Passive dynamic walker’s walking is stabilized by using Constraining Sole Shape. In this research, we replace effect of Constraining Sole Shape with the Constraining Pin. We called Constraining Pin the Constraining Foot Mechanism. Passive dynamic walker attached Constraining Foot Mechanism can walk while 2 minutes. However apposite height of Constraining Pin on ramp has been unknown. Passive dynamic walker equipped with gyro sensor to derive apposite height of Constraining Pin. Then we measure angular velocity of passive dynamic walker from gyro sensor. On the receiving the results, we consider apposite height of Constraining Pin. Moreover, we consider apposite height of Constraining Pin from numerical simulation results.