Multi-physics optimisation of an energy harvester device for automotive application Elvio Bonisoli, Francesco Di Monaco and Stefano Tornincasa Dipartimento di Ingegneria Gestionale e della Produzione, Politecnico di Torino, Torino, Italy, and Fabio Freschi, Luca Giaccone and Maurizio Repetto Dipartimento Energia, Politecnico di Torino, Corso Duca degli Abruzzi, Torino, Italy Abstract Purpose – Supplying remote wireless sensors is not an easy task if the site where the device is located is not easily accessible. In order to obtain direct measurements of the road-vehicle interactions, sensors must be placed inside the tyre environment thus a power supply must be available for their working there without any wire connection with the car main power. The paper aims to discuss these issues. Design/methodology/approach – An electro-mechanical energy harvester has thus been developed for supplying an automotive wireless sensor of pressure, temperature and acceleration to be placed on the inner line of a tyre. The primary energy source is the vibrations or variable accelerations imposed to the device and induced in the tyre by the wheeling. Findings – The harvester has been designed by means of a multi-physics optimisation based on an integrated electromagnetic-mechanical circuit simulator. Thus an automated optimisation of the device with respect to volume constraints, magnets dimensions, induction coils placement and size have been performed to increase the average power extracted from the device at different wheeling speeds. Originality/value – The use of the multi-physics environment together with automated optimisation technique has been tested for the first time on the electromagnetic harvester structure. Keywords Energy harvesting, Multiphysics, Optimal design, Applied electromagnetism Paper type Research paper Introduction The more and more widespread use of remote wireless sensors located in inaccessible sites makes their supply an interesting field of research. It is in fact critical to reach this goal when the use of electrochemical batteries and accumulators is not lasting enough to ensure a reasonable working time of the node. In literature several energy harvesting solutions are described (Priya and Inman, 2009; Mann and Sims, 2009; Saha et al., 2008). In the frame of a research project the Authors have worked in the design and realisation of an electromechanical energy harvesting device to be placed on the inner line of a tyre which is aimed at the supply of some sensors there placed. These sensors should broadcast, via high frequency coupling, to the car electronic system the state of The current issue and full text archive of this journal is available at www.emeraldinsight.com/0332-1649.htm COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering Vol. 33 No. 3, 2014 pp. 846-855 r Emerald Group Publishing Limited 0332-1649 DOI 10.1108/COMPEL-10-2012-0208 This work was performed under a research project with Pirelli Tyre S.p.A. The authors would like to thank Dr Giorgio Audisio, Dr Federico Mancosu, and Dr Massimo Brusarosco from Pirelli Tyre S.p.A. for their enthusiasm and driving force in the project. 846 COMPEL 33,3