Masako Nozawa Yoshiyuki Sankai Control Method of Walking Speed and Step Length for Hybrid Assistive Leg. 220-227 2002 conf/icchp/2002 ICCHP http://link.springer.de/link/service/series/0558/bibs/2398/23980220.htm db/conf/icchp/icchp2002.html#NozawaS02