JPH10277968A - Two-foots walking robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent consumption of the joint torque by providing a robot having two-foots bodies on a lower part of a body which is long along the perpendicular direction to the yaw axis of the robot to cancel the moment around the yaw axis. SOLUTION: A two-foots walking robot 1 is provided with a body 2 and a body comprising two legs on a lower part of the body. The two-foots walking robot has the yaw axis, the pit axis 5 and the roll axis 6. The body 2 has a moment canceling part 7. The moment canceling part 7 cancels the moment around the yaw axis in the two-foots walking mode by the inertia moment around the yaw axis, and is long along the direction perpendicular to the yaw axis of the two-foots walking robot 1. As for the angular arrangement of the moment canceling part 7, the longitudinal axis of the moment canceling part 7 is arranged along the roll axis 6 of the robot. The moment canceling part 7 is provided with a large mass part 8 having a large mass in the longitudinal direction. The moment around the yaw axis can be canceled to prevent consumption of the joint torque.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot provided with a walking device having two legs.

[0002]

2. Description of the Related Art As a self-supporting walking robot using legs, a multi-legged walking robot has been developed in which a plurality of legs, such as two, three, four and six legs, support the body of the robot. In these multi-legged walking robots, with the supporting legs grounded to support the weight of the torso, the free leg is moved to another point and then touched down, and such a supporting leg and the free leg are alternately placed. The robot moves and walks while supporting the weight of the body by switching.

One of the major problems that arises when conducting a walking experiment with a bipedal walking robot is how to absorb the moment about the yaw axis. This is particularly problematic for bipedal walking robots that do not have a degree of freedom on a plane parallel to the yaw axis (Front Plane). One solution to address this is to stop this movement at the ankle by inserting a damper system around the yaw axis at the ankle. When the walking speed is relatively low, even if there is no such a damper system, the shoe sole stops naturally due to friction between the sole and the ground. However, as the walking speed increases, the yaw axis moment becomes considerably large, and eventually a fall occurs.

[0004]

Therefore, it is desired to develop a technique for canceling the moment about the yaw axis. It is inevitable that one of such techniques can cancel out by swinging the inertia around the yaw axis, but this method is attractive from the viewpoint of control theory, but this method is used alone. This is undesirable because swinging a large mass consumes the joint torque accordingly.

The present invention has been made in view of the above circumstances, and can cancel the moment around the yaw axis due to structural factors of a bipedal walking robot, and therefore does not consume joint torque. It is an object of the present invention to provide a biped walking robot that can be easily implemented.

[0006]

SUMMARY OF THE INVENTION In accordance with this object, a bipedal walking robot according to the present invention is a robot having two legs under a torso, wherein the torso is connected to a yaw axis of the robot. It is characterized by forming a long body along the vertical direction.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the drawings showing an embodiment.

1 and 2, reference numeral 1 denotes a bipedal walking robot. The bipedal walking robot 1 has a torso 2 and a leg 3 composed of two legs below the torso. Biped robot 1
Is the yaw axis 4 and the pitch axis (pitc
h axis) 5, roll axis 6
Having.

The body 2 has a moment canceling portion 7.
The moment canceling unit 7 cancels the moment around the yaw axis during biped walking by the moment of inertia around the yaw axis, and has a rod-like or beam-like shape along the direction perpendicular to the yaw axis of the bipedal walking robot 1. It is shaped like a scale.

The arrangement angle of the moment canceling portion 7 is arbitrary on a plane perpendicular to the yaw axis. In particular, the longitudinal axis of the moment canceling portion 7 is arranged along the roll axis 6 of the robot. Is advantageous. Moment canceling part 7
Has large mass portions 8 with large masses at both ends in the longitudinal direction. In this embodiment, the leg 3 has one joint j (j1, j
2) and two leg members F (F1, F2) composed of one link L (L1, L2) are directly connected. Each joint j (j1, j2) is driven by a respective motor (not shown).

In the bipedal walking robot constructed as described above, of the two legs, the supporting leg is grounded and the weight of the body 2 is supported, and the free leg is moved to another point and then grounded. By alternately switching the support leg and the free leg, walking is performed while supporting the weight of the body. During this walking, a rotational moment is generated around the sole of the ground contact leg, and a yaw axis moment is generated. This yaw axis moment is canceled by the moment of inertia of the moment canceling portion 7 around the yaw axis. Further, not only the yaw axis moment but also the pitch axis moment due to disturbance is canceled.
In addition, the large mass unit 8 can be replaced with a manipulator, a power source, and the like, and can function as a body.

In the biped walking robot described above, the body may be rigid or the inertia about the yaw axis may be variable. Further, a device may be provided which cancels the moment of inertia about the yaw axis by dynamically shaking the mass. Furthermore, the moment of inertia around the pitch axis may be dynamically shaken to cancel the nonlinear characteristics of the entire walking robot.

[0013]

[Experimental Example] As shown in FIG. 3, a bipedal walking robot 1 having a torso 2 composed only of a torso main body 11 (FIG. 3b) and a book having a torso 2 composed of a torso main body 11 and a moment canceling section 7 are shown. Comparative evaluation was made with that of the invention (FIG. 3a). The body 11 has a weight of 15 kg and a moment of inertia of 0.93.
kgm ² . The moment canceling portion 7 has a length (h) of 6 cm, a width (w) of 2 cm, and a length (l) of 1.
Made of 5m A5052 material (duralumin) and weighing 4.9k
g. In this case, the moment of inertia of the moment canceling portion 7 is assumed to be 0.91 kgm ² . a has a weight increase of (4.9 / 15) × 100 = 33% compared to b, while the moment of inertia is (0.93 + 0.91) /0.93=
At 2, the ease of rotation about the yaw axis is reduced by about 1/2 due to the moment of inertia about the yaw axis.

[0014]

As is apparent from the above description, according to the present invention, the yaw axis moment can be canceled by the structural factor of the bipedal walking robot, and therefore, the embodiment can be implemented without wasting the joint torque. An easy biped walking robot can be obtained.

[Brief description of the drawings]

FIG. 1 is an explanatory plan view of a bipedal walking robot according to the present invention.

FIG. 2 is an explanatory side view of the biped walking robot according to the present invention.

FIG. 3 is an explanatory view showing two types of body structures;

[Explanation of symbols]

 Reference Signs List 1 bipedal walking robot 2 torso 3 legs 4 yaw axis 5 pitch axis 6 roll axis 7 moment canceling part 8 large mass part 11 torso main body

Claims (6)

[Claims] 1. A robot having two legs on a lower part of a torso, wherein the torso forms a long body in a direction perpendicular to a yaw axis of the robot. robot 2. The bipedal walking robot according to claim 1, wherein the body forms a long body along a roll axis of the robot. 3. The bipedal walking robot according to claim 1, wherein the torso has large mass portions at both ends in a length direction. 4. The bipedal walking robot according to claim 1, wherein the body has a rigid body or a variable inertia about a yaw axis. 5. The bipedal walking robot according to claim 1, further comprising a device for canceling the moment of inertia around the yaw axis by dynamically shaking the mass. 6. A method of dynamically canceling a moment of inertia around a yaw axis by dynamically swinging mass, and further canceling a nonlinear characteristic of an entire walking robot by dynamically swinging mass of inertia around a pitch axis. Biped Walking Robot