021YFA1201601)the Beijing Natural Science Foundation(Nos.L244004 and 3244038)the Macao university of Science and Technology Faculty Research Grants(General Research Grants,GRFs)(No.FRG-24-084-FIE).
文摘As mine excavation deepens,ventilation systems often face the challenge of insufficient airflow,while the complex environment poses significant obstacles to powering monitoring and alarm sensors.Here,an integrated and efficient self-powered mine wind speed monitoring and alarm system(SLW-MAS)is proposed based on triboelectric nanogenerator(TENG).The SLW-MAS,featuring a centrifugal structure design,facilitates hierarchical control of the TENG module,thereby enabling differential responses to wind speeds.When the wind speed is lower than 1.5 m/s,the TENG module is maintained in a horizontal working state under the action of the centrifugal mechanism and produces a high voltage output;the switch circuit is selected through experiments,which makes it meet the alarm delay of 2 s and avoids the problem of inaccurate alarm caused by unstable airflow.This work provides the feasibility for the construction of an underground distributed Internet of Things monitoring and alarm system.
