Integration and Analysis of EPAS and Chassis System in FMI-based co-simulation
Paper in proceeding, 2019

The vehicle steering characteristics and active functions can be virtually developed with a high-fidelity electric power assisted steering (EPAS) model and a multibody chassis model. The simulation of the EPAS model requires small integration step due to high stiffness and interfacing with the controller. The multibody chassis model is computationally heavy for each integration step due to calculation of large matrices. A mono-simulation based on a single solver is not efficient for this case. Instead a co-simulation (solver coupling) approach has been used to overcome the drawbacks.In this paper the EPAS system and chassis system are modeled in Dymola and further exported as separate functional mockup units (FMUs) and integrated with the control algorithms in Matlab. A co-simulation based on the explicit parallel calculation scheme (Jacobi scheme) has been used. A huge simulation speed-up has shown the potential and effectiveness of the approach. To understand its accuracy and tolerance, analysis on the numerical error and dynamics of the coupled-system are given.


Chassis system

EPAS system



Weitao Chen

Chalmers, Mechanics and Maritime Sciences (M2), Vehicle Engineering and Autonomous Systems

Volvo Cars

Shenhai Ran

Volvo Cars

Bengt J H Jacobson

Chalmers, Mechanics and Maritime Sciences (M2), Vehicle Engineering and Autonomous Systems

Proceedings of the 13th International Modelica Conference

157 717-724 074
978-91-7685-122-7 (ISBN)

13th International Modelica Conference
Regensburg, Germany,

Virtual Architecture for Development and Verification of Chassis Mechatronic Systems

Volvo Cars, 2016-07-01 -- 2022-06-30.

European Commission (EC) (EC/H2020/675999), 2016-07-01 -- 2022-06-30.

Areas of Advance


Subject Categories

Vehicle Engineering

Control Engineering

Other Electrical Engineering, Electronic Engineering, Information Engineering



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