An impact absorbing mechanism, provided to a foot 5 of an extremity of
each of two movable legs 2 of a bipedal walking robot 1 having the two
movable legs 2, includes: an upper base plate 5-a joined to a foot joint
4 of each of the movable legs 2; a lower base plate 5b positioned below
the upper base plate, and being opposite to the upper base plate; and
three elastic members 6 anisotropic in terms of elasticity, which are
arranged at equal intervals in the circumferential direction about the
yaw axis YA extending in a direction perpendicular to the upper base
plate 5a, between the upper base plate 5a and the lower base plate 5b,
each of which allows the lower base plate 5b to make elastic displacement
relative to the upper base plate 5a in the same direction as axis YA
extends, while each of which inhibits the lower base plate 5b from making
elastic displacement relative to the upper base plate 5a in directions
orthogonal to the yaw axis direction, and which join the upper base plate
5a and the lower base plate 5b elastically. This can simplify a
calculation by a CPU concerning control of the walking of the walking
robot. This can prevent disturbance, which would otherwise occur due to
the friction resistance stemming from the physical interference by the
rigid members. In addition, this can prevent the 6-axis force sensor from
being broken, and can also prevent an equivalent to the breakage.