Research On Field And Rapid Evaluation Technology Of Vehicle Handling And Stability Performance Test

The vehicle test plays an important role in the process of vehicle development and runs through the whole process of vehicle development.Whether a comprehensive performance evaluation of the standard car in the early stages of development,or type test after the prototype car is designed,or improved design of the new car after going into production,a large number of tests must be carried out.Due to the influence of the driver's subjective factors and lack of objective method for testing the validity of test data,invalid data is present.In the later process of test data,if invalid data is not found in time,it will lead to poor consistency and low credibilit y of the test results.If the invalid data are found and removed,the existing test data is not enough to support the analysis of vehicle performance,the new test needs to be carried out,which will waste a lot of manpower,material and financial resources,extend the development cycle of the automobile and reduce the market competitiveness of products.As one of the key factors that affects the active safety of the vehicle,handling and stabilit y not only affects the convenience of vehicle driving,but also decides the safety of high-speed cars.So this paper attempts to develop a field and rapid evaluation system of vehicle handling and stability tests.The research ideas are as follows: characteristic physical quantity of test scheme is identified through systematic analysis of vehicle handling and stability test scheme;a automatic and intelligent identification system for handling and stability tests and validit y checking system are established;an algorithm for automatic calculation of vehicle handling and stability indexes is developed.Specific research contents include the following aspects:Firstly,the vehicle handling and stability test scheme and characteristic physical quantit ie s are studied.A set of handling and stability test schemes which is relatively perfect and suitable for this study is established through the extensive investigation of the vehicle handling and stability test standards and the handling and stability test system of the major vehic le manufacturers.Characteristic physical quantities of test scheme are identified through the systematic analysis of vehicle handling and stability test scheme,which lays the foundation for intelligent identification of test scheme.Secondly,intelligent identification and validity test of vehicle handling stability test are studied.Under the same test scheme and different cases,the characteristic physical quantit ie s have the same order of magnitude and trend after data interpolation and standardization and the characteristic physical quantities of different test schemes have different trends.Based on the above two points,identification model of vehicle handling and stability test scheme is established through using the dynamic time warping method and neural network method in this paper.The layer by layer classification method is adopted to improve the recognition accuracy and reduce the recognition time.On this basis,the test condition parameters are extracted to identify the test condition,and the validity of the test is tested according to the standard test scheme and deviatio n requirements.The results show that the model established in this paper can not only identify the test scheme and test case with high efficiency and accuracy,but also can quickly verify the validity of the test data.Thirdly,automatic evaluation of vehicle handling stability test is studied.The objective evaluation index and evaluation index calculation algorithm of vehicle handling and stability are systematically integrated.Evaluation index calculation algorithm is implemented in the Matlab environment to realize the automatic calculation of evaluation indexes.Evaluation index calculation algorithm is verified by using the test data of a test car.The results show that the algorithm is stable and practical and can quickly and accurately calculate the vehicle handling and stability objective evaluation indexes.Finally,the application and verification of the rapid evaluation system of vehicle handling and stability test are studied.The vehicle handling and stability test scheme,characterist ic s physical quantity,the intelligent identification model of test,verification validity of the test and test evaluation are integrated together in the Matlab environment,then the rapid evaluat io n system of vehicle handling and stability test is formed.The validity and practicability of the system is verified by driving simulator test data and chassis parameters tuning process based on rapid evaluation technology of vehicle handling and stability.In this paper,the rapid evaluation system of vehicle handling and stability test based on the effective test data is realized,which increases consistency and reliability of test results,and provides technical support for reducing the test cycle,reducing the test cost and speeding up the process of vehicle development,as well as provides a theoretical basis for the chassis parameters tuning.