Heavy Duty Vehicle Control
Heavy Duty Vehicle Control Fuzzy-based anti-rollover controller for a heavy duty vehicle, using active suspension Andrés Riofrío*, Beatriz L. Boada, María Jesús L. Boada, Daniel García Pozuelo, Vicente Díaz Department of Mechanical Engineering, University of Carlos III Leganés, Madrid, 28911, Spain (ariofrio, bboada, mjboada, dgramos, vdiaz)@ing.uc3m.es
Keywords Rollover; Controller; Fuzzy Logic; Load Transfer; MATLAB; Simulink Research and/or Engineering Questions/Objective Nowadays, among the most common accidents in which heavy duty vehicles are involved, rollover is found to be the one which more often causes severe personal injuries. A controller has been developed for an anti - rollover system which uses active suspension. This system helps to reduce the load transfer between the sides of the vehicle, and therefore, to improve its dynamic behavior while cornering. Methodology The software TruckSim allows simulating the dynamic behavior of the vehicle. A model of a MercedesBenz Sprinter van has been used to carry out the simulations. This model has been validated by a real van equipped with sensors. TruckSim provides information about parameters as the roll angle or roll rate for each of the instances of the simulation. Using these data it is possible to determine a response for the set of actuators which compose the active suspension system. The response is determined by means of a program designed in MATLAB – SIMULINK by means of fuzzy logic. This response signal is sent automatically back to TruckSim. In order to find out the best set up for the system, a series of different tests in different environments are performed using the software TruckSim. These tests include from steering maneuvers in flat airfields to simulations at different speeds which replicate real driving conditions. Limitations of this study When using active suspension, the high weight of this type of vehicles affects negatively to behavior of the system. The higher the weight, the bigger the force needed to prevent rollover, and therefore, more complex and expensive actuators will be needed. The response time of the system will also be affected. Results In order to quantify the load transfer which is taking place in each moment, a load transfer coefficient has been defined. This coefficient takes values from -1 to +1, depending on the direction of the rollover. This coefficient, which varies for every instance of the simulation, has been used to compare the behavior of the vehicle using different configurations of the system. When the actuators act only in the rear axle of the vehicle it has been achieved a significant reduction of the load transfer, up to a 20%.
What does the paper offer that is new in the field including in comparison to other work by the authors? One of the strong points of the designed controller is its capability to work even when there is banking or inclination on the ground. This is possible as the criteria used to define the fuzzy logic rules changes automatically depending on the environment in which the van is being driven. In addition, this system works with an active suspension system equipped only in the rear part of the vehicle, which is simpler and cheaper than other configurations equipped both in the front and rear axles. Conclusions Fuzzy logic has shown to be a powerful tool to solve this strongly nonlinear problem, as with a few signals it has been possible to define a proper operation for the active suspension system. The obtained solution allows reducing load transfer and improving the dynamic behavior of the vehicle. Acknowledgments Authors gratefully acknowledge use of the services and facilities of the Research Institute of Vehicle Safety (ISVA) at Carlos III University, and the funds provided by the Spanish Government through the CICYT project TRA2013-48030-C2-1-R. *Corresponding author
Keywords Rollover; Controller; Fuzzy Logic; Load Transfer; MATLAB; Simulink Research and/or Engineering Questions/Objective Nowadays, among the most common accidents in which heavy duty vehicles are involved, rollover is found to be the one which more often causes severe personal injuries. A controller has been developed for an anti - rollover system which uses active suspension. This system helps to reduce the load transfer between the sides of the vehicle, and therefore, to improve its dynamic behavior while cornering. Methodology The software TruckSim allows simulating the dynamic behavior of the vehicle. A model of a MercedesBenz Sprinter van has been used to carry out the simulations. This model has been validated by a real van equipped with sensors. TruckSim provides information about parameters as the roll angle or roll rate for each of the instances of the simulation. Using these data it is possible to determine a response for the set of actuators which compose the active suspension system. The response is determined by means of a program designed in MATLAB – SIMULINK by means of fuzzy logic. This response signal is sent automatically back to TruckSim. In order to find out the best set up for the system, a series of different tests in different environments are performed using the software TruckSim. These tests include from steering maneuvers in flat airfields to simulations at different speeds which replicate real driving conditions. Limitations of this study When using active suspension, the high weight of this type of vehicles affects negatively to behavior of the system. The higher the weight, the bigger the force needed to prevent rollover, and therefore, more complex and expensive actuators will be needed. The response time of the system will also be affected. Results In order to quantify the load transfer which is taking place in each moment, a load transfer coefficient has been defined. This coefficient takes values from -1 to +1, depending on the direction of the rollover. This coefficient, which varies for every instance of the simulation, has been used to compare the behavior of the vehicle using different configurations of the system. When the actuators act only in the rear axle of the vehicle it has been achieved a significant reduction of the load transfer, up to a 20%.
What does the paper offer that is new in the field including in comparison to other work by the authors? One of the strong points of the designed controller is its capability to work even when there is banking or inclination on the ground. This is possible as the criteria used to define the fuzzy logic rules changes automatically depending on the environment in which the van is being driven. In addition, this system works with an active suspension system equipped only in the rear part of the vehicle, which is simpler and cheaper than other configurations equipped both in the front and rear axles. Conclusions Fuzzy logic has shown to be a powerful tool to solve this strongly nonlinear problem, as with a few signals it has been possible to define a proper operation for the active suspension system. The obtained solution allows reducing load transfer and improving the dynamic behavior of the vehicle. Acknowledgments Authors gratefully acknowledge use of the services and facilities of the Research Institute of Vehicle Safety (ISVA) at Carlos III University, and the funds provided by the Spanish Government through the CICYT project TRA2013-48030-C2-1-R. *Corresponding author
