Flow Analysis around Multi-Legged Underwater Robot "Crabster" to Evaluate Current Loads

다관절 해저로봇 'Crabster'에 작용하는 조류하중 산정 및 유동해석

Park, Yeon-Seok;Kim, Wu-Joan;Jun, Bong-Huan

  • Received : 2012.07.23
  • Accepted : 2012.10.25
  • Published : 2012.10.31


In this study, numerical simulations were performed to evaluate the current loads acting on the multi-legged underwater robot "Crabster" with a variety of incident angles using the ANSYS-CFX package. The Reynolds-averaged Navier-Stokes equations were solved to simulate the fluid flow around Crabster to calculate the forces and moments induced by incoming currents with various angles. First, to assess the posture stability of the body, the forces and moments were calculated with various incident angles when the current acted in the vertical and horizontal directions. Next, two forms of legs (box and foil types) were evaluated to determine the hydrodynamic force variation. Finally, the current forces and moments acting on the Crabster body with the legs attached were estimated.


Underwater robot;Crabster;Numerical simulation;Current;Hydrodynamic force;Reynolds Averaged Navier-Stokes equation


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Supported by : 국토해양부