Fault Tolerant Control with Additive Compensation for Faults in an Automotive Damper

International audienceAbstract--A novel Fault-Tolerant Controller is proposed for an automotive suspension system based on a Quarter of Vehicle (QoV) model. The design is divided in a robust Linear Parameter-Varying controller used to isolate vibrations from external disturbances and in a compensation mechanism used to accommodate actuator faults. The compensation mechanism is based on a robust fault detection and estimation scheme that reconstructs a fault on the semi-active damper; this information is used to reduce the failure effect into the vertical dynamics to achieve good control performances. Validations have been made over a QoV model in CarSimTM. Results show the effectiveness of the faulttolerant semi-active damper versus an uncontrolled damper; the improvement is 50.4% in comfort and 42.4% in road holding, by avoiding biases in the damper deflection

Characterisation of the Dynamics of an Automotive Suspension System for On-line Condition Monitoring

As the most critical system that determines the driving performance, passenger comfort and road safety of a vehicle, the suspension system has not been found to have adequate monitoring systems available to provide early warnings of possible faults online. To fill this gap, this study has focused on the investigation of the dynamic behaviour of the suspensions upon which a new on-line condition suspension monitoring approach was proposed and verified under different conditions. Specifically, the approach quantifies the modal shapes which are obtained based on an improved modal identification applying to acceleration responses at the four corners of the vehicle. To achieve this, the research was carried out by the means of dynamic modelling, numerical simulations, optimal measurement optimisations and subspace identification improvements based on a representative vehicle system, cost-effective measurement techniques and road standards. Firstly, a mathematical model with a seven degree-of-freedom (7-DOF) was developed in account of variable stiffness and damping coefficients, being applicable for computer simulation of the dynamic interaction between a vehicle and a road profile. To validate the proposed model during real operation, this study investigates a set of on-road experiments, to measure the acceleration of the vehicle body. Comparisons between the experimental and simulation paths demonstrated that, simulation results and measured on road results were found to be almost have similar trend. In the simulations the modal parameters (obtained theoretically) of a vehicle are: natural frequency, damping ratio and modal shapes and their characteristics are characterised under the influence of different suspension faults and operating conditions (loads and speed). It has found that the modal shapes are more independent of operating conditions and thereby reliable as indicators of faulty suspensions, compared with modal frequency and damping which are influenced more by operating conditions. Furthermore, the modal shape difference between left and right side responses are developed as the fault severity indicator. To obtain the modal shapes online reliably, an improved stochastic subspace identification (SSI) is developed based on an average correlation SSI. Particularly the implementation of optimal reference channels is achieved by comparing the average correlation signals which can be more efficient due to much smaller data sizes, compared with that raw data based spectrum analysis method used in original development. On road verification based on a commercial vehicle operating in normal road conditions shows that common suspension faults including inadequate damping faults and under-inflation of the tyre, induced one of the four shock absorbers, can be detected and diagnosed with acceptable accuracy. Therefore, it can be deduced that the SSI modal shape based detection techniques are effective and therefore promising to be used to diagnose and monitor the suspension system online

Fault Tolerant Control in a Semi-Active Automotive Suspension

[ES] Un nuevo controlador tolerante a fallas (FTC por sus siglas en inglés, Fault Tolerant Controller) activo es propuesto para una suspensión automotriz semi-activa, considerando un modelo de un cuarto de vehículo. El diseño está compuesto por: (1) un controlador no-lineal robusto utilizado para aislar las vibraciones en el vehículo causadas por perturbaciones externas y (2) un mecanismo de compensación usado para acomodar fallas aditivas en la fuerza de amortiguamiento. El mecanismo de compensación utiliza un módulo de detección y estimación de fallas robusto, basado en ecuaciones de paridad, para reconstruir la falla; esta información permite calcular la señal de compensación por medio de un modelo inverso del amortiguador para reducir el efecto de la falla en la dinámica vertical de la suspensión. Mientras que el controlador no-lineal, basado en la técnica de control de parámetros variantes lineales (LPV por sus siglas en inglés, Linear Parameter-Varying) está diseñado para aumentar el confort del pasajero y mantener el contacto llanta-suelo. Ante una falla en la fuerza de amortiguamiento, el FTC activo debe asegurar los desempeños de confort y seguridad utilizando la interacción entre el controlador LPV y el compensador. Resultados de simulación en CarSimTM muestran la efectividad del FTC activo respecto a un FTC pasivo y un amortiguador no controlado; el FTC pasivo depende del diseño para su capacidad tolerante, mientras que el FTC activo propuesto mejoró un 50.4% en confort y un 42.4% en agarre de superficie cuando ocurre una falla, en contraste con el amortiguador no-controlado que pierde totalmente su efectividad.[EN] A new active Fault Tolerant Controller (FTC) is proposed for an automotive semi-active suspension, by considering a quarter of vehicle model. The design is composed by: (1) a robust non-linear controller used to isolate vibrations into the vehicle caused by external disturbances and (2) a mechanism of compensation used to accommodate additive faults in the damping force. The compensation mechanism uses a robust fault detector, based on parity space, to estimate the fault; this information allows the computation of the compensation signal by using the inverse dynamics of a damper model to reduce the fault effect into the vertical dynamics of the suspension. The non-linear controller, based on the Linear Parameter-Varying (LPV) control theory, is designed to increase the passengers comfort and ensure the wheel-road contact. When a fault occurs in the damping force, the active FTC must hold the performances of comfort and road holding by using the interaction between the LPV controller and the compensatory module. Simulation results in CarSimTM show the effectiveness of the proposed active FTC versus a passive FTC and an uncontrolled damper; the passive FTC needs to include all faults into its design for having a good fault-tolerant capability, while the proposed active FTCimproves a 50.4% in comfort and 42.4% in road holding when a fault occurs, in contrast with the uncontrolled damper that loses completely its effectiveness. Este trabajo fue parcialmente apoyado por el proyecto bilateral México-Francia CONACyT PCP 03/10 y el proyecto Francés INOVE ANR 2010 BLAN 0308.Tudón Martínez, JC.; Varrier, S.; Morales Menéndez, R.; Sename, O. (2016). Control Tolerante a Fallas en una Suspensión Automotriz Semi-Activa. Revista Iberoamericana de Automática e Informática industrial. 13(1):56-66. https://doi.org/10.1016/j.riai.2015.02.009OJS5666131Apkarian, P., & Gahinet, P. (1995). A convex characterization of gain-scheduled H/sub ∞/ controllers. IEEE Transactions on Automatic Control, 40(5), 853-864. doi:10.1109/9.384219Börner, M., Isermann, R., Schmitt, M., 2002. A sensor and process fault detection system for vehicle suspension systems. In: SAE 2002 World Congress & Exhibition. USA, technical paper: 2002-01-0135.Chamseddine, A., & Noura, H. (2008). Control and Sensor Fault Tolerance of Vehicle Active Suspension. IEEE Transactions on Control Systems Technology, 16(3), 416-433. doi:10.1109/tcst.2007.908191Chow, E., & Willsky, A. (1984). Analytical redundancy and the design of robust failure detection systems. IEEE Transactions on Automatic Control, 29(7), 603-614. doi:10.1109/tac.1984.1103593Do, A., Sename, O., Dugard, L., 2012. Ch.5 LPV modelling and control of semi-active dampers in automotive systems. Control of linear parameter varying systems with applications by Mohammadpour and Scherer, Springer.Fergani, S., Sename, O., Dugard, L., 2014. A LPV/Hinf fault tolerant control of vehicle roll dynamics under semi-active damper malfunction. In: Proc. of the American Control Conf. USA, pp. 4482-4487.Fischer, D., Börner, M., Schmitt, J., & Isermann, R. (2007). Fault detection for lateral and vertical vehicle dynamics. Control Engineering Practice, 15(3), 315-324. doi:10.1016/j.conengprac.2006.05.007Fischer, D., & Isermann, R. (2004). Mechatronic semi-active and active vehicle suspensions. Control Engineering Practice, 12(11), 1353-1367. doi:10.1016/j.conengprac.2003.08.003Gáspár, P., Szabó, Z., & Bokor, J. (2012). LPV design of fault-tolerant control for road vehicles. International Journal of Applied Mathematics and Computer Science, 22(1), 173-182. doi:10.2478/v10006-012-0013-xGuo, S., Yang, S., & Pan, C. (2006). Dynamic Modeling of Magnetorheological Damper Behaviors. Journal of Intelligent Material Systems and Structures, 17(1), 3-14. doi:10.1177/1045389x06055860Ezeta, J. H., Mandow, A., & Cerezo, A. G. (2013). Los Sistemas de Suspensión Activa y Semiactiva: Una Revisión. Revista Iberoamericana de Automática e Informática Industrial RIAI, 10(2), 121-132. doi:10.1016/j.riai.2013.03.002Kim, H., & Lee, H. (2011). Fault-Tolerant Control Algorithm for a Four-Corner Closed-Loop Air Suspension System. IEEE Transactions on Industrial Electronics, 58(10), 4866-4879. doi:10.1109/tie.2011.2123852Kim, J., & Lee, H. (2011). Sensor fault detection and isolation algorithm for a continuous damping control system. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 225(10), 1347-1364. doi:10.1177/0954407011404493de-J Lozoya-Santos, J., Morales-Menendez, R., Ramirez-Mendoza, R., Tudón-Martinez, J. C., Sename, O., & Dugard, L. (2012). Magnetorheological damper—an experimental study. Journal of Intelligent Material Systems and Structures, 23(11), 1213-1232. doi:10.1177/1045389x12445035Manzone, A., Pincetti, A., Costantini, D., 2001. Fault tolerant automotive systems: An overview. In: Proc. of the 7th Inter. On-Line Testing Workshop. Italy, pp. 117-121.Poussot-Vassal, C., Sename, O., Dugard, L., Gáspár, P., Szabó, Z., & Bokor, J. (2008). A new semi-active suspension control strategy through LPV technique. Control Engineering Practice, 16(12), 1519-1534. doi:10.1016/j.conengprac.2008.05.002Poussot-Vassal, C., Spelta, C., Sename, O., Savaresi, S. M., & Dugard, L. (2012). Survey and performance evaluation on some automotive semi-active suspension control methods: A comparative study on a single-corner model. Annual Reviews in Control, 36(1), 148-160. doi:10.1016/j.arcontrol.2012.03.011Qiu, J., Ren, M., Guo, Y., & Zhao, Y. (2011). Active fault-tolerant control for vehicle active suspension systems in finite-frequency domain. IET Control Theory & Applications, 5(13), 1544-1550. doi:10.1049/iet-cta.2010.0519Scherer, C., Gahinet, P., & Chilali, M. (1997). Multiobjective output-feedback control via LMI optimization. IEEE Transactions on Automatic Control, 42(7), 896-911. doi:10.1109/9.599969Tudón-Martínez, J., Varrier, S., Morales-Menendez, R., Ramírez-Mendoza, R., Koenig, D., Martínez, J.-J., Sename, O., 2013a. Fault tolerant control with additive compensation for faults in an automotive damper. In: Proc. of the 10th IEEE Int. Conf. on Networking, Sensing and Control. France, pp. 810–814.Tudón-Martínez, J., Varrier, S., Sename, O., Morales-Menendez, R., Martínez, J., Dugard, L., 2013b. Fault tolerant strategy for semi-active suspensions with LPV accommodation. In: Proc. of 2nd Int. Conf. on Control and Fault Tolerant Systems. France, pp. 631-636.Varrier, S., Koenig, D., Martínez, J.-J., 2012. Robust fault detection for vehicle lateral dynamics. In: Proc. of the 51st IEEE Conf. on Decision and Control. USA, pp. 4366-4371.Zhang, Y., & Jiang, J. (2008). Bibliographical review on reconfigurable fault-tolerant control systems. Annual Reviews in Control, 32(2), 229-252. doi:10.1016/j.arcontrol.2008.03.00