Design and Analysis of the CES Semi-active Suspension System by Öhlins Racing. Matteo Pelosi 2015 Hydraulikdagarna March 16 th, Linköping, Sweden

Transcription

1 Design and Analysis of the CES Semi-active Suspension System by Öhlins Racing Matteo Pelosi 2015 Hydraulikdagarna March 16 th, Linköping, Sweden

2 Contents Öhlins Racing AB, Intro Öhlins Systems, CES Öhlins Systems Analysis, CAE CES-TTX Damping System CES Valve TTX-CES Shock Absorber Force Feedback Control Vehicle Dynamics Conclusions 2

3 Öhlins Racing AB ADVANCED SUSPENSION TECHNOLOGY 3

4 Öhlins Product Areas HYDRAULIC SUSPENSION SYSTEMS Damping through controlled oil flow metering Different levels of system complexity 4

5 Öhlins Racing Systems Conventional & Mechatronics Conventional Systems, damping adjusted by manual fixed steps, i.e. clicks through screws and knobs EC, damping adjusted electronically by stepper motors based on fixed settings. Smart EC, damping adjusted while riding based on state information, i.e. throttle, brake, velocity, acceleration... CES, damping is continuously adjusted based on state information, i.e. throttle, brake, velocity, acceleration 5

6 Öhlins Semi-active Suspension CES Proprietary technology developed since 1984 In use by several major automotive OEMs, >4 million sold Semi-Active Damping 6

7 Öhlins Systems Analysis CAE Support Vehicle Dynamics Controls 1D Multi-physics 3D CFD, FSI, FEM Cars, Motorcycles Mechatronics Dampers Valves Sub-Assemblies Success factor for truly accurate and useful results: Co-Simulation! 7

8 CES-TTX Damping System Overview Öhlins mechatronic system modeling example, including hydraulic valves, shock absorber, automatic controls and vehicle dynamics Hypersport Motorcycle Öhlins CES-TTX Shock Öhlins CES Valve Öhlins ECU Application and coupling of different simulation domains/strategies: 1D modeling, 3D CFD/FSI, controls theory, vehicle dynamics 8

9 CES Valve Modeling Overview Solenoid 1D Model Öhlins TTX CES Shock Pilot Stage 1D Model 2-stage pilot operated pressure control valve Capturing valve hydro-mechanical dynamics Main Stage 1D Model 1D model optimized to capture flow forces, flow coefficients, friction Model used to study novel valve designs & several physical behaviours 9

10 CES Valve Modeling Reduced Order Modeling Special submodels for valve stages to include information from 3D CFD/FSI analysis: weak/offline coupling Shim Orifice Submodel Pilot Stage CFD Enhanced 1D Model Metering ANSYS Fluent CFD ASCII tables for flow forces & flow coefficients as input to C++ submodels Pelosi, M., Subramanya, K. and Lantz, J Investigation on the Dynamic Behavior of a Solenoid Hydraulic Valve for Automotive Semi-Active Suspensions Coupling 3D and 1D Modeling. Proc. of the 13th Scandinavian International Conference on Fluid Power, Linköping, Sweden. 10

11 CES Valve Modeling Validation A p-q test cycle is simulated, where the pilot stage is fed by successive ramps of flow rate and excited at different levels of current CES Super-component 11

12 CES Valve Modeling Validation Low speeds & high speed regions compare well at all currents thanks to ROM i High Speeds i/i max Low Speeds 12

13 CES-TTX Damping System Shock Absorber Hypersport Motorcycle Öhlins CES-TTX Shock Öhlins CES Valve Öhlins ECU 13

14 CES-TTX Shock Modeling Overview Twin-tube shock absorber with double CES valves configuration Separate compression & rebound F damping Coupling of 1D super-components library Velocity Parameterization through physical knowledge, distributed simulations and manual tuning 14

15 CES-TTX Shock Modeling Static & Dynamic Validation Dynamometer CES-TTX shock model used to predict & understand shock absorber behaviors: - Static Testing: velocity ramp input - Dynamic Testing: velocity sine wave input vs LMS AMESim Sadeghi Reineh, M. and Pelosi, M., Physical Modeling and Simulation Analysis of an Advanced Automotive Racing Shock Absorber using the 1D Simulation Tool AMESim. SAE Int. J. Passeng. Cars - Mech. Syst. 6. doi: /

16 Modeling Libraries Encrypted Supercomponents, Black Box Export Development of proprietary library of custom submodels & super-components Internal and external sharing of advanced non-linear models Super-components CES valves Öhlins forks, shocks Other dampers Submodels Custom orifices Special spools Special poppets 16

17 CES-TTX Damping System Automatic Controls Hypersport Motorcycle Öhlins CES-TTX Shock Öhlins CES Valve Öhlins ECU 17

18 Force Feedback Control Main Objective Develop a shock controller that tries to follow a given force reference using feedback from a force sensor mounted inline with the damper rod CES solenoid valves Öhlins ECU Force Sensor Enhance understanding of input control current to force dynamics using model based approach Control structure in Matlab/Simulink Evaluate controller performance using the damping system model as virtual hardware through AMESim/Simulink co-simulation F damping 18

19 Force Feedback Control The Controller Simulink Co-Sim AMESim Damping system control strategies development & verification Environments cosimulations to study mechatronic system behaviour Ideal & real inputs to the co-simulation model 19

20 Force Feedback Control Numerical Results Step Response Clipped Sinusoidal Force Reference Sinusoidal Velocity Input Sinusoidal Force Reference Sinusoidal Velocity Input Input data from real track/road testing SiL, HiL Testing on real damper hardware 20

21 CES-TTX Damping System Vehicle Dynamics Hypersport Motorcycle Öhlins CES-TTX Shock Öhlins CES Valve Öhlins ECU 21

22 Vehicle & Systems Co-Simulation Intro Öhlins Mechatronic System coupled with vehicle dynamics simulation Study control strategy & mechatronics behavior on full vehicle Simulation of standard test cycles & full test tracks Simulink AMESim Co-Sim 22

23 Vehicle & Systems Co-Simulation Numerical Results Monitor several simulation parameters from front and rear suspension and full vehicle Karlskoga Motorstadion - Gelleråsen Damping Forces Vertical Acceleration Verify different control software and hydromechanical hardware settings before physical test Investigate influence of hardware and software design changes over vehicle performance Correlate comments from expert riders with Öhlins mechatronics behavior 23

24 Conclusions The use of CAE tools within Öhlins Racing R&D has been shown: coupling of modeling environments through 1D system co-simulations & 3D multiphysics simulations 3D simulations paramount for physical understanding at a detailed, distributed components level (CFD, FSI, FEM) 1D modeling to deepen the knowledge of conventional and mechatronic systems second order dynamics behavior Co-simulations with Matlab Simulink allows implementation, study and comparison of different control strategies Vehicle dynamics modeling allows further understanding over interactions of Öhlins products with driver/rider and OEM vehicles 24

25 Thank You! Questions?