JP6898808B2 - Single-axis robot with swivel arm and screw tightening robot with swivel arm - Google Patents

Description

The present invention relates to a single-axis robot with a swivel arm that is widely used for fastening fasteners such as screws, bolts, and nuts, mounting assembly parts, and bonding various joining materials, and particularly for fastening parts such as screws, bolts, and nuts. It relates to a screw tightening robot with a swivel arm used for fastening.

Conventionally, when fastening fasteners, mounting assembly parts, and bonding joining members, the installation space is small and the work area does not interfere with adjacent robots. Therefore, a single unit with a swivel arm provided with a predetermined work unit. Axis robots are often used. In this single-axis robot with a swivel arm, the working position is the Yyn value on the Y-axis coordinates (explaining the case where the single-axis robot is used as a Y-axis robot) by direct teaching and the rotation of the motor that swivels the swivel arm. The angle θn is selected and these are stored. In this type of single-axis robot with a swivel arm, as in the automatic screw tightening device described in Patent Document 1, the teaching work of the work point can be performed accurately, and the XY plane which is the processing data of the work object. Since the above coordinate data (Xn, Yn) can be used, mounting of a CCD camera is being considered.

Japanese Unexamined Patent Publication No. 5-237729

In this single-axis robot with a swivel arm, when the CCD camera is mounted, the CCD camera needs to be attached to the swivel arm, so that the CCD camera also swivels in the same manner as the swivel arm. As a result, the image captured by the CCD camera that captures the work point is tilted with respect to the Y-axis coordinates of the single-axis robot. Therefore, even if the displacement amount from the center of the CCD camera is calculated, this displacement amount is used as the work point of the work unit. Cannot be reflected in. Therefore, it is necessary to correct the inclination of the captured image and reflect it in the work point of the work unit, but the present situation is that there is no correction method. Further, since there is no method for correcting the inclination of the captured image, it is not possible to associate the XY coordinates of the work point with the polar coordinates, and the XY coordinate data (Xn, Yn) for processing the work object can be used for the teaching work of the work point. There is a problem that offline teaching cannot be done using. Furthermore, since the XY coordinates of the work points and the polar coordinates cannot be associated with each other, even if the work points are arranged at equal pitches, it is not possible to perform teaching by numerical input, and teaching is performed for all work points. There is also the problem of having to do the work.

The present invention has been invented to solve the above problems. A swivel arm provided with a working unit is attached to the single-axis robot, and the origin axis of the polar coordinates of the swivel arm is positioned on the axial coordinates of the single-axis robot. A storage unit that stores the work point of the work object as a composite coordinate (Yyn, θn) consisting of the axial coordinate Yyn when the single-axis robot moves and swivels, and the polar coordinate θn where the swivel angle of the swivel arm is θn. A storage unit that stores the swivel radius Rt up to the work unit that swivels integrally with the swivel arm, and coordinate conversion for converting the combined coordinates (Yyn, θn) into the work axis XY coordinates (Xtn, Ytun) of the work unit. A unit is provided in a control device, and the control device controls the axis movement and the turning movement based on the work axis XY coordinate data (Xtn, Ytun). According to this configuration, since the origin axis of the polar coordinates of the swivel arm matches the axis coordinates of the single-axis robot, the XY coordinates including the X-axis coordinates or the Y-axis coordinates of the single-axis robot are associated with the polar coordinates of the swivel arm. It is possible to use a known polar coordinate conversion formula when converting the composite coordinates of each work point into XY coordinates and vice versa. As a result, even if the work object becomes large and the number of work points becomes enormous, the XY coordinate data for processing can be used when processing the work point on the work object, and offline teaching of the work point can be performed. Not only can it be performed, but when the work points are arranged at equal pitches, teaching can be performed by inputting numerical values, and the teaching work can be performed easily and in a short time.

Further, in the present invention, the work point of the work object is set as a composite coordinate (Yyn, θn) composed of the axial coordinate Yyn when the single-axis robot moves and swivels, and the polar coordinate θn where the swivel angle of the swivel arm is θn. With respect to the storage unit for storing, the storage unit for storing the swivel radius Rt to the work unit that swivels integrally with the swivel arm, and the swivel radius Rc to the CCD camera for detecting the work point, and the rotation center of the swivel arm. A storage unit that stores the mounting angle θtc between the work unit and the CCD camera, a coordinate conversion unit that converts the combined coordinates (Yyn, θn) into work axis XY coordinates (Xtn, Ytun), and the work axis XY coordinates ( The control device is provided with a coordinate conversion unit that converts (Xtn, Ytun) into camera axis composite coordinates (Yycn, θcn), and this control device makes it possible to move the CCD camera to the work point. .. According to this configuration, in addition to the above-mentioned effect, the work point given by the composite coordinates (Yyn, θn) can be converted not only into the work axis XY coordinates (Xtn, Ytun), but also into the CCD camera axis XY coordinates. Further, the camera axis XY coordinates can be converted into the camera axis composite coordinates (Ycn, θcn), and the coordinate conversion according to the desired work can be easily performed.

Further, the control device according to the present invention captures the work point by actually photographing the work point with the image pickup origin with the work axis XY coordinates (Xtn, Ytun) of the work point as the image pickup origin on the image pickup coordinates. The image correction unit for calculating the corrected work axis XY coordinates (Xtfn, Ytfn) of the work point from the difference between the work point and the imaged XY coordinates in the captured image is further provided, and the above-mentioned is based on the corrected work axis XY coordinates. It is desirable to have a configuration for controlling the axial movement and the turning movement. In this case, even if the captured image of the CCD camera that captures the work point in the captured image is tilted with respect to the axial coordinate Yyn due to the rotation of the swivel arm, the correction coordinates of the work point from the imaging origin are calculated on the captured image. This can be converted from the inclination of the single-axis robot with respect to the axis coordinate Yyn to the XY coordinates having the axis coordinate Yyn, and can be reflected in the XY coordinates of the work point. Further, this enables rough teaching of work points, and the teaching work can be easily performed.

The imaging correction unit according to the present invention includes an image processing unit that calculates unprocessed correction coordinates (Cxmn, Cymn) from the imaging origin and the imaging coordinates of the working point in the captured image, and the imaging coordinates with respect to the origin axis of the polar coordinates. The correction coordinates of the XY coordinates are calculated from the inclination θn of the above and the unprocessed correction coordinates (Cxmn, Cymn), converted into the corrected camera axis XY coordinates (Xcfn, Ycfn), and this is converted into the corrected work axis XY coordinates (Xtfn, Cymn). It is desirable to have a configuration of Ytfn).

The single-axis robot with a swivel arm according to the present invention has any of the above configurations, and has axis coordinates Yyn, composite coordinates (Yyn, θn) and camera axis composite coordinates (Yyn, θcn) in the configuration, respectively. It is characterized by having a configuration in which the coordinates Xxn, the composite coordinates (Xxn, θn), and the camera axis composite coordinates (Xxcn, θcn) are replaced. With this configuration, the origin axis of the polar coordinates of the swivel arm can be positioned on the axis coordinate Xxn of the single-axis robot, so that the same effect as when the origin axis of the polar coordinates of the swivel arm is arranged at the axis coordinate Yyn can be obtained. ..

Further, in the present invention, among the work points stored in advance for the work object, the XY coordinates of the three work points T1, T2, and T3 located apart from each other are sequentially called one by one, and the work point T1 is called. , T2, T3 are captured in the captured image of the CCD camera, the captured XY coordinates of the working points T1, T2, T3 are corrected from the captured coordinates in the captured image and calculated as the corrected camera axis XY coordinates, and these are used as reference points. It is stored as P1, P2, P3, and a robot control unit that positions the work unit based on the corrected camera axis XY coordinates and drives the work unit, and after calculating three reference points or completing a predetermined work. , Sequentially call the XY coordinates of the work points, replace them with non-Cartesian coordinates consisting of two adjacent work points T1, T2, and T3 corresponding to the reference points, and at the same time, refer to the three reference points P1. , P2, P3 are equipped with a coordinate conversion unit that replaces corrected non-Cartesian coordinates with a line segment connecting two adjacent points in the control device, and this control device makes it possible to handle the inclination of the work object. It is supposed to be. According to this configuration, when there are a large number of work points, the work unit is operated while correcting the coordinates of the first three work points, and when the coordinate calculation of the three work points or the predetermined work is completed, the work is sequentially performed. The XY coordinates of the points are called, and these are non-Cartesian coordinates consisting of a line connecting the two adjacent work points T1, T2, and T3 of the three points, and the adjacent 2 of the reference points of the three points. It can be replaced with corrected non-Cartesian coordinates consisting of line segments connected by individual reference points, and the XY coordinates of the fourth and subsequent work points can be sequentially corrected without wasting time.

In addition, the present invention sequentially sets the XY coordinates of two work points T1 and T2 located away from the base point such as the origin of the XY coordinates among the work points stored in advance for the work object. By calling, the work points T1 and T2 are captured in the captured image of the CCD camera, the captured XY coordinates of the work points T1 and T2 are corrected from the captured coordinates in the captured image, and the corrected camera axis XY coordinates are calculated. Are stored as reference points P1 and P2, and a robot control unit that positions the work unit based on the corrected camera axis XY coordinates and drives the work unit, and after calculating two reference points or completing a predetermined work. Later, the XY coordinates of the work points are sequentially called, and these are replaced with non-Cartesian coordinates consisting of the work points T1 and T2 corresponding to the reference points and the line segment connecting the base points, and the two reference points P1 and P2. The control device is provided with a coordinate conversion unit that replaces the corrected non-Cartesian coordinates with a line segment connecting the base points, and the control device makes it possible to deal with the inclination of the work object. According to this configuration, the corrected non-orthogonal coordinates can be configured by the line segment connecting the reference points P1 and P2 of the two points and the base point, so that the corrected non-orthogonal coordinates can be replaced from the third and subsequent points. The time required for the minute XY coordinate conversion can be shortened.

The coordinate conversion unit according to the present invention can easily replace the work points after the fourth point from the non-Cartesian coordinates consisting of three work points to the corrected non-Cartesian coordinates consisting of three reference points (two points). (The same applies to the reference point), the distribution ratio of each line segment is calculated by using the coordinate points on each coordinate axis of the non-Cartesian coordinates as the distribution point of each line segment, and the distribution point coordinates of the coordinate axes of the corrected non-Cartesian coordinates are calculated from the distribution ratio. Is desirable, and the corrected XY coordinates of the work point are calculated from the distribution point coordinates.

It is desirable that the working unit according to the present invention is a screw tightening unit and is a screw tightening robot with a swivel arm having the above-described configuration. In this case, the time required for the teaching work of the work point can be shortened, and the total time required for fastening the work object can be significantly shortened.

According to the present invention described above, not only can the XY coordinates of the work point be easily converted into the composite coordinates consisting of the axis coordinates of the single-axis robot and the polar coordinates of the swivel arm, but also the work point is attached to the swivel arm with a CCD camera. It is possible to provide a uniaxial robot with a swivel arm and a screw tightening robot with a swivel arm that can perform a predetermined operation while correcting the XY coordinates of the above.

It is explanatory drawing which cut out a part which explains the coordinate transformation of the work point of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. The block diagram which shows the whole structure of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. The block diagram explaining the storage part of the control device of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. The plan view explaining the operating range of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. FIG. 3 is a plan view of a main part for explaining the positional relationship between the screw tightening unit and the CCD camera when calculating the camera axis composite coordinates of the CCD camera from the XY coordinates of the screw tightening unit according to the embodiment of the present invention. The flowchart explaining the setting operation of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. The first-stage flowchart explaining the tightening simultaneous camera correction operation of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. The second-stage flowchart explaining the tightening simultaneous camera correction operation of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. The first-stage flowchart for explaining the simultaneous tightening XY coordinate conversion operation of the screw tightening robot with a swivel arm according to the embodiment of the present invention. A second-stage flowchart illustrating a simultaneous tightening XY coordinate conversion operation of a screw tightening robot with a swivel arm according to an embodiment of the present invention. A third-stage flowchart illustrating a simultaneous tightening XY coordinate conversion operation of a screw tightening robot with a swivel arm according to an embodiment of the present invention. A fourth-stage flowchart illustrating a simultaneous tightening XY coordinate conversion operation of a screw tightening robot with a swivel arm according to an embodiment of the present invention. A fifth-stage flowchart illustrating a simultaneous tightening XY coordinate conversion operation of a screw tightening robot with a swivel arm according to an embodiment of the present invention. The operation explanatory drawing explaining the teaching operation at the time of setting operation of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. The explanatory view of the setting work which sets the imaging origin of the screw tightening robot with a swivel arm which concerns on embodiment of this invention. An enlarged view of a main part of FIG. The explanatory view explaining the non-orthogonal coordinate conversion of the tightening simultaneous XY coordinate conversion operation which concerns on embodiment of this invention. The explanatory view explaining the corrected non-orthogonal coordinate conversion of the tightening simultaneous XY coordinate conversion operation which concerns on embodiment of this invention.

(Embodiment)
Hereinafter, a screw tightening robot with a swivel arm, which is an example of a single-axis robot with a swivel arm according to an embodiment of the present invention, will be described with reference to the drawings. As shown in FIG. 2, reference numeral 1 denotes a screw tightening robot with a swivel arm, which comprises a single-axis robot 3 capable of moving forward and backward with respect to the base 2 and a swivel arm 4 attached to the tip of the single-axis robot 3. Have. A screw tightening unit 5 as an example of a working unit and a CCD camera 6 are attached to the tip of the swivel arm 4. The single-axis robot 3 is arranged so as to extend in the Y-axis direction of the XY coordinate plane, and is driven by a Y-axis motor (not shown) to move the axis to a predetermined position. There is. Further, the single-axis robot 3 is configured to move in the (−) direction when moving forward and in the (+) direction when moving backward, and to change its Y-axis coordinate Yyn.

The swivel arm 4 is configured to swivel in response to the rotation of the θ-axis motor 7 attached to the tip of the single-axis robot 3, and the swivel angle of the swivel arm 4 is θn as shown in FIG. As the polar coordinates θn, the screw tightening unit 5 at the tip thereof is configured to be swiveled to the left in the θ (+) direction and to the right to swivel in the θ (−) direction. As a result, the screw tightening unit 5 is positioned by the composite coordinates (Yyn, θtn) consisting of the bit-axis coordinates Yynt and the bit-axis polar coordinates θtn of the single-axis robot 3 described above (hereinafter, the coordinates related to the bit axes are "". "T" is added). Further, the swivel arm 4 is arranged so that the θ origin axis of its polar coordinate θtn coincides with the Y-axis coordinate Yy of the single-axis robot 3, and the swivel radius from the rotation center of the swivel arm 4 to the screw tightening unit 5 is set. When it is set to Rt, the combined bit axis coordinates (Yyn, θtn) of the screw tightening unit 5 are configured to be converted into bit axis XY coordinates (Xtn, Ytn) by the following XY coordinate conversion formula.

Xtn = Rt * sin (θtn)

Ytn = Yyntn-Rt * cos (θtn)

As shown in FIG. 5, the screw tightening unit 5 and the CCD camera 6 are attached so as to form an attachment angle θtc with respect to the rotation center of the swivel arm 4, from the rotation center of the swivel arm to the CCD camera 6. When the turning radius is Rc, the combined coordinates of the camera axis (Yycn, θcn) of the CCD camera 6 are calculated from the above-mentioned bit axis XY coordinates (Xtn, Ytun) by the following combined coordinate conversion formula. (Hereinafter, "c" is added to the coordinates related to the camera axis).

Yycn = Ytn + Rc * cos (acos (Xtn / Rc))

θcn = acos (Xtn / Rc) -θct

The screw tightening unit 5 at the tip of the swivel arm 4 is attached to a Z-axis unit 8 that moves up and down in the Z-axis direction by a Z-axis motor (not shown), and is positioned at a preset height position. It is configured so that an object to be fastened (not shown) can be attached by tightening a screw to a predetermined work object W (see FIG. 2).

As shown in FIG. 1, the CCD camera 6 is attached to detect the work point Tn of the work object W, and when the work point Tn is called by the composite coordinates (Yycn, θcn) of the CCD camera 6, the work point Tn is called. The CCD camera 6 is configured to move above the working point Tn so as to capture the captured image and capture the captured image into the image processing unit 17 described later.

The screw tightening robot 1 with a swivel arm includes a single-axis robot 3, a swivel arm 4, and a control device 9 for controlling a screw tightening unit 5. The control device 9 includes a robot control unit 12 having an operation mode selection unit 10 and an operation unit 11 inside, and Y-axis motor drive units 13 and θ that drive the Y-axis motor, the θ-axis motor 7, and the Z-axis motor, respectively. The shaft motor drive unit 14, the Z-axis motor drive unit 15, the storage unit 16 that stores various information for performing predetermined tightening, the image processing unit 17 that captures the captured image of the CCD camera 6, and the screw tightening unit control unit 18. I have. The operation mode selection unit 10 has a set operation mode, a tightening simultaneous camera correction mode, and a tightening simultaneous XY coordinate conversion mode. In the setting operation mode, a setting operation program described later that stores necessary data before the tightening work can be selected, and in the simultaneous tightening camera correction mode, the position of the work point is corrected by the CCD camera 6 and tightening is performed at the same time. It is configured so that the camera correction program can be selected. Further, the tightening simultaneous XY coordinate conversion mode is configured so that a tightening simultaneous XY coordinate conversion program that sequentially converts the XY coordinates of the working point into synthetic coordinates at the same time as tightening can be selected.

The operation unit 11 can output a tightening start signal in the tightening simultaneous camera correction mode and the tightening simultaneous XY coordinate conversion mode, and when teaching the work point Tn in the setting operation mode and the tightening simultaneous camera correction mode. It is configured to be able to output a camera axis storage command signal, a bit axis storage command signal, and a teaching completion signal.

When the image processing unit 17 receives an image capture command signal from the robot control unit 12 in the set operation mode, the image processing unit 17 captures the captured image of the CCD camera 6, and uses the coordinates of the center of the work point T1 in the captured image as the imaging origin. It is configured to be remembered. Further, when the image processing unit 17 receives an image capture command signal in the tightening simultaneous camera correction mode and the tightening simultaneous XY coordinate conversion mode, respectively, the image processing unit 17 calculates the center coordinates of the work point Tn in the captured image and the imaging origin. It is configured to calculate the unprocessed correction coordinates (Cxm1, Cym1) from the above and output the unprocessed correction coordinates (Cxm1, Cym1) to the robot control unit 12. Further, when the image processing unit 17 receives the imaging origin setting signal in the simultaneous tightening XY coordinate conversion mode, the image processing unit 17 captures the captured image of the CCD camera 6 and stores the coordinates of the center of the work point T1 in the captured image as the imaging origin. At the same time, it is configured to output an image pickup origin setting completion signal to the robot control unit 12.

As shown in FIG. 3, the storage unit 16 has an operation program storage unit 19 that stores a setting operation program, a tightening simultaneous camera correction program, and a tightening simultaneous XY coordinate data conversion program. Further, the storage unit 16 stores the work point Tn as the bit axis composite coordinates (Yynt, θtn) and the bit axis composite coordinate storage unit 20, and the work point Tn as the bit axis XY coordinates (Xtn, Ytun). The XY coordinate storage unit 21, the camera axis composite coordinate storage unit 22 that stores the work point Tn as the camera axis composite coordinates (Yycn, θcn), and the corrected bit axis XY coordinates (Xtfn, Ytfn) that have been position-corrected by the CCD camera 6. ) Is stored in the corrected bit axis XY coordinate storage unit 23, and the corrected bit axis composite coordinates (Yyn, θtn) converted from the corrected bit axis XY coordinates (Xtfn, Ytfn) are stored. It has a storage unit 24 and a Z-axis coordinate (Ztn) storage unit 25 that stores the height position of the screw tightening unit 5. The camera axis composite coordinates (Yycn, θcn) are sequentially calculated from the bit axis composite coordinates (Yyn, θtn) by the above-mentioned XY coordinate conversion formula and composite coordinate conversion formula, and are stored in the camera axis composite coordinate storage unit 22. To.

Further, the storage unit 16 has a bit shaft turning radius Rt storage unit 26 that stores the bit shaft turning radius Rt in advance, a camera shaft turning radius Rc storage unit 27 that stores the camera shaft turning radius Rc in advance, and rotation of the turning arm. It has a camera mounting angle θct storage unit 28 that stores in advance the mounting angle θtc between the screw tightening unit 5 and the CCD camera 6 with respect to the center.

The screw tightening unit control unit 18 includes a bit motor drive unit 30, a torque determination unit 31, a torque control unit 32, and a torque storage unit 33 that stores a set torque corresponding to each work point. When the screw tightening unit control unit 18 receives a drive command signal from the robot control unit 12, the screw tightening unit control unit 18 calls a set torque according to the work point, operates the bit motor drive unit 30, and tightens with the set tightening torque. At the same time, the torque determination unit 31 is configured to determine the quality.

The above-mentioned setting operation program is for teaching the work point Tn and setting the imaging origin of the captured image of the CCD camera 6, and as shown in FIG.

P1) Wait for the input of the bit axis storage command signal from the operation unit 11.

P2) When the bit-axis storage command signal is input, the Y-axis coordinates Yyn are calculated from the Y-axis motor, and the polar coordinates θn are calculated from the θ-axis motor 7, and these are stored as bit-axis composite coordinates (Yyn, θtn) (n is incremented (incremented (n)). Initial value = 1)).

P3) It is determined whether or not a teaching completion signal is input from the operation unit 11, and when there is no input of the signal, the process returns to P1.

P4) When the teaching completion signal is input, the input of the camera axis storage command signal from the operation unit 11 is awaited.

P5) The image capture command signal is output to the image processing unit 17.

P6) End It is configured to execute the steps P1 to P6 above.

In the tightening simultaneous camera correction program, when the tightening start signal is output from the operation unit 11 in the tightening simultaneous camera correction mode, as shown in FIGS. 7 and 8, as shown in FIGS.

Q1) The bit-axis composite coordinates (Yyn, θtn) of the work point Tn are read from the bit-axis composite coordinate storage unit 20 (initial value n = 1).

Q2) The bit-axis composite coordinates (Yyn, θtn) are converted into XY coordinates by the following XY coordinate conversion formula, and stored as the bit-axis XY coordinates (Xtun, Ytun).

Xtn = Rt * sin (θtn)

Ytun = Yyn-Rt * cos (θtn)

Q3) From the bit axis XY coordinates (Xtn, Ytun), the camera axis composite coordinates (Yycn, θcn) are calculated and stored by the following composite coordinate conversion formula.

Yycn = Ytn + Rc * cos (acos (Xtn / Rc))

θcn = acos (Xtn / Rc) -θct

Q4) Based on the camera axis composite coordinates (Yycn, θcn), drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7.

Q5) Wait for the input of the positioning completion signal from the Y-axis motor drive unit 13 and the θ-axis motor drive unit 14.

Q6) When the positioning completion signal is input, the image capture command signal is output to the image processing unit 17.

Q7) Wait for the input of the unprocessed correction coordinates (Cxmn, Cymn) from the image processing unit 17.

Q8) The slope θn of the imaging coordinates with respect to the XY coordinates and the unprocessed correction coordinates (Cxmn,
The correction coordinates (ΔXn, ΔYn) on the XY coordinates are calculated from Cymn).

Q9) From the corrected coordinates (ΔXn, ΔYn) and the camera axis XY coordinates of the work point Tn, that is, the bit axis XY coordinates (Xtn, Ytun), the corrected camera axis XY coordinates, that is, the corrected bit axis XY coordinates (Xtfn, Ytfn) are obtained. It is calculated and stored in the corrected bit axis XY coordinate storage unit 23 (hereinafter, “f” is added to the corrected XY coordinates).

Q10) From the corrected bit axis XY coordinates (Xtfn, Ytfn) of the work point Tn, the corrected bit axis composite coordinates (Yytfn, θtfn) are calculated by the following composite coordinate conversion formula, and the corrected bit axis composite coordinate storage unit 24 Remember in.

Yytfn = Ytfn + Rt * cos (asin (Xtfn / Rt))

θtfn = asin (Xtfn / Rt)

Q11) Read the corrected bit axis composite coordinates (Yytfn, θtfn).

Q12) Based on the corrected bit-axis composite coordinates (Yytfn, θtfn), drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7.

Q13) Wait for the input of the positioning completion signal from the Y-axis motor drive unit 13 and the θ-axis motor drive unit 14.

Q14) When the positioning completion signal is input, the screw tightening unit drive command (Z-axis lowering / bit motor drive) signal is output to the screw tightening unit control unit 18.

Q15) Wait for the input of the tightening completion signal from the screw tightening unit control unit 18.

Q16) When the tightening completion signal is input, it is determined whether or not the tightening of all work points is completed, and when the tightening of all work points is not completed, n = n + 1 and the process returns to Q1.

Q17) When all work points have been tightened, the end.
It is configured to execute the steps Q1 to Q17. The next work point is called after the tightening at the current work point is completed, but it may be after the corrected camera axis composite coordinates are calculated.

When the tightening start signal is output from the operation unit 11 in the tightening simultaneous XY coordinate data conversion mode, the tightening simultaneous XY coordinate data conversion program is as shown in FIGS. 9 to 13.

R1) The XY coordinate data (Xn, Yn) on the processing of all the work points Tn of the work object W are read into the bit axis XY coordinate storage unit 21.

R2) Wait for the input of the camera axis storage command signal from the operation unit 11.

R3) The image capture command signal is output to the image processing unit 17.

R4) Wait for the imaging origin setting completion signal from the image processing unit 17.

R5) Among the work points, three distant points (T1, T2, T3) are selected and these are temporarily stored.

R6) The coordinates (X1, Y1) of the work point T1 are converted into bit-axis composite coordinates (Yyt1, θt1) by the following composite coordinate conversion formula.

Yyt1 = Y1 + Rt * cos (asin (X1 / Rt))

θt1 = asin (X1 / Rt)

R7) The camera axis composite coordinates (Yyc1, θc1) are calculated from the coordinates (X1, Y1) of the work point T1 by the following composite coordinate conversion formula, and stored in the camera axis composite coordinate storage unit 22.

Yyc1 = Yt1 + Rc * cos (acos (Xt1 / Rc))

θc1 = acos (Xt1 / Rc) -θtc

R8) Based on the combined camera axis coordinates (Yyc1, θc1), drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7.

R9) Wait for the input of the positioning completion signal from the Y-axis motor drive unit 13 and the θ-axis motor drive unit 14.

R10) When the positioning completion signal is input, the image capture command signal is output to the image processing unit 17.

R11) Waits for input of unprocessed correction coordinates (Cxm1, Cym1) from the image processing unit 17.

R12) The slope θ1 of the imaging coordinates with respect to the XY coordinates and the unprocessed correction coordinates (Cxm1,
From Cym1), the correction coordinates (ΔX1, ΔY1) on the XY coordinates are calculated.

R13) From the correction coordinates (ΔX1, ΔY1) and the camera axis XY coordinates of the work point T1, that is, the coordinates of the work point T1 (X1, Y1), the corrected camera axis XY coordinates, that is, the corrected bit axis XY coordinates (Xtf1, Ytf1). Is calculated and stored in the corrected bit axis XY coordinate storage unit 23.

R14) From the corrected bit axis XY coordinates (Xtf1, Ytf1) of the work point T1, the corrected bit axis composite coordinates (Yytf1, θtf1) are calculated by the following composite coordinate conversion formula, and the corrected bit axis composite coordinate storage unit 24 Remember in.
Yytf1 = Ytf1 + Rt * cos (asin (Xtf1 / Rt))
θtf1 = asin (Xtf1 / Rt)

R15) Based on the corrected bit-axis composite coordinates (Yytf1, θtf1), drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7.

R16) Waits for the input of the positioning completion signal from the Y-axis motor drive unit 13 and the θ-axis motor drive unit 14.

R17) When the positioning completion signal is input, the screw tightening unit drive command (Z-axis lowering / bit motor drive) signal is output to the Z-axis motor drive unit 15.

R18) Wait for the input of the tightening completion signal.

(Hereinafter, the steps R6 to R18 are referred to as tightening STP).

R19) It is determined whether or not the tightening completion signal of the work point T3 is input, and when the tightening completion signal of the work point T3 is not input, the tightening STP is sequentially executed for the work points T2 and T3. (Replace the number in each code according to the work point number).

R20) When the tightening completion signal of the work point T3 is input, the bit axis XY coordinate storage unit 21 sends the three bit axis XY coordinates (Xt1, Yt1), (Xt2, corresponding to the work points T1, T2, T3). Yt2), (Xt3, Yt3) are called.

R21) From the bit axis XY coordinates (Xt1, Yt1), (Xt2, Yt2), (Xt3, Yt3) of the three points, the slope of the coordinate axis of the non-Cartesian coordinates consisting of the line segment connecting the two adjacent points is calculated. Temporarily memorize.

R22) The bit axis XY coordinates (Xtn, Ytun) of the nth working point Tn are called (initial value 4 of n).

R23) The distribution ratio of each line segment by the intersections Pzna and Pznb of the line segment (coordinate axis) formed by the work points T1 and T2 and T2 and T3 and the parallel line segment passing through the work point Tn and intersecting with each line segment is calculated. Temporarily memorize.

R24) The corrected bit axis XY coordinates (Xtf1, Ytf1), (Xtf2, Ytf2), and (Xtf3, Ytf3) of the work points T1, T2, and T3 are called.

R25) From the corrected bit axis XY coordinates (Xtf1, Ytf1), (Xtf2, Ytf2), (Xtf3, Ytf3) of three points, the coordinate axes of the corrected non-orthogonal coordinates consisting of a line segment connecting two adjacent points are described above. The XY coordinates (Xzna, Yzna) and (Xznb, Yznb) of the distribution points Pzfna and Pzfnb to be distributed according to the distribution ratio are calculated and temporarily stored.

R26) Distribution point Pzna. The intersection where two parallel line segments passing through Pznb intersect is calculated as the corrected bit axis XY coordinates (Xtfn, Ytfn) of the working point Tn and temporarily stored.

R27) From the corrected bit axis XY coordinates (Xtfn, Ytfn) of the work point Tn, the corrected bit axis composite coordinates (Yytfn, θtfn) are calculated and stored by the following composite coordinate conversion formula.

Yyfn = Ytfn + Rt * cos (asin (Xtfn / Rt))

θtfn = asin (Xtfn / Rt)

R28) Based on the corrected bit-axis composite coordinates (Yytfn, θtfn), drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7.

R29) Wait for the input of the positioning completion signal from the Y-axis motor drive unit 13 and the θ-axis motor drive unit 14.

R30) When the positioning completion signal is input, the screw tightening unit drive command (Z-axis lowering / bit motor drive) signal is output to the Z-axis motor drive unit 15.

R31) Wait for the input of the tightening completion signal.

R32) It is determined whether or not the tightening of all work points is completed, and when the tightening of all work points is not completed, n = n + 1 and the process returns to R22.

R33) End when tightening of all work points is completed.
It is configured to execute the steps R1 to R33.

There are various calculation methods for calculating the distribution ratio from the four points in step R23, but although not described in detail, two straight lines (A1 to A3, A2) consisting of the four points (A1, A2, A3, A4) are used. By adopting the method of applying the outer product to obtain the intersection of ~ A4), the same calculation can be performed for the combination of the other four points.

Steps Q2, Q3, and Q10 of the above-mentioned simultaneous tightening camera correction operation program, and step R6 of the simultaneous tightening XY coordinate conversion operation program. R7, R14, R21 to R24 constitute a coordinate conversion unit 29 when the robot control unit 12 operates. Further, steps Q7 to Q10 of the simultaneous tightening camera correction operation program and steps R11 to R14 of the simultaneous tightening XY coordinate conversion operation program constitute an image pickup correction unit. Further, although the coordinate conversion unit 29 and the image pickup correction unit 34 are configured in the operation program, they may be configured in the robot control unit 12 in advance as a calculation unit (not shown).

In the screw tightening robot with a swivel arm, when the set operation mode is selected by the operation mode selection unit 10 prior to tightening to the work object W, the operation program storage unit 19 calls the set operation program to the robot control unit 12. The robot control unit 12 is controlled by this setting operation program. That is, as shown in FIG. 14, the operator manually moves the uniaxial robot 3 and the swivel arm 4 to move the screw tightening unit 5 onto the arbitrary work point T1. After that, when a bit-axis storage command signal is input from the operation unit 11, the Y-axis coordinate Yyn is read from the Y-axis motor and the polar coordinate θn is read from the θ-axis motor 7 by this bit-axis storage command signal, and these are the bit-axis composite coordinates ( It is stored as Yytn, θtn) (n is incremented. Initial value n = 1).

This teaching operation is repeated until the operator inputs a teaching completion signal from the operation unit 11.

After teaching of all work points is completed and the operator inputs a teaching completion signal from the operation unit 11, the CCD camera 6 is moved onto an arbitrary work point T1 as shown in FIG. 15, and the camera axis is stored from the operation unit 11. Input the command signal. By this camera axis storage command signal, as shown in FIG. 16, the captured image of the CCD camera 6 is taken into the image processing unit 17, and the coordinates of the center of the work point T1 are set as the imaging origin of the imaging coordinates formed by the captured image. ..

After that, when the tightening simultaneous camera correction mode is selected by the operation mode selection unit 10, the tightening simultaneous camera correction operation program is called from the operation program storage unit 19 to the robot control unit 12, and the robot control unit 12 performs this tightening. It is controlled by the simultaneous camera correction operation program. That is, when the operator inputs the tightening start signal from the operation unit 11, the position of the taught work point Tn is called in order from the initial value n = 1 as the bit axis composite coordinates (Yytn, θtn). From the combined bit axis coordinates (Yyt1, θt1), the bit axis XY coordinates (Xt1, Yt1) are
Xt1 = Rt * sin (θt1)
Yt1 = Yyt1-Rt * cos (θt1)
Is calculated as (see FIG. 4).

When the bit axis XY coordinates (Xt1, Yt1) are calculated, the camera axis composite coordinates (Yyc1, θc1) are derived from the XY coordinates.
Yyc1 = Yt1 + Rc * cos (acos (Xt1 / Rc))
θc1 = acos (Xt1 / Rc) -θtc
Is calculated and stored in the camera axis composite coordinate storage unit 22. Explaining the calculation of the combined camera axis coordinates (Yyc1, θc1) with reference to FIG. 5, when n = 1, the turning angle of the CCD camera 6 for moving the CCD camera 6 to the X coordinate Xt1 of the work point T1 is acos. Since it is calculated as (Xtn / Rc), the turning angle θc1 of the turning arm 4 at this time is obtained as θc1 = acos (Xt1 / Rc) −θct. Further, since the Yy coordinate component is added by the rotation of the CCD camera 6, Yyc1 is obtained as Yt1 + Rc * cos (acos (Xt1 / Rc)).

When the camera axis composite coordinates (Yyc1, θc1) are calculated, drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7 based on the composite coordinates, and the Y-axis motor and θ The shaft motor 7 is driven, and the CCD camera 6 is positioned at the teaching position of the work point T1. Along with this, a positioning completion signal is input from the Y-axis drive motor drive unit 13 and the θ-axis motor drive unit 14, an image capture command signal is output to the image processing unit 17 by this positioning completion signal, and the work point T1 is set. The captured image of the CCD camera 6 is captured by the image processing unit 17. At the same time, as shown in FIG. 1, the image processing unit 17 calculates the center coordinates of the work point T1 on the imaging coordinates formed by the captured image, and between the center coordinates and the imaging origin set in the set operation mode. The unprocessed correction coordinates (Cxm1, Cym1) of are calculated and output to the robot control unit 12.

When the unprocessed correction coordinates (Cxm1, Cym1) are input from the image processing unit 17, the correction coordinates (ΔX1, ΔX1,) on the XY coordinates are obtained from the inclination θn of the imaging coordinates with respect to the XY coordinates and the unprocessed correction coordinates (Cxm1, Cym1). ΔY1) is calculated. From the correction coordinates (ΔX1, ΔY1) and the camera axis XY coordinates of the work point T1, that is, the bit axis XY coordinates (Xt1, Yt1), the corrected camera axis XY coordinates of the work point T1, that is, the corrected bit axis XY coordinates (Xtf1,). Ytf1) is calculated and stored in the corrected bit axis XY coordinate storage unit 23.

From the corrected bit axis XY coordinates (Xtf1, Ytf1), the corrected bit axis composite coordinates (Yytf1, θtf1) are calculated by the following composite coordinate conversion formula and stored in the corrected bit axis composite coordinate storage unit 24.

Yyf1 = Ytf1 + Rt * cos (asin (Xtf1 / Rt))

θtf1 = asin (Xtf1 / Rt)

When the corrected bit-axis composite coordinates (Yytf1, θtf1) are calculated, drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7 based on the composite coordinates, and the single-axis robot 3 and the swivel arm 4 move to position the screw tightening unit 5 directly above the work point T1, and in response to the positioning completion signal, the screw tightening unit drive command (Z-axis lowering / bit motor drive) signal is screwed. It is sent to the unit control unit 18.

When the tightening completion signal is received from the screw tightening unit control unit 18, it is determined whether or not the tightening of all work points is completed, and when the tightening of all work points is not completed, the work points Tn are sequentially called. The simultaneous tightening camera correction operation can be performed for all work points in the same manner.

Next, the simultaneous tightening XY coordinate conversion operation will be described. When tightening the work object W having the XY coordinates at the time of machining the work point, when the work object W is placed in the work area of the screw tightening robot 1 with a swivel arm, the operation mode selection unit 10 tightens the work object W. Simultaneous XY coordinate conversion mode is selected. As a result, the simultaneous tightening XY conversion operation program is called to the robot control unit 12, and the robot control unit 12 is controlled by this simultaneous tightening XY conversion operation program. That is, when the tightening start signal is input from the operation unit 11, the XY coordinates at the time of the processing are taken into the bit axis XY coordinate storage unit 21.

Subsequently, the operator moves the CCD camera 6 onto the arbitrary work point T1 and inputs the camera axis storage command signal from the operation unit 11. By this camera axis storage command signal, the captured image of the CCD camera 6 is taken into the image processing unit 17, and the center coordinates of the work point T1 are set as the imaging origin of the captured coordinates formed by the captured image.

After that, when the imaging origin setting completion signal is input from the image processing unit 17, the XY coordinates (X1, Y1) of three points (T1, T2, T3) at distant positions from the bit axis XY coordinates of all the working points ), (X2, Y2), (X3, Y3) are selected and temporarily stored.

Subsequently, the coordinates (X1, Y1) of the work point T1 are called, and these are converted into bit-axis composite coordinates (Yyt1, θt1) by the following composite coordinate conversion formula and stored in the bit-axis composite coordinate storage unit 20. To.

Yyt1 = Y1 + Rt * cos (asin (X1 / Rt))

θt1 = asin (X1 / Rt)

When the bit axis composite coordinates (Yyt1, θt1) are calculated, the camera axis composite coordinates (Yyc1, θc1) are calculated from the composite coordinates by the following composite coordinate conversion formula and stored in the camera axis composite coordinate storage unit 22. (See Fig. 5).
Yyc1 = Yt1 + Rc * cos (acos (Xt1 / Rc))
θc1 = acos (Xt1 / Rc) -θtc

At the same time, based on the combined camera axis coordinates (Yyc1, θc1), drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7, and the single-axis robot 3 and the swivel arm 4 move. The screw tightening unit 5 is positioned above the work point T1. Along with this, a positioning completion signal is input from the Y-axis drive motor drive unit 13 and the θ-axis motor drive unit 14, and an image capture command signal is output to the image processing unit 17 by this positioning completion signal. The captured image is taken into the image processing unit 17. At this time, the image processing unit 17 calculates the center coordinates of the work point T1 as in the case of the simultaneous tightening camera correction operation, and also calculates the unprocessed correction coordinates (Cxm1, Cym1) between the center coordinates and the imaging origin. Then, this is output to the robot control unit 12. The robot control unit 12 calculates the correction coordinates (ΔX1, ΔY1) on the XY coordinates from the unprocessed correction coordinates (Cxm1, Cym1) and the inclination θn of the imaging coordinates with respect to the XY coordinates. From the correction coordinates (ΔX1, ΔY1) and the camera axis XY coordinates of the work point T1, that is, the bit axis XY coordinates (Xt1, Yt1), the corrected camera axis XY coordinates of the work point T1, that is, the corrected bit axis XY coordinates (Xtf1,). Ytf1) is calculated and stored in the corrected bit axis XY coordinate storage unit 23.

Subsequently, the corrected bit axis composite coordinates (Yytf1, θtf1) are calculated from the corrected bit axis XY coordinates (Xtf1, Ytf1) by the following composite coordinate conversion formula, and are stored in the corrected bit axis composite coordinate storage unit 24. To.

Yyf1 = Ytf1 + Rt * cos (asin (Xtf1 / Rt))

θtf1 = asin (Xtf1 / Rt)
At this time, the work point T1 is also stored as the reference point P1.

When the corrected bit-axis composite coordinates (Yytf1, θtf1) are calculated, drive command signals are output to the drive units 13 and 14 of the Y-axis motor and the θ-axis motor 7 based on the composite coordinates, and the single-axis robot 3 and the swivel arm 4 move to position the screw tightening unit 5 directly above the work point T1. Upon completion of this positioning, a positioning completion signal is received from the Y-axis motor drive unit 13 and the θ-axis motor drive unit 14, and a screw tightening unit drive command (Z-axis lowering / bit motor drive) signal is sent to the screw tightening unit control unit 18. It is sent and tightening at work point T1 is started.

When the tightening completion signal is received from the screw tightening unit control unit 18, it is determined whether or not the tightening completion signal is at the work point T3, and when the tightening of the work point T3 is not completed, the work points T2 and T3 are sequentially set. By calling, camera correction of work points T2 and T3 is performed in the same manner as work points T1, these are stored as reference points P2 and P3, and at the same time, tightening is performed at work points T2 and T3.

When the tightening at the work point T3 is completed and the tightening completion signal is input, the bit axis XY coordinates of the work points T1, T2, T3 corresponding to the reference points P1, P2, P3 are input from the bit axis XY coordinate storage unit 21. (Xt1, Yt1), (Xt2, Yt2), (Xt3, Yt3) are called. From the bit axis XY coordinates (Xt1, Yt1), (Xt2, Yt2), (Xt3, Yt3) of these three points, each line segment, that is, each line segment, that is, each The inclination of the coordinate axes is calculated and temporarily stored.

Subsequently, the bit axis XY coordinates (Xt4, Yt4) of the fourth work point T4 are called, and as shown in FIG. 17, the line segment (coordinate axis) formed by the work points T1, T2 and T2, T3 and the work point The distribution ratio of each line segment (coordinate axis) by the intersection points Pz4a and Pz4b with the parallel line segment passing through T4 and intersecting with each line segment is calculated and temporarily stored.

Further, as shown in FIG. 18, from the corrected bit axis XY coordinates (Xtf1, Ytf1), (Xtf2, Ytf2), (Xtf3, Ytf3) which are the XY coordinates of the above-mentioned three reference points P1, P2, P3. A coordinate axis of corrected non-orthogonal coordinates consisting of a line segment connecting two adjacent points is calculated. The coordinate axes are each distributed at the distribution ratio, and the corrected distribution points Pzf4a and Pzf4b are calculated as XY coordinates (Xzf4a, Yzf4a) and (Xzf4b, Yzf4b), respectively, and temporarily stored. The corrected distribution point Pzf4a. The intersection of two parallel line segments that pass through Pzf4b and intersect each line segment is calculated as the corrected bit axis XY coordinates (Xtf4, Ytf4) of the work point T4 and temporarily stored. After that, as in the case of tightening the work points T1, T2, and T3, the corrected bit axis composite coordinates (Yytf4, θtf4) are calculated from the corrected bit axis XY coordinates (Xtf4, Ytf4), and the corrected bit axis composite coordinates are calculated. In addition to being stored in the storage unit 24, the single-axis robot 3 and the swivel arm 4 are driven based on the coordinates, and the screw tightening unit 5 is positioned directly above the work point T4.

When the screw tightening unit 5 is positioned and receives the positioning completion signal from the Y-axis motor drive unit 13 and the θ-axis motor drive unit 14, the screw tightening unit drive command (Z-axis lowering / bit motor drive) signal is sent to the screw tightening unit control unit. Sent to 18.

When the tightening completion signal is input from the screw tightening unit control unit 18, it is determined whether or not the tightening of all work points is completed, and when the tightening of all work points is not completed, the fifth and subsequent work points are sequentially selected. By calling, the tightening simultaneous XY coordinate conversion operation can be performed in the same manner for all work points.

In the case of the above-mentioned simultaneous tightening XY coordinate conversion operation, after the corrected XY coordinates of the three reference points are calculated, the coordinates of the fourth and subsequent points are converted, but the origin of the XY coordinates is used as the reference point. By using the base point, the corrected non-Cartesian coordinates can be constructed by the line connecting the two reference points P1 and P2 and the base point as in the above case, so the corrected non-Cartesian coordinates are replaced from the third and subsequent points. Therefore, the time required for XY coordinate conversion can be shortened accordingly.

Although the above-mentioned single-axis robot 3 is arranged along the Y-axis on the XY coordinates, it may be arranged along the X-axis on the same coordinates. In this case, the Y-axis coordinates Yyn, the composite coordinates (Yyn, θn) and the camera axis composite coordinates (Yyn, θcn) are the axis coordinates Xxn and the composite coordinates (Yyn, θcn), paying attention to the relationship of Y → X and X → −Y, respectively. It may be replaced with Xxn, θn) and camera axis composite coordinates (Xxcn, θcn). Further, when the bit axis XY coordinates (Xtn, Ytun), the corrected bit axis XY coordinates (Xtfn, Ytfn), and other Y axis coordinates are replaced with the X axis coordinates, the X coordinates of each coordinate that needs to be replaced are replaced with the Y coordinates. , The Y coordinate may be replaced with the X coordinate. By these substitutions, the same coordinate transformation as described above becomes possible.

As described above, in the screw tightening robot 1 with a swivel arm of the present invention, the swivel arm 4 provided with the screw tightening unit 5 is attached to the single axis robot 3, and the origin axis of the polar coordinates of the swivel arm 4 is a single axis. It is located on the axis coordinates of the robot 3, and the work point of the work object W is composed of the axis coordinates Yyn when the uniaxial robot 3 moves and swivels, and the polar coordinates θn where the swivel angle of the swivel arm 4 is θn. The bit-axis composite coordinate storage unit 20 that stores as composite coordinates (Yyn, θn), the bit-axis swivel radius Rt storage unit 26 that stores the swivel radius Rt up to the screw tightening unit 5 that swivels integrally with the swivel arm 4, and the above-mentioned The conversion formula for converting the composite coordinates (Yyn, θn) to the bit axis XY coordinates (Xtn, Ytun) of the screw tightening unit 5 is

Xtn = Rt * sin (θn)

Ytun = Yyn-Rt * cos (θn)
The control device 9 is provided with a coordinate conversion unit 29 for calculating the bit axis XY coordinates (Xtn, Ytun) of the screw tightening unit 5, and the control device 9 provides the control device 9 based on the work axis XY coordinate data (Xtn, Ytun). It is characterized by controlling axial movement and turning movement. According to this configuration, since the origin axis of the polar coordinates of the swivel arm 4 matches the axis coordinates of the single-axis robot 3, the XY coordinates including the X-axis coordinates or the Y-axis coordinates of the single-axis robot 3 and the polar coordinates of the swivel arm Can be associated with, and a known polar coordinate conversion formula can be used when converting the composite coordinates of each work point into XY coordinates and in vice versa. As a result, even if the work object W becomes large and the number of work points becomes enormous, the XY coordinate data for processing can be used when processing the work point on the work object W, and the work point can be offline. Not only can teaching be performed, but when work points are arranged at equal pitches, teaching can be performed by numerical input, and teaching work can be performed easily and in a short time.

Further, in the other screw tightening robot 1 with a swivel arm of the present invention, the axial coordinates Yyn and the swivel angle of the swivel arm 4 when the single-axis robot 3 axially moves and swivels the work point of the work object W are set to θn. Bit-axis composite coordinate storage unit 20 that stores as composite coordinates (Yyn, θn) consisting of polar coordinates θn, and bit-axis swivel radius Rt that stores the swivel radius Rt up to the screw tightening unit 5 that swivels integrally with the swivel arm 4. The storage unit 26, the camera axis swivel radius Rc storage unit 27 that stores the swivel radius Rc up to the CCD camera 6 for detecting the work point, the screw tightening unit 5 and the CCD camera 6 with respect to the rotation center of the swivel arm 4. A camera mounting angle θct storage unit 28 that stores the mounting angle θct between the two, a coordinate conversion unit 29 that converts the combined coordinates (Yyn, θn) into bit axis XY coordinates (Xtn, Ytun), and the working axis XY coordinates ( The conversion formula for converting (Xtn, Ytun) to the camera axis composite coordinates (Yycn, θcn),

Xtn = Rt * sin (θn)

Ytun = Yyn-Rt * cos (θn)

Yycn = Ytn + Rc * cos (acos (Xt / Rc))

θn = acos (Xtn / Rc) -θtc
The control device is provided with a coordinate conversion unit 29 for calculating the bit axis XY coordinates (Xtn, Ytun) and the camera axis composite coordinates (Ycn, θcn), and the control device 9 moves the CCD camera 6 to the work point. It is characterized by being able to make it possible. According to this configuration, in addition to the above-mentioned effect, not only the working point given by the composite coordinates (Yyn, θn) can be converted into the bit axis XY coordinates (Xtn, Ytun), but also the bit axis composite coordinates (Yyn, θn) can be converted. It is possible to convert from θn) to the CCD camera axis XY coordinates, and from this camera axis XY coordinates to the camera axis composite coordinates (Ycn, θcn), and it is possible to easily perform coordinate conversion according to the desired work.

The control device 9 according to the embodiment of the present invention uses one work axis XY coordinates (Xtn, Ytun) of the work point as the image pickup origin on the image pickup coordinate, and actually photographs the work point through the image pickup origin and the CCD camera 6. The image correction unit 34 that calculates the corrected work axis XY coordinates (Xtfn, Ytfn) of the work point from the difference from the imaged XY coordinates of the work point in the captured image captured by is further provided, and the corrected work axis XY coordinates are used. The configuration may be such that the axial movement and the turning movement are controlled based on the above. In this case, even if the captured image of the CCD camera 6 that captures the work point in the captured image is tilted with respect to the axial coordinate Yyn due to the rotation of the swivel arm 4, the correction coordinates of the work point from the imaging origin are calculated on the captured image. Then, this can be converted from the inclination of the single-axis robot 3 with respect to the axis coordinate Yyn to the XY coordinates having the axis coordinate Yyn, and can be reflected in the XY coordinates of the work point. Further, this enables rough teaching of work points, and the teaching work can be easily performed.

The imaging correction unit 34 according to the embodiment of the present invention includes an image processing unit 17 that calculates unprocessed correction coordinates (Cxmn, Cymn) from the imaging origin and the imaging coordinates of the working point in the captured image, and the origin of the polar coordinates. A conversion formula for calculating the correction coordinates of the XY coordinates from the inclination θn of the imaging coordinates with respect to the axis and the unprocessed correction coordinates (Cxmn, Cymn) and converting them into the corrected camera axis XY coordinates (Xcfn, Ycfn) is obtained.
Xcfn = Xtn + (Cxmn * cos (θn) + Cymn * sin (θn))
Ycfn = Ytn + (Cxmn * sin (θn) + Cymn * cos (θn))
As a result, a configuration may be provided in which the corrected bit axis XY coordinates (Xtfn, Ytfn) are used. In this case, the CCD camera 6 can be easily attached to the swivel arm 4 without the need for centering work of the CCD camera 6.

The single-axis robot 1 with a swivel arm according to the embodiment of the present invention has any of the above configurations, and the axis coordinates Yyn, the composite coordinates (Yyn, θn) and the camera axis composite coordinates (Yyn, θcn) in the configuration are provided. Is replaced with the axis coordinates Xxn, the composite coordinates (Xxn, θn), and the camera axis composite coordinates (Xxcn, θcn), respectively. With this configuration, the origin axis of the polar coordinates of the swivel arm 4 can be positioned on the axis coordinate Xxn of the single-axis robot 3, so that the same effect as when the origin axis of the polar coordinates of the swivel arm 4 is arranged at the axis coordinate Yyn has the same effect. Is obtained.

Further, in the present invention, among the work points stored in advance with respect to the work object W, the XY coordinates of the three work points T1, T2, and T3 located apart from each other are sequentially called one by one, and the work point T1 is called. , T2, T3 are captured in the captured image of the CCD camera 6, the captured XY coordinates of the work points T1, T2, and T3 are corrected from the captured coordinates in the captured image, and the corrected camera axis XY coordinates are calculated. The robot control unit 12 that is stored as points P1, P2, P3, positions the screw tightening unit 5 based on the corrected camera axis XY coordinates and drives the screw tightening unit 5, and after calculating the reference points of the three points or After the predetermined work is completed, the XY coordinates of the work points are sequentially called, and these are replaced with non-Cartesian coordinates consisting of a line connecting two adjacent work points T1, T2, and T3 corresponding to the reference points, and the three points are described. The control device 9 is provided with a coordinate conversion unit 29 that replaces the corrected non-Cartesian coordinates, which is a line segment connecting two adjacent points P1, P2, and P3 of the above, and the tilt of the work object W by the control device 9. The feature is that it is possible to correspond to. According to this configuration, when there are a large number of work points, the screw tightening unit 5 is operated while correcting the coordinates of the first three work points, and these three points are used as reference points, and after the predetermined work is completed, or When the coordinate correction of the work points is completed, the XY coordinates of the work points are sequentially called, and these are non-Cartesian coordinates consisting of a line connecting two adjacent work points of the three work points, the three points. It can be replaced with corrected non-Cartesian coordinates consisting of a line segment connected by two reference points adjacent to the reference point, and the correction of the XY coordinates of the fourth and subsequent work points can be sequentially corrected without wasting time. It can be carried out.

In addition, the robot with a swivel arm according to the embodiment of the present invention has two work points T1 that are located away from a base point such as the origin of XY coordinates among the work points stored in advance for the work object. , T2 XY coordinates are sequentially called one by one, the working points T1 and T2 are captured in the captured image of the CCD camera 6, and the captured XY coordinates of the working points T1 and T2 are corrected from the captured coordinates in the captured image. A robot that calculates as the corrected camera axis XY coordinates, stores them as reference points P1 and P2, positions the screw tightening unit 5 based on the corrected camera axis XY coordinates, and drives the screw tightening unit 5. After calculating the reference points of the two points or completing the predetermined work, the control unit 12 sequentially calls the XY coordinates of the work points, and this is a non-line segment connecting the work points T1 and T2 corresponding to the reference points and the base point. The control device 9 is provided with a coordinate conversion unit 29 that replaces the coordinates with orthogonal coordinates and replaces the two reference points P1 and P2 with corrected non-orthogonal coordinates consisting of a line segment connecting the base points. It may be configured to be able to cope with the inclination of an object. In this case, since the corrected non-orthogonal coordinates can be constructed by the line segment connecting the two reference points P1 and P2 and the base point, the corrected non-orthogonal coordinates can be replaced from the third and subsequent points, and the XY coordinate conversion can be performed accordingly. The time required for this can be shortened.

The coordinate conversion unit 29 according to the embodiment of the present invention calculates the distribution ratio of each line segment by setting the coordinate points on each coordinate axis of the non-Cartesian coordinates as the distribution points Pzna and Pznb of each line segment, and also calculates the distribution ratio of each line segment from the distribution ratio after correction. The coordinates of the corrected distribution points Pzfna and Pzfnb of the coordinate axes of the orthogonal coordinates may be calculated, and the corrected XY coordinates of the working point may be calculated from the coordinates of the corrected distribution points Pzfna and Pzfnb. In this case, the work points after the fourth point can be easily replaced with the corrected non-orthogonal coordinates consisting of three reference points (the same applies to the case of two reference points).

Although the screw tightening robot 1 with a swivel arm is described in the present embodiment, it may be a robot for caulking parts (not shown) or a robot for mounting parts (not shown). , The same effect can be obtained. Further, the specific configuration of each part of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

1 ... Screw tightening robot with swivel arm,
2 ... base,
3 ... Single-axis robot,
4 ... Swivel arm,
5 ... Screw tightening unit,
6 ... CCD camera,
7 ... θ-axis motor,
9 ... Control device,
12 ... Robot control unit,
16 ... Memory
17 ... Image processing unit,
18 ... Screw tightening unit control unit,

W ... Work object

Claims (9)

A swivel arm equipped with a work unit is attached to the single-axis robot, the origin axis of the polar coordinates of the swivel arm is positioned on the axial coordinates of the single-axis robot, and the single-axis robot moves and swivels the work point of the work object. Stores the storage unit that stores the combined coordinates (Yyn, θn) consisting of the axial coordinates Yyn and the polar coordinates θn with the swivel arm swivel angle θn, and the swivel radius Rt to the work unit that swivels integrally with the swivel arm. The control device is provided with a storage unit for converting the combined coordinates (Yyn, θn) and a coordinate conversion unit for converting the combined coordinates (Yyn, θn) into the work axis XY coordinates (Xtn, Ytn) of the work unit. The control device provides the work axis XY coordinate data. A single-axis robot with a swivel arm, which controls the axial movement and the swivel movement based on (Xtn, Ytun). A storage unit that stores the work point of the work object as a composite coordinate (Yyn, θn) consisting of the axial coordinate Yyn when the single-axis robot moves and swivels, and the polar coordinate θn where the swivel angle of the swivel arm is θn. A storage unit that stores the swivel radius Rt to the work unit that swivels integrally with the swivel arm and the swivel radius Rc to the CCD camera for detecting the work point, and the work unit and the CCD camera with respect to the rotation center of the swivel arm. A storage unit that stores the attachment angle θtc between the two, a coordinate conversion unit that converts the combined coordinates (Yyn, θn) into working axis XY coordinates (Xtn, Ytun), and the working axis XY coordinates (Xtn, Ytn). The control device is equipped with a coordinate conversion unit that converts the coordinates to the combined camera axis coordinates (Yycn, θcn), and this control device makes it possible to move the CCD camera to the work point. robot. The control device uses one work axis XY coordinates (Xtn, Ytun) of the work point as an imaging origin on the imaging coordinates, and is captured by actually photographing the working point through the imaging origin and the CCD camera. It is further provided with an imaging correction unit that calculates the corrected work axis XY coordinates (Xtfn, Ytfn) of the work point from the difference from the imaged XY coordinates of the work point, and the axis movement and rotation are performed based on the corrected work axis XY coordinates. The single-axis robot with a swivel arm according to claim 1 or 2, wherein the movement is controlled. The imaging correction unit includes an image processing unit that calculates unprocessed correction coordinates (Cxmn, Cymn) from the imaging origin and the imaging coordinates of the working point in the captured image, and the inclination θn of the imaging coordinates with respect to the origin axis of the polar coordinates. And the unprocessed correction coordinates (Cxmn, Cymn), the correction coordinates of the XY coordinates are calculated and converted into the corrected camera axis XY coordinates (Xcfn, Ycfn), and this is converted into the corrected work axis XY coordinates (Xtfn, Ytfn). The single-axis robot with a swivel arm according to claim 3, further comprising such a configuration. The configuration according to any one of claims 1 to 4 is provided, and the axis coordinates Yyn, the composite coordinates (Yyn, θn) and the camera axis composite coordinates (Yyn, θcn) in the configuration are set to the axis coordinates Xxn and the composite coordinates (Xxn, respectively). A single-axis robot with a swivel arm, characterized in that it is provided with a configuration that replaces θn) and camera axis composite coordinates (Xxcn, θcn). Of the work points stored in advance for the work object, the XY coordinates of the three work points T1, T2, and T3 located apart from each other are sequentially called one by one, and the work points T1, T2, and T3 are CCD. It is captured in the captured image of the camera, the captured XY coordinates of the working points T1, T2, and T3 are corrected from the captured coordinates in the captured image and calculated as the corrected camera axis XY coordinates, and these are used as the reference points P1, P2, and P3. In addition to being stored, the robot control unit that positions the work unit based on the corrected camera axis XY coordinates and drives the work unit, and the XY of the work points in sequence after calculating the three reference points or completing the predetermined work. Call the coordinates and replace them with non-Cartesian coordinates consisting of a line connecting two adjacent work points T1, T2, T3 corresponding to the reference point, and adjacent the three reference points P1, P2, P3. The control device is equipped with a coordinate conversion unit that replaces the corrected non-Cartesian coordinates with a line segment connecting the two points, and the control device can handle the tilt of the work object. Axis robot. Of the work points stored in advance for the work object, the XY coordinates of the two work points T1 and T2 located away from the base point are sequentially called one by one, and the work points T1 and T2 are referred to by the CCD camera. It is captured in the captured image, the captured XY coordinates of the work points T1 and T2 are corrected from the captured coordinates in the captured image, calculated as the corrected camera axis XY coordinates, and these are stored as reference points P1 and P2, and are also stored. The robot control unit that positions the work unit based on the corrected camera axis XY coordinates and drives the work unit, and after calculating the two reference points or completing the predetermined work, sequentially call the XY coordinates of the work points and call them. It is replaced with non-orthogonal coordinates consisting of a line segment connecting the work points T1 and T2 corresponding to the reference point and the base point, and corrected non-orthogonal coordinates consisting of a line segment connecting the reference points P1 and P2 of the two points and the base point. A single-axis robot with a swivel arm, characterized in that the control device is provided with a coordinate conversion unit to be replaced, and the control device can respond to the inclination of the work object. The coordinate conversion unit calculates the distribution ratio of each line segment by using the coordinate points on each coordinate axis of the non-Cartesian coordinates as the distribution points of each line segment, and calculates the distribution point coordinates of the coordinate axes of the corrected non-Cartesian coordinates from the distribution ratio. The single-axis robot with a swivel arm according to claim 6 or 7, wherein the corrected XY coordinates of the work point are calculated from the distribution point coordinates. The working unit is a screw tightening unit, and is a screw tightening robot with a swivel arm, comprising the configuration according to any one of claims 1 to 8.

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