Design Of Concrete Mixer Truck Model Used For Anti-rollover Controlling Test And Study Of Control Algorithm

With a rather high centroid, yet a narrow distance between wheels relative to the frame of the concrete mixer, and the concrete stirred in its canister in transit, dragging the center of gravity accordingly, the mixer's center of gravity is therefore offset from its longitudinal axis. In addition, the concrete mixer is one of the urban transport vehicles, which have to turn, to keep away from the pedestrians and other vehicles for most of the time. The structure and the characteristics of driving the mixer mentioned above make side-rollover accidents easy to occur. The research on preventing the side-rollover accidents of heavy trucks, tractor-semitrailers, SUVs and ordinary vehicles has been mature. However, because of the peculiarity that the centroid of the mixer changes as the concrete in the canister being stirred, there is no research yet on the controlling system of preventing side-rollover accidents of the concrete mixer in China. Therefore, the research on this aspect possesses the important practical significance. This paper takes the 8m3 wet type concrete mixer as the research object, applying the model test and the similarity theories in order to find similar conditions of the real mixer and the model in the side-rollover accident. And the design parameters for model mixer is obtained through transformation of the real one. By using CATIA, AUTOCAD software and the relevant automobile design theories, the physical model of the concrete mixer is designed according to the relevant design parameters mentioned above. And it is then processed and equipped for later tests of preventing side-rollover accidents. Based on the analysis of the action of turning of the model mixer, especially on the influence of centroid of the whole vehicle made by the stirring of the canister in the process of veering, the three degrees of freedom dynamics model of concrete mixer is established. By employing the strategy of double closed-loop control system based on the active front steering and brake of the rear steering, the method of preventing side-rollover is designed. And the dynamics simulation model as well as the model of controller are set up under Matlab/Simulink environment. With both models, the method of preventing side-rollover is tested and evaluated. The simulation results show that the control method can effectively prevent concrete mixer from side–rollover to a certain degree.