The advantage of rubble mound roughness measurement by walking robot

The advantage of the measurement of rubble mound roughness by leg motion of a walking robot is that it is not affected by long-period waves. Using a pressure gauge alone, it takes long time to measure the accurate depth. The combination of a pressure gauge and leg motion is one solution. At the starting and stopping points, measure the water pressure for a time enough to eliminate the affect of long-period waves. Between those two points, measure the roughness by leg motion of an aquatic walking robot. By a field test at a breakwater construction site 25 m deep, it is proved that this method has advantages in the sea where long-period waves of over 12 seconds.