Research On Dynamic Rollover Stability Of Articulated Engineering Vehicle

Articulated engineering vehicles, such as tractor, loader and excavator, have beenwidely used in engineering community including energy development, mining and roadbuilding. Its working environment is so poor and it has large loading mass. Meanwhile, itsfront and rear body are hinged together, which leads to poor lateral stability when steering.Articulated engineering vehicles rollover accident has occurred frequently in recent yearsand it caused severe casualties and economic loss. Therefore, the stability and security issuesof articulated engineering vehicle have been a hot spot among scholars at home and abroad.In order to ensure the driver’s life safety, international standard ISO3471requirementsthat the engineering vehicles should be installed rollover protection structure(ROPS)whichcan protect the driver in rollover accidents passively. But it cannot avoid vehicle rolloveressentially. So articulated engineering vehicles rollover stability mechanism needs to bestudied and active safety technology should be applied to avoid vehicle rollover. The presentresearch conducted by national research institution and scholars mostly focused on staticstability mechanism analysis while the technique of dynamic stability is inadequate. Thispaper aims to analyze the dynamic stability of articulated engineering vehicles. It issupported by the National Natural Science Foundation (NO.51175216), SpecializedResearch Fund for the Doctoral Program of Higher Education (NO.20100061110014) andGraduate Innovation Fund of Jilin University(No.20121081).Based on the latest findings athome and abroad, this paper firstly established a4-DOF degrees of freedom dynamic modelof articulated wheel loader. Then remote control loader model and vehicle rollover testplatform were designed to verify the dynamic model. Finally, dynamic rollover stability ofZL50loader wad analyzed.According to the above content, the paper explored the following discussions:1. The research background and significance of articulated engineering vehiclesrollover stability was systematically expounded and the present situation at home and abroadwas summarized. Then, the static lateral stability of loader when driving and steering onslope was analyzed from the first stability and the second stability. Moreover, several stability evaluation indexes were elaborated in detail and their advantage and disadvantageswere compared.2. Take the wheel loader as the research object, a4-DOF dynamic model wasestablished using Lagrangian method. This model was able to reflect most of thecharacteristics including lateral movement, yawing and rollover. The vehicle system’sdifferential equations of motion were solved by Matlab ode15i decoding instructions.3. This paper set up articulated engineering vehicle rollover test platform and designedthe remote control loader which was able to finish straight driving, steering and climbing.Driving and steering on the level road and slope was selected to verify the establisheddynamic model. The result showed that the model had higher precision.4. LTR (Lateral Load Transfer Ratio) was chosen to evaluate the vehicles rolloverstability. The driving and steering performance of ZL50wheel loader was simulated using4-DOF dynamic model and its dynamic rollover stability was analyzed when the vehiclesteered at different speed, different slope and different time period. Besides, the stable workarea of ZL50loader was obtained which laid a basic foundation for further study.The study of articulated engineering vehicle dynamic rollover stability is the basis ofdesign of active anti-rollover. Whether the research of vehicle rollover mechanism isthorough or not has direct effect on the accuracy and validity of anti-rollover control system.Therefore, this paper can provide certain basis for further study of articulated engineeringvehicle active safety technology.