【摘要】 齿条力是线控转向系统路感设计和转向跟随控制中的关键参数，但是由于其在量产车中难以被直接测量，因此，对其观测成为线控转向中的一个关键环节。采用两种方法观测齿条力，一种是基于车辆动力学的观测方法，采用龙伯格观测器观测车辆侧向速度，并结合轮胎刷子模型分析转向阻力矩；另一种是基于转向动力学的观测方法，通过建立转向执行机构动力学模型，并采用卡尔曼滤波实现对齿条力的直接观测。在此基础上，通过硬件在环台架试验比较两种方法的齿条力观测效果，提出基于多变量的规则式融合策略对两种方法进行优势互补。通过台架试验验证所提出的融合策略能在不同工况下有效提高齿条力观测的准确性和实时性。更多还原

【Abstract】 Rack force is a critical parameter in road feel design and steering follow-up control for steer-bywire systems. Since it is difficult to measure rack force directly in mass-produced vehicles, its estimation becomes a key aspect in steer-by-wire. This article adopts two methods to estimate the rack force. The first method is based on vehicle dynamics, using Luenberger observer to obtain lateral velocity and the tire brush model is applied to analyze steering resistance torque. The second method is based on steering dynamics,involving a dynamic model for the steering actuator and the direct estimation of rack force using a Kalman filter. The results of the two methods are compared through hardware-in-the-loop(HIL) testing, and then a rule-based fusion strategy using multiple variables is proposed to combine the strengths of the two methods.Finally, bench test results show that the proposed fusion strategy effectively improves the accuracy and realtime performance of rack force estimation under different working conditions.更多还原