To improve dynamic and static performances and robustness of the induction motor speed control system based on vector control,an improved fractional-order intelligent proportional integral(IPIλ)controller was applied...To improve dynamic and static performances and robustness of the induction motor speed control system based on vector control,an improved fractional-order intelligent proportional integral(IPIλ)controller was applied to the speed controller of the vector control system,which combined the intelligent fractional integral with the proportion according to the variation of deviation.Compared with proportional integral(PI)and fractional-order proportional integral(FOPI)controllers,the IPIλcontroller achieved better control performance.The stimulation results indicate that the IPIλcontroller can not only track the given speed quickly and accurately,but also have better anti-interference and robustness for load and parameters variations.展开更多
In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current re...In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current response（TCR） at 136 mm diameter,where the resonance occurs at 2.4kHz and the peak value of 118 dB re 1 μPa/A at 1 m occurs at 12 kHz.Also bolt at a 46mm distance from the center of the head mass offers resonance at 2.4kHz,and the peak value of 115.3 dB re 1 μPa/A at 1m occurs at 11.5kHz.This optimized design is fabricated and molded with polyurethane of 3mm thickness.The prototype was tested at the Acoustic Test Facility（ATF） of National Institute of Ocean Technology（NIOT） for its underwater performances.Based on the result,the fundamental resonance was determined to be 2.18kHz and the peak value of TCR of 182 dB re 1 μPa/A at 1m occurs at 14 kHz.The maximum value of the RS was found to be -190 dB re 1V/μPa at 1m at a frequency of 2.1kHz.展开更多
A twisted fiber optic sensor based on intensity modulation is described. The principle and structure of the sensor and the choice of steel strand modules are introduced. The sensor is used to determine the tensile str...A twisted fiber optic sensor based on intensity modulation is described. The principle and structure of the sensor and the choice of steel strand modules are introduced. The sensor is used to determine the tensile strain and distribution. The experimental results show that the change of the transferring light power has an approximate linear relation with the outer force. The intelligent steel strands with this kind of sensor will have a good application in monitoring the concrete crack and deformation distribution in huge structures such as dams and bridges.展开更多
Electronic skins and flexible pressure sensors are important devices for advanced healthcare and intelligent robotics.Sensitivity is a key parameter of flexible pressure sensors.Whereas introducing surface microstruct...Electronic skins and flexible pressure sensors are important devices for advanced healthcare and intelligent robotics.Sensitivity is a key parameter of flexible pressure sensors.Whereas introducing surface microstructures in a capacitive-type sensor can significantly improve its sensitivity,the signal becomes nonlinear and the pressure response range gets much narrower,significantly limiting the applications of flexible pressure sensors.Here,we designed a pressure sensor that utilizes a nanoscale iontronic interface of an ionic gel layer and a micropillared electrode,for highly linear capacitance-to-pressure response and high sensitivity over a wide pressure range.The micropillars undergo three stages of deformation upon loading:initial contact(0-6 k Pa)and structure buckling(6-12 k Pa)that exhibit a low and nonlinear response,as well as a post-buckling stage that has a high signal linearity with high sensitivity(33.16 k Pa-1)over a broad pressure range of 12-176 k Pa.The high linearity lies in the subtle balance between the structure compression and mechanical matching of the two materials at the gel-electrode interface.Our sensor has been applied in pulse detection,plantar pressure mapping,and grasp task of an artificial limb.This work provides a physical insight in achieving linear response through the design of appropriate microstructures and selection of materials with suitable modulus in flexible pressure sensors,which are potentially useful in intelligent robots and health monitoring.展开更多
基金National Natural Science Foundation of China(No.61461023)Gansu Provincial Department of Education Project(No.2016B-036)
文摘To improve dynamic and static performances and robustness of the induction motor speed control system based on vector control,an improved fractional-order intelligent proportional integral(IPIλ)controller was applied to the speed controller of the vector control system,which combined the intelligent fractional integral with the proportion according to the variation of deviation.Compared with proportional integral(PI)and fractional-order proportional integral(FOPI)controllers,the IPIλcontroller achieved better control performance.The stimulation results indicate that the IPIλcontroller can not only track the given speed quickly and accurately,but also have better anti-interference and robustness for load and parameters variations.
文摘In this study,a 2kHz Tonpilz projector was designed using a Terfenol-D and modeled in ATILA.For the purpose of modeling studies,it has been determined that a radiating head mass exhibits better transmitting current response（TCR） at 136 mm diameter,where the resonance occurs at 2.4kHz and the peak value of 118 dB re 1 μPa/A at 1 m occurs at 12 kHz.Also bolt at a 46mm distance from the center of the head mass offers resonance at 2.4kHz,and the peak value of 115.3 dB re 1 μPa/A at 1m occurs at 11.5kHz.This optimized design is fabricated and molded with polyurethane of 3mm thickness.The prototype was tested at the Acoustic Test Facility（ATF） of National Institute of Ocean Technology（NIOT） for its underwater performances.Based on the result,the fundamental resonance was determined to be 2.18kHz and the peak value of TCR of 182 dB re 1 μPa/A at 1m occurs at 14 kHz.The maximum value of the RS was found to be -190 dB re 1V/μPa at 1m at a frequency of 2.1kHz.
文摘A twisted fiber optic sensor based on intensity modulation is described. The principle and structure of the sensor and the choice of steel strand modules are introduced. The sensor is used to determine the tensile strain and distribution. The experimental results show that the change of the transferring light power has an approximate linear relation with the outer force. The intelligent steel strands with this kind of sensor will have a good application in monitoring the concrete crack and deformation distribution in huge structures such as dams and bridges.
基金supported by the Science Technology and Innovation Committee of Shenzhen Municipality(JCYJ20170817111714314)the National Natural Science Foundation of China(52073138 and 51771089)+2 种基金the Guangdong Innovative and Entrepreneurial Research Team Program(2016ZT06G587)the Shenzhen Sci-Tech Fund(KYTDPT20181011104007)the Tencent Robotics X Lab Rhino-Bird Focused Research Program(JR201984)。
文摘Electronic skins and flexible pressure sensors are important devices for advanced healthcare and intelligent robotics.Sensitivity is a key parameter of flexible pressure sensors.Whereas introducing surface microstructures in a capacitive-type sensor can significantly improve its sensitivity,the signal becomes nonlinear and the pressure response range gets much narrower,significantly limiting the applications of flexible pressure sensors.Here,we designed a pressure sensor that utilizes a nanoscale iontronic interface of an ionic gel layer and a micropillared electrode,for highly linear capacitance-to-pressure response and high sensitivity over a wide pressure range.The micropillars undergo three stages of deformation upon loading:initial contact(0-6 k Pa)and structure buckling(6-12 k Pa)that exhibit a low and nonlinear response,as well as a post-buckling stage that has a high signal linearity with high sensitivity(33.16 k Pa-1)over a broad pressure range of 12-176 k Pa.The high linearity lies in the subtle balance between the structure compression and mechanical matching of the two materials at the gel-electrode interface.Our sensor has been applied in pulse detection,plantar pressure mapping,and grasp task of an artificial limb.This work provides a physical insight in achieving linear response through the design of appropriate microstructures and selection of materials with suitable modulus in flexible pressure sensors,which are potentially useful in intelligent robots and health monitoring.
