Algorithm 1: Power assistance with user’s posture (v = ZO)

Input variables: $S_g$, $f_f$, $f_d$, v While $S_g$ = PS or PL  If $f_f$ = (L ⋁ M) ⋀ $f_d$ = S, then controller output = slower or reversal  else controller output = forward While $S_g$ = ZO  If ($f_f$ = (L ⋁ M) ⋀ $f_d$ = S) ⋁ ($f_f$ = L ⋀ $f_d$ = M), then   controller output = slow reversal else if ($f_f$ = (L ⋁ M) ⋀ $f_d$ = L) ⋁ ($f_f$ = M ⋀ $f_d$ = M), then controller output = forward slowly else stay the same While $S_g$ = NS or NL  If ($f_f$ = M) ⋀ ($f_d$ = L ⋁ M), then controller output = slower than general  else controller output = reverse (fast or slow) End