JPH07205022A - Correcting method for grinding wheel wear in force control robot - Google Patents

Abstract

PURPOSE:To automatically, quickly and simply obtain the amount of grinding wheel wear, correct TCP and to prevent generation of unground parts due to wear by utilizing a movement based on a force control mode for a grinding operation of a force control robot. CONSTITUTION:A method for correcting grinding wheel wear is applied to a force control robot for grinding a workpiece 6 by means of a grinding wheel 7a based on the control of a position and a force by a control means 15 in accordance with a grinding route relating to the workpiece 6 by using a force signal from a force detecting means 5 and a position signal from a position detecting means 8. The tip of the grinding wheel is brought into contact with a reference surface before wear is generated, the position of TCP set to indicate the position and posture of the grinding wheel is obtained, likewise the position of a work center point is obtained after wear is generated, a difference therebetween is obtained as the amount of wear and based on this amount of wear a set value relating to the reference position of the work center point before wearing takes place.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for correcting grindstone wear of a force control robot, and more particularly, when the grindstone is worn during a grinding operation, the grindstone is moved in the force control mode in the direction of the grindstone part which has disappeared due to the wear. The present invention relates to a grindstone wear correction method for a grinding robot, which measures the wear amount and corrects the wear of the grindstone based on the wear amount obtained by the measurement.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. 61-15 has been used to grind an object to be ground using a robot mechanism.
There is a grinding robot disclosed in Japanese Patent No. 9366. In this grinding robot, a grindstone that is rotationally driven is attached to a hand portion of the robot, and various grinding processes are performed on an object to be ground using the grindstone.

For example, when a grinder is attached as a tool to the hand of a grinding robot having 6 degrees of freedom, the position of a certain point of the grindstone mounted on the grinder becomes an ideal contact point between the grindstone and the work, and this certain point Is set as the center point of the tool. The position of this point is generally TCP (Tool
Center Point) is called. When the tool is determined, the TCP is preset as a reference position (point) for controlling the position and orientation of the tool during the grinding operation when the tool is determined, and is stored in the memory of the control device. However, as the actual grinding operation progresses, the grindstone gradually wears, which causes a deviation between the initially set TCP and the actual contact point, and as a result, the planned grinding point and the actual grinding point. A gap may occur between the parts, and the part to be ground may be left uncut. Therefore, assuming that wear will occur in the grinding wheel during grinding work, when the deviation between the planned grinding location and the actual grinding location caused by the wear of this grinding wheel becomes a problem, some information about this deviation It is necessary to correct the content of the position control of the tool prepared in the memory of the control device so that the planned grinding position can be ground correctly by the detection.

As a conventional method for correcting wheel wear,
There are a method in which the operator moves the grindstone as necessary by observing the finish condition, and a method in which the grindstone is automatically moved by a fixed amount every fixed number of operations. In recent years, a method using a force sensor (for example, JP-A-1-177957) and a method for attaching a tool holding device to a wrist of a robot capable of sliding a tool according to wear of a grindstone (for example, JP-A-62-
9862), a method of detecting the wear amount of a grindstone by a sensor and operating a robot in accordance with a coordinate system set on the grindstone to correct the wear amount (for example, Japanese Patent Laid-Open No. 1-1717).
No. 61), a sensor detects a tip position of a grindstone corresponding to a plurality of grindstone postures, and based on that, a grinding operation locus is corrected in each posture (for example, JP-A-62-228860 and JP-A-63-295170). ) Is used.

[0005]

The method of correcting the finish condition by the operator requires manpower, and the determination of the finish condition may vary depending on the personal ability of the worker. In the method of automatically moving the grindstone by a fixed amount, the amount of wear of the grindstone differs depending on the object to be ground, so there is a difference between the actual amount of wear and the correction amount, resulting in uncut parts or overcutting. Is damaged. The method using the force sensor is effective only for correcting the wear in the pressing direction of the grindstone, but it is difficult to correct the grinding path depending on the wear condition of the grindstone. The method of mounting the slide device not only makes the wrist larger, but also cannot withstand high loads and shocks, and the device for performing accurate positioning becomes expensive, which causes reliability problems in adverse environments. .

The method of correcting the wear amount of the grindstone detected by a sensor or the like by operating the robot in accordance with the coordinate system set on the grindstone is difficult to deal with a plurality of grinding postures of the robot. Further, in the method of detecting the grindstone tip position in a plurality of grinding postures using a sensor and correcting the grinding path of the robot accordingly, it takes time to detect the grindstone tip positions corresponding to the plural grinding postures, It is difficult to handle grinding work that changes the grinding posture frequently.

The object of the present invention is to find the position of the cutting edge of a grindstone before and after wear by utilizing each movement of the force control mode and the contact in the grinding operation by the force control robot, and automatically and quickly and easily. The amount of wear is calculated, and the preset amount of wear is used as a reference for grinding path information.
The object of the present invention is to provide a grindstone wear correction method for a force control robot that appropriately corrects the position data of (1) and prevents the occurrence of uncut residue caused by wear.

[0008]

According to a grinding wheel wear correction method of the present invention, a force signal outputted from a force detecting means for detecting a force applied to a grindstone and a position outputted from a position detecting means for detecting a position of the grindstone. A control means for controlling the position and the force with respect to the movement of the grindstone by using the signal is provided, and the grinding object is the grindstone based on the position and the force control by the control means according to the grinding path previously taught with respect to the grinding object. A grindstone wear correction method applied to a force control robot for grinding, in which a blade tip of the grindstone is brought into contact with an arbitrary reference surface before occurrence of wear, and a work center point set to represent the position and orientation of the grindstone (that is, TCP) position, and then, after wear occurs, the blade tip of the grindstone in the grinding work posture is moved in the movement direction in the force control mode and brought into contact with the reference surface, and the position of the work center point is obtained again and wear is performed. of The difference between the positions of the subsequent work center points is obtained as the wear amount, and the set value relating to the reference position of the work center point before the wear based on the wear amount (value given in the coordinate system set on the wrist of the robot) It is characterized by changing. The position of the work center point calculated for the calculation of the wear amount is represented by the robot coordinate system or the absolute coordinate system.

In the above method, when the edge of the grindstone after abrasion is brought into contact with the reference surface, a force is applied in a direction opposite to the direction in which the edge of the grindstone wears (the direction of the originally existing grindstone before abrasion). The movement is set in the control mode, the moving direction is represented by a vector, and the wear amount in the direction represented by the vector is obtained.

In the above method, preferably, when the edge of the grindstone after abrasion is brought into contact with the reference surface, the blade edge of the grindstone before abrasion is brought into contact with the same pressing force as the contact force.

[0011]

According to the present invention, in the grinding operation, the cutting edge of the grindstone before and after abrasion is brought into contact with the reference surface, data relating to the position of the cutting edge is obtained for each, and the position of the point set in advance for expressing the position and the posture of the grindstone. The amount of wear of the grindstone is obtained from the difference (positional deviation), and the set value relating to the position of the work center point is changed based on the value, and the wear of the grindstone is corrected accordingly. The grindstone is moved in the force control mode and brought into contact with the reference surface to obtain position data, and the wear amount is obtained using these position data. Therefore, the wear amount can be accurately and easily obtained, and the work center point Corrections can be made. At this time, when the blade edge of the grindstone after abrasion is brought into contact with the reference surface, the force control mode is set with respect to the movement direction for contact to perform movement, and preferably the same as the force with which the grindstone edge before abrasion is brought into contact. Since the contact is made by the pressing force, the error due to the influence of the bending or the like can be extremely reduced. In addition, since the coordinate system is set in the direction in which the grindstone wears, force control is performed, and movement is performed to obtain the wear amount in that direction, only one contact operation is required, which is quick, reliable, and accurate. It is possible to correct grindstone wear.

[0012]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows the system configuration of a force control robot for carrying out the grinding wheel wear correction method according to the present invention. In particular, the configuration of a control unit for controlling the operation of the robot body is shown in a block diagram.

In FIG. 1, reference numeral 1 is a robot body having a plurality of joints, which is equipped with an arm 2 and is mounted on a base 3. Based on the movable action of each joint of the robot body 1, the tip of the arm 2 moves to a position required for work, and the overall posture of the robot body 1 including the arm 2 changes to a posture required for work. A six-axis force sensor 5 is attached to a wrist portion 4 located at the tip of the arm 2, and a grinding tool 7 for performing required work on a work 6 which is a work object is attached to the force sensor 5 at the tip thereof. To be The robot body 1 has a plurality of built-in motors for operating the joints. An angle meter 8 for measuring the driving amount is attached to each of these motors, and the angle meter 8 obtains axial angle data of each joint.

Next, the structure of the control device for controlling the operation of the robot body 1 will be described.

FIG. 1 is a block diagram showing the configuration of the control device. The control device is configured by software technology using a computer, for example. In the operation of the robot body 1, this control device controls the position and force for performing a required work.

In FIG. 1, reference numeral 9 denotes a force target value setting unit, 10
Is a position target value setting unit. In the force target value setting unit 9, x,
Target value of pressing force <fr> for each coordinate axis of y and z
Is preset, and the force target value setting unit 9 outputs the set target value <fr> to the subtractor 11. The force target value is set by teaching the data. Here, the symbol “<fr>” means that fr is a vector quantity. The notation "<>" is used in the same meaning below.

The position target value setting unit 10 sets a target value <pr> for the position of the grinding tool 7 for each of the x, y, and z coordinate axes.
Is set in advance, and the position target value setting unit 10 outputs the set target value to the subtractor 12. For setting the position target value, for example, a value obtained by interpolating teaching data is used.

The force detected by the force sensor 5 is the force calculation unit 1
3, the force calculation unit 13 converts the sensor coordinate system to the reference coordinate system which is the hand coordinate system, and also performs gravity compensation by subtracting the gravity amount of the grinding tool 7. Thus, the force <f> applied to the grinding tool 7 is calculated at the contact point between the work 6 and the grinding tool 7. The force data obtained by the force calculator 13 is given to the subtractor 11. On the other hand, the angle data of each axis obtained by the goniometer 8 is sent to the position calculator 14, where the grinding tool 7 in the absolute coordinate system is based on the angle data.
The position <p> of is calculated. The position data obtained by the position calculator 14 is given to the subtractor 12.

In the subtractor 11, the force <f> and the force target value <f
r> and the deviation <Δf> = <f>-<f
r> is output. On the other hand, in the subtractor 12, the position <p>
Is compared with the position target value <pr>, and the deviation <Δp> is output. Each deviation <Δf> and <Δ obtained in this way
p> is input to the position / force control calculation unit 15.

The position / force control calculation unit 15 selects one or both of the position control mode and the force control mode by setting parameters, and a control command value for executing the selected control mode. It has a function to calculate In the position control mode, the target speed vi which is proportional to the element Δpi of <Δp> is calculated. In the force control mode, the target speed vi is calculated in proportion to the element Δfi of <Δf>. The above calculation is performed for each coordinate axis. It is also possible to use Δpi and Δfi to configure the control in the compliance control mode.

The speed command value representing the target speed <v> obtained by the above calculation is output from the position / force control calculation unit 15 and supplied to the drive command unit 20. In the drive command unit 20,
The speed command value <v> is converted into a drive command value <θ> of each drive motor of the robot body 1. The converted drive command value is supplied to each drive motor of the robot body 1, and the motor operates at the required speed according to this command value.

The operation command section 21 is a circuit element for designating and setting the control mode of the control device for executing the position and force control. The operation command unit 21 has a function of storing operation data taught by an operator in advance, operating the control device based on the operation data, and causing the robot body 1 to reproduce the teaching operation. In the present embodiment, in particular, the control mode switching command 22 is given to the position / force control calculation unit 15, or the taught position data is interpolated to obtain the interpolation data 2.
4 is provided to the position target value setting unit 10 or the taught force target value 24 is output and provided to the force target value setting unit 9.

The operation command section 21 further commands the contact operation instruction section 25 to issue a contact operation instruction 26.
Or a contact determination signal 28 from the contact determination unit 27 and a position storage command 30 to the position storage unit 29.

The contact operation instruction section 25 prepares the coordinate data 37 of the grindstone set in the coordinate system setting section 36 based on the instruction 26 from the operation instruction section 21 in preparation for the contact operation of the grinding tool 7 of the robot body 1. A command 22A for setting the moving direction of the grinding tool 7 (direction in which contact with the reference surface on the work 6 is started) to the force control mode is output to the receiving / position / force control calculation unit 15. The contact operation instructing unit 25 also outputs a value suitable for the movement for contact as the force target value 23 to the force target value setting unit 9. In the coordinate system setting unit 36, coordinate data represented by the wrist coordinate system of the robot is set so that the direction in which the grindstone wears matches the arbitrary coordinate axis, and this data is used as the wear amount computing unit 32 described later. Send coordinate data to.

As described above, the contact operation instructing section 25 follows the command of the operation instructing section 21 and controls the moving direction of the grinding tool 7 via the force target value setting section 9 and the position / force control calculating section 15 and the like. To the force control mode, and the grinding tool 7
Has a function of instructing to move in the force control mode to contact the reference surface of the work 6. Contact force determination unit 27
Receives the output signal of the force calculation unit 13 and monitors the force output by the force calculation unit 13. When a predetermined contact force when the grinding tool 7 contacts the reference surface of the work 6 is detected, a contact determination signal 28 is sent to the operation command unit 21. At this time, the predetermined contact force is a reaction force when the blade edge of the grinding tool before wear contacts.

The position storage unit 29 is composed of a storage unit 29A and a storage unit 29B. The storage unit 29A stores the TCP (position and posture of the grinding tool when the grinding tool before wear comes into contact with the reference surface of the workpiece 6 in advance). The position of a preset point) is stored in order to represent it. Further, the storage unit 29B has the operation command unit 21.
It receives the position storage command 30 given from the position calculation unit 14 and stores the position data <p> output from the position calculation unit 14 at that time.

The wear amount calculation unit 32 is provided with the position information 31, 31 stored in the respective storage units 29A, 29B of the position storage unit 29.
Based on A and the coordinate data 38 set in the coordinate setting unit 36, the wear amount of the grindstone is obtained by the calculation described later, and TC
The wear amount data 33 is output to the P correction unit 34. T
The CP correction unit 34 changes the currently set TCP position setting value based on the wear amount data 33, and updates the new TCP position as the setting value.

Next, the operation of the grinding wheel wear correction method will be described with reference to FIGS.

FIG. 2 shows a grindstone 7a mounted on the grinding tool 7.
Before any wear occurs, for example, any reference surface 50 on the workpiece 6
Shows the state where the blade edge of the grindstone 7a is in contact with. Here the cutting edge of the grinding wheel 7a is represented by 51 (the coordinate system set in the wrist) of the hand coordinate system of the robot the _{TCP (x T, y T,} z
_T ) and the coordinate system (X _G , Y _G , Z _G ) 52 of the grindstone are set. The coordinate axis X _G is a vector, and the grindstone 7
It is set parallel to and opposite to the direction of wear of a. In the posture of the grindstone 7a and its moving direction shown in FIG. 2, the direction 53 in the figure is the direction in which the grindstone 7a is worn. The grindstone 7a in the state of the grinding work posture shown in FIG.
Is in contact with the reference surface 50 of the work 6 with a contact force f ₀ , and at this time, the position of TCP expressed by the base coordinate system 54 of the robot is P ₀ (x ₀ , y ₀ , z ₀ ). Remembered. The angle formed by the reference surface 50 and the grindstone 7a is α. After that, the grinding work is performed on the work by using the preset TCP before starting the work as described above and by using the data of the taught grinding path and the data related to the other conditions. Grinding stone 7 as grinding work progresses
The cutting edge of a is gradually worn.

FIG. 3 shows an example of a flow chart for correcting the wear of the grindstone after wear, and FIG. 4 shows the contact state between the grindstone after wear and the work reference surface. The timing for correcting the wear of the grindstone after wear is arbitrarily determined.

When the operation command section 21 gives the contact operation command 26 to the contact operation instructing section 25, the contact operation instructing section 25 outputs the command 22A to the position / force control calculating section 15 and the grindstone 7a.
The control mode in the approaching direction (X _G direction) to the workpiece 6 is set as the force control mode, and the control modes in other directions are set as the position control mode (step 40). Regarding the approaching direction, the contact operation instructing unit 25 performs force control in a state where the force target value set in the force target value setting unit 9 is fr.

In the next step 41, the movement operation in the force control mode is performed in the approach direction with respect to the movement of the grindstone 7a based on the above-mentioned set state. The grindstone 7a is kept in the posture of the grinding work. The angle formed by the reference surface 50 and the grindstone 7a is α. Since force control is performed for the movement in the approaching direction, in the control device, the deviation between the force target value fr set in the force target value setting unit 9 and the force f calculated in the force calculation unit 13 is subtracted. Required in 11. Since the description here applies only to the approaching direction, the force target value and the force are treated as scalar quantities. However, since the force received by the grindstone 7a is 0 in the air in the non-contact state, the value of Δf = −fr is input to the position / force control calculation unit 15. In the force control mode, the position / control calculation unit 15 outputs the speed v proportional to Δf.
Assuming that the gain of the position / force control calculation unit 15 at this time is Kc, v = −Kc · fr is input to the drive command unit 20,
The robot body 1 moves at the speed command value v described above. In other words, the robot body 1 operates at a speed proportional to the force target value fr set in the force target value setting unit 9. In the following description, this movement operation is referred to as “movement in force control mode”. Further, with respect to directions other than the approaching direction, the position control mode is set, and the target position value thereof is held at a constant value, so that it does not move in a direction other than the approaching direction. Therefore, the grindstone 7a moves linearly in the approaching direction. Here, as shown in FIG.
Movement direction is the direction of the vector X _G, the axis of the vector X _G passing through the point P _0.

In the above-mentioned moving state, the contact force judging section 2
7 inputs the force calculated by the force calculation unit 13 at an appropriate timing, and determines whether the force obtained in the approaching direction is larger than the force f ₀ set in the contact determination unit 27 (step 42). In the movement in the air, the contact force on the grindstone 7a, that is, the force applied as the external force is 0, so steps 41 and 42 are repeated during that time. The force f ₀ set in the contact determination unit 27 is the same force as when the grindstone before wear is brought into contact, and is a value smaller than the force target value fr for moving in the force control mode. By making the force set in the contact determination unit 27 the same as the contact force when determining the blade edge position of the grindstone 7a before wear, eliminating the position error element due to the deflection of the grindstone that occurs at the time of contact You can

When the tip of the grindstone 7a contacts the work 6,
The force sensor 5 detects the contact force, and the force calculator 15 outputs a signal corresponding to the force detected by the force sensor. For this reason,
The force f is input to the subtractor 11, and Δf becomes f-fr. At this time, the force control is performed so that Δf becomes zero.
The movement in step 43 becomes a normal force control state, and f =
It becomes fr and the speed v becomes 0 and the grindstone 7a stops.

In step 43, the force in the approaching direction is equal to or greater than the set value f ₀ . In this step 43, the position storage unit 2 is operated based on the position storage command 30 from the operation command unit 21.
9 is the TCP position P ₁ (x ₁ , y expressed in the base coordinate system at that time output from the position calculation unit 14).
₁ , z ₁ ) is memorized. In FIG. 4, reference numeral 55 denotes a blade tip portion of the grindstone 7a that has worn and disappeared.

At step 44, the stored P ₀ and P _{1 are} stored.
The amount of wear of the grindstone 7a is calculated based on each position information and the vector X _G. At this time, the wear amount Δe of the grindstone 7a is
For example, it is given by the following equation.

[0038]

[Equation 1]

If the direction cosine when the vector X _G is expressed in the hand coordinate system is (X _Gx , X _Gy , X _Gz ), the component in each direction expressed in the hand coordinate system in the direction in which the grindstone wears is , Is expressed by the following equation.

[0040]

[Expression 2] x-direction component Δe _x = Δe · X _Gx y-direction component Δe _y = Δe · X _Gy z-direction component Δe _z = Δe · X _Gz

In step 45, the TCP value initially set based on the amount of wear obtained in step 44 is set as shown in FIG.
To change the value relating to the position P ₂ of the new TCP shown in, it calculates a set value of the position P ₂ of the new TCP. The setting value of the new TCP position is calculated by the following equation.

[0042]

[Number 2] x-direction setting value _{x T '= x T -Δe x} y direction setpoint _{y T' = y T -Δe y} z direction setpoint _{z T} '= z _T -Δe z

In step 46, the current TCP setting value is updated with the new TCP position setting value obtained in step 45.

With this, in the subsequent grinding operation, the edge of the worn wheel can follow the desired grinding path without changing the position of the teaching point representing the grinding path taught for the grinding operation.

In the above-mentioned embodiment, the disk-shaped grindstone 7a is used as the grinding tool. As another embodiment, FIG. 5 shows a grinding tool 7 using a cup-shaped grindstone 7b. Also in the case of this grinding tool, it can be handled in the same manner as in the above-mentioned embodiment. in this case,
Set the coordinate system of the grindstone in the direction opposite to the direction in which the grindstone wears.
Match the _G axes. 56 is a direction in which the grindstone 7b is worn.

The work for contacting the cutting edge of the grindstone and its reference surface may be an actual work to be machined or a standard work prepared separately from the actual work. Good.

[0047]

As is apparent from the above description, according to the present invention, in a force control robot that is taught a grinding path for an object to be ground in advance before work, and a grindstone is used as a grinding path in a force control robot that performs grinding work according to this grinding path. Work center point (TC
P) was updated before the grinding operation was started to find the position of the cutting edge of the grindstone before and after the occurrence of wear, and the difference, that is, the wear amount, was updated to match the grindstone after wear. You can eliminate the uncut residue. Before the start of the grinding operation or during the grinding operation, the grinding operation is stopped at any time and the blade edge of the grindstone is brought into contact with the reference surface once so that the amount of wear of the grindstone can be corrected. It can be performed.

The edge position of the grindstone (T
CP) is obtained by moving and contacting the blade edge of the grindstone with respect to the reference surface in, for example, a force control mode (not limited to this), and the blade edge position of the grindstone after wear is similarly determined.
Since the blade tip of the grindstone is moved in the force control mode and brought into contact with the reference surface while maintaining the posture of the grinding operation, the force control mode can be used to detect an accurate position. In other words, with respect to the whetstone after wear, the direction in which the whetstone wears (the direction of the originally existing whetstone portion)
Since the position of the cutting edge is detected by performing the moving / contacting operation and the amount of wear is obtained by comparing this position data with the position data at the same point before wear, reliable and accurate wear correction can be performed.

When detecting the position of the TCP with respect to the grindstone after wear, since the contact is made with the same pressing force as in the case of detecting the position of the TCP before wear as a comparison reference, the influence of the deflection of the grindstone is eliminated. can do.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a force control robot to which a grindstone wear method according to the present invention is applied.

FIG. 2 is a diagram for explaining a state in which a position of a cutting edge is obtained with respect to a grindstone before wear.

FIG. 3 is a flow chart for explaining the process of correcting the wear of the grindstone.

FIG. 4 is a diagram for explaining a state in which a position of a cutting edge is obtained with respect to a grindstone after wear.

FIG. 5 is a diagram for explaining wear correction of a grindstone having another shape.

[Explanation of symbols]

 1 Robot Main Body 2 Arm 5 Force Sensor 6 Work 7 Grinding Tool 7a, 7b Grinding Stone 15 Position / Force Control Calculation Unit 32 Wear Amount Calculation Unit 34 TCP Correction Unit 50 Reference Surface 51 Robot Hand Coordinate System 52 Grindstone Coordinate System 54 Robot Robot Base coordinate system

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication location G05D 3/12 305 L 7740-3H (72) Inventor Kazunori Yamada 650 Kazutachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction machinery company Tsuchiura factory

Claims (3)

[Claims] 1. A position and a force relating to the operation of the grindstone by using a force signal output from a force detecting means for detecting a force applied to the grindstone and a position signal output from a position detecting means for detecting the position of the grindstone. A grindstone applied to a force control robot that grinds the grinding object with the grindstone based on position and force control by the control means according to a grinding path taught in advance for the grinding object. In the wear correction method, the edge of the grindstone is brought into contact with the reference surface before the wear occurs, the position of the work center point set to represent the position and the attitude of the grindstone is obtained, and the grind work is performed on the reference surface after the wear occurs. The position of the work center point before wear and the position of the work center point after wear are determined by moving the blade edge of the grindstone in the attitude in the moving direction in the force control mode and bringing them into contact with each other. The determined as a wear amount, wheel wear compensation method of force control robot and changes the set value for the reference position of the work center point of the front wear on the basis of said difference. 2. The grindstone wear correction method for a force control robot according to claim 1, wherein when the blade tip of the grindstone after abrasion is brought into contact with the reference surface, a direction opposite to a direction in which the blade tip of the grindstone is worn A grinding wheel wear correction method for a force control robot, characterized in that it is set to move in a force control mode, the moving direction is represented by a vector, and the amount of wear in the direction represented by the vector is obtained. 3. The grindstone wear correction method for a force control robot according to claim 1, wherein when the blade tip of the grindstone after abrasion is brought into contact with the reference surface, the blade tip of the grindstone before abrasion is brought into contact with the reference surface. A grinding wheel wear correction method for a force control robot, wherein the pressing force is the same as the pressing force.