JP2791030B2 - Curved copying controller for multi-degree-of-freedom work machine - Google Patents

Description

The present invention relates to a curved surface copying control device for a multi-degree-of-freedom working machine, and more particularly to a semi-automatic grinder for performing deburring, curved surface polishing, etc., for teaching a robot. The present invention relates to a curved scanning control device for a multi-degree-of-freedom work machine suitable for curved scanning operations such as scanning control and scanning control used for a three-dimensional measuring device.

[Conventional technology]

Conventionally, for operations that follow an uncertain shape such as deburring work or grinding a curved surface, the necessary positioning or attitude is determined using a multi-degree-of-freedom work machine such as a robot, and in this case, as shown in FIG. By attaching a tool such as a grinder 101 to the wrist 100 via a spring 102 or a damper 103, errors between the path of the robot and the path of the workpiece 104 have been absorbed.

In such a copying operation by a robot, the robot is generally moved by a teaching / playback method. In the teaching / playback method, a teacher sequentially counts necessary positions (points) with respect to the robot, and the robot follows a predetermined trajectory to reproduce the taught points one after another. The trajectory between the counted points has a function of interpolating with a straight line or an arc. The work can be performed by the robot moving along the locus determined in this way.

[Problems to be solved by the invention]

By the way, in the teaching / playback method, it is necessary to determine at least three-dimensional data on the position in order to teach a point. In some cases, it is necessary to add one to three-dimensional data on the posture. In the robot having the configuration shown in FIG. 16, the movable range of the portion of the spring 102 and the damper 103 is limited, and the teaching point must be within this range. Further, if the work shape becomes more complicated, it is necessary to close the teaching point between the points at most, and to make the working point fall within the movable range of the spring and the damper even in the movement locus between the points. Therefore, the teaching operation is very complicated, and it is easy to make a mistake at the time of the teaching, which takes a long time.

An object of the present invention is to provide a curved surface copying control device for a multi-degree-of-freedom working machine that is easy to operate, has a high working speed, and has little fatigue for workers.

[Means for solving the problem]

The above object is to provide a force setting means for setting a magnitude of a force applied to the work tool, a two-dimensional input means comprising a manual joystick for setting a moving direction of the work tool,
A base coordinate system fixed to the space where the multi-degree-of-freedom work machine is installed is defined as an orthogonal coordinate system that defines a space in which the work tool moves, and one of the three orthogonal axes is determined by force setting means. Control means for performing arithmetic control for instructing the magnitude of the set force and performing control arithmetic for instructing the moving direction set by the two-dimensional input means for the remaining two axes. Achieved by the device.

Further, the object is to provide a force setting means for setting a magnitude of a force applied to the work tool, a two-dimensional input means comprising a manual joystick for setting a moving direction of the work tool, and a movement of the work tool. As a rectangular coordinate system that defines a space, a work surface coordinate system that has an origin at the tip of a work tool that comes into contact with the work surface, and has a normal direction of the work surface as one of three axes is defined. A control for instructing the magnitude of the force set by the force setting means for one axis in the normal direction of the three axes, and for instructing the moving direction set by the two-dimensional input means for the remaining two axes This is achieved by a curved surface copying control device having control means for performing calculations.

At this time, the control means can calculate the normal direction of the work surface from the reaction force of the contact point between the work tool and the work surface detected by the force detection means to determine the work surface coordinate system.

Further, the control means, based on the moving direction of the work tool set by the two-dimensional input means and the reaction force detected by the force detection means, sets one axis of the work surface coordinate system predetermined for the work tool on the work surface. It is possible to calculate a target value at a position where the position coincides with the normal direction, and perform a control operation that also indicates the posture of the work tool based on the target value at this position.

The control means preferably performs arithmetic control by virtual compliance control.

The control means can input the moving direction of the work tool set by the two-dimensional input means in any form of a target value of position, a target value of speed, or a target value of force.

[Action]

The control means instructs the magnitude of the force set by the force setting means for one of the three orthogonal axes of the base coordinate system, and a manual joystick for the remaining two axes.
Since the control calculation for instructing the moving direction set by the dimension input means is performed, if the operator sets the force setting means to an arbitrary value, the operator only needs to manually operate the two-dimensional input means to use the work tool. It can be moved following the curved surface of the work surface.

Further, the control means instructs the magnitude of the force set by the force setting means for one of the three orthogonal axes of the workpiece surface coordinate system in the normal direction, and comprises a manual joystick for the remaining two axes. Since the control operation for instructing the moving direction set by the two-dimensional input means is performed, if the operator sets the force setting means to an arbitrary value, the operator only needs to manually operate the two-dimensional input means to obtain a work tool. Can be moved following the curved surface of the work surface. Further, the moving direction of the work tool can be defined on the tangent plane of the curved surface, and since the moving direction is along the curved surface, the distance and speed can be easily intuitively sensed, and the operability is further improved.

At this time, when a control operation for instructing also the posture of the work tool based on a target value of a position where one axis of a predetermined work surface coordinate system is made to coincide with the normal direction of the work surface is performed on the work tool, In addition, the working tool can always be pressed at a fixed angle against the work surface.

When the virtual compliance control is adopted by the control means, it is possible to easily switch and set the force control and the position control in each axial direction by appropriately changing the values of the virtual spring coefficient, the mass, and the viscosity coefficient. it can.

The control means inputs the moving direction of the work tool set by the two-dimensional input means in the form of a target value of position, a target value of speed, or a target value of force. The moving direction of the work tool is controlled by the position control, the speed control, and the force control, and an operation can be performed that makes use of the advantages of each control mode according to the work situation.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In FIG. 1, reference numeral 1 denotes a multi-degree-of-freedom work machine for performing a curved surface copying work on the surface of a work 2, and has a work tool 3 movable to an arbitrary position at the tip of a hand 1A. Generally, the multi-degree-of-freedom work machine 1 only needs to have two or more degrees of freedom, but in the present embodiment, a robot having three degrees of freedom is used for convenience of explanation.

The curved surface copying control device of the multi-degree-of-freedom work machine 1 generates one type of signal, generates a force setting device 4 for setting the magnitude of a force applied to the work tool 3, and generates two types of independent signals. A manual two-dimensional input device 5 for setting the moving direction of the work tool 3 and a force sensor connected between the hand 1A and the work tool 3 for detecting the magnitude of the force applied to the work tool 3 6, a goniometer 7 for detecting an axis angle around each joint of the multi-degree-of-freedom work machine 1, a force setting device 4, a two-dimensional input device 5, a force sensor 6, and information obtained from the goniometer 7. The controller 8 outputs a control signal to the multi-degree-of-freedom work machine 1.

The force setting device 4 may use an analog input device such as a potentiometer, but may use a digital input device such as a numeric keypad. The two-dimensional input device 5 can use a joystick or the like. Force sensor 6
Adopts a device that corresponds to three degrees of freedom of the work machine 1 and can measure forces in three orthogonal axes directions. As the goniometer 7, an encoder attached to a drive motor that drives around each joint can be used.

The controller 8 is, roughly speaking, the working tool 3.
A base coordinate system, which will be described later, is defined as an orthogonal coordinate system that defines a space in which the object moves, and arithmetic control is performed to indicate the magnitude of the force set by the force setting device 4 for one of the three orthogonal axes. Control means for performing a control device for instructing the movement direction set by the two-dimensional input device 5 with respect to the two axes. FIG. 2 shows a control block of this control means.
The control block shown in FIG. 2 is one of the methods for controlling the force and the position.
(1986), pp. 343-350, JP-A-60-3010 and JP-A-61-60
This is an example in which virtual compliance control described in No. 7905 is adopted, and a block of the virtual compliance control is indicated by reference numeral 10.

Virtual compliance control is a spring-mass formula [M]: virtual mass [C]: virtual viscosity coefficient [K]: virtual spring coefficient By entering And calculate this Is used to move the robot. At this time
Since M, C, and K are constants in calculation, the motion characteristics of the robot can be changed by changing these values. When applying equation (1) to a 3-DOF robot (1)
The expression may be three-dimensional. Expressing this in a rectangular coordinate system, Is a three-dimensional vector whose elements are the x, y, and z components of rectangular coordinates, respectively, and [M], [C], and [K] are 3 × 3 pairs each having a diagonal element. It may be an angular matrix. As a result, the operation characteristics can be changed in each of the three axes of x, y, and z. For example, if the component of [K] in the z-axis direction is set to zero, position feedback is cut off, and only force control is performed on the z-axis. Furthermore, [M],
By appropriately selecting the values of [C] and [K], the x-axis and y-axis become rigid and position control becomes possible.

By adopting virtual compliance control in this way,
Force and position control modes can be switched and selected for each axis.

The virtual compliance control 10 shown in FIG. 2 includes a dead zone calculation unit 11, a spring constant multiplication unit 12, a subtraction unit 13, and a characteristic compensation calculation unit 14 to realize the above-described control calculation.

The overall function of the control means shown in FIG. 2 including the virtual compliance control 10 will be described below together with its operation. First, the force detected by the force sensor 6 is represented in a sensor coordinate system having the detection center of the sensor as the coordinate origin. Is converted to a value in the hand coordinate system. Next, this is converted to the value of the base coordinate system by coordinate exchange 16 Get. In general, the base coordinate system refers to a coordinate system fixed in a space in which the robot, that is, the multi-degree-of-freedom work machine 1 is installed, and the direction of three orthogonal axes is the base coordinate system. The origin is the same as the hand coordinate system in the sense that it matches the system. This base coordinate system is the above-described orthogonal coordinate system that defines the space in which the work tool 3 moves. Value obtained by coordinate transformation 16 Is the target force value input from the force setting device 4. (Only the magnitude Fr in the z-axis direction and the values in the other axis directions are zero). Get.

On the other hand, axis angle data from a goniometer 7 such as an encoder for detecting the axis angle of each joint of the multi-degree-of-freedom work machine 1 Which is calculated by the position calculation 19 in the base coordinate system. Convert to

The two-dimensional input device 5 for setting the moving direction of the work tool 3 is a position increment proportional to the analog input. (ΔP (i) for x axis, ΔP (i) for y axis
y) is calculated at regular intervals, and this is calculated by the position target value calculation 20 at the current target position. To the new target position Get. That is, in the position target value calculation 20, the following calculation is performed.

The position target value calculation 20 may be performed not on the controller 8 side but on the two-dimensional input device 5 side.

Value calculated by position target value calculation 20 Is the target position value And outputs this value and the value from the position calculation 19 described above. Comparator 21 compares Get.

Force deviation at comparator 17 And position deviation at comparator 21 Is input to the virtual compliance control 10 described above, and performs a characteristic compensation operation on the control. In the present embodiment, force control is performed in the z-axis direction of the base coordinate system, and position control is performed in the x-axis and y-axis directions. Force control to achieve dead zone 11
The value of the force in the x- and y-axis directions Is cut off to realize position control in the x-axis direction and the y-axis direction. The final value calculated in this way Is the velocity expressed in the base coordinate system, this value Is the joint velocity of the multi-degree-of-freedom work machine 1 by the angular velocity calculation 22 Then, the motor speed calculation 23 taking into account the influence of the speed reducer and the like is performed, and this is output to the servo amplifier 24 to move the multi-degree-of-freedom work machine 1.

FIG. 3 shows a hardware configuration of the controller 8. CPU3
0 performs the processing of the control calculation shown by the control block in FIG. A program for performing this processing is input in the ROM 31 in advance, and the RAM 32 is used to store the results of the calculation and the like. Analog signals from the force setting device 4, the two-dimensional input device 5, the force sensor 6, and the goniometer 7 are digitized and processed by the A / D converter 33. When the keyboard 34 is used for the force setting device 4, the digital signal is directly input. The final processing result is converted into an analog signal through the D / A converter 35, and the multi-degree-of-freedom work machine 1 is moved through the servo amplifier 24.

An example of the curved surface copying operation performed by the control device configured as described above will be described with reference to FIG. In the figure, O-xyz is a base coordinate system. As a work content, at a certain time, the work tool 3 At this point, the work tool 3 will be Let's consider moving to the point 2 while maintaining contact with the work 2. First, the operator inputs the magnitude of the force Fr in the z-axis direction of the base coordinate system using the force setting device 4. This value is output to the comparator 17 And the force control for generating the force Fr in the z-axis direction of the base coordinate system is performed by the above-described function of the virtual compliance control 10. Thus, the work tool 3 is pressed in the z-axis direction so that the pressing force matches Fr. In such a state, the operator manually operates the two-dimensional input device 5 and pushes the lever thereof. Tilt in the direction of. The two-dimensional input device 5 assigns the moving direction to the x-axis and the y-axis of the base coordinate system, and two types of signals corresponding to the directions are input to the position target value calculation 20 described above. The position target value calculation 20 is based on the above-mentioned equation (2). Is calculated and input to the comparator 21, and the position control is performed by the above-described function of the virtual compliance control 10.
As a result, the work tool 3 is pressed against the work surface with the force Fr. Moved until you reach the point.

Therefore, as described above, if the operator sets the force setting device 4 to an arbitrary value, the operator manually operates the two-dimensional input device 5 to press the work tool 3 according to the curved surface of the work surface in a predetermined manner. It can be moved freely by force.

In the above embodiment, the moving direction of the working tool 3 set by the two-dimensional input device 5 is input as a target value of position (position increment). Can also be entered as FIG. 5 shows such an embodiment. In this control block, the position feedback is removed and the input signal from the two-dimensional input device 5 is left as it is. Is input in the form of a speed target value. With such a configuration, the target position represented by the above-described equation (2) greatly deviates from the current position due to the motion characteristics of the robot.
Even if the input from the two-dimensional input device is cut off, the problem that the robot is still moving is eliminated.

In addition, the moving direction of the work tool 3 set by the two-dimensional input device 5 can be input as a target force value. FIG. 6 shows such an embodiment. In this control block, the feedback of the position including K of the spring constant multiplying unit 12 is removed, and 2 is applied to the input of the x-axis and the y-axis on the force target value side. Information from the dimension input device 5 is input. As a result, for example, if there is an obstacle in the traveling direction of the robot and the robot collides with the obstacle, the position target value shown in FIG.
When the moving direction is instructed by the speed target value shown in the figure, the position or speed feedback gain is increased due to the difference between the target and the actual, and there is a problem that the robot is damaged or the work is broken. If the moving direction is input by force as in the present embodiment, there is no problem just by contacting the work tool 3 and the work 2 with the set pressing force,
It is advantageous.

Still another embodiment of the present invention will be described with reference to FIG. In the figure, the same members as those in FIG. 2 are denoted by the same reference numerals. In the above embodiment, the base coordinate system is defined as an orthogonal coordinate system that defines the space in which the work tool 3 moves, and the control calculation in the virtual compliance control 10 is performed in the base coordinate system. However, as a rectangular coordinate system, a work surface coordinate system having an origin at the tip of the work tool 3 in contact with the work surface and having the normal direction of the work surface as one of the three axes may be defined. FIG. 7 shows such an embodiment.

That is, in FIG. 7, the value of the force sensor 6 converted into the base coordinate system by the coordinate conversion 16 is converted into the value of the workpiece surface coordinate system by the coordinate exchange 40 by a method described later. Is converted to Are processed by the comparator 17 and then input to the virtual compliance control 10.

On the other hand, the moving direction of the two-dimensional input device 5 is assumed to be set in the work surface coordinate system, and the position increment is proportional to the analog input of the two-dimensional input device 5. (ΔP (i) for x axis, ΔP (i) for y axis
y) is converted to a base coordinate system by a coordinate conversion 41, and this is converted to a current target position by a position target value calculation 20. To the new target position To get the position target value Output as This value And the value obtained by position calculation 19 Are compared by the comparator 21 to calculate the position deviation in the base coordinate system. And convert this value to the value in the workpiece surface coordinate system by coordinate transformation 42. And inputs this value to the compliance control 10.

Furthermore, the value calculated by virtual compliance control 10 Is the velocity expressed in the work surface coordinate system, and is the value expressed in the base coordinate system by the coordinate conversion 43. And inputs this to the angular velocity calculation 22.

In the coordinate conversions 40 to 43, the work surface coordinate system may be calculated as data for a coordinate exchange matrix for performing a conversion from the base coordinate system to the work coordinate system or a conversion from the work coordinate system to the base coordinate system. is necessary. FIG. 8 shows a control block for performing this calculation. Work tools 3
Is in contact with the workpiece surface, a reaction force acts on the work tool 3 in the direction normal to the tangent plane as a reaction of the force,
This reaction force is detected by the force sensor 6. The detected reaction force is converted to a base coordinate system by a coordinate conversion 16. The reaction force converted into the base coordinate system is used for calculating the workpiece surface coordinate system. That is, the direction of the reaction force converted to the base coordinate system by the normal direction calculation 44 is set as the direction of the normal to the work surface. Next, in the work surface coordinate system coordinate axis calculation 45, the normal direction that matches the direction of the reaction force converted into the base coordinate system is determined as the direction of the zi axis in the work surface coordinate system. In addition, the work surface coordinate system coordinate axis calculation 45 includes the base coordinate system Ob-xb
The data of ybzb (see FIG. 9) is input in advance, is in the xb-zb plane of the base coordinate system, and takes the xi axis in the direction perpendicular to the zi axis obtained above. Further perpendicular to the Z axis and x axis,
The yi axis is determined so that the coordinate system is a right-handed system. Thus, a work surface coordinate system having an origin at the tip of the work tool 3 that comes into contact with the work surface can be defined. This work surface coordinate system data is sent to coordinate conversions 40 to 43, and each coordinate conversion
At 43, a transformation matrix between the work coordinate system and the base coordinate system is calculated, and each coordinate transformation is performed.

An example of the curved surface copying operation according to this embodiment is shown in FIGS.
This will be described with reference to FIG. In the figure, the base coordinate system is Ob-xb
Expressed as ybzb. As in the work contents, the work tool 3 is transferred to the work 2 at a certain time, as in the above-described embodiment. At the point of, the work tool 3 Let's consider moving to the point 2 while maintaining contact with the work 2. First, the operator inputs the magnitude of the force Fr in the z-axis direction of the work surface coordinate system using the force setting device 4. This value is output to the comparator 17 Is entered as On the other hand, since the work tool 3 is in contact with the work surface, the reaction force is detected by the force sensor 6, and the data of the work surface coordinate system calculated by the work surface coordinate system coordinate axis calculation 44 as described above is subjected to coordinate exchange. 40 to 43, the target force Fr of the force setting device 4 is compared by the comparator 17 with the force converted to the work surface coordinate system by the coordinate conversion 40, and the work surface coordinate is calculated by the above-described function of the virtual compliance control 10. Force control for generating a force Fr in the z-axis direction of the system is performed. As a result, the work 3 is pressed with the pressing force Fr in the direction normal to the surface of the work. In such a state, the operator manually operates the two-dimensional input device 5 and pushes the lever thereof. Tilt in the direction of. The two-dimensional input device 5 assigns the movement direction to the xi axis and the yi axis of the workpiece surface coordinate system, and two types of signals corresponding to the axes are input to the coordinate exchange 41 and the position target value calculation 20 described above. In the coordinate exchange 41, the target position of the two-dimensional input device 5 is converted into the base coordinate system, and the new target position calculated by the position target value calculation 20 is calculated. Is input to the comparator 21, and the position control is performed by the above-described function of the virtual compliance control 10. As a result, the work tool 3 is pressed by the force Fr in the normal direction of the work surface. Moved until you reach the point.

Thus, the operator can move the work tool 3 to an arbitrary position by operating the lever of the two-dimensional input device 5, and furthermore, the work surface coordinate system Is continuously updated based on the reaction force direction detected at that point in time, so even if the curved surface is complicated, it is possible to easily perform the curved surface copying operation without misunderstanding the moving direction. It can be carried out.

This embodiment is an example in which the moving direction of the work tool 3 set by the two-dimensional input device 5 is input as a target value (position increment) of the position, but similar to the embodiment shown in FIG. The moving direction of the working tool can be input as a target value of speed or a target value of force. In this case, as shown in FIGS. 11 and 12, corresponding to FIGS. can do. With this configuration, it is possible to obtain the same functions and effects as those of the embodiment shown in FIGS. 5 and 6.

Still another embodiment of the present invention will be described with reference to FIGS. In FIG. 13, the same members as those shown in FIG. 7 are denoted by the same reference numerals. In this embodiment, one axis of the work surface coordinate system predetermined for the work tool is determined based on the moving direction of the work tool set by the two-dimensional input device and the reaction force detected by the force sensor. A target value at a position to be matched with the normal direction is calculated, and the attitude of the working tool is also controlled based on the target value at this position. In this embodiment, a five-degree-of-freedom robot is used as the multi-degree-of-freedom work machine 1, and a force sensor 6 that can measure axial forces and moments in three axial directions is used.

In FIG. 13, the position increment proportional to the analog input of the two-dimensional input device 5 (ΔP (i) for x axis, ΔP (i) for y axis
y) takes a value expressed in the work surface coordinate system. This position increment Is converted to a value of the base coordinate system by a coordinate conversion 41, and the position target value Is calculated. On the other hand, a calculating unit 51 calculates a reaction force direction vector of a force whose magnitude is 1 from the force converted into the base coordinate system by the coordinate conversion 16, and adds the reaction force direction vector to the position target value xr by the adder 52. To obtain a position target value x′r including a posture control for orienting the zti axis of the tool coordinate system Oti-xtiytizti (see FIG. 14) defined in the work tool 3 described later in the direction of the reaction force vector. .

An example of the curved surface copying operation according to this embodiment is shown in FIGS.
This will be described with reference to FIG. In the figure, the base coordinate system is Ob-xb
Expressed as ybzb. The coordinate system fixed on the work tool and moving with the movement of the tool is represented by Oti-xtiytizti.
As in the work contents, the work tool 3 is transferred to the work 2 at a certain time, as in the above-described embodiment. At this point, the work tool 3 will be Let's consider moving to the point 2 while maintaining contact with the work 2. By the target force Fr set by the force setting device,
The work 3 is pressed by the pressing force Fr in the normal direction of the work surface in the same manner as in the embodiment shown in FIG. In such a state, the operator manually operates the two-dimensional input device 5 and pushes the lever thereof. Tilt in the direction of. The two-dimensional input device 5 assigns the moving direction to the xi axis and the yi axis of the workpiece surface coordinate system, and outputs two types of signals corresponding to the axes. This signal is coordinate exchange
41, position target value calculation 20 Is input to the comparator 21, and the position is controlled by the virtual compliance control 10. As a result, the work tool 3 is pressed by the force Fr in the normal direction of the work surface. Is moved until the point is reached, and the coordinate system Oti−x
The posture is controlled so that the zti axis of tiytizti matches the direction of the detected force. Here, zt in the axial direction of the work tool 3
When the i axis is taken, the contact point position O between the work tool 3 and the work 2
The posture is controlled so that i does not change and the axial direction of the work tool matches the direction of the detected force. That is, in FIGS. 14 and 15, The tool 3 whose posture is in the direction of zti-1 at the point of At the point of, turn the posture to zti so that it matches the direction of the detected force, At point, the posture is oriented in the direction of zti + 1.

The dotted line at the point indicates the direction of zti-1.

By controlling the posture of the work tool by the reaction force of the force as described above, the work tool can be pressed and moved while maintaining a certain angle with respect to the work surface, so that the curved surface copying operation can be performed more easily. be able to.

〔The invention's effect〕

 According to the present invention, the following effects can be obtained.

1. Since copying can be performed with the same feeling as moving in a plane regardless of the shape of the curved surface of the work, operation is easy and fatigue is reduced.

2. When applied to teaching, simplification of operation increases teaching speed. At this time, if the attitude of the work tool is also controlled, teaching of the attitude is not required, and teaching can be performed more quickly.

3. In the case of grinders, etc., there is no need to hold working tools in hand, so there is little fatigue.

4. When the work surface coordinate system is defined as the orthogonal coordinate system, the moving direction is along the curved surface, so that the distance and speed can be easily perceived intuitively, and the operability is further improved.

5. If the posture of the work tool is also controlled, the work tool can always be pressed at a fixed angle against the work surface when grindering, etc.
Processing accuracy is improved.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an entire curved surface copying control device for a multi-degree-of-freedom work machine according to an embodiment of the present invention. FIG. 2 is a control block diagram showing the control contents of the control device. The figure is a schematic diagram showing the hardware configuration of the control device,
FIG. 4 is a diagram for explaining a curved surface copying operation by the control device. FIG. 5 is a control block diagram showing control contents of a curved surface copying control device according to another embodiment of the present invention.
FIG. 6 is a control block diagram showing control contents of a curved surface copying control device according to still another embodiment of the present invention, and FIG. 7 is a control content of a curved surface copying control device according to still another embodiment of the present invention. FIG. 8 is a control block diagram showing control contents for calculating a work surface coordinate system of the control device, and FIG. 9 is a description for explaining a curved surface copying operation by the control device. 10 (A) and (B) are X (A) -X in FIG. 9 respectively.
FIG. 11 is a cross-sectional view taken along the line (A) and the line X (B) -X (B), and FIG. 11 is a control block diagram showing control contents of a curved surface copying control device according to still another embodiment of the present invention. , Twelfth
FIG. 13 is a control block diagram showing control contents of a curved surface copying control device according to still another embodiment of the present invention. FIG. 13 is a control diagram showing control contents of a curved surface copying control device according to still another embodiment of the present invention. FIG. 14 is a block diagram, and FIG. 14 is an explanatory diagram for explaining a curved surface copying operation by the control device. FIGS. 15 (A) and (B) are XV in FIG.
FIG. 16 is a sectional view taken along lines (A) -XV (A) and XV (B) -XV (B), and FIG. 16 is a schematic view showing a conventional curved surface copying control device. DESCRIPTION OF SYMBOLS 1 ... Multi-degree-of-freedom work machine, 2 ... Work 3 ... Work tool, 4 ... Force setting device 5 ... 2D input device, 6 ... Force sensor 7 ... Angle meter 10 ... Virtual compliance control 40-43 ... Coordinate Conversion, 44: Normal direction calculation 45: Work surface coordinate system coordinate axis calculation 51: Force reaction force vector calculation

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI G05B 19/4097 G05D 3/00 N 19/427 G05B 19/42 G G05D 3/00 19/403 C (72) Inventor Kazunori Yamada 650, Kandachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. Tsuchiura Plant (56) References JP-A-63-203218 (JP, A) JP-A-1-1978111 (JP, A) JP-A-63-196367 ( JP, A) JP-A-63-47042 (JP, A) JP-A-50-61793 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G05D 3/00-3/12 G05B 19/42 B23Q 35/00

Claims (8)

(57) [Claims] 1. A curved surface copying control device for a multi-degree-of-freedom work machine, wherein a work tool is brought into contact with a work surface and can be moved to an arbitrary position, a force setting means for setting a magnitude of a force applied to the work tool, Two-dimensional input means consisting of a manual joystick for setting the moving direction of the work tool, and a rectangular coordinate system defining the space in which the work tool moves are fixed to the space where the multi-degree-of-freedom work machine is installed. A base coordinate system is defined, arithmetic control is performed for one of the three orthogonal axes to indicate the magnitude of the force set by the force setting means, and the remaining two axes are set by the two-dimensional input means. And control means for performing a control operation for instructing the moving direction. 2. A curved surface copying control device for a multi-degree-of-freedom work machine, wherein the work tool is brought into contact with a work surface and can be moved to an arbitrary position, wherein force setting means for setting a magnitude of a force applied to the work tool; Two-dimensional input means consisting of a manual joystick that sets the direction of movement of the work tool, and an origin at the tip of the work tool that contacts the work surface as a rectangular coordinate system that defines the space in which the work tool moves. Then, a work surface coordinate system in which the normal direction of the work surface is one of the three axes is determined, and the force set by the force setting means is determined for one of the three orthogonal axes in the normal direction. Control means for performing arithmetic control for specifying the size and performing control calculation for specifying the moving direction set by the two-dimensional input means for the remaining two axes. 3. The work surface coordinate system is determined by calculating the normal direction of the work surface from the reaction force of the contact point between the work tool and the work surface detected by the force detection device. 3. The curved surface copying control device according to claim 2, wherein: 4. The curved surface copying control apparatus according to claim 1, wherein said control means performs control calculation by virtual compliance control. 5. The curved surface copying control apparatus according to claim 1, wherein the control means inputs the moving direction of the work tool set by the two-dimensional input means as a target value of the position. 6. The curved surface copying control apparatus according to claim 1, wherein the control means inputs the moving direction of the work tool set by the two-dimensional input means as a target value of speed. 7. The curved surface copying control device according to claim 1, wherein the control means inputs the moving direction of the work tool set by the two-dimensional input means as a target value of force. 8. The work surface coordinate system predetermined for the work tool based on the moving direction of the work tool set by the two-dimensional input means and the reaction force detected by the force detection means. A control value for calculating a target value at a position where one of the axes coincides with the normal direction of the work surface, and performing a control calculation for instructing also a posture of the work tool based on the target value at the position. The curved surface copying control device as described in the above.