[1] Univ Michigan, Dept Biomed Engn, Ann Arbor, MI 48109 USA
[2] Univ Roma Tor Vergata, Dept Elect Engn, Rome, Italy
[3] Politecn Milan, Dipartimento Elettron Informaz & Bioingn, I-20133 Milan, Italy
[4] Univ Quebec, INRS EMT, Ste Foy, PQ G1V 2M3, Canada
[5] Tsinghua Univ, Sch Med, Dept Biomed Engn, Beijing 100084, Peoples R China
[6] Univ Ghent, Dept Elect & Informat Syst, B-9000 Ghent, Belgium
[7] Brown Univ, Ctr Neurorestorat & Neurotechnol, Rehabil R&D Serv, VA Med Ctr, Providence, RI 02912 USA
[8] Brown Univ, Sch Engn, Providence, RI 02912 USA
[9] Univ N Dakota, Dept Elect Engn, Grand Forks, ND 58201 USA
[10] Univ Roma Tor Vergata, Dept Civil Engn, Rome, Italy
[11] Univ Roma Tor Vergata, Dept Comp Sci & Engn, Rome, Italy
[12] Univ Michigan, Dept Phys Med & Rehabil, Ann Arbor, MI 48109 USA