Attention to the environment is significantly increasing over the last years. The automotive world is identified as one of the biggest sources of polluting gases due to classic internal combustion engine emissions. This has led to the implementation of electric vehicles. Due to the different layouts and the promptness of the electric motors, the vehicle control logic should be rediscussed. This thesis aims to design a multi-actuated control logic for the lateral dynamics control of an electric formula vehicle which will compete in the EFSAE championship, an engineering design competition among several universities in the world. The are two available actuators: the torque vectoring (TV), at disposal thanks to two motors, one for each wheel, on the rear axis and the rear wheels steering (RWS). The latter has been engineered in this thesis to be implemented on the real vehicle and to better model its dynamic to have a more precise control model. Firstly, this dissertation carries out a review of the state of the art of active control on road vehicles, exploring their evolution during the years landing to the ones implemented on FEVs. A briefly review on the steering components and the several implementation possibilities is also available. The dissertation continues with the RWS design, focusing on the gearmotor choice and on the FEM study of the main structural parts. Eventually, a study of the vehicle control system is presented, aiming to control simultaneously the two variables which, according to the literature, influence the most the car behaviour, i.e. the side slip angle and the yaw rate. Thanks to the right references, the implemented control target is to obtain a high-performance vehicle capable to recover the stability in critical conditions. The control chapter also describes how the multi-actuation is implemented. A phase portrait study has been carried out in order to obtain efficiency maps, through which the use of an actuator over the other is maximized according to the vehicle state. Then the control logic is described. The controller is a fuzzy sliding mode control, which combines a super-twisting SMC with a FLC, the first one generates the control action, while the second one adapts the sliding surface to the vehicle state. The final control action is weighted through the performance indexes. Finally, different numerical simulations, run in Matlab-Simulink environment, are reported and results are discussed to show the controller performances.
L’attenzione verso l’ambiente è cresciuta sempre di più negli ultimi anni. Il mondo dell’automotive è riconosciuto come una delle maggiori fonti di gas inquinanti a causa delle emissioni dei classici motori a combustione interna. Motivo che ha portato allo sviluppo di veicoli elettrici. Per il differente layout di questi e la prontezza dei motori elettrici, la logica di controllo del veicolo deve essere rivista. Questa tesi aspira a progettare un controllo multi-attuato per la dinamica laterale di un veicolo formula elettrico che parteciperà nel campionato EFSAE, una competizione tra diverse università nel mondo. Gli attuatori disponibili sono due: il torque vectoring (TV), a disposizione grazie a due singoli motori, uno per ruota, e il sistema di sterzo posteriore (RWS). Quest’ultimo è stato progettato in questa tesi per essere implementato sul veicolo e per avere un modello affidabile della sua dinamica da usare nel modello di controllo. Inizialmente la dissertazione presenta lo stato dell’arte dei controlli sui veicoli, esplorando la loro evoluzione sino a quelli attualmente usati sui veicoli elettrici. E anche presentata una breve revisione sui componenti dello sterzo e le differenti configurazioni. In seguito, la tesi continua con la progettazione del RWS, concentrandosi sulla scelta del moto-riduttore e sullo studio FEM delle parti strutturali più importanti. L’attenzione si sposta poi sullo studio del sistema di controllo del veicolo, che ha lo scopo di gestire le due variabili che, secondo la letteratura, più influenzano il comportamento dinamico del veicolo, ossia la velocità di imbardata e l’angolo di assetto. Grazie ai giusti riferimenti, il controllo è costruito per ottenere un veicolo performante e che riesca a recuperare la stabilità in condizioni critiche. Il capitolo sul controllo tratta anche dell’implementazione della multi-attuazione. Uno studio nel piano di fase è stato fatto per produrre delle mappe di efficienza, attraverso le quali è definito l’uso di un attuatore rispetto a un altro in base allo stato del veicolo. Successivamente, la logica di controllo è descritta. Essa si basa su un controllo ‘fuzzy sliding mode’, che combina un super-twisting SMC con una FLC; il primo genera l’azione di controllo, mentre il secondo adatta la superficie di sliding allo stato del veicolo. L’azione finale del controllo è pesata tramite gli indici di performance. Infine diverse simulazioni numeriche, in Matlab-Simulink, sono state eseguite e commentate per mostrare le capacità del controllo.
Fuzzy sliding mode control for vehicle lateral dynamics combining torque vectoring with four wheels steering for electric FSAE vehicle
Giambone, Andrea;Lussana, Fabio
2019/2020
Abstract
Attention to the environment is significantly increasing over the last years. The automotive world is identified as one of the biggest sources of polluting gases due to classic internal combustion engine emissions. This has led to the implementation of electric vehicles. Due to the different layouts and the promptness of the electric motors, the vehicle control logic should be rediscussed. This thesis aims to design a multi-actuated control logic for the lateral dynamics control of an electric formula vehicle which will compete in the EFSAE championship, an engineering design competition among several universities in the world. The are two available actuators: the torque vectoring (TV), at disposal thanks to two motors, one for each wheel, on the rear axis and the rear wheels steering (RWS). The latter has been engineered in this thesis to be implemented on the real vehicle and to better model its dynamic to have a more precise control model. Firstly, this dissertation carries out a review of the state of the art of active control on road vehicles, exploring their evolution during the years landing to the ones implemented on FEVs. A briefly review on the steering components and the several implementation possibilities is also available. The dissertation continues with the RWS design, focusing on the gearmotor choice and on the FEM study of the main structural parts. Eventually, a study of the vehicle control system is presented, aiming to control simultaneously the two variables which, according to the literature, influence the most the car behaviour, i.e. the side slip angle and the yaw rate. Thanks to the right references, the implemented control target is to obtain a high-performance vehicle capable to recover the stability in critical conditions. The control chapter also describes how the multi-actuation is implemented. A phase portrait study has been carried out in order to obtain efficiency maps, through which the use of an actuator over the other is maximized according to the vehicle state. Then the control logic is described. The controller is a fuzzy sliding mode control, which combines a super-twisting SMC with a FLC, the first one generates the control action, while the second one adapts the sliding surface to the vehicle state. The final control action is weighted through the performance indexes. Finally, different numerical simulations, run in Matlab-Simulink environment, are reported and results are discussed to show the controller performances.File | Dimensione | Formato | |
---|---|---|---|
TESI_GL.pdf
accessibile in internet per tutti
Descrizione: Tesi Giambone Lussana
Dimensione
10.82 MB
Formato
Adobe PDF
|
10.82 MB | Adobe PDF | Visualizza/Apri |
I documenti in POLITesi sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
https://hdl.handle.net/10589/175010