Research On The Identification Of Mass For Heavy-Duty Vehicle Based On The Work-energy Principle

The transportation industry is the primary industry in the development ofnational economy, and highway transportation is one of the important components ofit. Nowadays Heavy-Duty Vehicle (HDV) plays an increasingly vital role inhighway transportation industry since it has some advantages such as low fuelconsumption, low transport costs, high economic benefit and so on. With thecontinuous development of heavy vehicle industry, the HDV’s dynamic performance,fuel economy and drivability have gradually become the issue of people’s concern.In order to improve these capabilities, the automatic transmission has been appliedto HDV. The automatic control issues of the automatic transmission need to besupported by obtaining the precise vehicle operation parameters. Due to the loadingsof the HDV is quite large and the difference between idle load and full load is alsoconsiderable, so the capture of the information of vehicle mass is particularlysignificant.On account of the features of work-energy principle, a new method aboutestimation of vehicle mass was presented in this thesis on the basis of a researchwhich has been proposed by Li Yuanfang who studied in Vehicle OperationSimulation Group of Jilin University. Some real-time and on-line results of vehiclemass which were estimated according to information derived from CAN can begained, and the results can be accepted. The main contents of the thesis are listed asfollows:Firstly, the vehicle’s longitudinal dynamics model was established. Byanalyzing the problems of the system and calculation errors which was generated inthe model calculation process, and considering the method of work-energy principlecan eliminate the sensitivity of this errors, then a vehicle dynamics model based onthe Work-energy Principle was established.Secondly, according to analysis that related to the property of vehicle massmentioned in Li Yuanfang’s thesis, the method of system identification which can estimate the HDV mass was still used. Then on the basis of some analysis of it, theTotal Least Squares method to estimate vehicle mass was proposed.Thirdly, the heavy-duty vehicle mass identification model on the basis of theWork-energy Principle and the Total Least Squares is built. And the program codesthat have been written by utilizing the compilation tools in the MATLAB andSimulink environment can live up to the function of the model. Then，singular valuedecomposition algorithm for the total least square method of the real-timeperformance is analyzed and improved.Finally, by using the flat and mountain road experimental database which havebeen established, the proposed model in this paper can be verified and analyzed. Thevehicle acceleration test on the flat road is carried out, and the result of the massestimation is in acceptable range, so the feasibility of the model has been validatedin this road condition. Then simulation experiment of four models, which have thefunction of vehicle mass estimation and are respectively built on the basis of theforce method and the Least Squares or the Total Least Squares and on the basis ofthe Work-energy Principle and the Least Squares or the Total Least Squares, isimplemented by using the flat road and mountain road test data. The result of massestimation of the four models are compared and analyzed, and a conclusion is drawnthat the result of the mass identification model based on the Work-energy Principleand the Total Least-Squares can olny meet the needs of the general project, but it canenhance the applicability of the model; and the accuracy of mass estimation can beimproved with the mass identification model based on the Work-energy Principleand the Least Squares.