Abstract: A bending and stretching motion assist device includes: left and right thigh links; left and right lower leg links swingably coupled to lower ends of the thigh links; a torso mount member having an annular shape and supporting upper ends of the left and right thigh links swingably on respective sides of left and right hip joints; left and right lower leg mount members respectively attached to lower ends of the left and right lower leg links; an assist force generation device configured to generate assist force in a stretching direction between the lower leg links and the thigh links to assist bending and stretching motion of lower limbs; and a buttocks support member extending between parts of the torso mount member adjacent to connecting parts that connect the torso mount member to the left and right thigh links, respectively, and including a buttocks pad.

Abstract: In a legged mobile robot (10) having a motor (42) that rotates the ankle joint (26R (26L)) about a right-and-left axis of the robot (26RY (26LY)) and a speed reducer (58) that reduces speed of an output of the motor, wherein the motor is disposed at a same position as the knee joint (22R (22L)) or at the thigh link (16R (16L)) such that the speed reducer is disposed at the shank link. With this, it becomes possible to reduce the weight of the distal end of the leg (12R (12L)) can be reduced, whereby enabling to reduce the inertial force generated in the leg during movement or locomotion of the robot.

Abstract: In a legged mobile robot (10) having a motor (42) that rotates the ankle joint (26R (26L)) about a right-and-left axis of the robot (26RY (26LY)) and a speed reducer (58) that reduces speed of an output of the motor, wherein the motor is disposed at a same position as the knee joint (22R (22L)) or at the thigh link (16R (16L)) such that the speed reducer is disposed at the shank link. With this, it becomes possible to reduce the weight of the distal end of the leg (12R (12L)) can be reduced, whereby enabling to reduce the inertial force generated in the leg during movement or locomotion of the robot.