The design,modeling,and simulation of a micro electrical switch for fuze are presented.It consists of springemass system with zigzag slot in mass,latching and electrical connection mechanism and movement-limit mechani...The design,modeling,and simulation of a micro electrical switch for fuze are presented.It consists of springemass system with zigzag slot in mass,latching and electrical connection mechanism and movement-limit mechanism.The switch keeps off-state until it is subjected to an acceleration when fuze is launched normally.The acceleration is simulated as half-sine pulse with specific amplitude and duration.The dynamics model of the switch is studied.Based on zigzag slot in mass,the methods used for recognizing acceleration load are established and analyzed according to the dynamics theory.Two typical half-sine accelerations are loaded on the switch in simulation.The simulation results are in accordance with those of theoretical analysis.The inertial response characteristics of the switch can ensure that the fuze power supply and circuit are connected safely and reliably.展开更多
The squeeze-film air damping exists in a lot of micro-electronic-mechanical system (MEMS) devices unavoidably. The effects of air damping in traditional inertial switch with spring-mass system can be ignored for its l...The squeeze-film air damping exists in a lot of micro-electronic-mechanical system (MEMS) devices unavoidably. The effects of air damping in traditional inertial switch with spring-mass system can be ignored for its large volume and mass. But, many properties of MEMS switch, such as sensitivity, resolution and contact time, are affected by the air damping caused from the squeezed air film between two parallel plates moving relatively. Based on the conservation laws for mass and flux and the nonlinear Reynolds equation, the coefficient of squeeze-film damping was derived. The dynamic responses of the inertial switch with and without squeeze-film damping were simulated by using software ANSYS. The simulated results show that the sensitivity and contact time of the switch descend by about 5% and 15%, respectively, when the effects of squeeze-film damping are considered.展开更多
In this paper,we investigate an inertial two-neural coupling system with multiple delays.We analyze the number of equilibrium points and demonstrate the corresponding pitchfork bifurcation.Results show that the system...In this paper,we investigate an inertial two-neural coupling system with multiple delays.We analyze the number of equilibrium points and demonstrate the corresponding pitchfork bifurcation.Results show that the system has a unique equilibrium as well as three equilibria for different values of coupling weights.The local asymptotic stability of the equilibrium point is studied using the corresponding characteristic equation.We find that multiple delays can induce the system to exhibit stable switching between the resting state and periodic motion.Stability regions with delay-dependence are exhibited in the parameter plane of the time delays employing the Hopf bifurcation curves.To obtain the global perspective of the system dynamics,stability and periodic activity involving multiple equilibria are investigated by analyzing the intersection points of the pitchfork and Hopf bifurcation curves,called the Bogdanov-Takens(BT)bifurcation.The homoclinic bifurcation and the fold bifurcation of limit cycle are obtained using the BT theoretical results of the third-order normal form.Finally,numerical simulations are provided to support the theoretical analyses.展开更多
文摘The design,modeling,and simulation of a micro electrical switch for fuze are presented.It consists of springemass system with zigzag slot in mass,latching and electrical connection mechanism and movement-limit mechanism.The switch keeps off-state until it is subjected to an acceleration when fuze is launched normally.The acceleration is simulated as half-sine pulse with specific amplitude and duration.The dynamics model of the switch is studied.Based on zigzag slot in mass,the methods used for recognizing acceleration load are established and analyzed according to the dynamics theory.Two typical half-sine accelerations are loaded on the switch in simulation.The simulation results are in accordance with those of theoretical analysis.The inertial response characteristics of the switch can ensure that the fuze power supply and circuit are connected safely and reliably.
文摘The squeeze-film air damping exists in a lot of micro-electronic-mechanical system (MEMS) devices unavoidably. The effects of air damping in traditional inertial switch with spring-mass system can be ignored for its large volume and mass. But, many properties of MEMS switch, such as sensitivity, resolution and contact time, are affected by the air damping caused from the squeezed air film between two parallel plates moving relatively. Based on the conservation laws for mass and flux and the nonlinear Reynolds equation, the coefficient of squeeze-film damping was derived. The dynamic responses of the inertial switch with and without squeeze-film damping were simulated by using software ANSYS. The simulated results show that the sensitivity and contact time of the switch descend by about 5% and 15%, respectively, when the effects of squeeze-film damping are considered.
基金supported by the National Natural Science Foundation of China(Grant No.11302126)the State Key Program of National Natural Science of China(Grant No.11032009)+1 种基金the Shanghai Leading Academic Discipline Project(Grant No.B302)Young Teacher Training Program of Colleges and Universities in Shanghai(Grant No.ZZhy12030)
文摘In this paper,we investigate an inertial two-neural coupling system with multiple delays.We analyze the number of equilibrium points and demonstrate the corresponding pitchfork bifurcation.Results show that the system has a unique equilibrium as well as three equilibria for different values of coupling weights.The local asymptotic stability of the equilibrium point is studied using the corresponding characteristic equation.We find that multiple delays can induce the system to exhibit stable switching between the resting state and periodic motion.Stability regions with delay-dependence are exhibited in the parameter plane of the time delays employing the Hopf bifurcation curves.To obtain the global perspective of the system dynamics,stability and periodic activity involving multiple equilibria are investigated by analyzing the intersection points of the pitchfork and Hopf bifurcation curves,called the Bogdanov-Takens(BT)bifurcation.The homoclinic bifurcation and the fold bifurcation of limit cycle are obtained using the BT theoretical results of the third-order normal form.Finally,numerical simulations are provided to support the theoretical analyses.