Electrical system of military vehicle is a typical parameterized nonlinear system where complicated bifurcations may exist and threaten its safe and stable operation. An algebraic criterion for Hopf bifurcation is pre...Electrical system of military vehicle is a typical parameterized nonlinear system where complicated bifurcations may exist and threaten its safe and stable operation. An algebraic criterion for Hopf bifurcation is presented briefly and applied to find Hopf bifurcation point of the electrical system with automatic voltage regulator(AVR) dynamics in military vehicle. Hopf bifurcation controllers are designed for this electrical system by using wash-out filter,linear feedback,nonlinear feedback and their combination. The linear feedback control makes the system bring Hopf bifurcation at preferable parameter,the nonlinear feedback control modifies the type of the bifurcation,and the wash-out filter enhances the system damping,thus,the Hopf bifurcation is eliminated and the electrical system stability is ensured. Simulation results show the controller's validity.展开更多
Noise and whole-body vibration measurements were made in a Viking military vehicle to determine the variation that should be expected during repeat measures,the effect of speed(up to 60 km/h in 5 km/h increments),and ...Noise and whole-body vibration measurements were made in a Viking military vehicle to determine the variation that should be expected during repeat measures,the effect of speed(up to 60 km/h in 5 km/h increments),and during travel over different types of terrain(comprising concrete road,gravel track and rough cross-country).Measurements were made at various crew positions(including the driver and commander)in both the front and the rear cabs in the vehicles.Three translational axes of vibration were measured in each seat.Two speeds were investigated over road(35 km/h and 55e60 km/h)and gravel(20 km/h and 35 km/h)surfaces.The effect of varying speed of the vehicle on the measured noise and vibration magnitudes was also investigated.The highest sound pressure level(LAeq)of 104 dB(A)was measured at the commander’s standing position during travel over concrete road at 55 km/h.Higher noise levels occurred for a standing commander compared with when sitting on the seat.A maximum single axis frequency-weighted vibration magnitude of 1.0 m/s^(2) r.m.s.was measured on the driver’s seat during travel over track at 35 km/h.Higher vibration magnitudes occurred during travel over track compared with travel over road.Both noise and vibration exposure of crew within the Viking vehicle increased with increasing speed of the vehicle.展开更多
In the military parade held for celebrating the 50th anniversary of the People’s Republic of China, which attracted worldwide attention, 68 heavy military vehi-cles of SX2150 and SX2190 series towing heavy weapons in...In the military parade held for celebrating the 50th anniversary of the People’s Republic of China, which attracted worldwide attention, 68 heavy military vehi-cles of SX2150 and SX2190 series towing heavy weapons including missiles, etc., passed the Tian An Men square, making a show of force of Chinese defense equipment. These vehicles are produced by Shaanxi Au-展开更多
基金Sponsored by Foundation for Science Research Development of Nanjing University of Science and Technology
文摘Electrical system of military vehicle is a typical parameterized nonlinear system where complicated bifurcations may exist and threaten its safe and stable operation. An algebraic criterion for Hopf bifurcation is presented briefly and applied to find Hopf bifurcation point of the electrical system with automatic voltage regulator(AVR) dynamics in military vehicle. Hopf bifurcation controllers are designed for this electrical system by using wash-out filter,linear feedback,nonlinear feedback and their combination. The linear feedback control makes the system bring Hopf bifurcation at preferable parameter,the nonlinear feedback control modifies the type of the bifurcation,and the wash-out filter enhances the system damping,thus,the Hopf bifurcation is eliminated and the electrical system stability is ensured. Simulation results show the controller's validity.
文摘Noise and whole-body vibration measurements were made in a Viking military vehicle to determine the variation that should be expected during repeat measures,the effect of speed(up to 60 km/h in 5 km/h increments),and during travel over different types of terrain(comprising concrete road,gravel track and rough cross-country).Measurements were made at various crew positions(including the driver and commander)in both the front and the rear cabs in the vehicles.Three translational axes of vibration were measured in each seat.Two speeds were investigated over road(35 km/h and 55e60 km/h)and gravel(20 km/h and 35 km/h)surfaces.The effect of varying speed of the vehicle on the measured noise and vibration magnitudes was also investigated.The highest sound pressure level(LAeq)of 104 dB(A)was measured at the commander’s standing position during travel over concrete road at 55 km/h.Higher noise levels occurred for a standing commander compared with when sitting on the seat.A maximum single axis frequency-weighted vibration magnitude of 1.0 m/s^(2) r.m.s.was measured on the driver’s seat during travel over track at 35 km/h.Higher vibration magnitudes occurred during travel over track compared with travel over road.Both noise and vibration exposure of crew within the Viking vehicle increased with increasing speed of the vehicle.
基金supported by National Natural Science Foundation of China(61425008,61333004,61273054)Top-Notch Young Talents Program of China,and Aeronautical Foundation of China(2013585104)
基金supported by Foundation for Innovative Research Groups of National Natural Science Foundation of China(NSFC)(61321002)National Science Fund for Distinguished Young Scholars(60925011)+2 种基金Projects of Major International(Regional)Joint Research Program NSFC(61120106010)Beijing Education Committee Cooperation Building Foundation Project,Program for Changjiang Scholars and Innovative Research Team in University(IRT1208)Chang Jiang Scholars Program and National Natural Science Foundation of China(61203078)
文摘In the military parade held for celebrating the 50th anniversary of the People’s Republic of China, which attracted worldwide attention, 68 heavy military vehi-cles of SX2150 and SX2190 series towing heavy weapons including missiles, etc., passed the Tian An Men square, making a show of force of Chinese defense equipment. These vehicles are produced by Shaanxi Au-