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线控转向系统力反馈的研究 总被引:1,自引:0,他引:1
线控转向系统取消了转向盘与转向轮的机械连接,所以必须通过电机向驾驶员实时反馈路感,从而使驾驶员感知车辆行驶状态和路面状况.首先建立了包括驾驶员在内的转向盘力反馈模型.提出的路感控制策略包括上层控制策略和下层控制策略.上层控制策略中转向盘回正力矩建模为扭杆弹簧施加的回复力矩,与转向盘转角成线性;下层控制策略对电机电流进行比例积分控制.最后研究了不同驾驶员模型比例系数,积分系数和电流比例积分控制的比例系数,积分系数对转向盘转角跟踪性能的影响.结果表明,遗传算法优化得到的这四个参数,可使得驾驶员较好跟踪转向盘转角,路感电机电流较好跟踪目标电流,实现较好的力反馈. 相似文献
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《Mechatronics》2022
This paper proposes an event-triggered higher-order sliding mode control for steer-by-wire (SbW) systems subject to limited communication resources and uncertain nonlinearity. First, an interval type-2 fuzzy logic system (IT2 FLS) is adopted to approximate the uncertain nonlinearities. A fuzzy-based state observer is developed to estimate unavailable states of the extended SbW system. Then, to save communication resources and eliminate chattering, an event-triggered higher-order sliding mode control is proposed for the SbW system. The key advantage is that the proposed control scheme can offset the observation error and the event-triggering error. After that, the practical finite-time stability of the closed-loop SbW system is proved in the framework of the Lyapunov theory. Finally, numerical simulations and vehicle experiments are given to evaluate the effectiveness and superiority of the proposed scheme. 相似文献
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Steer-by-wire technologies remain under rigorous research and development given the advantages that they offer over their traditional counterparts. The spectrum of steering systems encompasses applications in the automotive, construction, agricultural, and aerospace industries, to name a few.An original electro-hydraulic steer-by-wire technology based on pump displacement control actuation, an energy efficient alternative to conventional valve control, has been previously proposed by the authors. The new concept was validated and implemented on an articulated steering prototype test vehicle, and resulted in significant fuel savings and machine efficiency increase. This paper investigates the notion of virtual sensing relative to estimating the vehicle׳s yaw rate by only measuring the articulation angle and vehicle speed. Virtual sensing is a promising concept for yaw stability control and is an attractive option for vehicle manufactures as it reduces sensor cost, maintenance, and machine downtime. The designed yaw rate sensor is validated in simulation as well as on a test vehicle by devising appropriate steering maneuvers. 相似文献
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Gearboxes allow for changes in the motor’s torque and speed ranges, thus allowing the motor to function at its best operation ranges. As a consequence, smaller and low cost motors can be used in comparison with direct drive motors. Nevertheless, gearboxes introduce nonlinearities to the system such as friction, backlash and flexibility. When geared motors are employed, a controller using a torque sensor or a torque observer is normally required to compensate for the drawbacks associated with the gearbox and the servo-amplifier. The design of such a controller requires the comprehensive knowledge of the system’s dynamics. In this paper, a general approach to model accurately amplifier–motor–gearbox assemblies has been developed. This approach that takes into account backlash, flexibility, friction for stiction and sliding, identification procedures, is applicable to a wide range of amplifier–motor–gearbox assemblies. It is explained by applying it to a particular case: an amplifier–motor–gearbox assembly for a driver’s force feedback system. In the design of driver’s force feedback systems for steer-by-wire systems or for high fidelity Human in the Loop (HiL) driving simulators, either direct drive motors or geared motors are used, independently of the motor type. The assembly considered here is composed of a two stage planetary gearbox, a coreless PMDC motor and a linear four quadrant servo-amplifier. It is installed in an X-by-wire (XBW) vehicle prototype, Both the amplifier and the mechanical components were built in the model. The four quadrant operating modes of the amplifier were taken into account. Friction within both the motor and the gearbox are modelled using a modification of the LuGre friction model that allows friction to be considered as load-dependent. Backlash and flexibility in the gearbox are considered together using a fifth order polynomial for each rotational direction. The identification procedures necessary to calculate the parameters of the model are presented. Because all the parameters of the model have a direct physical significance, these identification procedures are easy to realize. Comparisons between simulations realized with Simulink and the experimental data for three typical driving situations show that the model is highly accurate at representing real system dynamics. 相似文献
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Ryouhei Hayama Masayasu Higashi Sadahiro Kawahara Shirou Nakano Hiromitsu Kumamoto 《Reliability Engineering & System Safety》2010,95(1):10-17
Steer-by-wire (SBW) systems, which have no mechanical linkage between the steering wheel and front wheels, are expected to improve vehicle safety through better steering capability. SBW system failures, however, can cause hazardous driving situations. This paper introduces fault-tolerant architecture based on diversified steering mechanisms consisting of SBW backed up with steering by braking and acceleration during SBW failures. These backup steering functions are chosen according to driver's intention of deceleration and acceleration. A loss of SBW function during front-obstacle avoidance on a straight highway is investigated by driving simulator experiments. The results show that the driver can maneuver the vehicle by the steering wheel during the SBW failures. Both cost and volume increase by excessive redundancy within SBW is avoided by the diversified design, thus facilitating SBW application on new-generation vehicles. 相似文献
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针对车辆线控转向系统(steer by wire,SBW),提出了一种基于系统模型的瞬时故障层次化容错控制方法,用于提高线控转向控制的可靠性。首先分析了SBW系统结构特点和工作原理,然后给出了SBW系统的系统模型,提出了瞬时故障容锚控制框架,详细设计了SBW系统节点级和系统级的瞬时故障容错控制机制,最后利用AADL(Architecture Analysis and Design Language)-Ocarina搭建了SBW仿真系统,对提出的容错方法进行仿真验证。仿真结果表明,本文提出的层次化容错控制方法能够有效地检测SBW系统瞬时故障,实现容错控制,提高系统运行可靠性。 相似文献
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