Study On The Novel Mode Of Vehicle Operating Safe State Monitoring

The active novel mode of vehicle operating safe state monitoring will be the inevitabletrend of vehicle driving safety measurement technology development in the future. The thesis"Study on the novel mode of vehicle operating safe state monitoring" systematically studiesfundamental theory&key technology&realize method of vehicle operating safe statemonitoring system, including vehicle operating attitude monitoring model, vehicle dynamicload monitoring model, vehicle braking performance monitoring model, which has importantacademic value and practical significance in improving the technical protection of vehiclesafe operation, reducing traffic accidents and promoting the development of automobileindustry and Instrument Science and Technology. This paper was supported by the Programfor New Century Excellent Talents in University of Ministry of Education(No.NCET-08-0211),Guangdong province Science and Technology Researching Project (No.20090119) and Natural science Foundation of china (No.60472006).This paper analysed the research status in vehicle operating safe state monitoring athome and abroad and suggested that the vehicle monitoring parameters are few, which cannotreflect the requirement of vehicle operating safe state monitoring truly and dynamically andget information be used comprehensively and effectively, then made the research scheme.Main works:⑴An index system in novel monitoring mode and the whole structure of the monitoringmode were put forward. The novel monitoring mode index system include monitoringvehicle's three key parameters: motion attitude parameter(MAP), dynamic load parameter(DLP) and braking performance parameter(BPP).By establishing the connection among MAP,DLP and BPP information, some parameters that other traditional systems cannot measure canbe obtained; With the27-parameter information in novel monitoring mode, vehicle operatingsafe state can be reflected truly and dynamically, which is more comprehensive and scientificthan ever. Proposed the structure of motor vehicle operating safe state monitoring platformand the over-all structure of vehicular information perception and control terminal; analysedthe functional requirement of monitoring system from three function levels of the informationperception, information transmission and application development; and discussed the ideason how to realize key monitoring models such as wheel MAP, wheel DLP, wheel BPP andso on; to lay foundation for deep research into the model project(program).⑵The monitoring technology of motor vehicle MAP was studied systematically anddeeply. GFSIMU scheme were proposed based on the3d acceleration sensor cube to configurate12-acceleration components, the mathematical modes of body attitude angleB, B, B, velocity v Bx, v By,v Bz and acceleration a Bx, a By,a Bz were deduced and then tohave the motor vehicle body MAP inertia be measured. Wheel MAP accelerometer schemewere proposed, and mathematical models of the wheel i(i=1~4) attitude angle i, i, i, thewheel hub acceleration aS Ti, aS Si,aS Ci, the wheel hub velocity vS Ti, vS Si,vS Ci, and therotating parameter were deduced and then to have the wheel MAP inertia be measured.Basing on the characteristic of the wheel hub's shape, a circular triangle mobile hub controlplate was designed to install wheel sensor module, which is convenient to perform the test andalso of no impact on the principle and method of experiment. The output signal of tangentialacceleration sensor with better SNR is proposed to be chosen as the suitable feature variableof wheel signal, which could correct past practice that choosing centripetal acceleration sensoroutput signal. MAP monitoring program has the characteristics of less actual accelerationsensor, simple algorithm, easy to solve and high accuracy.⑶The novel monitoring scheme and principle for dynamic loadLi and the brakingforceFb iwas studied systematically. The monitoring scheme of dynamic loadLi is based onthe fact that wheel dynamic loadLi varies with the axle load's transfer, road's smoothnessand the ground counter-force's influence, then deduced the mathematical computationalformula of wheel dynamic loadLi. The monitoring scheme of braking forceFb iis based onthe variation of wheel BPP's wheel slip rateS i, braking forceFb iand balance parametersduring driving process of the motor vehicle, then deduced the wheel braking forceFb iand itsbalanced mathematical expression. Compared to other methods, this one's installation is easyand its arithmetic is simple, as well, it could reflect the wheel braking information real-time,truly and dynamically.⑷The algorithm of vehicle body angular velocity attitude Angle was studied basing onneural network. While the model is not clear, the method is more complex, the neural networkmodel was used to replace the original model based on mechanism, so as to improve theaccuracy and reduce the algorithm error. The neural network splitting method was proposedbasing on the typical road-condition wheel body angular velocity to consider the number ofneurons, training sample numbers and training function factors in hidden layer. The researchbased on orthogonal design network structure optimization methods and designed the statesorter which could recognize the corresponding motion state, so as to make corresponding data smoothly enter the sub-neural network to calculate.⑸Research, development and experiment of the vehicles driving safe testing systemand monitoring experimental platform were carried out. The wheel intelligence sensor nodescombined biaxial acceleration sensors and monaxial acceleration sensors to form multiplemeasurement instruments. By placing two measuring sensors in two sides of the circuit board,three acceleration sensitive axis were intersected to one point. Based on WEB to research anddevelop the vehicles' GPS location parameters monitoring device, develop the monitoringplatform remote management system, including remote data server, SQL database, monitoringplatform remote management software. Take advantage of the experimental conditions tomake out test method. Through experiment verification, the monitoring system and platformcould accurately detect all the monitoring parameters of vehicles operating safe state, andrealize the remote online monitoring function.⑹Based on WEIS other development application solutions of the vehicle operating safestate monitoring platform technology was proposed. The safe state rapid detection system thatbased on the wheel load type intelligent sensor WEIS can save space and have the fielddetection, its testing ability was1times above than traditional fixed detection line. Thefour-wheel location parameter measurement system that based on the wheel load typeintelligent sensor WEIS could provide rapid, dynamic, accurate and true detection forfour-wheel location parameters on the site. Based on the wheel load type intelligent sensorWEIS, the dynamic balance parameter measuring system could provide rapid, dynamic andaccurate detection for wheel dynamic balance parameter.The experiments show that, the body longitudinal attitude θBaverage error is0.0690o,thebody side-inclination angle ФBaverage error is0.0351o,the body forward direction velocityνBxaverage error is1.3607m/s, the wheel extraversion γiaverage error is0.0734°,the wheeltangential velocity νStiaverage error is0.1480m/s,the wheel angular velocity ωiaverage erroris0.5420rad/s, relative error is2.25%under the experimental conditions.the novel monitoringmodel on this paper was feasible, the sensor configuration scheme was correct, and themonitoring parameters were comprehensive which could detect all27of state monitoringparameters to reach the expected effect, with important promotional value.