Abstract: In a legged mobile robot (1), each leg (2) has at least a first joint (16) and a second joint (18, 20) located below the first joint in the gravitational direction, and the actuator that drives the second joint (54, 56) is located at least one of a position same as that of the first joint and a position (28) above the first joint in the gravitational direction. With this, it becomes possible to lighten the weight of the ground-contacting ends of the legs and thereby provide a legged mobile robot enabling reduction of the inertial forces occurring in the legs during moving, particularly during high-speed moving.

Abstract: A landing shock absorbing device 18 disposed in a foot mechanism 6 of a leg of a robot, wherein an inflatable bag-like member 19 (variable capacity element) is provided at a bottom face side of the foot mechanism 6. The bag-like member 19 is constructed of an elastic material such as rubber. The air in atmosphere may flow into and out of the bag-like member 19 by inflow/outflow means 20 equipped with a solenoid valve 27, and the like. In a lifting state of the foot mechanism 6, inflow of the air into the bag-like member 19 is controlled, thereby controlling the final height of the bag-like member 19 in an inflated state to the height in response to a gait type of the robot. While properly reducing an impact load during a landing motion of the leg of a legged mobile robot depending on the gait type of the robot, stability of a posture of the robot may easily be secured, resulting in allowing a configuration to be lighter in weight.

Abstract: In a state wherein a solenoid switching valve in a gas passage in communication with air chambers is closed, an assist device produces an assisting driving force by compression or expansion of a gas as a knee joint (specific joint) of a leg bends or stretches, and applies the produced assisting driving force to the knee joint. In a valve-open state of the solenoid switching valve, no assisting driving force is produced. The solenoid switching valve is constructed of a solenoid switching valve having a self-holding feature, and installed in the gas passage such that a pressure difference between air chambers acts in a valve closing direction of a valve element in a predetermined period during which the solenoid switching valve is closed. This arrangement effectively reduces the power consumption of the solenoid switching valve by a simple construction.

Abstract: The legged mobile robot the foot comprises a foot main body connected to each leg, a toe provided at a fore end of the foot main body to be bendable with respect to the foot main body, and a bending angle holder capable of holding a bending angle of the toe in a bendable range of the toe. In addition, a legged mobile robot control system is configured to hold the bending angle of the toe at a first time point which is a liftoff time of the leg from a floor or earlier thereof, and to release the bending angle at a second time point after the leg has lifted off the floor to restore the toe to a initial position. With this, the bending angle at the time of liftoff can continue to be held after liftoff, whereby the robot can be prevented from becoming unstable owing to the toe contacting the floor immediately after liftoff. In addition, stability during tiptoe standing can be enhanced.

Abstract: A landing shock absorbing device 18 disposed in a foot mechanism 6 of a leg of a robot, wherein an inflatable bag-like member 19 (a variable capacity element) is provided at a ground-contacting face side of the foot mechanism 6. The bag-like member 19 is constructed of an elastic material such as rubber and has a restoring force. An interior portion of the bag-like member 19 is communicated with the atmosphere side through a flow passage 20. During a landing motion of the leg, the bag-like member 19 makes contact with the ground to be compressed, and the air in the interior portion thereof flows out into the atmosphere through the flow passage 20, so that its outflow resistance is generated. Accordingly, a landing shock is reduced. In a lifting state of the leg, the restoring force of the bag-like member 19 allows the bag-like member 19 to be inflated while the air flows into the interior portion thereof.

Abstract: An assist device is provided with a spring device that generates an auxiliary driving force, by an elastic energy, acting on a joint of a leg. The spring device includes a gas spring having a cylinder and a piston. Bending/stretching motion between link members and at the joint is transmitted to the spring device through a motion transmission device that includes a link arm. The spring device is provided so that the auxiliary driving force increases as a knee bending angle ? increases until the knee bending angle ? reaches a predetermined angle, and so that, once the knee bending angle ? exceeds the predetermined angle, the auxiliary driving force becomes smaller than or equal to the driving force obtaining at the predetermined angle, effectively reducing a burden on an actuator of the legged mobile robot joint.

Abstract: A leg type mobile robot (R) including an body (R2), legs (R1) each connected to the body (R2) via a first joint (12, 13), and foots (R17) each connected to an end part of the leg part (R1) via a second joint (15, 16), the foot (17) including a foot portion (61) having a lower end part having a ground area (64, 66) grounded on a floor surface, the foot portion (61) including a plate spring part (62) supporting empty weight while bending at the time of being grounded.

Abstract: A landing shock absorbing device 18 provided in a foot mechanism 6 of a leg of a robot comprises an inflatable and compressible bag-like member 19 (a variable capacity element) on a bottom face side of the foot mechanism 6. The bag-like member 19 is constructed of an elastic material such as rubber. Air in the atmosphere can flow into and out of the bag-like member 19 by inflow/outflow means 20 provided with a solenoid valve 27 and the like. In a landing state of the foot mechanism 6 and in a state immediately after the foot mechanism shifts from the landing state to a lifting state, the solenoid valve 27 is closed to maintain the bag-like member 19 in a compressed state.

Abstract: An assist device that applies an auxiliary driving force to a joint in parallel with a driving force of a joint actuator between a thigh portion and a crus portion, which are a pair of link members of a leg. The assist device generates the auxiliary driving force by use of spring device, such as a solid spring or an air spring. A member supporting a rod member connected to the spring device is provided with a device for transmitting a bending and stretching motion of the leg at the joint (a relative displacement motion between the thigh portion and the crus portion) to the spring device to generate an elastic force of the spring device, and for discontinuing the transmission of the bending and stretching motion to the spring device. This transmitting device is controlled in accordance with a gait of a robot. Thus, a burden on the joint actuator is reduced where necessary and favorable utilization efficiency of energy can be stably ensured.

Abstract: A landing shock absorbing device 18 disposed in a foot mechanism 6 of a leg of a robot, wherein an inflatable bag-like member 19 (variable capacity element) is provided at a bottom face side of the foot mechanism 6. The bag-like member 19 is constructed of an elastic material such as rubber. The air in atmosphere may flow into and out of the bag-like member 19 by inflow/outflow means 20 equipped with a solenoid valve 27, and the like. In a lifting state of the foot mechanism 6, inflow of the air into the bag-like member 19 is controlled, thereby controlling the final height of the bag-like member 19 in an inflated state to the height in response to a gait type of the robot. While properly reducing an impact load during a landing motion of the leg of a legged mobile robot depending on the gait type of the robot, stability of a posture of the robot may easily be secured, resulting in allowing a configuration to be lighter in weight.

Abstract: A landing shock absorbing device 18 provided in a foot mechanism 6 of a leg of a robot comprises an inflatable and compressible bag-like member 19 (a variable capacity element) on a bottom face side of the foot mechanism 6. The bag-like member 19 is constructed of an elastic material such as rubber. Air in the atmosphere can flow into and out of the bag-like member 19 by inflow/outflow means 20 provided with a solenoid valve 27 and the like. In a landing state of the foot mechanism 6 and in a state immediately after the foot mechanism shifts from the landing state to a lifting state, the solenoid valve 27 is closed to maintain the bag-like member 19 in a compressed state.

Abstract: A landing shock absorbing device 18 disposed in a foot mechanism 6 of a leg of a robot, wherein an inflatable bag-like member 19 (a variable capacity element) is provided at a ground-contacting face side of the foot mechanism 6. The bag-like member 19 is constructed of an elastic material such as rubber and has a restoring force. An interior portion of the bag-like member 19 is communicated with the atmosphere side through a flow passage 20. During a landing motion of the leg, the bag-like member 19 makes contact with the ground to be compressed, and the air in the interior portion thereof flows out into the atmosphere through the flow passage 20, so that its outflow resistance is generated. Accordingly, a landing shock is reduced. In a lifting state of the leg, the restoring force of the bag-like member 19 allows the bag-like member 19 to be inflated while the air flows into the interior portion thereof.

Abstract: An assist device is provided with a spring device that generates an auxiliary driving force, by an elastic energy, acting on a joint of a leg The spring device includes a gas spring having a cylinder and a piston. Bending/stretching motion between link members and at the joint is transmitted to the spring device through a motion transmission device that includes a link arm. The spring device is provided so that the auxiliary driving force increases as a knee bending angle &thgr; increases until the knee bending angle &thgr; reaches a predetermined angle, and so that, once the knee bending angle &thgr; exceeds the predetermined angle, the auxiliary driving force becomes smaller than or equal to the driving force obtaining at the predetermined angle. Thus, a burden on an actuator of the joint of a legged mobile robot is effectively reduced, thereby ensuring favorable utilization efficiency of energy and miniaturization of the spring device.

Abstract: An assist device that applies an auxiliary driving force to a joint in parallel with a driving force of a joint actuator between a thigh portion and a crus portion, which are a pair of link members of a leg. The assist device generates the auxiliary driving force by use of spring device, such as a solid spring or an air spring. A member supporting a rod member connected to the spring device is provided with a device for transmitting a bending and stretching motion of the leg at the joint (a relative displacement motion between the thigh portion and the crus portion) to the spring device to generate an elastic force of the spring device, and for discontinuing the transmission of the bending and stretching motion to the spring device. This transmitting device is controlled in accordance with a gait of a robot. Thus, a burden on the joint actuator is reduced where necessary and favorable utilization efficiency of energy can be stably ensured.

Abstract: In a biped mobile robot having at least a body and two leg links connected to the body, a parallel linkage is provided between the body and the two leg links such that each of the two leg links are movable relative to the body in a direction of the gravity axis. More specifically, the parallel linkage is composed of upper and lower links and right and left links each connected to the upper and lower links, and the body is connected to the upper and lower links through first and second fulcrums, while the two leg links are each connected to the right and left links. An actuator is provided at the second fulcrum to move the two leg links relative to the body in the gravity axis. Moreover, the body is connected to the parallel linkage through a joint such that the body is movable relative to the two leg links around the gravity axis.

Abstract: In a biped walking robot having a body and two articulated legs each connected to the body and each having a foot at its free end such that the robot is controlled to walk by landing a heel of the foot first on a floor. The heel of the foot has projections and packings charged in gaps. The projections are constituted to have high rigidity against forces acting in the direction of the gravity axis and low rigidity, which is lower than the first rigidity, against forces acting in other directions, when the heel is landed, thereby enabling to achieve an optimum balance between absorption/mitigation of shock at footfall and attitude stabilization after footfall.