the modified grounding timing is computed so as to satisfy {HEAD ~ the ZMP equation} under {TAIL ~ the first leg ZMP restraint condition} and the second leg ZMP restraint condition 
under
the modified grounding timing is computed so as to satisfy { HEAD ~ the ZMP equation } under { TAIL ~ the first leg ZMP restraint condition } and the second leg ZMP restraint condition
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH