ITESMModels Active Suspension with Adams and MATLAB Simulink

ITESM Monterrey Campus Models Active Suspension with Adams and MATLAB SimulinkDr. Ricardo Ramirez-Mendoza PhD and Ing. Aline Drivet MSME both work in the Mechatronics Engineering Program at the Center for Innovation in Design and Technology on the ITESM Campus in Monterrey, Mexico. They and their colleagues have performed some very innovative vehicle work with Adams from MSC.Software.ITESM Mini Baja vehicleTheir ultimate goal is to perform high-fidelity controlled dynamic (mechatronics) simulations on full vehicles by integrating Adams/Car with MATLAB Simulink. To achieve their goal, they are pursuing a methodical, step-by-step approach. In their first approach, they designed a control theory in Simulink and then implemented it in Adams/View using the embedded Controls Toolkit. In this way, they were able to co-simulate and analyze the behavior of an active suspension system on the physical Mini Baja vehicle that ITESM has used in SAE competitions. The objective of the active suspension is to improve vehicle maneuverability and ride quality.Model of the Mini Baja suspension in Adams/Car Model of the complete Mini Baja vehicle in Adams/CarThe Adams analysis simulated the vehicle driving on an uneven road at a constant speed of 40 km/hr. The road was computer-generated to be irregular and to match measured stochastic profiles that are typical. Two control strategies were implemented and compared a skyhook controller and a classical proportional + integral + derivative (PID) controller.Conceptual model of an active suspension with a Skyhook control strategyThe PID controller proved to be a better strategy than the skyhook controller in the overall vehicle performance. An average improvement (reduction) of 30% was obtained in the vertical acceleration at several key points on the vehicle which significantly improved the comfort and maneuverability of the vehicle. This coupled controlled-dynamics work, based on high-fidelity vehicle suspension model and controller models, enables research that progresses beyond traditional research based on simplified, approximate models.They presented their technical paper A Mini-Baja Active Suspension Modeling using Adams/Car at the IASTED conference in May 2005. You can obtain a complete copy by visiting this site: /Abstract.aspx?paperId=19548The second approach was to use Simulink and Adams/View to develop an advanced control system based on the MacPherson suspension in the Renault Scenic. In this step, the simulation was performed in Simulink using the suspension system from Adams/View as the mechanical plant being controlled.This work on Virtual Prototyping of an Active Suspension using Adams/View and MATLAB was presented at the MSC 2006 VPD Conference in Huntington Beach, California, and is scheduled for publication at the IFAC conference in Heidelberg, Germany, in November 2006. Advanced Simulink control system using the Adams MacPherson suspension subsystem (click images to enlarge) Active suspension control system schematic using subroutine from Adams as the mechanical plant Details of controller inputs and outputs shared with Adams Some preliminary results show improved performance with close loop MR damper suspension.Chassis vertical displacement with and without Skyhook controller Chassis vertical displacement with and without PID controllerTheir next step will be to use Adams/Car to model the dynamics of the full Scenic vehicle, including the chassis, suspension, steering, tires, and braking subsystems for advance control purposes.Renault Scenic vehicle Physical suspension in the Renault Scenic Virtual model of Renault Scenic suspension in AdamsThe authors have followed a methodical approach using data from their real Mini Baja and Renault vehicles to obtain model data as simulation inputs and to verify system performance as simulation output. This rigorous, step-by-step approach provides them with a solid foundation for their