【作者】 张建国；

【导师】 李显生；

【作者基本信息】 吉林大学 ， 交通环境与安全技术， 2010， 博士

【摘要】 随着半挂汽车列车保有量的逐年增加,半挂汽车列车运输的日益普及,与半挂汽车列车相关的交通事故也逐渐增加。半挂汽车列车运输暴露出的安全性问题越来越受到人们的重视。考虑驾驶员对车辆行驶稳定性影响的半挂汽车列车闭环系统行驶稳定性研究,是半挂汽车列车行驶稳定性研究的一个非常重要的研究方向,对提高半挂汽车列车的行驶安全性有重要意义。本文建立了半挂汽车列车非线性九自由度数学模型和线性五自由度数学模型。根据研究需要,将模型进一步简化成线性三自由度半挂汽车列车模型。将该车辆模型与具有时间延迟的驾驶员模型耦合成半挂汽车列车—驾驶员闭环系统,采用准牛顿最优算法确定了驾驶员模型参数。以半挂汽车列车—驾驶员闭环系统模型为研究对象,分析了驾驶员反应延迟、车辆载重、车速对半挂汽车列车的直线行驶稳定性的影响。采用一种数值算法分析了闭环系统的临界车速,还在频域内对半挂汽车列车—驾驶员闭环系统特性进行了分析。通过两种半挂汽车列车转向行驶控制策略,即有制动转向控制策略和无制动转向控制策略,研究了半挂汽车列车的弯道行驶稳定性。在有制动转向控制策略中将牵引车前轮转向角和系统制动力作为输入量控制车辆行驶状态,采用多变量反推法设计了方向与制动联合控制策略。采用TruckSim和ADAMS软件分别建立了半挂汽车列车—驾驶员闭环系统模型,应用两种软件所建模型分别分析了半挂汽车列车的直线行驶稳定性和弯道行驶稳定性。验证了本文所建半挂汽车列车—驾驶员闭环系统模型的有效性和分析的正确性。更多还原

【Abstract】 With the rapid development of road transportation,at the background of the energy crisis and the global economic recession, when the "green transportation"、"low-carbon transport" putted forward by the government, road transportation are developing in the direction towards high efficiency and intensification. Developing trends of transport vehicles is bound to high-speed, professional and heavy-duty. As the number of tractor-semitrailer is increasing year by year, the traffic accidents caused by tractor-semitrailers are also increasing rapidly. The loss caused by the accidents is more and more serious. The security issue of tractor-semitrailer transportation is highly important and got more and more attention.As the structure is relatively complex, tractor-semitrailer’s driving stability is poor. So the "roll", "jack-knifing", " yawing" and "swing" and other dangerous operating conditions easily happen and result in traffic accidents. Therefore, the tractor-semitrailer’s traffic safety study has great significance. Tractor-semitrailer’s driving safety is not only relate to the vehicle’s own characteristics and traffic environment, but also relate to the driver’s control. Most previous studies just focused on the characteristics of the vehicle itself, the role of the driver is few take into account. In the study field of tractor-semitrailer stability, taking the driver’s impact into account, the study of tractor-semitrailer closed-loop system stability is a very important research direction. Study result in this area will greatly enhance the tractor-semitrailer’s driving safety and give a solution to improve tractor-semitrailer’s driving safety. Around the tractor-semitrailer’s driving stability of the closed-loop system, this paper carried out the following work:First of all, the approaches of modeling tractor-semitrailer dynamics were comprehensive analyze and the main degrees of freedom and parameters of tractor-semitrailer were tackled. According to research needs, the system was simplify reasonably and non-linear 9-DOF and linear 5-DOF tractor-semitrailer mathematical model were established respectively. This work offered a good tool for analysis of driving stability of tractor-semitrailers.In order to study driving stability of the tractor-semitrailers more real and more effective and improve the tractor-semitrailer’s driving safety, a tractor-semitrailer closed-loop system is established in this paper. The system model couple the dirver modeling with time-delay and linear 3-DOF tractor-semitrailer model. Quasi-Newton algorithm was used to determine the optimal parameters of the driver model.Closed-loop system tractor-semitrailer was used to study the driver’s response delay time, vehicle’s load and speed’s impact on straight driving stability of the tractor-semitrailer. A numerical algorithm is used for analysis the system’s critical speed and the characteristics of the system in frequency domain range. The results show that: suitable load, appropriate travel speed and driver’s good mental state can significantly improve the driving stability the driving safety of tractor-semitrailer.Taking closed-loop system model of tractor-semitrailer as the research object, two kinds of tractor-semitrailer steering control strategy, braking and steering control strategy and non-braking steering control strategy were used to study the driving stability of tractor-semitrailer driving on the bending road. In the braking and steering control strategy, the front wheel steering angle and system braking force were used as control input to control vehicle’s motion state. The multivariable backstepping design method was utilized to braking and steering control strategy. The results show that the braking and steering control strategy can more effectively reduce the tractor and the trailer’s yawing angle error and increase the stability of the vehicle.In order to verify the correctness of the models and the rationality of analysis in this paper, tractor-semitrailer model was established by TruckSim and ADAMS software respectively. Using the models established by two kinds of software, we analyzed the system’s straight driving stability and cornering stability. The results are in well agreement with the result from this paper’s model. This confirms that the model established in thia paper is right and the result is reasonable. In addition, the reasons why the software models’ analysis results and the calculation results have little differences were also analyzed.更多还原