Fluidic force and wake velocity of 3D body with four limbs in uniform flow

Robots that operate at a disaster site have been proposed and the dispatch of rescue robots to such is required. However, discussion on transport these insufficient. One method transporting use an airplane parachute. In order safely drop by parachute, it important investigate aerodynamics characteristics in free fall before opening present study, fluidic forces acted robot wake velocities behind were measured using load cell particle image velocimetry (PIV) uniform flow ranges 4 22 m/s. addition, bending angles 30°, 45° 60° evaluated terms aerodynamic coefficients, streamlines vorticity wake. As result, changes obtained due number limbs. A vortex pair appeared wake, recirculation region became smaller as limbs increases. coefficient for force z direction was maximum angle type-D model with two bent size position bending-limb side.