JP2007136601A - Moving method for gripping member, and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moving method for gripping member and apparatus, giving a large instantaneous force to a gripping member, without increasing the size of the apparatus to move an object without dragging the gripping member on the floor, by cooperatively performing take-up of a linear flexible link and swing of a robot arm, and to provide a mechanism for varying the rigidity of the link. <P>SOLUTION: By cooperatively performing pulling operation of the linear flexible link and the take-up operation of the linear flexible link, the object held by the gripping member at the tip of the linear flexible link is moved. A rigid arm is mounted on a driving joint installed on a robot body, the rigid arm is provided with a take-up means and a guide means for the linear flexible link, and a control means is provided to cooperatively perform rocking of the rigid arm and take-up of the linear flexible link. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention uses a robot mechanism having a soft chain (hereinafter referred to as “linear flexible link”) such as a string, a rope, and a wire and a gripping member attached to the tip of the chain, and grips it by the tension of the linear flexible link. The present invention relates to a method and an apparatus for moving a member. With this method and apparatus, the object can be moved by controlling the movement of the gripping member that grasps the object.

  Attention has been focused on a method using a robot as an effective means for automatically moving a target object from a certain arbitrary position to another target position using a mechanical system. In addition, the size of the geometric area (work area) where the robot can operate the target object is considered as one of the basic indicators of robot performance, especially in large spaces such as outdoor work. Then, a robot with a wider work area is required.

  In order to make the reach area of the robot as wide as possible, a mechanism in which the length of the link constituting the arm is made as long as possible is conceivable. However, since the conventional technique uses a rigid link, the longer the link, the larger the arm weight increases the load on the output of the drive source. Therefore, the longer the length of the link, the larger the drive source is required, which increases the weight of the entire robot, the higher the inertia of the link, the lower the movement speed of the arm, and the energy for the work. The problem arises that the efficiency is further reduced. Currently, the length of a robot arm developed for working outdoors is at most several meters (see a in FIG. 1).

  Next, there is a method in which a robot arm is mounted on a moving mechanism to expand the reach area of the robot. As a moving mechanism, mechanisms such as wheels, crawlers, and legs that move in contact with the ground surface have been developed, and there is a conventional technique in which a robot arm is mounted on these moving mechanisms (see b and c in FIG. 1). However, since the movement mechanism in contact with the ground surface is affected by the shape and properties of the ground surface, there is a problem that movement in rough areas such as steep slopes, depressions, and swamps is very difficult in the prior art.

  In addition, a moving mechanism represented by unmanned aircraft such as helicopters, airplanes, and airships that move without touching the surface of the earth has been developed. However, there is no practical machine that has a robot arm on this moving mechanism. Even if a robot arm is mounted on a mechanism that moves without touching the ground surface, the weight of the moving mechanism is small, the attitude control of the aircraft is difficult, and contact with the environment as represented by a crash. There are problems such as the entire system going down easily.

  Therefore, in the robot arm mechanism, a method of using a linear, variable-length, lightweight and flexible link in place of some rigid arms can be considered. For example, as shown in FIG. 1d and FIG. 2, after the rigid arm 14 is repeatedly swung to accumulate kinetic energy, the length of the linear flexible link 11 is extended from the robot body 10 to the tip. In this method, a certain gripping member 12 is projected (casting) onto a target object 13, the movement of the gripping member 12 is controlled in the air by the tension of the linear link 11, and the target object 13 is gripped. The type of mechanical system that implements this kind of method is called a “casting manipulator”). By using this method, it is possible to have a very wide reach area with a simple mechanism and compact size, and it is also energy efficient, allowing high-speed transport operations to be repeated and having excellent fault tolerance. There is an advantage of being.

Now, using the linear flexible link feeding and winding mechanism mounted on the conventional casting manipulator shown in FIG. 3, the object grasped by the gripping member mounted on the tip of the variable length linear flexible link is collected. In this case, the following problems may occur.
(1) When the linear flexible link is wound in a state where the gripping member is dragged, there arises a problem that the gripping member or the linear flexible link comes into contact with the environment. For example, when there is a hole or a step on the floor, the gripping member may be caught or the linear flexible link may be rubbed and cut at the corner of the step.
(2) When the gripping member 12 that grasps the distant object 13 is collected, in order to move the air in the air so that the gripping member 12 does not touch the floor, a sufficient upward speed that does not touch the floor and the gripping member It is necessary to give the gripping member 12 sufficient kinetic energy that 12 can reach the robot body from a distance. Therefore, when the collection is performed only with the linear flexible link winding device, the winding device is required to generate a very large force in a short time, so that the scale of the device is increased, the weight and size are increased, There are problems such as an increase in energy consumption. Further, it is difficult for the linear flexible link winding device attached to the robot body 10 to give the gripping member 12 a sufficient upward speed.
(3) When the linear flexible link 11 is pulled by shaking the rigid arm 14 and the gripping member 12 that grasps the object is moved, the output of the drive source that drives the rigid arm is saturated depending on the weight of the object and the posture of the rigid arm. Problems arise.
(4) When a gripping member is pulled with a momentary force through a linear flexible link with small expansion and contraction, energy loss occurs due to a damping effect due to the viscous characteristics of the linear flexible link. Can't give energy effectively.

According to the present invention, according to the prior art, it is necessary to generate a large force (instantaneous force) in the linear flexible link take-up drive device in order to prevent the gripping member from being caught by a step or the like on the floor. In view of the fact that it leads to an increase in scale, by operating the winding of the linear flexible link and the swing of the rigid arm in cooperation, it is possible to give a large instantaneous force to the gripping member without increasing the size of the device, Furthermore, it aims at providing the holding member moving method and apparatus which can give the upward speed which suppresses the fall of a holding member to a holding member.
Another object of the present invention is to provide an apparatus that can change the apparent rigidity of a linear flexible link. In addition, when pulling the linear flexible link, the linear flexible link is operated as if it is an elastic body by manipulating the movement of the linear flexible link using an elastic mechanism without changing the rigidity of the linear flexible link itself. In this case, the rigidity seen from the outside of the linear flexible link is called “apparent rigidity”.

(1) In order to achieve the above object, the gripping member moving method of the present invention moves the gripping member by the tension of the linear flexible link using a robot mechanism having a linear flexible link and a gripping member attached to the tip of the linear flexible link. The gripping member moving method is characterized in that the pulling operation of the linear flexible link and the winding operation of the linear flexible link are performed in a coordinated manner to move the gripping member at the tip or the object grasped by the gripping member. .
(2) Further, in order to effectively perform the pulling operation of the linear flexible link of (1) above, the rigid arm is swung in a state where the linear flexible link is slackened before performing the pulling operation. During the swing operation after generating sufficient kinetic energy, grasp the striking force through the linear flexible link with the gripping member or gripping member using the inertia of the rigid arm by suddenly pulling the linear flexible link It is characterized by giving to the object which is done.
(3) Further, the gripping member moving method of the present invention is a gripping member moving method in which a gripping member is moved by the tension of the linear flexible link using a robot mechanism having a linear flexible link and a gripping member attached to the tip of the linear flexible link. In this case, the gripping member at the tip of the linear flexible link or the object grasped by the gripping member is moved by repeating the cooperative operation of the pulling operation of the linear flexible link and the winding operation of the linear flexible link. Yes.
(4) Moreover, the gripping member moving device of the present invention is a gripping member moving device that moves the gripping member by the tension of the linear flexible link using a robot mechanism having a linear flexible link and a gripping member attached to the tip of the linear flexible link. , A rigid arm is attached to the drive joint installed in the robot body, and the rigid arm is provided with a linear flexible link feeding / winding means and a guiding means to swing the rigid arm and wind the linear flexible link. It is characterized by providing a control means for cooperatively performing taking.
(5) In addition, the gripping member moving device according to the present invention includes a brake pedestal slider mounted so as to be capable of relative movement with respect to the rigid arm and a fixed support fixed to the rigid arm in (4). An elastic member such as a spring is attached to the brake base slider, and a slide stop means for stopping the relative movement with the rigid arm and a feeding stop means for stopping the movement of the linear flexible link are attached to the brake pedestal slider. It is characterized by making the apparent rigidity of the step variable.
(6) In addition, the gripping member moving device of the present invention according to the above (4), wherein the brake pedestal slider that slides relatively freely with respect to the rigid arm and the translation drive that slides relatively with respect to the rigid arm. A slide stopping means and a linear stop for stopping relative movement with the rigid arm is mounted on the brake pedestal slider by attaching an elastic member such as a spring between the support fixed to the translation drive unit and the brake pedestal slider. It is characterized in that the apparent rigidity of the linear flexible link is made continuously variable by installing a feeding stop means for stopping the movement of the flexible link and controlling the displacement of the elastic member using the translation drive unit. Yes.
(7) The gripping member moving device according to the present invention is the above (4), wherein the brake pedestal slider capable of sliding relative to the rigid arm is mounted, and the brake pedestal slider is moved relative to the rigid arm. Equipped with slide stop means to stop the movement and feeding stop means to stop the movement of the linear flexible link, and it is driven to slide on each strut with respect to the rotating strut having the fixed strut and rotating joint provided on the rigid arm The supporting points are connected by an elastic member such as a spring, and the rotary support and the brake pedestal slider are connected by a non-expandable link, and the relative position between the supporting points is changed to change the displacement of the elastic member. By controlling, the apparent rigidity of the linear flexible link is made variable continuously by the lever principle.

The present invention has the following excellent effects.
(1) When the gripping member is projected onto the target object and the grasped target object is collected, when the linear flexible link is wound up, the gripping member is surely movable in the air, so that the gripping member and the environment are in contact with each other. Can be avoided. For example, compared to the method of moving the gripping member so as to drag the floor surface, the problem that the gripping member is caught or the linear flexible link is worn out when there is a hole or a step in the floor is solved. it can.
(2) When projecting the gripping member onto the target object and collecting the grasped target object, the cooperative operation of winding the linear flexible link and the swinging of the rigid arm is repeated, and the instantaneous force is continuously applied to the gripping member. Thus, a large kinetic energy can be given to the gripping member without causing an increase in the scale of the apparatus, an increase in weight / size, and an increase in energy consumption, and the air movement of the gripping member can be ensured.
(3) When the gripping member is moved in the air by pulling the linear flexible link in (2) above, the kinetic energy is efficiently given to the gripping member by changing the apparent rigidity of the linear flexible link. Can do.
(4) The switching of the apparent rigidity of the linear flexible link in (2) above is performed by using a brake pedestal slider that is slidable in the extending / winding direction of the linear flexible link to the rigid arm via an elastic member such as a spring. It can be realized by a simple means of providing.
(5) The apparent rigidity of the linear flexible link in (2) above is determined by providing an elastic member such as a spring between the fixed column and the rotating column connected to the linear flexible link. Can be made variable by a simple means of providing each elastic member coupling point of each column so as to be slidable.
(6) When a heavy object is lifted statically by a robot, there may be an output saturation region where the output of the actuator reaches a limit. Even when a heavy object is lifted statically by a casting manipulator, as shown in FIG. 4A, there are an output saturation region where the output of the drive joint 18 is saturated and an output non-saturation region where the output is not saturated. There is a case. However, in the casting manipulator, the kinetic energy can be accumulated by swinging the rigid arm with a small load in which the tension of the linear flexible link is zero in the output non-saturation region A as shown in FIG. After that, by making the tension of the linear flexible link in the vicinity of the boundary with the output saturation region positive, it is possible to apply a striking force to the heavy object through the linear flexible link. Therefore, the rigid arm can be lifted from the output non-saturation region A to the other output non-saturation region B from the output non-saturation region A by the speed / angular velocity of the gripping member generated by the striking force as shown in FIG. It becomes. Such an effect can also be applied to the above (2) in which the gripping member moves in the air, and the motion of the rigid arm is generated with the linear flexible link slackened before the linear flexible link is pulled. By suddenly pulling the linear flexible link in the region where the output of the driving joint is not saturated during the movement of the arm, the impact force is applied to the gripping member or the object grasped by the gripping member via the linear flexible link. It is possible to move the gripping member or the object grasped by the gripping member by pulling the linear flexible link in a state where the output is not saturated due to the generated speed and angular velocity of the gripping member.
(7) When a heavy object is lifted statically with a casting manipulator, as shown in FIG. 5A, an output saturation region where the output of the drive joint 18 is saturated and an output unsaturation region where the output is not saturated If the linear flexible link has the same expansion and contraction characteristics as the elastic body, the output non-saturation region A extends beyond the output saturation region to another output non-saturation region as shown in FIG. The rigid arm can be moved to B with a small load. Therefore, the object grasped by the gripping member that cannot be lifted statically is lifted by the restoring force of the elastic body that is stretched in a state where the rigid arm is held in the output non-saturation region B as shown in FIG. It becomes possible. Such an effect can also be applied in the above (2) in which the gripping member moves in the air. By giving the linear flexible link the same elastic property as that of the elastic body before pulling the linear flexible link, the rigid arm The rigid arm can be moved to a region where the output of the drive joint is not saturated by pulling the gripping member in a direction in which the gripping member is pulled in a state where the load is small. It becomes possible to move the grasped object.
(8) As shown in FIG. 24, not only the recovery but also the gripping member can be moved by reciprocating at high speed. Moreover, since the speed of the gripping member can be increased by this repetitive motion, it can be applied to a projecting operation of the gripping member further away. Furthermore, as shown in FIG. 25, in the state where the moving mechanism is equipped with a casting manipulator having a function of changing the apparent rigidity of the linear flexible link, and the gripping member grasps the object fixed to the environment, By coordinating the winding operation of the linear flexible link shown in (2), the swinging motion of the rigid arm, and the movement / stopping of the robot body by the moving mechanism, the above-mentioned (6) and It is possible to move the slope while suppressing the output saturation of the drive source using the effect shown in (7).

  A best mode for carrying out a gripping member moving method and apparatus according to the present invention will be described below with reference to the drawings.

FIG. 6 shows a basic operation related to gripping / recovering the target object in the operation (casting manipulation) of the gripping member by the casting manipulator, which is divided into the following five operations.
(A) Rotating operation: The entire manipulator is swung, and the movement necessary for the gripping member to reach the target object is given.
(B) Projection operation: The restraint of the linear flexible link is released at an appropriate timing, and the gripping member is projected toward the target while the linear flexible link is fed out.
(C) Trajectory control operation: Controls the position / posture of the gripping member being projected so that the target object can be grasped.
(D) Grasping operation: Grasping the target object.
(E) Recovery operation: In order to recover the grasped target object, the winding of the linear flexible link and the movement of the rigid arm are performed in cooperation.

  The present invention focuses on the recovery operation (e) above, and in order to recover the grasped target object 13, the gripping member when the winding of the linear flexible link 11 and the motion of the rigid arm 14 are performed in a coordinated manner. The present invention relates to a method and apparatus for performing twelve motion control and an apparatus for changing the apparent rigidity of a linear flexible link. Hereinafter, it demonstrates in detail based on an Example.

As shown in FIG. 6E, the cooperative operation of winding the linear flexible link and the rigid arm movement for collecting the grasped target object is performed by winding the linear flexible link 11 and the rigid arm 14. It is fundamental to apply an instantaneous force to the gripping member 12 by simultaneously swinging.
Using the winding device for the casting manipulator shown in FIG. 7 and the drive source for driving the joint 1, the pulling operation of the linear flexible link and the winding operation of the linear flexible link by swinging the rigid arm as shown in FIG. By generating a large force instantaneously in cooperation, the gripping member generates a speed necessary for movement, and the gripping member is moved in the air. However, when the load applied to the drive source of the winding device exceeds the output of the drive source when pulling the gripping member 12, the linear flexible link 11 is restrained by a brake or the like shown in FIG. It is possible to reduce the load on the source.

  If sufficient movement speed cannot be generated even by the operation shown in FIG. 8, the operation shown in FIG. 8 is repeated, and force is intermittently applied to the gripping member to generate the movement speed. For example, when collecting a distant object or a heavy object, as shown in FIG. 9, the cooperative operation of winding the linear flexible link 11 and swinging the rigid arm 14 is repeated and intermittently occurs in the gripping member 12 intermittently. By continuously applying the force, the gripping member 12 collects the object 13 while moving in the air. The number of repetitions of the cooperative operation is determined by the relationship between the object collection distance and the moving distance of the object 13 by one cooperative operation.

Next, a method for pulling the linear flexible link will be described.
The pulling method of the linear flexible link can be classified according to the “movement method” and “movement direction” of the link connected to the driving source for the pulling operation.
Considering translation and rotation as the “movement method” and reciprocation type and one-way type as the “movement direction”, they are classified as shown in FIG.
The reciprocating type shown in FIGS. 10A and 10B can pull the linear flexible link intermittently, and the one-way type shown in FIGS. 10C and 10D can be pulled continuously.

The features of the mold shown in FIG. 10 will be described.
(A) Rotating reciprocating type: As described with reference to FIG. 4, it is possible to instantaneously pull with a large force using the inertia of the slid rigid arm. In addition, in the pulling operation by the rotary reciprocating type using a long rigid arm, the upward component of the pulling force can be greatly expanded, so the upward speed of the gripping member can be given, and it is extremely difficult to move the gripping member in the air. This is an effective pulling method. However, although the linear flexible link can be pulled once, the pulling operation cannot be repeated if the linear flexible link is loosened after being pulled.
(B) Translational reciprocating type: The linear flexible link is restrained by a translational drive type brake device, and the linear flexible link is pulled and sufficiently pulled by moving the translational drive type brake device in the direction opposite to the gripping member. After this, the linear flexible link is released, and the translational drive type brake device moves in the direction of the gripping member and repeats a series of operations. Compared with the translational one-way type shown in FIG. However, the number of commercially available linear actuators is generally smaller than that of rotary actuators.
(C) Rotating one-way type: The structure is simple and compact compared to other methods, but the inertial force of the rotating part is small, so that the inertial force that can be used is smaller than the rotating reciprocating type shown in FIG. Since it is small, it is not suitable for an operation that generates a large instantaneous force intermittently. Since the inertia of the mechanism cannot be used effectively, a large output drive source is required to generate a large instantaneous force, resulting in a decrease in energy efficiency, high cost, and a large scale device. In the case of a small drive source, it is possible to continuously apply a small force to the gripping member, but since a large force cannot be generated in a short time, the speed necessary for the gripping member to reach the robot body is generated. Before grabbing, the gripping member falls to the floor.
(D) Translational one-way type: Since a long moving distance of the towing vehicle is necessary, the apparatus becomes large. In general, there are fewer types of commercially available linear actuators than rotary actuators. In the case of a wheel-type tow vehicle, problems such as slip occur.

There is also a method of performing a pulling operation by combining the four basic methods shown in FIG.
FIG. 11 shows a pulling operation by a combination of a rotary reciprocating type and a rotary one-way type. The pulling operation can be performed in cooperation with the rotary reciprocating type and the rotary one-way type. In addition, after a sufficient speed is generated in the gripping member due to the instantaneous force generated by the pulling operation, the gripping member approaches itself, so that the linear flexible link can be wound up in an unloaded state by the rotary one-way type. . If the winding of the linear flexible link is wound faster than the approaching speed of the gripping member and the linear flexible link is stretched again or close to the state, the pulling operation of the gripping member can be repeated further. The gripping member can be collected by intermittent pulling operation as shown in FIG. 9 to compensate for the disadvantage of the rotary reciprocating type that can only be pulled once.

Next, a method for efficiently applying kinetic energy to the gripping member by a pulling operation will be considered.
In general, a linear flexible link such as a wire, string, or rope has a damping effect and a spring effect in the expansion / contraction direction. FIG. 12 shows a dynamic model of the linear flexible link. As shown in FIG. 12, the linear flexible link includes not only a spring element but also a damper element (attenuating element), and part of the energy applied to the gripping member via the linear flexible link is the damper. Lost by element.

In FIG. 13, the material point and the fixed end are connected to each other using the linear flexible link without the spring and the linear flexible link with the actual spring attached, and the mass point is in a state where the linear flexible link is loosened. Shows the behavior of the mass point when the velocity in the direction indicated by the arrows shown in <1> and <1 '> in FIG. 13 is given. When the spring is not attached to the linear flexible link, the mass does not sufficiently repel due to the dissipation of energy due to the damping effect of the damper element of the linear flexible link shown in FIG.
On the other hand, in the case of a linear flexible link equipped with a spring having a very low rigidity compared to the spring element of the linear flexible link itself, the extension of the attached spring is larger than the change in the elongation of the spring element of the linear flexible link itself. Since the change is much larger, the displacement speed of the damper element shown in FIG. 12 is small and the damping effect is difficult to appear, so that the mass point bounces greatly as shown in <3 ′> and <4 ′> in FIG. In order to effectively give energy to the gripping member through the linear flexible link, it is an effective method to add the effect of the spring shown in FIG. 13 to the linear flexible link.

Further, consider the output saturation of the drive source in the pulling operation of the linear flexible link.
As described above, by adding the effect of the spring to the linear flexible link in the region where the output is statically saturated as shown in FIG. 5A, the spring is in a state where the load is small, that is, the output is not saturated. Since the rigid arm can pass through the output saturation region while stretching the object, and the object can be moved by the restoring force of the extended spring, adding the spring effect to the linear flexible link is a driving source This is an effective method for suppressing the output saturation of the.

Therefore, a method of adding a spring effect (elasticity) to the linear flexible link will be described.
(A) A method of directly connecting an elastic member to a linear flexible link as shown in FIG.
This method has a problem that the overall rigidity of the linear flexible link and the spring as the elastic member cannot be made variable. Also, as shown in FIG. 6A, when the entire manipulator is swung before the projection of the gripping member, the gripping member vibrates on the extension line of the linear flexible link due to the expansion and contraction of the spring coupled to the linear flexible link. The whole manipulator becomes a complicated swing and hinders projection control. Furthermore, since it is difficult to measure the elongation of the spring, it is difficult to control the movement of the gripping member due to the expansion and contraction of the spring.

(A) A method of indirectly adding an elastic member to the linear flexible link between the winding device and the gripping member.
As shown in FIG. 15A, the rigid arm used for guiding the linear flexible link and pulling the linear flexible link is replaced with a flexible link having elasticity equivalent to a fishing rod, and the gripping member is moved using the elasticity of the flexible link. Is the method. In this method, it is generally difficult to control the bending of the flexible link and the vibration due to the deflection of the flexible link. Therefore, when the gripping member is projected, when the linear flexible link is braked, the linear flexible link is wound. The bending / deflection of the flexible link that occurs in some cases causes control errors and vibrations, and as a result, there is a problem that it is difficult to control the movement of the gripping member in the air.
Further, in the method using a pulley and a pulley with a spring attached as shown in FIG. 15B, the spring is attached when the tension of the linear flexible link is zero in order to add a spring effect to the linear flexible link. The linear flexible link is bent by the pulley, and the pulley is arranged so that the spring contracts as the tension increases. In this method, since the linear flexible link needs to be bent along the pulley in order to give a spring effect, the higher the rigidity of the spring, the greater the influence of the friction of the pulley. As a result, a frictional force is generated in the linear flexible link, which hinders the movement control of the gripping member.

(C) A method of adding an elastic member to the winding device as shown in FIG.
Since a drive source such as a motor is generally heavier than a brake device or the like, in order to vibrate the drive unit 20 for the winding device with a spring, a spring with high rigidity is required because of a large inertial force and frictional force. Further, when the oscillating drive unit is stopped by a brake or the like, a large braking force is required because the inertial force is large.

(D) A method of adding an elastic member to the brake base 22 as shown in FIG.
Compared to the weight of the linear flexible link take-up drive source or the like, the weight of the brake 16 for stopping the feeding of the linear flexible link shown in FIG. 17 can be selected to be small. The effect of inertia is small. Further, the vibration (reciprocating motion) of the brake pedestal 22 by the spring is easily stopped by another brake or the like. Furthermore, when the linear flexible link 11 is restrained by the brake 16 and the linear flexible link 11 is pulled, the spring is pulled together with the linear flexible link 11, and the linear flexible link 11 seems to extend as if it is a spring. At this time, the apparent rigidity of the linear flexible link 11 viewed from the outside is the sum of the spring rigidity and the rigidity of the linear flexible link itself. When the linear flexible link 11 is released by the brake 16, the rigidity of the linear flexible link itself is increased. It becomes. Thus, the apparent rigidity of the linear flexible link 11 can be easily switched.

  When an instantaneous force is applied to the gripping member 12 by pulling the linear flexible link 11, if the linear flexible link 11 expands and contracts like a spring, a force can be efficiently applied to the gripping member and a pulling operation can be performed. Since the repetition cycle can be lengthened, control becomes easy. However, it is known that when a linear flexible link having a low tensile rigidity such as a spring is used, a complicated behavior in which a pendulum motion and a spring expansion / contraction motion are combined in the swing shown in FIG. Therefore, it is desired that the tensile rigidity of the linear flexible link can be adjusted. Further, when the tensile rigidity of the linear flexible link is made variable, it is desirable that the influence of the inertia of the variable device or the like on the linear flexible link is as small as possible. Based on the above, as a method of adding a spring effect to the linear flexible link, a method of restraining the linear flexible link by the brake mounted on the brake pedestal 22 connected to the spring as shown in FIG. 17 is considered effective. As shown in FIG. 18, the brake pedestal slider 23 that slides on the rigid arm and the rigid arm 14 are coupled by a spring, and a brake for stopping the slide that can stop the relative movement of the brake pedestal slider and the rigid arm is mounted on the brake pedestal slider. Consider the mechanism. When the linear flexible link 11 is constrained by the brake 16 and the linear flexible link 11 is pulled in the direction of the gripping member 12, the slide stop brake is turned on to restrict the relative movement between the brake pedestal slider 23 and the rigid arm 14, The apparent rigidity of the linear flexible link 11 is the rigidity of the linear flexible link itself. When the brake for stopping the slide is turned off and the relative movement of the brake pedestal slider 23 and the rigid arm 14 is made free, the linear flexible link 11 is made. At the same time, the spring is pulled, and the linear flexible link 11 seems to extend as if it were a spring. At this time, the apparent rigidity of the linear flexible link 11 seen from the outside is the sum of the rigidity of the spring and the rigidity of the linear flexible link itself.

In the mechanism shown in FIG. 18, the apparent rigidity of the linear flexible link cannot be continuously changed. Therefore, in order to finely control the pulling operation of the gripping member, a method of continuously changing the apparent rigidity of the linear flexible link is considered.
If the fixed post 24 of the spring of FIG. 18 is changed to a translational drive unit 28 that slides on a rigid arm as shown in FIG. 19, various spring expansion and contraction states can be created.
Before the linear flexible link is constrained by the brake 16, the brake pedestal slider and the rigid arm are constrained by the brake 27, and the translation drive unit 28 is moved to a desired position and fixed, whereby the springs are variously extended. Can be. Therefore, the desired flexible rigidity can be discretely generated in the linear flexible link by setting the spring in a desired expansion / contraction state and restraining the linear flexible link by the brake 16 and simultaneously releasing the brake 27. It becomes possible. Further, even if the translation drive unit 28 is fixed with the brake 27 released, and the linear flexible link 11 is restrained by the brake 16, the apparent rigidity of the linear flexible link can be increased even if the position of the translation drive unit 28 is changed. Can be changed continuously.

Furthermore, a method for continuously changing the spring stiffness will be described.
As shown in FIG. 20 (a), a slide support point (A) 29 that is driven to slide the fixed column, and a slide support point (B) 30 that is driven to slide the rotatable column 26 When a spring is mounted between the two, the rigidity of the rotating column 26 in the rotating direction can be made variable by lever principle by controlling the position of each supporting point on each column.
Therefore, when the joint 31 as shown in FIG. 20B is provided on the rotary support 26 in FIG. 20A and the joint 31 and the brake pedestal slider are connected by the link 32 that does not expand and contract, the slide support point (A ) 29 and (B) 30 by controlling the position, the rigidity in the translational direction of the brake pedestal slider can be made variable. Therefore, when the linear flexible link is constrained by the brake for stopping feeding, the apparent rigidity of the linear flexible link is obtained. Can be made continuously variable. The entire system shown in FIG. 20A is called a variable stiffness mechanism 33.
Now, if the slide support points (A) and (B) are set to the positions b and b ′, respectively, the same rigidity as in FIG. 17 can be generated in the brake pedestal slider. Next, when the slide support points (A) and (B) are moved to a and a ′, the rigidity at the joining point 31 is increased by the lever principle. Conversely, when the slide support points (A) and (B) are moved to c and c ′, the rigidity at the joint point 31 is reduced. When the slide support points (A) and (B) are moved so that the rigidity in this mechanism is the minimum as shown in FIG. 20 (c) and the maximum is as shown in FIG. 20 (d). It is. This is a method of making the rigidity at the output end variable by adjusting a force transmission mechanism connecting the spring and the output end. Conventionally, there is a method to change the rigidity of the spring by changing the length of the elastic part of the spring by changing the position where the spring is fixed to the fixed end. However, the characteristics of the spring are partially changed depending on the frequency of use. There's a problem. In this method, all parts of the spring are uniformly used for expansion and contraction, so there is no such problem. From the above, a method has been shown in which the apparent rigidity of the linear flexible link when the linear flexible link is restrained by a brake can be continuously varied.
As one method for determining the apparent rigidity of the linear flexible link, there is a method for determining it according to the posture of the rigid arm and the output state of the drive joint 18. For example, as shown in FIG. 5 (b), when the rigid arm is shaken and the gripping member is pulled up via the linear flexible link, the spring extends, but the rigid arm is in the output non-saturation region B shown in the upper side of FIG. 5 (c). This is a method of setting the rigidity of the spring so that the tension when the tension reaches reaches smaller than the sum of the weight of the gripping member and the weight of the object grasped by the gripping member.

FIG. 21 shows an example of a system for controlling the tensile rigidity of the linear flexible link 11.
In the figure, a rigid arm 14 is attached to the robot body 10 via a joint 18, for example, a joint that can be driven around an axis 18-1 perpendicular to the paper surface.
At the rear part of the rigid arm 14, a feeding / winding device 15 comprising a rotary drive source 20 and a drum 21 to which the rotational force of the rotary drive source 20 is transmitted via a belt is mounted.
In addition, a rotary guider 17 is provided at the front portion of the rigid arm 14, and the linear flexible link 11 pulled out from the drum 21 passes through a guide member 19, a brake pedestal slider 23 and a rotary guider 17 described later. Coupled to the gripping member 12. The rotary guider 17 is designed to be able to follow flexibly even if the direction of the linear flexible link 11 changes. For example, the rotary guider 17 has a structure that can freely rotate around an axis 17-1 perpendicular to the paper surface. It has a structure for guiding the linear flexible link 11.
A brake pedestal slider 23 is mounted on the front side of the joint 18 of the rigid arm 14 so as to be slidable with respect to the rigid arm 14. As shown in FIG. 21, the rigid arm 14 is provided with a fixed support column 24 and a rotatable rotation support column 26, and slide support points (A) 29 that are driven to slide on the support columns 29 slide support points (B). 30 is provided, and both supporting points are connected by a spring. The rotary support 26 and the brake pedestal slider 23 are coupled by a link 32 that does not expand and contract. Further, on the brake pedestal slider 23, a brake 16 that can stop the movement of the linear flexible link 11 relative to the brake pedestal slider 23 and a brake 27 that can stop the sliding of the brake pedestal slider 23 relative to the rigid arm 14 are provided. .

  In FIG. 21, for example, with the brake 27 turned off (brake not actuated, the same applies hereinafter) and the brake 16 turned on (brake actuated; the same applies hereinafter), the rigid arm 14 is shaken to move the tip of the linear flexible link 11. When the holding member 12 is pulled, the spring 25 extends and the brake pedestal slider 23 moves forward together with the linear flexible link 11, so that the linear flexible link 11 looks like a spring with low tensile rigidity. Furthermore, the apparent rigidity of the linear flexible link 11 can be continuously changed by controlling the relative position between the slide support points (A) 29 and (B) 30. When the linear flexible link 11 is wound up by the winding device 15 with the brake 16 turned off, the rigidity of the original linear flexible link 11 is restored.

The situation of air collection of the gripping member 12 will be described below with reference to FIG. The description of the gripping operation of the object 13 by the gripping member 12 is omitted here. In addition, the description of the operation of changing the apparent rigidity of the linear flexible link 11 at this time is also omitted here, so that the expansion and contraction state of the spring when the gripping member 12 is collected in the air is displayed in an easy-to-understand manner. A fixed translation drive unit 28 is used instead of the variable rigidity mechanism 33, and the display is shown in FIG.
First, with the linear flexible link 11 slightly slacked as shown in FIG. 22A, the brake 27 is turned off and the brake 16 is turned on as shown in FIGS. When shaken, the gripping member 12 is pulled by the resultant force of the striking force generated by the inertia of the rigid arm 14 and the rotational driving force of the joint 18, and the brake pedestal slider 23 restraining the linear flexible link 11 moves toward the rotary guider 17. Be pulled. Even after the swing of the rigid arm 14 is finished, the spring 25 is in an extended state, and the energy given by the swing of the rigid arm 14 is accumulated in the spring 25.
Next, as shown in FIG. 22 (d), the gripping member 12 is pulled by the contraction of the spring 25, and the energy stored in the spring 25 is efficiently converted into the kinetic energy of the gripping member 12 with a very small loss. Is done. As shown in FIGS. 5E and 5F, the brake 16 is turned off when the spring is fully contracted, and the brake 27 is turned on when the spring 25 is natural as shown in FIG. To.
Next, as shown in FIG. 5H, the linear flexible link winding device 15 is driven to swing the rigid arm 14 toward the gripping member 12 while winding the linear flexible link 11.
By repeating the above operations (a) to (h), it is possible to perform air collection of the gripping member 12 as shown in FIG.

  (A) to (h) in FIG. 23 correspond to (a) to (h) in FIG. 22 respectively, and the brake pedestal slider 23 and the spring 25 shown in FIG. 21 in each (a) to (h). The operating state of the brake 16, the brake 27, and the linear flexible link winding device 15 is shown.

It is a figure for demonstrating the outline and working area | region of the conventional manipulator comprised only by the casting manipulator and the rigid body arm. It is a whole perspective view for demonstrating the condition which grasps | collects and collect | recovers an object with the holding member attached to the front-end | tip of a variable-length linear flexible link using a casting manipulator. It is a figure which shows the principal part for grasping | ascertaining and collect | recovering an object with the holding member attached to the front-end | tip of a variable length linear flexible link using a casting manipulator. It is a figure explaining the method of passing a static output saturation area | region using the inertia of the rigid arm of a casting manipulator. It is a figure explaining the method of passing through a static output saturation area | region using the elasticity added to the linear flexible link of the casting manipulator. It is a figure explaining the basic operation | movement regarding the projection of a holding member in the operation of the holding member by a casting manipulator, and the grasping | collecting and collection | recovery of a target object. It is a figure explaining the casting manipulator provided with the joint which can drive a winding device and a rigid arm of a linear flexible link. It is a figure explaining cooperation operation of linear flexible link winding and swing of a rigid arm. It is a figure explaining the basic operation | movement which continues applying the instantaneous force to a holding member intermittently by repeating the cooperative operation | movement with linear flexible link winding-up and the swing of a rigid body arm. It is a figure explaining the basic method of pulling a linear flexible link. It is a figure explaining the pulling method of the linear flexible link which combined the rotation reciprocation type | mold and the rotation one way type | mold. It is a figure explaining the dynamic model of a linear flexible link. It is a figure explaining the behavior of the mass point to which the linear flexible link was connected. It is a figure which shows the method of connecting a spring element directly to a linear flexible link. It is a figure which shows the method of adding a spring element indirectly to a linear flexible link. It is a figure which shows the method of adding a spring element to a winding apparatus. It is a figure explaining the method of adding a spring element to a brake pedestal. It is a figure explaining an example of the mechanism which makes rigidity variable discretely. It is a figure explaining an example of the mechanism which makes a rigidity variable continuously using a translation drive part. It is a figure explaining an example of the mechanism which makes a rigidity variable continuously using a lever principle. It is the figure which showed an example of the system which controls the tensile rigidity of a linear flexible link. It is a figure explaining the condition of the air collection | recovery of a holding member. It is a figure which shows the operating state of the brake pedestal slider of FIG. 21, a spring, a brake, a brake, and a drum in each of (a)-(g) of FIG. It is a figure which shows the reciprocating motion of the holding member by cooperation of the swinging operation | movement of a rigid body arm, and the winding-up / feeding-out operation | movement of a linear flexible link. It is a figure which shows the movement of a robot main body by cooperation of the swing operation | movement of a rigid arm in the state which grasped | ascertained the fixed end of the environment with the holding member, and winding-up and drawing-out operation | movement of a linear flexible link.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Robot main body 11 Linear flexible link 12 Gripping member 13 Target object 14 Rigid arm 15 Feeding / winding device 16 Brake for feeding stop 17 Rotating guider 18 Drive joint 19 Guide member 20 Winding device drive source 21 Drum 22 Brake base 23 Brake Base Slider 24 Fixed Strut 25 Spring 26 Rotating Strut 27 Slide Stop Brake 28 Translation Drive Unit 29 Slide Support Point (A)
30 Slide support point (B)
31 Junction point 32 Non-expandable link 33 Variable stiffness mechanism

Claims (6)

  In the method of moving the gripping member by the tension of the linear flexible link using the robot mechanism having the linear flexible link and the gripping member attached to the tip of the linear flexible link, the pulling operation of the linear flexible link and the winding of the linear flexible link A gripping member moving method comprising: moving a gripping member at a tip of a linear flexible link or an object grasped by the gripping member by performing an operation in cooperation.   In the method of moving the gripping member by the tension of the linear flexible link using the robot mechanism having the linear flexible link and the gripping member attached to the tip of the linear flexible link, the pulling operation of the linear flexible link and the winding of the linear flexible link A gripping member moving method comprising: moving a gripping member at a tip of a linear flexible link or an object grasped by the gripping member by repeating a coordinated operation of the motion.   In a gripping member moving device that moves a gripping member by the tension of the linear flexible link using a robot mechanism having a linear flexible link and a gripping member attached to the tip of the linear flexible link, a rigid arm is attached to a drive joint installed in the robot body. It is installed, and the rigid arm is provided with a linear flexible link feeding / winding means and a guiding means, and it is possible to control the rigid arm swinging and the linear flexible link winding in a coordinated manner. A gripping member moving device.   An elastic member such as a spring is attached between the brake pedestal slider that allows free sliding movement relative to the rigid arm and the fixed support fixed to the rigid arm, and the brake pedestal slider is relative to the rigid arm. The apparent rigidity of the linear flexible link is made variable stepwise by mounting a slide stopping means for stopping the movement and a feeding stop means for stopping the movement of the linear flexible link. The holding member moving device as described.   A brake pedestal slider that allows free sliding movement relative to the rigid arm and a translation drive that allows sliding movement relative to the rigid arm, and a post fixed to the translational drive, An elastic member such as a spring is mounted between the brake pedestal slider, and a slide stop means for stopping relative movement with the rigid arm and a feeding stop means for stopping the movement of the linear flexible link are mounted on the brake pedestal slider, 4. The gripping member moving device according to claim 3, wherein the apparent rigidity of the linear flexible link is continuously variable by controlling the displacement of the elastic member using the translation drive unit. A brake pedestal slider that can freely slide relative to the rigid arm is installed, and the brake pedestal slider has a slide stop means that stops relative movement with the rigid arm and a linear flexible link that stops the movement. A stop means is mounted, and support points that are driven so as to slide on the respective support columns with respect to the fixed support columns provided on the rigid arm and the rotary support columns having a rotary joint are provided, and an elastic member such as a spring is provided between the support points. By connecting the rotating strut and the brake pedestal slider with a link that does not expand and contract, and changing the relative position of the support points to control the displacement of the elastic member, the apparent flexibility of the linear flexible link by the lever principle 4. The gripping member moving device according to claim 3, wherein the rigidity is continuously variable.

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