Development And Simulation Of Two Kinds Suspension Model For Heavy-duty Truck

With the continuous changes of market,reinforcement of steps carried out to protect environment,the increase of added value for cargos,improvement of the expressway network,rise of new style road logistics industry,high-quality heavy-duty trucks will soon occupy a major share of the internal heavy-duty truck market.At present,heavy-duty trucks of self-owned brand possessed over 90 percent of the market,but the trucks of self-owned brand can not reach the future national standard such as fuel economy,exhaust emission technology and security of cabs,and has large disadvantages in the area as products quality and technical level contrasted with international advanced heavy-duty truck products. With the accomplishment of the tariff reduction of imported automobiles for the third time at year 2006 since our nation's WTO accession,foreign enterprises of heavy-duty trucks enhanced their input of products and capital,and strengthened the power to joint venture.Under such circumstances,how to absorb the advanced technology,enhance our power of heavy-duty trucks research,development and innovation independently,improve the R&D system of heavy-duty trucks became a challenge which our automobile enterprises must face.The main characteristic of Virtual prototype technology which as a branch of CAE (Computer Aided Education) is considered to be able to analyze over the system level.By using this technology the process of design and development for automobile can be simplified,the product development cycle can be shorten,the costs of development can be reduced,product quality and performance at the system level can be improved,the most optimized designed products can be obtained in the end.This thesis is for the purpose of studying the modeling of heavy-duty trucks suspension using Virtual prototype technology and its corresponding software ADAMS.(1) In Chapter One,first of all,the status quo of internal trucks market was analyzed,which predicted that heavy-duty trucks inevitably become a dominant power in the trucks market from the objective data and trend of development,but currently our heavy-duty truck enterprises is unable to compete with foreign counterparts in developing and manufacturing, so our automobile enterprise are inevitably in the face of big challenge.And then the concept and base of establishment for Virtual Prototype Technology and its representative software ADAMS were introduced briefly,the using of Virtual Prototype Technology at home and abroad especially in the field of manufacturing automobile were contrasted.Finally,the main contents of the thesis were put forward. (2) In Chapter Two,the basic principle of main leaf spring modeling methods home and abroad were introduced,advantages and disadvantages of these methods were summarized and analyzed.ADAMS/Car Leaf Spring module which based on the finite element modal method was introduced,the modeling principle of leaf spring module was analyzed,and the step of modeling and parameters were explained in detail.A leaf spring template containing two leaves was built using ADAMS/Car Leaf Spring module in order to carry on a modeling demonstration.To validate the model necessary modification were made to measure vertical stiffness of the spring,which should be used to compare with the stiffness of actual leaf spring,big difference should lead to rebuilding the model.(3) In Chapter Three,software TruckSim was introduced briefly at the beginning,and then dependent suspension modeling in the whole vehicle model of TruckSim was described in detail,the kinematics and compliance parameters of suspension were listed in the form of tabulation.In order to be close to actual situation,a leaf spring template containing seven leaves was built by using ADAMS/Car Leaf Spring module,which was then used to build a leaf spring subsystem,the subsystem assembled into a heavy-duty truck steering axle(front axle) and a driving axle(rear axle) suspension dynamic model respectively,according to the need of kinematics and compliance parameters used in the TruckSim dependent suspension modeling,suspension kinematics and compliance simulation were carried out,and the data obtained or calculated from simulation were theoretical analyzed.(4) In Chapter Four,the origin and development process of balanced suspension were introduced,the species used in existing balanced suspension were summed up.Concrete structure and installation measurements of guide rod balanced suspension were illustrated in detail.The suspension mentioned above was divided into rigid parts and flexible parts of two major parts by analyzing and simplifying the structure.Firstly,the rigid parts model were built,secondly,the flexible parts—the leaf spring balanced arm model were built using beam element,and the vertical stiffness of balance arm was tested as well.A integrated guide rod balanced suspension dynamic model was assembled by reasonably constraint the leaf spring balanced arm with axle assembly and mandrel assembly.In order to validate the reasonability of model structure,four vertical displacement motion actuator were applied in the ends of axle to simulate parallel wheel travel,pitch,roll and pitch-roll conditions of the balanced suspension,the track of the suspension was observed to validate the reasonability of model structure.The main significance of this thesis research work is as follows: (1) According to the need of kinematics and compliance parameters used in the TruckSim dependent suspension modeling,relevant simulation for heavy-duty truck front axle(steering axle) and rear axle(driving axle)suspension were carried out.Not only solve the problem caused by difficulty to gain the parameter used in modeling suspension in TruckSim due to that which is hard to make a test-bed experiment for heavy-duty truck,but also build the foundation for next step work as modeling the whole vehicle,progressing model simulation and making vehicle performance evaluation.(2) Based on the guide rod balanced suspension's actual structure,a research for suspension dynamic model has progressed.The establishment of the model can be a virtual structure support in two kinds of modeling balanced suspension,modeling parameter can be obtained through progressing virtual simulation.One is the modeling balanced suspension in TruckSim,the other is simplifying balanced suspension in ADAMS/Car.