Politecnico di Torino (logo)

Simulink control model of an active pneumatic suspension system for passenger cars

Davide Franz

Simulink control model of an active pneumatic suspension system for passenger cars.

Rel. Giovanni Maizza. Politecnico di Torino, Corso di laurea magistrale in Mechatronic Engineering (Ingegneria Meccatronica), 2019

PDF (Tesi_di_laurea) - Tesi
Licenza: Creative Commons Attribution Non-commercial No Derivatives.

Download (5MB) | Preview

Starting from 1950, greater interest has been gained on active suspensions with respect to semi-active and passive systems. In a vehicle, the suspension system aims at satisfying the contrasting requirements of both comfort and handling, by insulating passengers from vehicle vibrations and providing constant tyre-road contact, respectively. One of the main advantages of active suspension is to provide the possibility of managing the trade off between vertical acceleration reduction and suspension travel usage through the choice of a suitable control strategy. The aim of this work is to set up a basic control model of an automotive active pneumatic system, to meet the essential performances of control and comfort. The active pneumatic suspension system is based on a set of equations for the quarter car model, the pneumatic valve and the air spring. The quarter car model is derived from the Second Newton's Law and accounts for the dynamics of a quarter of the vehicle mass (sprung mass) and of the suspension and tyre mass (unsprung mass). The proportional valve is modeled using the orifi ce equation for the air mass flow rate, exploiting a proportional relationship between the valve active area and the control input u. It is responsible for the air flow regulation to the actuator. The air spring, i.e. the actuator, is represented through the pressure variation equation inside a variable volume chamber. This variation is responsible for the active force production. To generate the right control signal u and to deal with the system nonlinearities, mainly arising from the complex air behavior, a nonlinear control algorithm based on backstepping technique is adopted. As last step, simulations of the developed model are run in MATLAB-Simulink environment under different driving scenarios to test the effectiveness of the adopted solution with respect to a passive system.

Relators: Giovanni Maizza
Academic year: 2019/20
Publication type: Electronic
Number of Pages: 65
Corso di laurea: Corso di laurea magistrale in Mechatronic Engineering (Ingegneria Meccatronica)
Classe di laurea: New organization > Master science > LM-25 - AUTOMATION ENGINEERING
Aziende collaboratrici: FRAP SRL
URI: http://webthesis.biblio.polito.it/id/eprint/13113
Modify record (reserved for operators) Modify record (reserved for operators)