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121.
对武广客运专线接触网安装中出现的负弛度现象进行了探讨和分析,总结出导致该现象的原因,并提出相应的改进建议。 相似文献
122.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(8):1225-1244
This paper presents a method to design a rollover prevention controller for vehicle systems. The vehicle rollover can be prevented by a controller that minimises the lateral acceleration and the roll angle. Rollover prevention capability can be enhanced if the controlled vehicle system is robust to the variation of the height of the centre of gravity and the speed of the vehicle. For this purpose, a robust controller is designed with linear matrix inequality-based trajectory sensitivity minimisation. Differential braking and active suspension are adopted as actuators that generate yaw and roll moments, respectively. The newly proposed method is shown to be effective in preventing rollover by the simulation on a non-linear multibody dynamic simulation software, CarSim®. 相似文献
123.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(10):1563-1584
A virtual test rig is presented using a three-dimensional model of the elasto-kinematic behaviour of a vehicle. A general approach is put forward to determine the three-dimensional position of the body and the main parameters which influence the handling of the vehicle. For the design process, the variable input data are the longitudinal and lateral acceleration and the curve radius, which are defined by the user as a design goal. For the optimisation process, once the vehicle has been built, the variable input data are the travel of the four struts and the steering wheel angle, which is obtained through monitoring the vehicle. The virtual test rig has been applied to a standard vehicle and the validity of the results has been proven. 相似文献
124.
正三轮摩托车方向把抖动是由于前转向系的不规则振动造成的,前轮的振动靠前减震器的阻尼来消除,因此前减震器的刚度及阻尼的匹配是一项非常重要的研究内容。 相似文献
125.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(5):305-331
This paper provides an overview of a theoretical study of an active seat suspension. The principal objective of this study is to improve ride passenger comfort by reducing transmitted seat acceleration. The seat is represented by a non-linear two degree of freedom model. The system is linearized for small perturbations around the equilibrium. To control the dynamic of the seat suspension, an original feedback control command with a reversible electromechanical actuator is achieved. The synthesis of the regulator is realized on the linearized model of the seat suspension and the root locus method is employed. Stability and robustness characteristics have been studied. Numerical simulations in time and frequency domain show the interests of the regulator and its capability to isolate seat passenger. 相似文献
126.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):507-528
In the first part of this study, the potential performance benefits of fluidically coupled passive suspensions were demonstrated through analyses of suspension properties, design flexibility and feasibility. In this second part of the study, the dynamic responses of a vehicle equipped with different configurations of fluidically coupled hydro-pneumatic suspension systems are investigated for more comprehensive assessments of the coupled suspension concepts. A generalised 14 degree-of-freedom nonlinear vehicle model is developed and validated to evaluate vehicle ride and handling dynamic responses and suspension anti-roll and anti-pitch characteristics under various road excitations and steering/braking manoeuvres. The dynamic responses of the vehicle model with the coupled suspension are compared with those of the unconnected suspensions to demonstrate the performance potential of the fluidic couplings. The dynamic responses together with the suspension properties suggest that the full-vehicle-coupled hydro-pneumatic suspension could offer considerable potential in realising enhanced ride and handling performance, as well as improved anti-roll and anti-pitch properties in a very flexible and energy-saving manner. 相似文献
127.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(11):795-806
Two typical criteria for good vehicle suspension performance are their ability to provide good road handling and increased passenger comfort. The main disturbance affecting these two criteria is terrain irregularities. Active suspension control systems reduce these undesirable effects by isolating car body motion from vibrations at the wheels. This paper describes fuzzy and adaptive fuzzy control (AFC) schemes for the automobile active suspension system (ASS). The design objective is to provide smooth vertical motion so as to achieve the road holding and riding comfort over a wide range of road profiles. The efficacy of the proposed control schemes is demonstrated via simulations. With respect to the optimal linear quadratic regulator (LQR), it is shown that superior results have been achieved by the AFC. 相似文献
128.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(4):457-464
The quarter car model has been used extensively to study the benefits of active, semi-active and passive suspensions. Despite the evident simplicity of the model, the insights obtained from this model have been found to have counterparts in half- and full-car suspension models. Among the most interesting results of the analysis of the quarter car are the relationships among certain transfer function and invariant points in the frequency response functions. These results are of great interest for the application of linear control techniques to the design of active suspensions and the optimisation of linearised passive suspensions. This paper attempts to show why some of the limitations implied by the model are less absolute than they at first seem. 相似文献
129.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(7):575-595
This paper discusses the nonlinear properties of inerters and their impact on vehicle suspension control. The inerter was recently introduced as an ideal mechanical two-terminal element, which is a substitute for the mass element, where the applied force is proportional to the relative acceleration across the terminals. Until now, ideal inerters have been applied to vehicle, motorcycle and train suspension systems, in which significant performance improvement was achieved. However, due to the mechanical construction, some nonlinear properties of the existing mechanical models of inerters are noted. This paper investigates the inerter nonlinearities, including friction, backlash and the elastic effect, and their influence on vehicle suspension performance. A testing platform is also built to verify the nonlinear properties of the inerter model. 相似文献
130.
直线电机地铁车辆转向架 总被引:2,自引:0,他引:2
介绍了直线电机地铁车辆转向架的功能和组成、径向转向架的采用、直线感应电机悬挂技术、直线感应电机气隙调节装置,最后提出了目前直线电机地铁车辆转向架设计建议。 相似文献