Movie S2. Navigation of microrobots in blood vessels with different vessel diameter D and RBC volume fraction \(f\).  Specifically, from left to right, \(D\) = 12um, \(f\) ~ 10%; \(D\) = 25um, \(f\)~10%;  \(D\) = 50um, \(f\)~5%; \(D\) = 50um, \(f\)~10%.