ETD system

Electronic theses and dissertations repository


Tesi etd-03262014-180407

Thesis type
Tesi di dottorato di ricerca
Smart materials and vehicle efficiency. Design and experimentation of new devices.
Settore scientifico disciplinare
Corso di studi
relatore Prof. Forte, Paola
tutor Prof. Frendo, Francesco
Parole chiave
  • MR
  • Magnetorheological fluids
  • Experimentation
  • Design
  • Shape memory alloys
  • SMA
  • Vehicle effciciency
Data inizio appello
Riassunto analitico
In this dissertation the activities carried out during the PhD are comprehensively<br>described. The research mainly focused on the development<br>of novel smart devices aimed at disengaging auxiliaries in internal combustion<br>engine vehicles. In particular, the activities dealt with modeling,<br>design, manufacturing and testing different fail-safe magnetorheological<br>clutch prototypes, in the framework of a project funded by Regione<br>Toscana, which involved two departments of the University of Pisa and<br>Pierburg Pump Technology - Stabilimento di Livorno.<br>After an extended literature review, several concepts of the clutch<br>were proposed, which led to the design of the first magnetorheological<br>prototype. An intensive experimental campaign was conducted, which<br>involved several prototypes. A particular attention was focused on the<br>measurement and analysis of the torque transmitted by the clutch in<br>different operating conditions and new indices were proposed to objectively<br>analyze the performances of magnetorheological clutches in general. On<br>the basis of the results of the first experimental phase, the limits of the<br>first design were analyzed and a novel prototype was developed, which<br>succeeded in fulfilling all the design specifications.<br>Further analyses were carried out in order to develop a clutch model<br>starting from the experimental results. The effect of clutch heating was<br>considered and a complete model of the clutch based on neural networks<br>was proposed. The model was capable of taking into account the effect<br>of the main parameters influencing the torque characteristic and may be<br>used in a vehicle simulator or in a hardware-in-the-loop bench.<br>Finally, an additional component to be connected to the clutch, which<br>made use of shape memory alloys, was developed and tested during the<br>visiting period at the University of Toledo (OH), USA.