Article History
Received: 27 November 2017
Accepted: 25 April 2018
First Online: 15 May 2018
Change Date: 13 July 2018
Change Type: Correction
Change Details: The original version of this Article omitted the following from the Acknowledgements: Z. Leghtas' primary affiliation is Centre Automatique et Systèmes, Mines ParisTech. This has been corrected in both the PDF and HTML versions of the Article.
Competing interests
: The authors declare no competing interests.