Co-simulation of Semi-active Dampers for Durability Road Load Simulations

Abstract

Active chassis systems are becoming the norm today, especially in the premium car segments. These systems provide the ability to adapt to varying road conditions. It is critical to have CAE methods that model active systems since they significantly influence the accuracy of computed durability road loads used in vehicle design. There is a certain amount of complexity associated with creating simulation models of active vehicle systems. To enhance prediction accuracy, full-fidelity models of the controls guiding the active systems have to be included. These control models are often delivered as black boxes from the supplier. The first part of the presentation outlines the CAE strategy for active systems at Volvo Cars Durability Centre, with a particular focus on co-simulation of semi-active dampers. The co-simulation strategy forms the basis for simulation-led predictions of strength, endurance, durability, and road loads characteristics of vehicles with active chassis systems. The co-simulation approach is compared and contrasted against a simpler approach involving passive simulations. The incremental improvement in the accuracy of the computed road loads using the co-simulation approach is detailed under various road conditions and vehicle events. These include single-sided vertical impact, driving through a pothole, drop-off rebound, and the Belgian Pave. The second part of the presentation describes the implementation of a customized simulation process at Volvo Cars Durability Centre that enables efficient co-simulation, at scale, with minimal computational overhead. Processes and methods have been developed previously at Volvo Cars Durability Centre to automatically submit a whole suite of fatigue simulation events. Still, for co-simulation methods, the only option had been primarily manual. A customized process enhancement is presented in the new implementation, which seamlessly integrates cross-platform co-simulation into Volvo Cars' current automated simulation processes with minimal additional computational overhead. This process implementation will serve as a framework for similar co-simulation implementations in the future at Volvo.