[1] Univ Georgia, Coll Engn, 597 DW Brooks Dr, Athens, GA 30602 USA
[2] NYU, Tandon Sch Engn, 6 MetroTech Ctr, Brooklyn, NY 11201 USA
[3] Loughborough Univ, Sch Mech Elect & Mfg Engn, Loughborough LE11 3TU, England
[4] Queen Mary Univ London, Sch Engn & Mat Sci, Ashby Rd, London E1 4NS, England