A new modified LuGre friction model is presented for electromagnetic valve actuator system.The modification to the traditional LuGre friction model is made by adding an acceleration-dependent part and a nonlinear cont...A new modified LuGre friction model is presented for electromagnetic valve actuator system.The modification to the traditional LuGre friction model is made by adding an acceleration-dependent part and a nonlinear continuous switch function.The proposed new friction model solves the implementation problems with the traditional LuGre model at high speeds.An improved artificial fish swarm algorithm(IAFSA)method which combines the chaotic search and Gauss mutation operator into traditional artificial fish swarm algorithm is used to identify the parameters in the proposed modified LuGre friction model.The steady state response experiments and dynamic friction experiments are implemented to validate the effectiveness of IAFSA algorithm.The comparisons between the measured dynamic friction forces and the ones simulated with the established mathematic friction model at different frequencies and magnitudes demonstrate that the proposed modified LuGre friction model can give accurate simulation about the dynamic friction characteristics existing in the electromagnetic valve actuator system.The presented modelling and parameter identification methods are applicable for many other high-speed mechanical systems with friction.展开更多
Predicting and optimizing of the high-speed solenoid on/off valve behaviorrequires an accurate model of the hysteresis loop of the magnetic material used A ferromagnetichysteresis model and a novel algorithm based on ...Predicting and optimizing of the high-speed solenoid on/off valve behaviorrequires an accurate model of the hysteresis loop of the magnetic material used A ferromagnetichysteresis model and a novel algorithm based on fixed-point technique to optimize theelectromagnetic model are introduced By utilizing a modified vector Preisach model of magnetichysteresis and the global genetic optimization algorithm based on partial mapping cross method, theB-H relation loops are identified accurately.展开更多
The spraying of plant protection product(PPP)in orchards is a very hazardous working procedure,owing to the spray drift caused by the uneven operation of conventional axial boom sprayers.This research describes an int...The spraying of plant protection product(PPP)in orchards is a very hazardous working procedure,owing to the spray drift caused by the uneven operation of conventional axial boom sprayers.This research describes an intelligent automated system for precise(PPP)distribution in real-time.It is based on an intelligent decision-making model using ultrasonic measurements of leaf area density under laboratory conditions,which serve to trigger electromagnetic valves(EMV)on the axial boom sprayer.A fuzzy logic algorithm was an integrated part of the intelligent system for controlling the PPP by generating the pulse width modulation signal and applying it through the EMV of the prototype boom sprayer.The results showed that by using an intelligent decision-making model,the same efficiency as with conventional methods could be achieved,but with reduced usage of plant protection products.Thus,the intelligent automated system used 4.8 times less spray mixture than the conventional one.展开更多
基金Project(2015BAG06B00)supported by the National Key Technology Research from Development Program of the Ministry of Science and Technology of China
文摘A new modified LuGre friction model is presented for electromagnetic valve actuator system.The modification to the traditional LuGre friction model is made by adding an acceleration-dependent part and a nonlinear continuous switch function.The proposed new friction model solves the implementation problems with the traditional LuGre model at high speeds.An improved artificial fish swarm algorithm(IAFSA)method which combines the chaotic search and Gauss mutation operator into traditional artificial fish swarm algorithm is used to identify the parameters in the proposed modified LuGre friction model.The steady state response experiments and dynamic friction experiments are implemented to validate the effectiveness of IAFSA algorithm.The comparisons between the measured dynamic friction forces and the ones simulated with the established mathematic friction model at different frequencies and magnitudes demonstrate that the proposed modified LuGre friction model can give accurate simulation about the dynamic friction characteristics existing in the electromagnetic valve actuator system.The presented modelling and parameter identification methods are applicable for many other high-speed mechanical systems with friction.
文摘Predicting and optimizing of the high-speed solenoid on/off valve behaviorrequires an accurate model of the hysteresis loop of the magnetic material used A ferromagnetichysteresis model and a novel algorithm based on fixed-point technique to optimize theelectromagnetic model are introduced By utilizing a modified vector Preisach model of magnetichysteresis and the global genetic optimization algorithm based on partial mapping cross method, theB-H relation loops are identified accurately.
基金This article was partly created as a result of the applied EUREKA project(No.3211-10-000040).
文摘The spraying of plant protection product(PPP)in orchards is a very hazardous working procedure,owing to the spray drift caused by the uneven operation of conventional axial boom sprayers.This research describes an intelligent automated system for precise(PPP)distribution in real-time.It is based on an intelligent decision-making model using ultrasonic measurements of leaf area density under laboratory conditions,which serve to trigger electromagnetic valves(EMV)on the axial boom sprayer.A fuzzy logic algorithm was an integrated part of the intelligent system for controlling the PPP by generating the pulse width modulation signal and applying it through the EMV of the prototype boom sprayer.The results showed that by using an intelligent decision-making model,the same efficiency as with conventional methods could be achieved,but with reduced usage of plant protection products.Thus,the intelligent automated system used 4.8 times less spray mixture than the conventional one.
