JP2008093822A - Multi-point ground-contact type leg part support mechanism, two-foot walking robot provided with it and its control structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multi-point ground-contact type leg part support mechanism with excellent reliability capable of being easily attached to a sole of a leg part of an existing two-foot walking robot or the like, certainly and passively sliding a movable claw part of a sole support part according to a recession/projection of a ground-contact surface of a road surface or the like, quickly and certainly multi-point-supporting the sole even on the ground-contact surface with a level difference by braking the motion of the sole support part by detecting ground-contact of the fixed claw part and a movement amount of the movable claw part, and avoiding falling. <P>SOLUTION: The multi-point ground-contact type leg part support mechanism is provided with a base part arranged on the sole of the leg part of the walking robot; and the sole support part for multi-point-supporting the base part. The sole support part is provided with the three or more of movable claw parts having lower ends arranged so as to be projected to below a bottom surface of the base part and slidably retained so as to be each independently upwardly moved at ground-contact; a movement amount detection sensor part for detecting the movement amount of the respective movable claw parts; and a lock mechanism for braking the motion of all movable claw parts based on the movement amount of the movable claw parts detected by the movement amount detection sensor part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a multipoint grounding type foot support mechanism that forms a virtual support polygon in the plane of the sole and supports the sole at multiple points, a leg portion of a biped robot including the same, and a control method therefor It is about.

In recent years, research and development of humanoid robots that are active in human living environments, so-called humanoid robots, have been extensively conducted. Humanoid robots are often used not only for industrial production, but also for the purpose of making human life comfortable, such as housework and elderly care, and are in close contact with unspecified users in an environment created for humans. In order to work, it is necessary to have a form and function suitable for it. Moreover, it is required to provide a safe and flexible interface without requiring special use training, and there are a great many research subjects. In particular, bipedal walking robots that have two legs as a means of movement and that perform bipedal walking, like humans, have been extensively studied and developed by many research institutions and companies.
(Patent Document 1) filed by the present applicant includes “a base portion, a right foot portion and a left foot portion, a plurality of passive joints disposed on each of the base portion, the right foot portion and the left foot portion, and a base portion. Parallel disposed between the passive joint provided and the passive joint disposed on the right foot, and between the passive joint disposed on the base and the passive joint disposed on the left foot. And a lower body module of a biped walking robot provided with a link mechanism unit ”.
In addition, the same applicant filed (Patent Document 2) “a biped walking robot device that sets a target zero moment point at the foot and calculates a moment compensation trajectory of the waist according to the set target zero moment point. A walking pattern creation device that creates a walking pattern of "."

The lower body module of the biped walking robot described in (Patent Document 1) is configured to have a leg portion with a parallel link mechanism, so that the leg portion can withstand a heavy load, and can carry heavy objects. It is excellent and can be mounted or incorporated with a heavy upper body, and has a high degree of freedom in design. By providing the walking pattern creation device described in (Patent Document 2), walking that makes stable biped walking A pattern can be created, and the walking motion is particularly stable on a flat ground surface.
However, each foot has a flat ground contact surface, such as a place with a lot of unevenness that cannot be penetrated by a wheel-moving robot that can move at high speed and has high energy efficiency, or a place that cannot secure the wide support base required for a multi-legged robot. In places where it is difficult to do so, the rigid flat soles adopted by many conventional biped robots support many soles when they step on a projection at the center of the sole. There is a problem that it is unpredictable how the square is formed, and the fall cannot be avoided.
Even if the support polygon can be predicted, it is difficult to continue stable walking because the area of the formed support polygon is small, and swinging increases as the walk continues. There was a problem of lack of walking stability and reliability due to falling.

Therefore, the present applicant has intensively studied to achieve further improvement in the stability of operation and activities in various terrain, and completed the invention of Patent Document 3.
(Patent Document 3) states that “a base part disposed on the sole of the leg of the walking robot and an end projecting downward from the bottom surface of the base part and independently move upward at the time of ground contact”. Three or more sole support parts supported slidably or pivotably, a grounding sensor disposed on the base part or each sole support part to detect grounding of each sole support part, and a base part A multipoint grounding type foot support mechanism including a lock mechanism that brakes the motion of all the foot support portions when the ground contact sensor detects the ground contact of all the foot support portions is disclosed.
JP 2003-291080 A JP 2004-82223 A WO2006 / 011577

However, the above conventional techniques have the following problems.
(1) The multipoint grounding type foot support mechanism described in (Patent Document 3) can be easily attached to the sole of an existing biped robot or the like, and each foot support is passively provided on the road surface or the like. By following the unevenness of the ground contact surface and braking the movement of the sole support portion when all the foot support portions are in contact with the ground, it is possible to quickly support the soles at multiple points even on the ground contact surface with steps. It is a multipoint grounding type foot support mechanism that can avoid falling and is excellent in reliability. Detection failure may occur, and there is a problem that operation stability is lacking.
(2) When the ground contact sensor detects the contact of all the foot support portions, the lock mechanism locks all the foot support portions. For example, all the foot support portions of one foot portion are convex. Since the ground contact surface that is placed on the part is locked at a position higher than the height (reference position) of the other sole, there is a difference in the height of the left and right soles. It had a problem that it could not be handled. In addition, when the road surface has a concave portion, the tip of the sole support portion cannot reach the concave portion, and there is a problem that it moves to a standing leg without being locked and cannot cope with the concave road surface.
(3) In particular, when the plantar support part serving as a support point is a rotation type, a side slip occurs at the distal end part of the sole support part at the time of ground contact, so when the distal end part lands on the end of the convex part, At the same time, it has the disadvantage that the tip part slides down from the convex part, and has the problem that the adaptable topography is limited and lacks versatility.
(4) In addition, in the terrain where the vertical movable range is narrow and the difference in unevenness is large in the rotation type sole support part, it may not be possible to reliably ground all the sole support parts. Since the bottom support portion is not locked and the sole cannot be supported, the posture becomes unstable, or a fall occurs, which causes a problem of lack of operational stability and versatility.
(5) Furthermore, in the pivot type sole support portion, a side slip must occur when following the road surface, so that a friction material having a large friction coefficient cannot be used at the tip portion, and the road surface on the stance side. Insufficient frictional force between the robot and the robot can be obtained. It had the problem of becoming stable.
(6) Further, when all the foot support portions are movable, the number of parts is increased, the structure is complicated, failure and malfunction are likely to occur, and there is a problem that handling and reliability are lacking. .

  The present invention solves the above-described conventional problems, and can be easily attached to the bottom of a leg of an existing bipedal walking robot or the like, and the movable claw of the bottom support is passively connected to a road surface or the like. It can slide reliably following the unevenness of the ground, and by detecting the amount of movement of the fixed claw part and the movement of the movable claw part and braking the movement of the sole support part, Provide a multipoint grounding type foot support mechanism that can quickly and surely support multiple points of the bottom of the foot and can avoid toppling, and has a complex structure with unevenness and steps. Providing leg control of biped walking robot equipped with multipoint grounding type foot support mechanism with excellent stability and stability of walking motion that can maintain a stable posture even in terrain, and its control The purpose is to provide a structure.

In order to solve the above problems, a multipoint grounding type foot support mechanism, a leg portion of a biped robot equipped with the same, and a control method therefor have the following configurations.
According to a first aspect of the present invention, there is provided a multipoint grounding type foot support mechanism including a base disposed on a sole of a leg of a walking robot, and a sole support that supports the base at multiple points. A multi-point grounding type foot support mechanism, wherein the bottom support portion is slidably held so that the lower end protrudes below the bottom surface of the base and moves upward independently at the time of ground contact. Based on the movement amount of the movable claw portion detected by the movement amount detection sensor unit, the movement amount detection sensor unit that detects the movement amount of each of the three or more movable claw portions, And a lock mechanism that brakes the movement of the movable claw portion.
This configuration has the following effects.
(1) Three or more slidably held at the lower end projecting below the bottom surface of the base disposed on the sole of the leg of the walking robot and moving upward independently at the time of ground contact By having a movable claw part, the stroke is longer than that of a rotating type sole support part, the degree of freedom with respect to unevenness can be improved, and it is possible to reliably prevent side slipping or slipping off from a convex part. This is excellent in the stability of walking motion of the walking robot.
(2) Each movable claw portion that is slidably held on the base portion passively moves in the direction in which the amount of protrusion from the sole (the bottom surface of the base portion) decreases along the unevenness of the ground surface (slid upward). Therefore, based on the movement amount of the movable claw part detected by the movement amount detection sensor part, the movement of all the movable claw parts is braked by the lock mechanism, so that the foot contact has a wide area equivalent to a flat grounding surface. Thus, a virtual support polygon can be formed and supported at multiple points, the legs of the walking robot can be reliably supported, and a fall can be avoided.
(3) By having the movement amount detection sensor part for detecting the movement amount of each movable claw part, the grounding of the movable claw part can be confirmed with certainty, and the movement of the sole support part is ensured by the lock mechanism. Since it can be braked, the base of the sole at the time of grounding can always be held almost horizontally, and along with this, the position and posture of the torso and waist of the walking robot can be controlled as set, Excellent walking stability.
(4) Since the movable claw portion is slidably held on the base, each of the lower ends of the movable claw portion is in contact with the ground surface such as the road surface (when standing), regardless of the unevenness of the ground surface. The movable claw part can be easily and reliably slid above the sole, and the sole does not slide off the convex part of the grounding surface, and the movement of all the movable claw parts is reliably braked by the lock mechanism. It is possible to form a support polygon having the same area as the flat ground contact surface on the sole, and the support stability is excellent.
(5) Since the sole support portion is disposed at the base portion, the sole support portion and the base portion can be handled integrally, and can be easily attached to the sole of the leg portion of an existing walking robot for walking motion. Stability can be improved, and assembly workability and versatility are excellent.
(6) Since there are three or more movable claws, it is possible to form a support polygon having the same area as the flat ground contact surface on the sole of the foot and to support multiple points. Can be stably supported, and can be preferably used particularly for a biped robot.
(7) Since the movable claw portion of the sole support portion is a sliding type that slides in the vertical direction, side slip does not occur at the distal end portion of the movable claw portion at the time of ground contact. Using a friction material with a large coefficient of friction, sufficient frictional force can be obtained at the foot support part on the stance leg side, and the walking robot rotates around the yaw axis by the inertial force of the leg part on the free leg side during walking. This makes it possible to achieve stable walking.

Here, the outer shape of the base is a substantially rectangular shape, a substantially hexagonal shape, a substantially octagonal shape, or a substantially circular shape so that a sufficient support area can be secured according to the size of the sole of the leg of the walking robot, It is formed in a substantially elliptic shape. An aluminum alloy is preferably used as the base material. This is because it is lightweight and has high strength and rigidity.
At the base, a 6-axis force sensor for detecting the reaction force from the ground contact surface such as the floor or road surface and measuring the position of ZMP (Zero Moment Point) is installed and attached to the foot of the leg of the walking robot It is done.

The movable claw portion is formed in various shapes such as a substantially cylindrical shape or a substantially elliptical column shape, or a polygonal column shape such as a triangular column shape, a quadrangular column shape, or a hexagonal column shape. The movable claw portion only needs to be slidably supported with respect to the base portion, but the one that slides downward by its own weight or an urging means such as a compression spring at the time of the free leg is preferably used. . As a result, the maximum stroke can always be ensured before the movable pawl is grounded, and when the lower end of the movable pawl projecting downward from the bottom surface of the base contacts the ground surface such as the road surface (when standing) The movable claw portion can be reliably moved upward so as to reduce the amount of protrusion from the sole, and the leg portion can be supported following the unevenness of the ground contact surface. When a ball retainer, a linear bearing, or the like is provided on the sliding portion, the sliding motion can be smoothed by reducing friction, and the operation stability of the movable claw portion is excellent.
When the movable claw parts are arranged at equal intervals on the same circumference so that the positions of the respective movable claw parts are equidistant from the center of the base, the support polygon formed by the movable claw parts is an equilateral triangle or Since it becomes a regular polygon such as a square, the leg portions can be uniformly supported by each movable claw portion, and the stability at the time of contact can be improved.
The base may be provided with a fixed claw in addition to the movable claw. For robots that require high rigidity when walking, the grounding rigidity of the sole can be increased by using a fixed claw that is strong and does not deform, reducing the possibility of falling. This is because it can.

The movement amount detection sensor unit may be any unit that can detect the movement amount of the sole support unit. For example, a linear encoder is preferably used. In the case of a wire-type linear encoder, if the wire is stretched in parallel with the sole support portion and the wire slides along with the sole support portion, the movement of the sole support portion depends on the amount of wire withdrawal (movement amount). The amount can be detected. By setting the midpoint of the stroke of the sole support portion as the reference position, it is possible to deal with unevenness of the ground contact surface. The reference position can be arbitrarily set, and the timing of locking by the locking mechanism can be selected as appropriate.
Since the amount of movement of each movable claw part can be detected directly by the movement amount detection sensor unit, the height of the left and right soles, the amount of movement of each movable claw part at each sole, By measuring the time required to reach a preset reference position (height), etc., the unevenness of the ground plane can be judged, and stable continuous walking corresponding to the uneven surface while maintaining the reference position It is possible to improve versatility and stability of walking motion.

A tip contact portion formed of a friction material made of synthetic rubber or the like may be disposed at the lower end of the movable claw portion. Thereby, the frictional force with the ground contact surface can be increased, and the walking motion can be stabilized by suppressing the rotation around the yaw axis during walking. Specifically, chloroprene rubber having excellent durability is preferably used as the material of the friction material, but a hard material having a Shore hardness of about 90 is preferable in order to minimize the influence of elastic deformation.
If the tip contact part is detachably attached to the movable claw part, select a tip contact part of a different material according to the hardness or surface condition of the grounding surface, or replace the worn tip contact part. It is excellent in versatility and maintainability.

  As a lock mechanism, an actuator is driven in accordance with a signal from the movement detection sensor unit, and a brake unit such as a cam is slid or rotated by the actuator, and an inclined surface formed on the upper end or side surface of the movable claw unit. A member that abuts the brake part on the abutment surface and performs mechanical fixation or fixation by frictional force is preferably used. When locking is applied only when the lower end of the movable claw is grounded and the movable claw is loaded, the sole starts to rise and the movable claw is lowered by its own weight or urging means. Since the lock is automatically released, a drive unit for driving the movable claw portion is unnecessary, and the size and weight can be reduced. The brake unit is separately driven by an actuator and returns to the initial position.

When the adaptive grounding type claw unit with the movable claw unit, movement detection sensor unit, and lock mechanism as a unit is detachable from the base, it can be repaired or replaced by removing only the adaptive grounding type claw unit that has failed. It is easy to maintain and has excellent maintainability. In addition, each unit can be replaced with a fixed claw part where the claw part does not expand and contract as needed, so the combination and arrangement of the adaptive grounding type claw part (movable claw part) and the fixed claw part can be arbitrarily selected. Excellent versatility.
This multi-point grounding type foot support mechanism can be easily attached to the foot of an existing walking robot, and by having three or more movable claws, a support polygon can be reliably formed on each sole. Since it can be point-supported, it is particularly useful for biped robots that walk in places with severe irregularities that cannot be invaded by wheel-moving robots, or where it is impossible to secure the wide support base required for multi-legged robots. However, it can be attached to a multi-legged walking robot such as four or six legs, a work table, or the like.

Invention of Claim 2 is the multipoint grounding type foot part support mechanism of Claim 1, Comprising: The said movement amount detection sensor part is any one said movable nail | claw of all the said movable claw parts. When the movement amount of the part reaches the set value, the lock mechanism brakes the movements of all the movable claw parts.
With this configuration, in addition to the operation of the first aspect, the following operation is provided.
(1) When the movement amount detection sensor unit detects that the movement amount of any one of the movable claw parts has reached the set value, the lock mechanism performs the movement of all the movable claw parts. Because it brakes, when walking on a concave road surface, all the movable claws are grounded, and when the amount of movement of the movable claws grounded to the reference surface reaches the set value, all the movable claws are locked The movable claw part is not locked at a position higher than the reference position (height), and can stably walk while maintaining the sole at the preset reference position (height). Excellent walking reliability.

Here, each movable claw portion slides upward along the unevenness of the ground surface. However, when walking on a ground surface having a recess, first, a certain movable claw portion first contacts the reference surface of the ground surface, and then continues. The other movable claws will be grounded to the recess, but if all the movable claws are locked when all the movable claws are grounded as in the prior art, the locking timing depends on the depth of the recess. It will change and the height of the foot will vary. Even if all the movable claws are grounded, they are not locked, and when it is detected that the amount of movement of any one of the movable claws has reached the set value, it is always possible to lock all the movable claws. The sole can be supported at a reference position (height) at an equal distance from the reference surface of the ground contact surface.
The set value can be arbitrarily selected. However, when the intermediate point of the stroke of the movable claw portion is set as the reference position and ½ of the stroke of the movable claw portion is set as the set value, the unevenness with respect to the reference plane is set. It is preferable because both can be handled equally.

A third aspect of the present invention is the multipoint grounding type foot support mechanism according to the first or second aspect, wherein each of the movable claw portions is formed to expand downward from the upper end side. A cam having an elliptical arc-shaped contact surface that contacts the inclined surface of each of the movable claw portions, and an actuator for rotating the cam in a vertical plane. It has a configuration.
With this configuration, in addition to the operation of the first or second aspect, the following operation is provided.
(1) Each movable claw portion has an inclined surface formed by expanding downward from the upper end side, and an elliptical arc-shaped contact surface where the lock mechanism abuts on the inclined surface of each movable claw portion And an actuator for rotating the cam in the vertical plane, so that the cam contact surface can be brought into contact with the inclined surface of the movable claw portion simply by rotating the cam by the actuator of the lock mechanism. Thus, the upward movement of the movable claw portion can be surely prevented, and the multi-point support by the sole support portion can be performed to stably support the leg portion.
(2) Since the inclined surface of the movable claw portion is formed to expand downward from the upper end side and the contact surface of the cam is formed in an elliptical arc shape, depending on the amount of movement of the movable claw portion, By changing the rotation angle, the cam contact surface can be reliably brought into contact with the inclined surface of the movable claw portion, and the operation stability of the lock mechanism is excellent.
(3) By arranging the actuator so that the cam rotates in the vertical plane, the installation space of the lock mechanism can be narrowed, the space is excellent, and the multipoint grounding type foot support mechanism is Smaller and lighter can be achieved.

Here, as the actuator, it is sufficient that the cam can be rotated, but a rotary solenoid or a stepping motor having a high response speed is preferably used.
The rotary solenoid can instantaneously rotate the cam from the initial position and can lock the cam contact surface against the inclined surface of the movable claw portion. The stepping motor can be instantaneously locked by rotating the cam following the sliding of the movable claw portion and keeping the gap between the inclined surface of the movable claw portion and the contact surface of the cam always small. In particular, the rotary solenoid is preferable because it is small and lightweight, and is excellent in space saving and handling.
In addition, according to the stroke of the movable claw part, the inclination angle of the inclined surface of the movable claw part, the shape of the contact surface of the cam of the lock mechanism, the distance between the movable claw part and the rotating shaft of the cam, etc. should be selected as appropriate. Can do.

According to a fourth aspect of the present invention, there is provided a multipoint grounding type foot support mechanism comprising a base disposed on a sole of a leg of a walking robot, and a sole support that supports the base at multiple points. A multi-point grounding type foot support mechanism, wherein the foot support portion includes at least one fixed claw portion fixedly projecting at a lower end below the bottom surface of the base portion, and below the fixed claw portion. Three or more claw parts including one or more movable claw parts that are slidably held and project upward when grounded, a ground sensor part that detects grounding of the fixed claw part, and the ground sensor part And a lock mechanism that brakes the movement of all the movable claw portions when the grounding of the fixed claw portion is detected.
This configuration has the following effects.
(1) One or more fixed claws fixedly projecting at the lower end below the bottom surface of the base disposed on the sole of the leg of the walking robot, and projecting downward from the fixed claws and upward when grounded By having three or more claw parts including one or more movable claw parts that are slidably held so as to move, a combination of the fixed claw part and the movable claw part forms a support polygon on the sole. It can be point-supported, and the leg of the walking robot can be reliably supported corresponding to various ground contact surfaces, and can be prevented from falling.
(2) Since the lower end of the movable claw portion that is slidably held on the base protrudes downward from the lower end of the fixed claw portion, the movable claw portion contacts the ground before the fixed claw portion. The movable claw part can be grounded even at a position lower than the grounding point of the part, and when the grounding sensor part detects the grounding of the fixed claw part, the movement of all the movable claw parts can be reliably braked by the lock mechanism A support polygon having the same area as the flat ground contact surface can be formed on the sole together with the fixed claw portion, and the support stability is excellent.
(3) Since the sole support portion is disposed at the base portion, the sole support portion and the base portion can be handled integrally, and can be easily attached to the sole of the leg portion of an existing walking robot for walking motion. Stability can be improved, and assembly workability and versatility are excellent.
(4) By having three or more claw parts, it is possible to form a support polygon having the same area as the flat ground contact surface on the sole and to support the multipoint, so that the legs of the walking robot can be It can be stably supported, and can be suitably used particularly for a biped robot.
(5) Since the movable claw portion of the sole support portion is a sliding type that slides in the vertical direction, no side slip occurs at the distal end portion of the movable claw portion at the time of ground contact. Using a friction material with a large coefficient of friction, sufficient frictional force can be obtained at the foot support part on the stance leg side, and the walking robot rotates around the yaw axis by the inertial force of the leg part on the free leg side during walking. This makes it possible to achieve stable walking.
(6) Since the lower end of the movable claw portion held slidably on the base protrudes downward from the lower end of the fixed claw portion, the movable claw portion is grounded before the fixed claw portion. The movable claw part can be grounded at a position lower than the ground contact point of the part, and if it is used in combination with the control of the foot posture on the road surface, even if the movable claw part has only one place, it is surely flat on the sole. A support polygon having the same area as the ground contact surface can be formed, and a mechanism with excellent support stability can be constructed at low cost, resulting in excellent mass productivity.
(7) By combining fixed claw parts that are theoretically superior in rigidity and reliability than the movable claw parts, the number of movable claw parts can be reduced, and a mechanism with excellent support stability can be realized with high rigidity. In addition, it is difficult to cause malfunctions and has excellent handling, reliability, and support stability.

Here, the base portion, the movable claw portion, and the lock mechanism are the same as those in the first aspect, and thus description thereof is omitted.
The number of the claw portions may be three or more in total including the fixed claw portion and the movable claw portion, and the combination of the number and arrangement of the fixed claw portions and the movable claw portions is appropriately selected depending on the unevenness of the ground contact surface. be able to. By reducing the number of movable claws, the structure and control of the multipoint grounding type foot support mechanism can be simplified, failure and malfunction are unlikely to occur, and handling and reliability are excellent. In particular, when the control method of the biped walking robot device walking according to the unevenness as disclosed in WO2007 / 032120 and this multipoint grounding type foot support mechanism are used in combination, there are unevenness with few movable claws. The adaptability to the ground plane can be improved, and it is excellent in versatility and mass productivity.

As the grounding sensor, a sensor that is disposed at the grounding end of the fixed claw portion and detects the grounding between the fixed claw portion and the grounding surface is used.
As the grounding part of the grounding sensor, a push button type in which a pin protruding from the sensor surface directly contacts the grounding surface for switching or a leaf spring whose one end is rotatably supported on the sensor surface is used. There is a hinge lever type or the like in which the other end abuts on the grounding surface and swings to contact the contact on the sensor surface to perform switching. In the case of the hinge lever type, it is preferable to form or arrange a protrusion on the grounding surface side at the end on the side in contact with the grounding surface. Thereby, the edge part of a leaf | plate spring can be contact | abutted to a grounding surface more reliably, a leaf | plate spring can be rock | fluctuated, and it is excellent in stability of switching operation | movement.

The legs of the biped walking robot provided with the multipoint grounding type foot support mechanism according to claim 5 of the present invention are respectively disposed on the left and right feet and the soles of the left and right feet. The multipoint grounding type foot support mechanism according to any one of Items 1 to 4 is provided.
This configuration has the following effects.
(1) Since the multipoint grounding type foot support mechanism is disposed on the soles of the left and right foot parts, the multipoint grounding type foot support mechanism of the foot part that is grounded during walking among the left and right foot parts. This makes it possible to form a virtual support polygon with the same area as the flat contact surface on the sole of the ground, even on complex contact surfaces with irregularities and steps, and to support multiple points. It is possible to reliably support the leg portion, and it is possible to avoid a fall and continue stable walking.
(2) When performing ZMP control of a biped robot, the ground contact surface is usually assumed to be a horizontal flat surface, and the walking pattern is set so that the ZMP exists within the support polygon. On the flat sole, if the inclined surface or uneven surface of the ground contact surface is stepped on, the support polygon recognized by the biped robot will greatly differ from the actual support polygon, resulting in unstable walking However, the movable claw part of the sole support part passively follows the grounding surface and makes contact with the ground so that the biped robot recognizes even if the grounding surface is uneven. Since the supporting polygon can be made to substantially coincide with each other at all times, stable walking can be performed according to the set walking pattern.

Here, the leg part of the biped walking robot has a serial link mechanism part or a parallel link mechanism part. The parallel link mechanism portion is disposed between the passive joint disposed on the base portion and the passive joint disposed on the left and right feet, respectively. When each parallel link mechanism is arranged in a V-shape with two links as one set, and it is configured with a Stewart platform with three sets, it has excellent stability and rigidity and simplifies operation control. can do.
There are various types of links, such as those having a feed screw mechanism using a motor, linear motion links using hydraulic pressure, hydraulic pressure, pneumatic cylinders, linear motion actuators, etc., and those in which two or more rod-shaped members are connected by a drive joint. Is used. In addition, when a linear motion link is used, each linear motion link expands and contracts in the axial direction, so that it is possible to reduce the size of the apparatus without interfering with each other.
As the passive joint, a universal joint, a ball joint, a biaxial shaft joint, or a combination of these and a monoaxial or biaxial shaft joint is appropriately disposed on the base side or the left and right feet, respectively. In addition, when a universal joint is used, since a movable range becomes wide compared with a ball joint, it is preferable.

The leg control structure of the biped robot according to claim 6 of the present invention includes a left and right foot, and a multipoint grounding type foot support mechanism respectively disposed on the soles of the left and right feet. The multi-point grounding type foot support mechanism is provided with a lower end projecting from the sole, and is passively slid independently at the time of grounding to reduce the projecting amount. A claw portion, a movement amount detection sensor portion that detects a movement amount of each movable claw portion, and a lock mechanism that fixes each movable claw portion, and walks by moving the left and right foot portions up and down. A control structure of a biped walking robot that detects the amount of movement of each of the movable claw portions for each of the left and right foot portions by the movement amount detection sensor unit of the multipoint grounding type foot support mechanism. The movement of all the movable claws is braked by the lock mechanism based on the movement amount. The sole of the foot that is grounded and has a structure in which multi-point support.
This configuration has the following effects.
(1) For each of the left and right foot parts, the movement amount of each movable claw part of the multipoint grounding type foot part support mechanism is detected by the movement amount detection sensor part, and all the movable parts are moved by the lock mechanism based on the movement amount. By braking the movement of the nail part and forming a virtual support polygon on the sole of the grounded foot part to support multiple points, it is possible to improve the stability of the walking motion of the biped robot Falling can be prevented.

A leg control structure for a biped robot according to claim 7 of the present invention includes a left and right foot, and a multipoint grounding type foot support mechanism respectively disposed on the soles of the left and right feet. The multi-point grounding type foot support mechanism has at least one fixed claw portion fixed at a lower end protruding from the sole, and protrudes downward from the fixed claw portion to passively slide at the time of grounding. Three or more claw parts including one or more movable claw parts that move and reduce the amount of protrusion, a grounding sensor part that detects grounding of the fixed claw part, and a lock that fixes each of the movable claw parts And a control structure of a biped walking robot that walks by moving the left and right foot parts up and down, and the grounding of the multipoint grounding type foot support mechanism for each of the left and right foot parts The sensor unit detects the grounding of each of the fixed claw parts, and the lock is based on the grounding of the fixed claw part. Brake the movement of all the movable claw portion by structure has a configuration for multi-point supporting the sole of the foot that is grounded.
This configuration has the following effects.
(1) For each of the left and right foot parts, the grounding sensor part detects the grounding of the fixed claw part of the multipoint grounding type foot part support mechanism, and the lock mechanism based on the grounding of the fixed claw part causes all the movable claw parts to By braking the movement, it is possible to support multiple points by forming a virtual support polygon with three or more nail parts on the sole of the grounded foot part, and improve the stability of walking motion. It is possible to prevent the biped robot from falling.
(2) The lower end of the movable claw portion slidably held on the base portion protrudes downward from the lower end of the fixed claw portion, thereby walking in accordance with the unevenness as disclosed in WO2007 / 032120. When the control method of the foot walking robot device and this multipoint grounding type foot support mechanism are used in combination, adaptability to uneven grounding surfaces can be improved with few movable claws, making it versatile and mass-productive. Excellent.

As described above, according to the multipoint grounding type foot support mechanism of the present invention, the leg of the biped walking robot including the same, and the control method thereof, the following advantageous effects can be obtained.
According to invention of Claim 1, it has the following effects.
(1) The lower end protrudes downward from the bottom surface of the base disposed on the sole, and has three or more movable claw portions that are slidably held and move upward independently at the time of ground contact. Therefore, the movable claw part can be reliably slid according to the unevenness of the ground contact surface, and it is possible to reliably prevent side slipping and slipping from the convex part, and is excellent in walking robot's walking motion stability. The amount of movement of each movable claw part is detected by the movement amount detection sensor part, and the movement of all the movable claw parts is braked by the lock mechanism, thereby making the virtual area of the same area as the flat ground contact surface on the sole. A multipoint grounding type foot support mechanism with excellent support stability and operational stability that can support multiple points by forming a stable support polygon, can reliably support the legs and avoid falls Can be provided.
(2) By detecting the amount of movement of each movable claw with the movement amount detection sensor unit, it is possible to reliably check the grounding of all the movable claw units, and the movement of all the movable claw units with the lock mechanism. Excellent stability of walking motion that can be reliably controlled to keep the base of the sole in contact with the ground at all times, and to control the position and posture of the torso and waist of the walking robot. In addition, a multipoint grounding type foot support mechanism can be provided.
(3) Since the sole support portion disposed on the base can be handled integrally with the base, it can be easily attached to the bottom of the leg of an existing walking robot, and the walking motion of the walking robot Thus, it is possible to provide a multipoint grounding type foot support mechanism that is excellent in assembly workability and productivity.

According to invention of Claim 2, in addition to the effect of Claim 1, it has the following effects.
(1) When the movement amount detection sensor unit detects that the movement amount of any one of the movable claw parts has reached the set value, the lock mechanism performs the movement of all the movable claw parts. By braking, all the movable claws can be locked based on the amount of movement of the movable claws grounded to the reference plane after all the movable claws are grounded when walking on the concave road surface. It is possible to provide a multipoint grounding type foot support mechanism excellent in walking reliability on a concave road surface capable of stably walking while maintaining the sole at a preset reference position (height). it can.

According to invention of Claim 3, in addition to the effect of Claim 1 or 2, it has the following effects.
(1) By simply rotating the cam with the actuator of the lock mechanism, the cam contact surface can be brought into contact with the inclined surface of the sole support portion to reliably prevent the movable claw portion from moving upward, It is possible to provide a multipoint grounding type foot support mechanism with excellent reliability and reliability that can support the legs stably by performing multipoint support by the sole support section.
(2) The inclined surface of the movable claw portion is formed to expand downward from the upper end side, and the contact surface of the cam is formed in an elliptical arc shape so that it can be moved regardless of the amount of movement of the movable claw portion. It is possible to provide a multipoint grounding type foot support mechanism that is excellent in operational stability of a lock mechanism that can reliably contact the contact surface of the cam with the inclined surface of the claw portion.
(3) Compact, lightweight and space-saving multipoint grounding type foot support that can reduce the installation space of the lock mechanism by arranging the actuator to rotate the cam in the vertical plane. A mechanism can be provided.

According to invention of Claim 4, it has the following effects.
(1) One or more fixed claws fixedly projecting at the lower end below the bottom surface of the base disposed on the sole, and slidably projecting downward from the fixed claws and moving upward at the time of ground contact By having three or more claw parts including one or more movable claw parts that are held, the movable claw part is reliably grounded before the fixed claw part regardless of the unevenness of the grounding surface. The fixed claw part and the movable claw part are detected by detecting the grounding of the fixed claw part by the grounding sensor part and braking the movement of all the movable claw parts by the lock mechanism. Support stability that can support multiple points by forming a virtual support polygon with the same area as the flat ground contact surface on the sole, and can support the legs reliably and avoid falling In addition, a multipoint grounding type foot support mechanism having excellent operational stability can be provided.
(2) Since the sole support portion disposed on the base can be handled integrally with the base, it can be easily attached to the bottom of the leg of an existing walking robot, and the walking motion of the walking robot Thus, it is possible to provide a multipoint grounding type foot support mechanism that is excellent in assembly workability and productivity.
(3) Since the lower end of the movable claw portion that is slidably held on the base portion protrudes downward from the lower end of the fixed claw portion, the two feet walking along the unevenness as disclosed in WO2007 / 032120 When used together with the control method of a walking robot device and this multipoint grounding type foot support mechanism, adaptability to uneven grounding surfaces can be improved with few movable claws, and it is excellent in versatility and mass productivity. In addition, a multipoint grounding type foot support mechanism can be provided.

According to invention of Claim 5, it has the following effects.
(1) Since the multipoint grounding type foot support mechanism is disposed on the soles of the left and right foot parts, the multipoint grounding type foot support mechanism of the foot part that is grounded during walking among the left and right foot parts. This makes it possible to form a virtual support polygon with the same area as a flat contact surface on the sole even on complex contact surfaces with irregularities and steps, and to support the legs with multiple points. Therefore, it is possible to provide a leg portion of a biped walking robot provided with a multipoint grounding type foot support mechanism that is excellent in stability during walking and that can avoid a fall.

According to invention of Claim 6, it has the following effects.
(1) For each of the left and right foot portions, the movement amount of each sole support portion of the multipoint grounding type foot support mechanism is detected by the movement amount detection sensor unit, and all the movements are detected by the lock mechanism based on the movement amount. The movement of the foot support part is braked, and a virtual support polygon can be formed on the bottom of the grounded foot part to support the multipoint, and the leg part of the biped walking robot can be reliably supported. It is possible to provide a leg control structure of a biped walking robot that is excellent in stability of walking motion.

According to invention of Claim 7, it has the following effects.
(1) For each of the left and right foot portions, the grounding sensor portion detects the grounding of the fixed claw portion of the multipoint grounding type foot support mechanism, and the lock mechanism is used to detect all the movable claw portions based on the grounding of the fixed claw portion. Braking motion, forming a virtual support polygon on the bottom of the grounded foot, and supporting it at multiple points. Stability of walking motion that can reliably support the leg of a biped robot It is possible to provide a leg control structure of a biped robot excellent in performance.

(Embodiment 1)
A multipoint grounding type foot support mechanism according to Embodiment 1 of the present invention will be described below with reference to the drawings.
FIG. 1 is a perspective view showing a multipoint grounding type foot support mechanism according to Embodiment 1 of the present invention.
In FIG. 1, 1 is a multipoint grounding type foot support mechanism 1 according to Embodiment 1 of the present invention, and 2 is a multipoint grounding type foot support mechanism 1 made of a metal such as an aluminum alloy and having a substantially rectangular outer shape. The base 2a is formed in a substantially circular shape at the center of the base 2, and a six-axis force sensor (not shown) for detecting the reaction force from the ground contact surface such as the floor or road surface and measuring the position of the ZMP is fixed. The force sensor fixing part 2b of the base 2 is formed in two positioning holes 2c, which are drilled on the surface of the force sensor fixing part 2a and through which positioning pins for positioning the 6-axis force sensor are inserted. Four bolt insertion holes, through which fixing bolts that are drilled at symmetrical positions of the positioning hole 2b of the force sensor mounting portion 2a and that fix the six-axis force sensor by screwing are inserted, 2d are the bottom surface of the base 2, 2e Is erected on the bottom surface 2d radially on the outer periphery of the force sensor mounting portion 2a. The rib 2 of the base portion 2 that reinforces the surface 2d, 3 is a sole support portion of the multipoint grounding type foot support mechanism 1 that supports the base portion 2 by four movable claws 4 to be described later, 3a is a sole support portion 3 The attachment part 3b for attaching the movable claw part 4 to the base part 2 is slid on the multipoint grounding type foot support mechanism 1 fixed to the attachment part 3a and slidably supporting the movable claw part 4 in the vertical direction. The support part 4 is a sliding part 4a formed in the shape of a long flat plate and is slidably supported by the sliding support part 3b. The multi-point grounding has a lower end protruding below the bottom surface 2d of the base part 2. The movable claw portion 4b of the mold foot support mechanism 1 is disposed on the surface of the sliding portion 4a and has an inclined surface 4c that is formed to expand downward from the upper end side. 4d is a synthetic rubber friction material (snowshoe on a snowy day) and is formed at the lower end of the contact portion 4b. The tip end contact portions 4e and 4f of the movable claw portion 4 that are detachably disposed are disposed so as to sandwich the upper end portion of the sliding portion 4a from both sides, and the sliding claw portion 4 has a sliding support portion 3b that slides when the movable claw portion 4 slides. A stopper part that abuts on the upper end part to prevent the movable claw part 4 from coming off, 4g is a wire fixing part provided on a side part of the stopper part 4f, and 5 is a side part of the movable claw part 4 provided with a movable claw. 5a is a wire type linear encoder body of the movement amount detection sensor unit 5 and 5b is a movable claw from the wire type linear encoder body 5a. A wire 5c that is stretched in parallel with the portion 4 and slides along with the movable claw portion 4 is formed in an annular shape at the tip of the wire 5b and is inserted into the wire fixing portion 4g. Multi-point grounding type foot support mechanism 1 for braking motion 6a is an actuator of the lock mechanism 6 using a rotary solenoid, 6b is a rotation shaft of the actuator 6, 7 is a cam of the lock mechanism 6 inserted in the rotation shaft 6b and rotated in a vertical plane, Reference numeral 8 denotes an adaptive grounding claw part of the multipoint grounding type foot support mechanism 1 in which the movable claw part 4, the movement amount detection sensor part 5, and the lock mechanism 6 are unitized and detachably disposed at the four corners of the base part 2. .

The base 2 has a force sensor fixing portion 2a to which a 6-axis force sensor is fixed, and a positioning pin for positioning the 6-axis force sensor is inserted through the surface of the force sensor fixing portion 2a 2 Since the four bolt insertion holes 2c through which the fixing bolts for fixing the positioning holes 2b and the six-axis force sensor by screwing are inserted are drilled, the force sensor fixing portion 2a can be easily subjected to the six-axis force. The sense sensor can be positioned and fixed. As a result, the multipoint grounding type foot support mechanism 1 can be attached to the foot of an existing biped robot or the like via the 6-axis force sensor, and the reaction force from the grounding surface such as the floor or the road surface is detected. The position of the ZMP can be measured.
By simply changing the shapes of the base 2 and the force sensor fixing portion 2a, the multipoint grounding type foot support mechanism 1 can be attached to the feet of various shapes of biped walking robots and the like, which is excellent in versatility.

Next, details of the movable claw portion of the sole support portion and the lock mechanism will be described.
FIG. 2A is a cross-sectional side view of the main part showing the movable claw part and the locking mechanism of the sole support part, and FIG. 2B is a cross-sectional side view of the main part showing the fixed state of the movable claw part of the sole support part. FIG.
In FIG. 2, 7a is an elliptical arc-shaped contact surface of the cam 7 that contacts the inclined surface 4c of the movable claw portion 4, and 20 is a ground surface such as a road surface.
In this embodiment, as a combination of the sliding support portion 3b and the sliding portion 4a, a commercially available LM guide with a ball retainer made of THK is used, and the abutting portion 4b having the inclined surface 4c on the surface of the sliding portion 4a. To provide a movable claw portion 4. Thereby, the sliding part 4a can be smoothly moved with respect to the sliding support part 3b. When the movable claw part 4 slides downward due to its own weight at the time of the free leg and becomes the maximum length, it is possible to always ensure the maximum stroke before the movable claw part 4 contacts the ground, and protrudes downward from the bottom surface 2d of the base part 2. When the lower end of the movable claw 4 contacts the grounding surface 20 such as the road surface (when standing), the movable claw 4 can be reliably moved upward so that the amount of protrusion from the sole decreases. The legs can be supported following the unevenness of the ground plane 20.
The movable claw portion 4 is not limited to the present embodiment, and may be supported slidably with respect to the base portion 2. Moreover, you may form the sliding part 4a and the contact part 4b integrally.

By disposing the tip contact portion 4d formed of a synthetic rubber friction material at the lower end of the movable claw portion 4, it is possible to increase the frictional force with the ground contact surface 20, and to rotate around the yaw axis during walking. Suppressed and stabilized walking motion.
In this embodiment, in order to minimize the influence of elastic deformation, chloroprene rubber having a hardness of about 90 shore hardness and excellent durability is used. However, the material of the tip contact portion 4d is limited to this. is not.
In addition, by disposing the tip contact portion 4d so as to be detachable with respect to the movable claw portion 4, it is possible to select the tip contact portion 4d of a different material depending on the hardness or surface state of the grounding surface 20 or wear it. The tip contact portion 4d can be easily replaced, and is excellent in versatility and maintainability.

As shown in FIG. 1, since the insertion portion 5c at the tip of the wire 5b is inserted and fixed to the wire fixing portion 4g disposed on the side of the stopper portion 4f at the upper end of the movable claw portion 4, The wire 5b slides up and down together with the movable claw portion 4. The movement amount detection sensor unit 5 can detect the movement amount of the movable claw unit 4 by measuring the amount of drawing (movement amount) of the wire 5b from the wire linear encoder body 5a. By setting the intermediate point of the stroke of the movable claw portion 4 as the reference position, the movable claw portion 4 can move up and down by half of the stroke around the reference position, and corresponds to the unevenness of the ground plane 20. Can do.
The movement amount detection sensor unit 5 is not limited to the present embodiment, and may be any device that can detect the movement amount of the movable claw unit 4. In addition, since the reference position can be arbitrarily set, the timing of locking by the lock mechanism 6 can be appropriately selected according to the depth of the concave portion, the height of the convex portion, etc. on the ground contact surface 20. Can cope with terrain.

The lock mechanism 6 drives the actuator 6 a in accordance with a signal from the movement detection sensor unit 5, rotates the cam 7 by the actuator 6 a, and abuts the contact surface 7 a of the cam 7 on the inclined surface 4 c of the movable claw unit 4. Thus, the movable claw portion 4 can be fixed like a wedge. By locking the lower end of the movable claw portion 4 only when the lower end portion is grounded and the movable claw portion 4 is loaded, the sole begins to rise and the movable claw portion 4 moves downward due to its own weight. It slides and the lock is automatically released. The cam 7 is separately driven by the actuator 6a and returned to the initial position.
By making the adaptive grounding type claw part 8 unitizing the movable claw part 4, the movement amount detecting sensor part 5 and the lock mechanism 6 detachable with respect to the base 2, only the adaptive grounding type claw part 8 in which a problem has occurred is provided. It can be removed and repaired or replaced, and it is easy to maintain. Further, since the unit can be replaced with a fixed claw part in which the movable claw part 4 does not expand and contract as required, the combination and arrangement of the adaptive grounding type claw part 8 and the fixed claw part can be arbitrarily selected. Excellent versatility.
The number and arrangement of the movable claw portions 4 are not limited to the present embodiment, and the number of the virtual claw portions 4 is virtually the same as the flat ground surface on the sole of the foot by three or more movable claw portions 4. What is necessary is just to be able to form a square and be able to support multiple points.

The details of the operation of the multipoint grounding type foot support mechanism according to Embodiment 1 of the present invention configured as described above will be described below.
Attention is paid to a set of adaptive grounding type claws 8 of the multipoint grounding type foot support mechanism 1.
In FIG. 2A, when the base portion 2 is lowered, the tip contact portion 4 d of the movable claw portion 4 comes into contact with the ground plane 20. In FIG. 2B, when the base 2 is further lowered, the movable claw portion 4 is moved upward, and the movement amount at this time is detected by the movement amount detection sensor portion 5 (see FIG. 1), and the movement amount detection sensor portion. The movement amount signal from 5 is sent to a control unit (not shown) through a wiring (not shown).
The control unit that receives the movement amount signal from each movement amount detection sensor unit 5 brakes the movement of the movable claw unit 4 to the actuator 6a of the lock mechanism 6 when the movement amount reaches a preset value. To instruct that state.
By rotating the rotation shaft 6b of the actuator 6a, the contact surface 7a of the cam 7 comes into contact with the inclined surface 4c of the movable claw portion 4 to prevent the movable claw portion 4 from being lifted up. Brakes movement.
By braking the movement of all the movable claws 4, the four-point grounding of the sole forms a substantially rectangular support polygon, and the legs can be reliably supported at multiple points.

As described above, since each movable claw portion 4 operates independently, each movable claw portion 4 can operate according to the unevenness or inclination of the ground contact surface 20. At this time, since the movement amount detection sensor unit 5 can directly detect the movement amount of each movable claw portion 4, the height of the left and right soles and the movement amount of each movable claw portion 4 at each sole Can be determined by measuring the time required to reach a preset reference position (height), etc., and the unevenness of the ground plane 20 can be judged, and the uneven position can be handled while maintaining the reference position. Thus, stable continuous walking can be performed, and versatility and stability of walking motion can be improved.
Further, the multipoint grounding type foot support mechanism 1 can be easily attached to the foot of an existing walking robot, and the support claw part 4 reliably forms a support polygon on each sole and supports the multipoint. Therefore, it is particularly useful for a biped robot that walks in a place with a rough surface that cannot be invaded by a wheel-moving robot or a place where a wide support base surface necessary for a multi-legged robot cannot be secured. It can also be attached to multi-legged walking robots such as legs and six legs, work tables, and the like.

The legs of the biped walking robot provided with the multipoint grounding type foot support mechanism in Embodiment 1 of the present invention configured as described above will be described with reference to the drawings.
FIG. 3 is a perspective view showing a leg part of a biped walking robot provided with a multipoint grounding type foot part support mechanism in Embodiment 1 of the present invention, and FIG. 4 is a perspective view of a main part of a base part passive joint. FIG. 5 is a perspective view of a main part of the foot passive joint.
In FIG. 3, 10 is a leg part of a biped walking robot provided with the multipoint grounding type foot part supporting mechanism 1 in Embodiment 1 of the present invention, 11 is a base part of the leg part 10 of the biped walking robot, 12a, 12b is a substantially triangular shape and the left and right feet of the biped walking robot 10 with the multipoint grounding type foot support mechanism 1 disposed on the sole, and 13 is a set of two linear motion links 13a and 13b. The parallel link mechanism part 14 of the leg part 10 of the biped walking robot arranged in a V-shape as a pair is arranged symmetrically with respect to each other at three locations on the left and right sides of the base part 11. The base part passive joint having two degrees of freedom connected to the upper end of the link mechanism part 13, 15 is arranged symmetrically with respect to each of the left and right foot parts 12a, 12b, and is provided at the lower end of the three sets of parallel link mechanism parts 13. With 3 degrees of freedom linked to A foot passive joint.

In FIG. 4, 16a is a U-shaped base part upper joint fixed to the lower part of the base part 11, 16b is an upper joint shaft erected on the opposite side of the base part upper joint 16a, and 16c is linear motion. A U-shaped base lower joint 16d fixed to the upper ends of the links 13a and 13b, 16d is installed on the opposite side of the base lower joint 16c and pivotally supports the base lower joint 16c. A lower joint shaft 16e is a connecting rotation portion that connects the upper joint shaft 16b and the lower joint shaft 16d so as to be orthogonal to each other.
In FIG. 5, 17a is a U-shaped first foot upper joint connected to the lower end of the linear link 13a, and 17b is a U-shaped second foot connected to the lower end of the linear link 13b. The upper part joint 17c is installed on the opposite sides of the first foot upper joint 17a and the second foot upper joint 17b, which are suspended from both sides, and the first foot upper joint 17a and the second foot. An upper joint shaft that connects the upper joints 17b and pivotally supports them, 17d is a U-shaped foot lower joint that is connected to the foot parts 12a and 12b via a base that will be described later, and 17e is a lower foot part. A lower joint shaft erected on the opposite side erected on both sides of the joint 17d, 17f is a connecting rotary portion that connects the upper joint shaft 17c and the lower joint shaft 17e orthogonally, and 18 is on the feet 12a and 12b. The fixed joint fixing part, 18a is the lower part of the foot relative to the joint fixing part 18. Hands 17d are joint rotation shaft for rotatably supported.

As shown in FIG. 4, the base lower joint 16c rotates with respect to the base upper joint 16a in the circumferential direction of the upper joint shaft 16b and the lower joint shaft 16d. As a result, the base passive joint 14 has two degrees of freedom in the circumferential direction of the upper joint shaft 16b and the lower joint shaft 16d perpendicular to the longitudinal direction of the linear motion links 13a and 13b, and therefore the linear motion link 13a (13b). It is possible to follow the expansion and contraction of the body and smoothly follow it without hindering it and perform a walking motion.
Further, as shown in FIG. 5, the first foot upper joint 17a and the second foot lower joint 17b are arranged in the circumferential direction of the upper joint shaft 17c and the lower joint shaft 17e with respect to the foot lower joint 17d. To turn. Further, the foot lower joint 17d rotates with respect to the joint fixing portion 18 in the axial direction of the joint rotation shaft 18a. Thereby, the foot passive joint 15 has two degrees of freedom in the axial circumferential direction of the upper joint shaft 17c and the lower joint shaft 17e orthogonal to the longitudinal direction of the linear motion links 13a and 13b, and the linear motion links 13a and 13b. Since there is one degree of freedom in the axial direction of the joint rotation shaft 18a in the axial direction, it is possible to follow the expansion and contraction of the linear motion links 13a and 13b and smoothly follow it without hindering the walking motion.

Each parallel link mechanism 13 is arranged in a V shape with two linear motion links 13a and 13b as one set, and is constituted by a Stewart platform in which three sets are provided. In addition to being excellent in rigidity, it is possible to simplify the operation control. By using the linear motion links 13a and 13b as the links of the parallel link mechanism section 13, the linear motion links 13a and 13b expand and contract in the axial direction so that they do not interfere with each other. It has become.
As the base passive joint 14 and the foot passive joint 15, a universal joint, a ball joint, a biaxial joint, or a combination of these and a monoaxial or biaxial joint can be used. In addition, when a universal joint is used, since a movable range becomes wide compared with a ball joint, it is preferable.
The parallel link mechanism portions 13 used for the left and right legs are arranged symmetrically on both sides of the base portion 11, and the linear motion links 13a and 13b used for the parallel link mechanism portion 13 are also respectively left and right leg portions. Similarly, they were arranged symmetrically.

The control structure of the biped walking robot provided with the multipoint grounding type foot support mechanism in Embodiment 1 of the present invention configured as described above will be described with reference to the drawings.
FIG. 6 is an enlarged side view of the foot portion showing a walking state of the biped walking robot provided with the multipoint grounding type foot support mechanism in Embodiment 1 of the present invention.
In FIG. 6, 20 a is a concave portion of the ground plane 20.
The biped walking robot 10 provided with the multipoint grounding type foot support mechanism 1 on each of the left and right foot portions 12a and 12b has the same structure as that of the multipoint grounding type foot support mechanism 1 for each of the left and right foot portions 12a and 12b. The movement amount of the movable claw portion 4 is detected by a movement amount detection sensor portion 5 (see FIG. 1), and the movement of all the movable claw portions 4 is braked by the lock mechanism 6 based on the movement amount.

  Each movable claw portion 4 slides upward along the unevenness of the ground surface 20, but when walking on the ground surface 20 having the recess 20a, first, one movable claw portion 4 of one foot portion 12a The grounding surface 20 is grounded to the reference surface (surface), and then the other movable claw portion 4 is grounded to the concave portion 20a. However, when all the movable claw portions 4 are grounded as in the prior art, all the movable claw portions 4 are grounded. If the nail | claw part 4 is locked, the timing of a lock will change with the depth of the recessed part 20a, and the height of a leg part will vary. Therefore, even if all the movable claws 4 are grounded, the movement amount detection sensor unit 5 does not lock, and any one of the movable claws 4 out of all the movable claws 4 of the one foot 12a does not lock. When it is detected that the amount of movement has reached the set value L, the lock mechanism 6 is configured to brake the movement of all the movable claws 4. As a result, all the movable claw portions 4 can be locked when the amount of movement of the movable claw portion 4 (right side in FIG. 6) grounded to the surface of the ground contact surface 20 as the reference surface reaches the set value L. The height of the foot 12a can be maintained at a preset reference position (height), and stable walking can be performed even on the ground contact surface 20 having the recess 20a.

As described above, the multipoint grounding type foot support mechanism according to Embodiment 1 has the following operations.
(1) The lower end protrudes below the bottom surface 2d of the base 2 provided on the sole of the leg of the walking robot, and is held slidably so as to move independently independently at the time of ground contact. By having the four movable claws 4, the stroke is longer than that of the rotation type sole support portion, the degree of freedom with respect to the unevenness can be improved, and side slipping and slipping from the convex portion are surely prevented. The walking robot has excellent stability in walking motion.
(2) Each movable claw portion 4 slidably held on the base portion 2 passively follows the unevenness of the ground surface 20 in a direction in which the amount of protrusion from the sole (the bottom surface 2d of the base portion 2) decreases. Since it moves (slides upward), the movement of all the movable claw parts 4 is braked by the lock mechanism 6 based on the movement amount of the movable claw part 4 detected by the movement amount detection sensor part 5, thereby A virtual support polygon (quadrangle) with the same area as the flat ground contact surface 20 can be formed on the bottom to support multiple points, so that the legs of the walking robot can be reliably supported, It can be avoided.
(3) By having the movement amount detection sensor unit 5 that detects the movement amount of each movable claw portion 4, the grounding of the movable claw portion 4 can be confirmed reliably, and the lock mechanism 6 Since the movement can be reliably braked, the base 2 of the sole at the time of grounding can be held substantially horizontally at the same time, and the position and posture of the torso and waist of the walking robot are controlled accordingly. It is excellent in stability of walking motion.
(4) Since the movable claw portion 4 is slidably held on the base portion 2, when the lower end portion of the movable claw portion 4 contacts the ground surface 20 such as a road surface (when standing), the unevenness of the ground surface 20 Regardless of this, each movable claw portion 4 can be easily and surely slid above the sole, and the sole does not slide off the convex portion of the grounding surface 20, and all the movable claw portions 4 can be moved by the lock mechanism 6. The movement of the claw portion 4 can be reliably braked, and a support polygon having the same area as the flat ground contact surface 20 can be reliably formed on the sole, and the support stability is excellent.
(5) Since the sole support portion 3 is disposed on the base portion 2, the sole support portion 3 and the base portion 2 can be handled integrally, and can be easily attached to the bottom of the leg portion of an existing walking robot. The stability of walking motion can be improved, and the assembly workability and versatility are excellent.
(6) By having the four movable claws 4, it is possible to form a support polygon having the same area as the flat ground contact surface 20 on the sole of the foot and to support the multipoint, so that the leg of the walking robot It is possible to support the part stably, and it can be preferably used particularly for a biped robot.
(7) Since the movable claw portion 4 of the sole support portion 3 is a sliding type that slides in the vertical direction, no side slip occurs at the distal end portion of the movable claw portion 4 at the time of ground contact. By using a friction material having a large friction coefficient as the material of the contact portion 4d, a sufficient frictional force can be obtained between the movable claw portion 4 on the standing leg side and the ground contact surface 20, and the leg on the free leg side during walking. The walking robot does not rotate around the yaw axis due to the inertial force of the part, so that stable walking can be realized and the reliability is excellent.
(8) When the movement amount detection sensor unit 5 detects that the movement amount of any one of the movable claws 4 has reached the set value, the lock mechanism 6 detects all the movable claws. By braking the movement of the portion 4, when moving on the concave road surface, all the movable claw portions 4 are grounded, and the moving amount of the movable claw portion 4 that is grounded to the reference surface (the surface of the ground surface 20) is a set value. By locking all the movable claw portions 4 when reaching the position, the movable claw portion 4 is not locked at a position higher than the reference position (height), and the foot is set at a preset reference position (height). The bottom can be maintained and stable walking can be performed, and the walking reliability on the concave road surface is excellent.
(9) Each movable claw portion 4 has an inclined surface 4c formed to expand downward from the upper end side, and the lock mechanism 6 contacts the inclined surface 4c of each movable claw portion 4. Since the cam 7 having the elliptical arc-shaped contact surface 7a and the actuator 6a for rotating the cam 7 in the vertical plane are provided, the cam 7 is simply rotated by the actuator 6a of the lock mechanism 6. The contact surface 7a is brought into contact with the inclined surface 4c of the movable claw portion 4 so that the movable claw portion 4 can be prevented from moving upward. It can be supported stably.
(10) The inclined surface 4c of the movable claw portion 4 is formed so as to expand downward from the upper end side, and the contact surface 7a of the cam 7 is formed in an elliptical arc shape. Accordingly, by changing the rotation angle of the cam 7, the contact surface 7 a of the cam 7 can be surely brought into contact with the inclined surface 4 c of the movable claw portion 4, and the operation stability of the lock mechanism 6 is excellent.
(11) By disposing the actuator 6a so that the cam 7 rotates in the vertical plane, the installation space of the lock mechanism 6 can be reduced, the space saving property is excellent, and the multipoint grounding type foot portion is provided. The support mechanism 1 can be reduced in size and weight.

The legs of the biped walking robot provided with the multipoint grounding type foot support mechanism in Embodiment 1 have the following actions.
(1) Since the multipoint grounding type foot support mechanism 1 is disposed on the soles of the left and right foot portions 12a and 12b, the foot portion 12a (left and right foot portions 12a and 12b) that are grounded during walking 12b), the multipoint grounding type foot support mechanism 1 forms a virtual support polygon having the same area as the flat grounding surface 20 on the sole even in a complicated grounding surface 20 with unevenness and steps. Thus, it is possible to support multiple points, to reliably support the leg portion 10 of the biped robot, and to avoid a fall and continue stable walking.
(2) When performing ZMP control of a biped robot, the ground contact surface is usually assumed to be a horizontal flat surface, and the walking pattern is set so that the ZMP exists within the support polygon. In the flat sole, if the inclined surface or unevenness of the ground contact surface 20 is stepped on, the support polygon recognized by the biped robot will be greatly different from the actual support polygon, and the walking will become unstable and the final will be However, if the movable claw part 4 of each sole support part 3 is passively grounded along the grounding surface 20, the bipedal walking robot can be moved even if the grounding surface 20 is uneven. Since the support polygon to be recognized and the actual support polygon can always be substantially matched, stable walking according to the set walking pattern can be performed.

According to the control structure of the legs of the biped robot in the first embodiment, the following actions are provided.
(1) For each of the left and right foot portions 12a and 12b, the movement amount of each movable claw portion 4 of the multipoint grounding type foot portion support mechanism 1 is detected by the movement amount detection sensor portion 5, and based on the movement amount. The movement of all the movable claws 4 is braked by the lock mechanism 6 and a virtual support polygon is formed on the soles of the grounded feet 12a and 12b to support the multipoint, thereby improving the stability of walking motion. It is possible to prevent the biped robot from falling over.

(Embodiment 2)
A multipoint grounding type foot support mechanism according to Embodiment 2 of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is attached | subjected to the thing similar to Embodiment 1, and description is abbreviate | omitted.
FIG. 7 is a perspective view showing a multipoint grounding type foot support mechanism according to Embodiment 2 of the present invention.
In FIG. 7, the multipoint grounding type foot support mechanism 1A of the second embodiment is different from that of the first embodiment in that the bottom support 3A is fixed with the lower end protruding below the bottom 2d of the base 2. The three fixed claw portions 4A and one movable claw portion 4 that protrudes downward from the fixed claw portion 4A and moves upward at the time of grounding are slidably held.

Next, the detail of a fixed nail | claw part is demonstrated.
FIG. 8 is a cross-sectional side view of an essential part showing a grounding sensor part of a fixed claw part of a sole support part.
In FIG. 8, 5A is a grounding sensor portion of the multipoint grounding type foot support mechanism 1A that detects the grounding of the fixed claw portion 4A.
As the ground sensor 5A, any sensor may be used as long as it is disposed at the end of the fixed claw portion 4A on the ground side and detects the ground between the fixed claw portion 4A and the ground plane 20.
In the present embodiment, as the grounding portion of the grounding sensor 5A, a push button type in which a pin protruding from the sensor surface directly contacts the grounding surface 20 to perform switching is used. However, the present invention is not limited to this. For example, a hinge lever type that performs switching by contacting the contact on the sensor surface by swinging the other end of the leaf spring supported on the sensor surface with one end pivotably contacting the ground surface. A thing etc. can be used.

Based on the operation of the multipoint grounding type foot support mechanism in the second embodiment of the present invention configured as described above, the biped walking robot provided with the multipoint grounding type foot support mechanism in the second embodiment. The control structure will be described with reference to the drawings.
FIG. 9 is an enlarged side view of the foot showing a walking state of the biped walking robot provided with the multipoint grounding type foot support mechanism in the second embodiment of the present invention. In addition, since the leg part of the biped walking robot provided with the multipoint grounding type foot part supporting mechanism in the second embodiment is the same as that in the first embodiment, the description thereof is omitted.
In FIG. 9, 20 b is a convex portion of the ground plane 20.

First, FIG. 7 shows a state in which the sole support portion 3A is in contact with a flat ground surface, but as described in the first embodiment, the movable claw portion 4 has its own weight or The maximum length is slid downward by an urging means such as a compression spring, and the lower end of the movable claw portion 4 protrudes downward from the lower end of the fixed claw portion 4A. Accordingly, the movable claw portion 4 can be grounded before the fixed claw portion 4A regardless of the unevenness of the ground surface 20.
When walking on the ground contact surface 20 having the convex part 20b, when the base part 2 of one foot part 12a is lowered from the free leg state, first, as shown in FIG. 9, the tip contact part 4d of the movable claw part 4 comes into contact. The convex part 20b of the ground 20 is contacted. When the base portion 2 is further lowered, the movable claw portion 4 is moved upward, and the fixed claw portion 4A is grounded to the ground plane 20. The grounding of the fixed claw part 4A is detected by the grounding sensor part 5A (see FIG. 8), and a signal from the grounding sensor part 5A is sent to a control part (not shown) through a wiring (not shown).
The control unit that receives the grounding signal from the grounding sensor unit 5A instructs the lock mechanism 6 to brake the movement of the movable claw unit 4 and maintain the state.
Since the operation of the lock mechanism 6 is the same as that of the first embodiment, the description thereof is omitted.
By braking the movement of the movable claw part 4 with the grounding sensor part 5A of the fixed claw part 4A, the four-point grounding of the sole forms a substantially rectangular support polygon, and the legs are reliably supported at multiple points. Can do.

  In the present embodiment, the case where the multipoint grounding type foot support mechanism 1A has one movable claw portion 4 and three fixed claw portions 4A has been described. However, the number and arrangement of the movable claw portions 4 and the fixed claw portions 4A are described. Such a combination can be appropriately selected depending on the unevenness of the ground surface 20. By reducing the number of movable claws 4, the structure and control of the multipoint grounding type foot support mechanism 1 </ b> A can be simplified, failure or malfunction is unlikely to occur, and handling and reliability are excellent. In particular, when the control method of the biped walking robot device that walks along unevenness as disclosed in WO2007 / 032120 and this multipoint grounding type foot support mechanism 1A are used in combination, the unevenness is reduced with a small number of movable claws 4. The adaptability to the ground contact surface 20 can be improved, and the versatility and mass productivity are excellent.

As described above, the multipoint grounding type foot support mechanism according to Embodiment 2 has the following operations.
(1) Three fixed claw portions 4A fixed at the lower end projecting below the bottom surface 2d of the base 2 disposed on the sole of the leg of the walking robot, and grounded by projecting downward from the fixed claw 4A By having one movable claw portion 4 that is slidably held that sometimes moves upward, a combination of the fixed claw portion 4A and the movable claw portion 4 forms a support polygon on the sole and supports it at multiple points. Therefore, it is possible to reliably support the leg portion of the walking robot corresponding to various ground contact surfaces 20, and to avoid a fall.
(2) Since the lower end of the movable claw portion 4 slidably held on the base portion 2 protrudes downward from the lower end of the fixed claw portion 4A, the movable claw portion 4 is grounded before the fixed claw portion 4A. Therefore, when the grounding sensor portion 5A detects the grounding of the fixed claw portion 4A, the movement of the movable claw portion 4 can be surely braked by the lock mechanism 6, and the sole is surely flat with the fixed claw portion 4A. A support polygon having the same area as the ground contact surface 20 can be formed, and the support stability is excellent.
(3) Since the sole support portion 3A is disposed on the base portion 2, the sole support portion 3A and the base portion 2 can be handled integrally, and can be easily attached to the bottom of the leg portion of an existing walking robot. The stability of walking motion can be improved, and the assembly workability and versatility are excellent.
(4) By having four claw portions that are a combination of three fixed claw portions 4A and one movable claw portion 4, a support polygon having a width equivalent to that of the flat ground contact surface 20 is surely formed on the sole. Therefore, the leg portion of the walking robot can be stably supported, and can be preferably used particularly for a biped walking robot.
(5) Since the movable claw portion 4 of the sole support portion 3A is a sliding type that slides in the vertical direction, no side slip occurs at the distal end portion of the movable claw portion 4 at the time of ground contact. By using a friction material having a large friction coefficient as the material of the part, a sufficient frictional force can be obtained at the foot support part 3A on the stance side, and the walking robot can be moved by the inertial force of the leg part on the free leg side during walking. Stable walking can be realized without rotating around the yaw axis.
(6) By combining the fixed claw portion 4A, which in principle is more rigid and reliable than the movable claw portion 4, the number of the movable claw portions 4 can be reduced, and the multipoint grounding type foot portion having excellent support stability The support mechanism 1A can be realized with high rigidity, failure and malfunction are unlikely to occur, and the handling, reliability, and support stability are excellent.

  According to the leg portion of the biped walking robot provided with the multipoint grounding type foot support mechanism in the second embodiment, the same action as in the first embodiment is obtained.

According to the control structure of the leg portion of the biped robot in the second embodiment, the following operation is provided.
(1) For each of the left and right foot portions 12a, 12b, the grounding of the fixed claw portion 4A of the multipoint grounding type foot support mechanism 1A is detected by the grounding sensor portion 5A, and the lock mechanism is based on the grounding of the fixed claw portion 4A. 6, the movement of the movable claw portion 4 is braked so that a virtual support polygon can be formed on the soles of the grounded foot portions 12a and 12b to support multiple points, thereby improving the stability of walking motion. It is possible to prevent the biped robot from falling over.

  The present invention can be easily attached to the sole of the leg of an existing bipedal walking robot or the like, and the movable claw part of the sole support part is slid reliably following the unevenness of the ground contact surface such as the road surface. By detecting the grounding of the fixed claw part and the amount of movement of the movable claw part and braking the movement of the sole support part, it is possible to quickly and reliably Providing a highly reliable multipoint grounding type foot support mechanism that can support the bottom with multiple points and avoid falling, and maintain a stable posture even on complex terrain with unevenness and steps Can provide a leg of a biped robot equipped with a multipoint grounding type foot support mechanism that is excellent in stability and versatility of walking motion, and a control structure thereof, Especially in places with uneven surfaces that cannot be invaded by a wheeled robot It is possible to spread the bipedal walking robot that performs walking in places that can not secure a large supporting base face required for multi-legged robot.

The perspective view which shows the multipoint grounding type foot | leg part support mechanism in Embodiment 1 of this invention. (A) Main part cross-sectional side view showing sole support part and lock mechanism (b) Main part cross-sectional side view showing braking state of sole support part The perspective view which shows the biped walking robot provided with the multipoint grounding type foot | leg part support mechanism in Embodiment 1 of this invention. Perspective view of the main part of the base passive joint Perspective view of essential parts of passive foot joint FIG. 1 is an enlarged side view of a foot showing a walking state of a biped walking robot provided with a multipoint grounding type foot support mechanism in Embodiment 1 of the present invention. The perspective view which shows the multipoint grounding type foot | leg part support mechanism in Embodiment 2 of this invention. Cross-sectional side view of the main part showing the grounding sensor part of the fixed claw part of the sole support part An enlarged side view of a foot showing a walking state of a biped walking robot provided with a multipoint grounding type foot support mechanism in Embodiment 2 of the present invention

Explanation of symbols

1, 1A Multi-point grounding type foot support mechanism 2 Base 2a Force sensor fixing part 2b Positioning hole 2c Bolt insertion hole 2d Bottom 2e Rib 3 Foot support part 3A Adaptive grounding claw part 3a Attachment part 3b Sliding support part 4 Movable claw part 4A Fixed claw part 4a Sliding part 4b Abutting part 4c Inclined surface 4d Tip contact part 4e, 4f Stopper part 4g Wire fixing part 5 Movement amount detection sensor part 5A Grounding sensor part 5a Wire type linear encoder body 5b Wire 5c Insertion part 6 Lock mechanism 6a Actuator 6b Rotating shaft 7 Cam 7a Contact surface 8 Adaptive grounding claw part 10 Biped walking robot 11 Base part 12a, 12b Leg part 13 Parallel link mechanism part 13a, 13b Direct link 14 Base part passive Joint 15 Foot passive joint 16a Upper joint of base part 16b Upper part Hand shaft 16c Lower joint shaft 16d Lower joint shaft 16e Connection rotation portion 17a First foot upper joint 17b Second foot upper joint 17c Upper joint shaft 17d Foot lower joint 17e Lower joint shaft 17f Connection rotation portion 18 Joint fixing part 18a Joint rotating shaft 20 Grounding surface 20a Concave part 20b Convex part

Claims (7)

A multipoint grounding type foot support mechanism comprising: a base disposed on a sole of a leg of a walking robot; and a sole support that supports the base at multiple points;
The foot support portion is provided with three or more movable claw portions that are slidably held so that the lower end protrudes downward from the bottom surface of the base portion and independently moves upward when touched. A movement amount detection sensor unit that detects a movement amount of the movable claw unit, and a lock mechanism that brakes the movement of all the movable claw units based on the movement amount of the movable claw unit detected by the movement amount detection sensor unit; A multi-point grounding type foot support mechanism. When the movement amount detection sensor unit detects that the movement amount of any one of the movable claws has reached a set value, the lock mechanism detects the movement of all the movable claws. The multipoint grounding type foot support mechanism according to claim 1, wherein the movement is braked. Each of the movable claw portions has an inclined surface formed to expand downward from the upper end side, and the locking mechanism is an elliptical arc contact that abuts on the inclined surface of each of the movable claw portions. The multipoint grounding type foot support mechanism according to claim 1 or 2, further comprising a cam having a surface and an actuator for rotating the cam in a vertical plane. A multipoint grounding type foot support mechanism comprising: a base disposed on a sole of a leg of a walking robot; and a sole support that supports the base at multiple points;
The sole support portion is slidably held by one or more fixed claw portions fixed at a lower end projecting downward from the bottom surface of the base portion and projecting downward from the fixed claw portion and moving upward at the time of ground contact Three or more claw parts including one or more movable claw parts, a grounding sensor part for detecting grounding of the fixed claw part, and when the grounding sensor part detects grounding of the fixed claw part, A multipoint grounding type foot support mechanism, comprising: a lock mechanism that brakes the movement of the movable claw portion. The multipoint grounding type foot support mechanism according to any one of claims 1 to 4, wherein the multipoint contact type foot support mechanism is provided on left and right foot portions and on the soles of the left and right foot portions, respectively. Legs of a biped robot. Left and right foot portions, and multipoint grounding type foot support mechanisms disposed on the soles of the left and right foot portions, respectively, and the multipoint grounding type foot portion support mechanism extends from the bottom to the bottom. 3 or more movable claw portions that are arranged so as to protrude and are passively slid independently at the time of grounding to reduce the amount of protrusion, and a movement amount detection sensor portion that detects the movement amount of each of the movable claw portions. And a lock mechanism for fixing each of the movable claw portions, and a control structure of a biped robot that walks by moving the left and right foot portions up and down, and for each of the left and right foot portions, The movement detection sensor unit of the multipoint grounding type foot support mechanism detects the movement amount of each of the movable claw parts, and the movement of all the movable claw parts is braked by the lock mechanism based on the movement amount. And the multi-point support of the sole of the grounded foot part 2 Control structure of the legs of a walking robot. Left and right foot portions, and multipoint grounding type foot support mechanisms disposed on the soles of the left and right foot portions, respectively, and the multipoint grounding type foot portion support mechanism extends from the bottom to the bottom. 3 or more including one or more fixed claws fixedly projecting and one or more movable claws projecting downward from the fixed claws and passively sliding at the time of grounding to reduce the protrusion amount Biped walking that walks by moving the left and right foot parts up and down, and a grounding sensor part that detects the grounding of the fixed claw part, and a lock mechanism that fixes each of the movable claw parts In the control structure of the robot, for each of the left and right foot parts, the grounding sensor part of the multipoint grounding type foot part support mechanism detects the grounding of each of the fixed claw parts, and the grounding of the fixed claw parts Based on the above, the foot part grounded by braking the movement of all the movable claw parts by the lock mechanism Control structure of the legs of the biped walking robot, which comprises multi-point supporting the sole.

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