Industrial robot end drill parameter acquisition device and method

Abstract

The application discloses an industrial robot end drill bit parameter acquisition device, which comprises a sleeve, a reciprocating push rod mechanism and a target ball fixing mechanism. The industrial robot end drill bit parameter acquisition device can realize the switching of two use modes through the addition / removal of an expansion sleeve mechanism. In the use mode of adding the expansion sleeve mechanism, one end of the reciprocating push rod mechanism extends into one end of the sleeve, the end of the reciprocating push rod mechanism extending out of the sleeve is provided with the target ball fixing mechanism, and the expansion sleeve mechanism is arranged at the other end of the sleeve and cooperates with the sleeve to be used for mounting the drill bit. In the use mode of removing the expansion sleeve mechanism, one end of the reciprocating push rod mechanism extends into one end of the sleeve, the end of the reciprocating push rod mechanism extending out of the sleeve is provided with the target ball fixing mechanism, and the other end of the sleeve is used for the extension of the drill bit. The application can be used for realizing the acquisition of the drill bit pose parameters and the acquisition of the drill bit length parameters.

Description

TECHNICAL FIELD

[0001] The application relates to an industrial robot end drill parameter acquisition device and method, and belongs to the technical field of industrial robot automation. BACKGROUND

[0002] The robot end effector is a crucial component in robot technology, which directly affects the working accuracy, efficiency and reliability of the robot. Among the numerous end effectors, the end drill is widely used in the fields of automobile manufacturing, aerospace, precision machining, etc., and its calibration accuracy is of great significance to ensure product quality. With the continuous improvement of industrial automation level, the calibration technology of the robot end drill is facing many challenges.

[0003] The current difficulties in robot end drill calibration at home and abroad include high precision and repeatability requirements, mainly manifested in that the robot end drill has very high requirements for position accuracy and repeatability when performing drilling, tapping and other tasks.

[0004] The difficulty of multi-degree-of-freedom coordinated control is mainly manifested in that the robot end drill usually has multiple degrees of freedom, and how to accurately coordinate and control these degrees of freedom during calibration is a key problem in calibration technology.

[0005] The complexity and real-time performance of the calibration algorithm mainly manifest that the calibration algorithm of the robot end drill needs to consider nonlinearity, time-varying and other factors, which makes the algorithm design complex. The limitations of sensor technology mainly manifest that sensors are important tools for robot end drill calibration, but the current sensor technology has limitations in accuracy, stability, anti-interference ability, etc. Poor environmental adaptability mainly manifests that the robot end drill may face complex environmental factors such as temperature change, vibration and electromagnetic interference when working in industrial field. SUMMARY

[0006] The application provides an industrial robot end drill parameter acquisition device and method, which realizes the switching of two use modes by adding / removing the expansion sleeve mechanism. In the two use modes, on the one hand, it can be used to acquire the drill pose parameters; on the other hand, it can be used to acquire the drill length parameters.

[0007] The technical scheme of the application is:

[0008] According to the first aspect of the present application, an industrial robot end drill parameter acquisition device is provided, comprising a sleeve 30, a reciprocating push rod mechanism, a target ball fixing mechanism; the industrial robot end drill parameter acquisition device switches between two use modes through the addition / removal of an expansion sleeve mechanism, in the use mode of adding the expansion sleeve mechanism, one end of the reciprocating push rod mechanism extends into one end of the sleeve 30, the end of the reciprocating push rod mechanism extending out of the sleeve 30 is provided with the target ball fixing mechanism, and the expansion sleeve mechanism is installed at the other end of the sleeve 30 and cooperates with the sleeve 30 to install the drill; in the use mode of removing the expansion sleeve mechanism, one end of the reciprocating push rod mechanism extends into one end of the sleeve 30, the end of the reciprocating push rod mechanism extending out of the sleeve 30 is provided with the target ball fixing mechanism, and the other end of the sleeve 30 is used for the drill to extend into.

[0009] Further, the expansion sleeve mechanism comprises an expansion sleeve outer sleeve 4, an expansion sleeve inner sleeve 5, a first screw 3, and a second screw 6; the expansion sleeve inner sleeve 5 extends into the expansion sleeve outer sleeve 4 and is fastened through the first screw 3 and the second screw 6.

[0010] Further, the reciprocating push rod mechanism comprises a connecting rod 10, a push plate 11, and a moving buckle device 17, and the industrial robot end drill parameter acquisition device further comprises a grating ruler 25 installed on the inner side of the sleeve 30; one end of the push plate 11 is connected with one end of the connecting rod 10, the other end of the connecting rod 10 is provided with the target ball fixing mechanism; the other end of the push plate 11 is provided with an arc-shaped contact groove 20, and the moving buckle device 17 is installed on the connecting rod 10; the connecting rod 10 is movably arranged in the sleeve 30 along a first preset direction, and the arc-shaped contact groove 20 is in contact with the end of the drill through the movement of the connecting rod 10 along the first preset direction to read the information of the grating ruler 25.

[0011] Further, the moving buckle device 17 comprises a spring mounting portion 21, an extension rod 22, and a spring 23; a plurality of fixed buckle holes are arranged at intervals along a first preset direction on the sleeve 30; the spring mounting portion 21 is arranged on the connecting rod 10, and the spring mounting portion 21 is provided with grooves extending along a second preset direction on the two sides of the inner side of the sleeve 30 in opposite arrangement, one end of the spring 23 is connected with the grooves, the other end of the spring 23 is connected with one end of the extension rod 22, and the other end of the extension rod 22 is a free end; the extension rod 22 is movably arranged along the second preset direction through the extension and contraction movement of the spring 23; the extension rod 22 cooperates with the fixed buckle hole at the required position through the movement of the connecting rod 10 along the first preset direction.

[0012] Further, the industrial robot end drill parameter acquisition device further comprises:

[0013] A first guide structure 18 is arranged inside the sleeve 30 and extends along a first preset direction, and is used for guiding the movement of the telescopic rod 22 in the moving buckle device 17 along the first preset direction;

[0014] A second guide structure 19 is arranged inside the sleeve 30 and extends along a first preset direction, and is used for guiding the movement of the push plate 11 in the reciprocating push rod mechanism along the first preset direction.

[0015] Further, the target ball fixing mechanism comprises a mounting frame 14, a first target seat fixing position 1, a second target seat fixing position 7, a third target seat fixing position 8, and a fourth target seat fixing position 9; the first target seat fixing position 1, the second target seat fixing position 7, the third target seat fixing position 8, and the fourth target seat fixing position 9 are arranged in intervals on the mounting frame 14; and the second target seat fixing position 7 and the fourth target seat fixing position 9 are symmetrically arranged based on the axis direction of the sleeve 30.

[0016] According to the second aspect of the present application, an industrial robot end drill parameter acquisition method is provided, which is performed by using the industrial robot end drill parameter acquisition device according to any one of the above, and is used for drill pose acquisition. The acquisition steps are as follows:

[0017] Step one: fix the industrial robot end drill parameter acquisition device with an additional expansion sleeve mechanism on the industrial robot end drill 26, and install three target balls 24 on the target seat fixing positions; place the laser tracker 28 on one side of the industrial robot, turn on the industrial robot, and make it in a normal working state; make the laser tracker 28 face the target seat fixing positions in the target ball fixing mechanism, and make sure that there is no obstacle between the laser tracker 28 and the target seat fixing positions, and then turn on the laser tracker 28 for preheating;

[0018] Step two: when the robot is in a zero position state, use the laser tracker 28 to collect one point for each of the three target balls 24 installed on the target seat fixing positions by using SA software, that is, respectively acquire the target ball center coordinate positions P1, P2, and P3, and use the three points to fit a plane as a first plane on the SA software; it is known that in the design, the distance from the first side surface of the target ball fixing mechanism to the sleeve axis is D, the radius of the target ball is R, and the distance between the center point P of the mounting frame 14 and the arc-shaped contact groove 20 on the plane of the push plate 11 is H; then translate the first plane by a distance L to obtain a second plane, and the second plane coincides with the sleeve axis; wherein L = R - D;

[0019] Step three, based on the second plane, establish a measurement coordinate system; the establishment of the measurement coordinate system, specifically: with the mounting frame 14 center point P as the origin of the measurement coordinate system, sleeve axis as the Z axis direction of the measurement coordinate system, the positive direction of Z axis points to the expansion sleeve mechanism, the X axis direction is perpendicular to the second plane direction, the positive direction of X axis points to the first plane, Y axis direction is determined according to the right hand rule, that is, the measurement coordinate system O j -X j Y j Z j is established; according to the position of the drill bit 26 end in the measurement coordinate system, the transformation relationship in the drill bit coordinate system is obtained is composed of translation vector and rotation matrix ;

[0020] Step four, calibrate the transformation relationship of the end flange coordinate system O f -X f Y f Z f of the industrial robot is composed of translation vector and rotation matrix ;

[0021] Step five, according to and , the pose of the drill bit end is obtained

[0022] Further, the fixing position of the target ball fixing mechanism is an open and hollow cylindrical structure, and the inner end face of the closed end face parallel to the sleeve axis in the fixing position of the target ball fixing mechanism is taken as the first side face of the fixing position of the target ball fixing mechanism.

[0023] Further, the transformation relationship in the drill bit coordinate system is expressed as:

[0024]

[0025] In the formula, the translation vector P0=[Px Py Pz] T -[L 0 0] T +[0 0 H] T , P0 represents the position of the drill bit 26 end in the measurement coordinate system, [Px Py Pz] represents the coordinates of P2 in the first plane; P=[Px Py Pz] T -[L 0 0] T represents the position of the mounting frame 14 center point P in the measurement coordinate system.

[0026] Further, the step four is specifically: first, drive the industrial robot 29 to a zero position state, rotate the fifth joint of the industrial robot 29, and collect the position coordinates of the point positions at intervals of 2°, then fit the above measurement points into a circle in the SA software, and take the normal vector of the circle as the five-axis axis, that is, the Z-axis direction of the coordinate system of the industrial robot 29; similarly, again adjust the industrial robot 29 to the zero position state, rotate the sixth joint of the industrial robot 29 alone, and collect the position coordinates of the point positions at intervals of 2°, to obtain the six-axis axis of the industrial robot 29; then, the common perpendicular of the five-axis axis and the six-axis axis is obtained through the SA software, that is, the X-axis of the coordinate system of the industrial robot end flange 27; next, the cross product in the SA software can obtain the Y-axis direction of the coordinate system of the industrial robot end flange 27; finally, offset the robot six-axis length along the negative direction of the Z-axis of the robot end flange coordinate system to the origin of the coordinate system of the industrial robot end flange 27, so that the coordinate system of the industrial robot end flange 27 O f -X f Y f Z f , and the transformation relationship

[0027] The beneficial effects of the present application are:

[0028] First, the coincidence of the drill bit axis and the sleeve axis can be ensured to the maximum extent, and the drill bit pose acquisition accuracy can be improved; the main performance is that: through the reciprocating push rod mechanism, in the up and down movement process, it is moved on the second guide structure, ensuring the uniqueness of the trajectory; and fixed through the moving buckle device, the moving buckle device moves in the first guide structure, also ensuring the uniqueness of the trajectory; and the second guide structure and the first guide structure are distributed on the inner side of the sleeve in parallel, ensuring the fixity and uniqueness of the trajectory; more importantly, an expansion sleeve is installed at the top end of the sleeve, which can well clamp the drill bit and ensure the coaxiality of the drill bit and the inner sleeve of the expansion sleeve, thereby further ensuring the coincidence of the drill bit axis and the sleeve axis.

[0029] Second, for the problem of accurately fixing the reciprocating push rod mechanism, the moving buckle device is adopted, the sleeve and the drill bit are in a suitable position through the movement of the reciprocating push rod, at this time the telescopic rod in the moving buckle device is in an elongated state under the action of the spring force, that is, in the fixed clamping hole, and the position of the drill bit is fixed.

[0030] Third, the sleeve and the moving buckle device are adopted, so that the fixing and pose acquisition process of the drill bit is more simple and convenient, and the operation difficulty is reduced. The length data of the drill bit is directly read by the grating ruler, without complex calculation, and the measurement efficiency is improved.

[0031] Fourthly, the drill bit end pose can be directly obtained by the method, and the traditional multi-point-to-tip calibration is replaced to provide accurate position and pose information for industrial robot processing. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 It is a schematic diagram of the overall structure of the present application;

[0033] Figure 2 It is a sectional view of the expansion sleeve mechanism of the present application;

[0034] Figure 3 It is a three-dimensional view of the expansion sleeve mechanism of the present application;

[0035] Figure 4 It is a sectional view of the sleeve structure of the present application;

[0036] Figure 5 It is a three-dimensional view of the sleeve structure of the present application;

[0037] Figure 6 It is a schematic diagram of the reciprocating push rod mechanism of the present application;

[0038] Figure 7 It is a sectional view of the sleeve and reciprocating push rod mechanism cooperation structure of the present application;

[0039] Figure 8 It is a sectional view of the moving buckle device structure of the present application;

[0040] Figure 9 It is a flow chart of the drill bit end pose method of the present application;

[0041] Figure 10 It is a schematic diagram of the coordinate system in the drill bit end pose method of the present application;

[0042] Figure 11 It is a schematic diagram of the industrial robot end drill bit pose calibration system of the present application;

[0043] The various reference numbers in the figure are: 1-first fixed target seat position, 2-tightening screw, 3-first screw, 4-expansion sleeve outer sleeve, 5-expansion sleeve inner sleeve, 6-second screw, 7-second fixed target seat position, 8-third fixed target seat position, 9-fourth fixed target seat position, 10-connecting rod, 11-push plate, 12-first fixed clamping hole, 13-second fixed clamping hole, 14-mounting frame, 15-third fixed clamping hole, 16-fourth fixed clamping hole, 17-moving buckle device, 18-first guide structure, 19-second guide structure, 20-arc-shaped contact groove, 21-spring mounting portion, 22- telescopic rod, 23-spring, 24-target ball, 25-grating ruler, 26-drill bit, 27-robot end flange, 28-laser tracker, 29-industrial robot, 30-sleeve, 31-target ball center. DETAILED DESCRIPTION

[0044] To make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. It should be noted that, in the absence of conflict, the embodiments in this application and the features in the embodiments can be combined with each other in any way.

[0045] The present invention provides an industrial robot end drill parameter acquisition device that can use either an additional expansion sleeve mechanism or a removal expansion sleeve mechanism. An embodiment of the additional expansion sleeve mechanism is described below:

[0046] Example 1: Figure 1-11 As shown, according to a first aspect of an embodiment of the present invention, a device for obtaining parameters of an industrial robot end drill bit is provided, comprising a sleeve 30, a reciprocating push rod mechanism, and a target ball fixing mechanism; the device for obtaining parameters of an industrial robot end drill bit is additionally provided with an expansion sleeve mechanism. When the additional expansion sleeve mechanism is used, one end of the reciprocating push rod mechanism extends into one end of the sleeve 30, and the target ball fixing mechanism is installed at one end of the reciprocating push rod mechanism extending out of the sleeve 30, and the expansion sleeve mechanism is installed at the other end of the sleeve 30, and the two cooperate to install the drill bit.

[0047] Furthermore, the expansion mechanism includes an expansion outer sleeve 4, an expansion inner sleeve 5, a first screw 3, and a second screw 6; the expansion inner sleeve 5 extends into the expansion outer sleeve 4 and is fastened by the first screw 3 and the second screw 6.

[0048] Furthermore, the reciprocating push rod mechanism includes a connecting rod 10, a push plate 11, and a movable snap-fit ​​device 17, and the industrial robot end drill bit parameter acquisition device also includes a grating scale 25 installed on the inner side of the sleeve 30; one end of the push plate 11 is connected to one end of the connecting rod 10, and the other end of the connecting rod 10 is installed with a target ball fixing mechanism; the other end of the push plate 11 is provided with an arc-shaped contact groove 20, and the movable snap-fit ​​device 17 is installed on the connecting rod 10; the connecting rod 10 is movably arranged in a first preset direction in the sleeve 30, and the arc-shaped contact groove 20 is brought into contact with the end of the drill bit by the movement of the connecting rod 10 along the first preset direction to read the information of the grating scale 25.

[0049] Specifically, the additional expansion sleeve mechanism is used as follows:

[0050] In this way, the additional expansion sleeve mechanism, the expansion sleeve outer sleeve 4 and the sleeve 30 are in interference fit, and the expansion sleeve mechanism is re-tightened by the left and right tightening screws 2 after being installed on the sleeve. When the screws are tightened, the inner sleeve and the outer sleeve are elastically deformed and tightly attached to the surface of the drill bit and the sleeve, generating a large friction force, so that the inner sleeve expands outward and the outer sleeve expands inward, thereby achieving clamping and fixing of the drill bit.

[0051] Further, the mobile buckle device 17 comprises a spring mounting portion 21, an extension rod 22, and a spring 23; a plurality of fixed buckle holes are arranged at intervals in the sleeve 30 along a first preset direction; as shown in the example, Figure 7 As shown in the example, four fixed buckle holes are shown, i.e., the second fixed buckle hole 13, the third fixed buckle hole 15, the first fixed buckle hole 12, and the fourth fixed buckle hole 16 arranged in order from top to bottom; the spring mounting portion 21 is arranged on the connecting rod 10, and the spring mounting portion 21 is provided with grooves extending along a second preset direction on the two sides of the inner side of the sleeve 30 in opposite arrangement, one end of the spring 23 is connected with the grooves, the other end of the spring 23 is connected with one end of the extension rod 22, and the other end of the extension rod 22 is a free end; the extension rod 22 is movably arranged along the second preset direction by the extension and contraction movement of the spring 23; the extension rod 22 is matched with the fixed buckle hole at the required position by the movement of the connecting rod 10 along the first preset direction; the first preset direction is perpendicular to the second preset direction.

[0052] Further, the industrial robot end drill bit parameter acquisition device further comprises:

[0053] A first guide structure 18 is arranged on the inner side of the sleeve 30 and extends along the first preset direction, and is used for guiding the movement of the extension rod 22 in the mobile buckle device 17 along the first preset direction;

[0054] A second guide structure 19 is arranged on the inner side of the sleeve 30 and extends along the first preset direction, and is used for guiding the movement of the push plate 11 in the reciprocating push rod mechanism along the first preset direction. In a specific application, the push plate 11 is provided with a protrusion, the protrusion is in sliding cooperation with the second guide structure 19, and the movement of the reciprocating push rod mechanism along the first preset direction is guided.

[0055] Further, the target ball fixing mechanism comprises a mounting frame 14, a first target seat fixing position 1, a second target seat fixing position 7, a third target seat fixing position 8, and a fourth target seat fixing position 9; the first target seat fixing position 1, the second target seat fixing position 7, the third target seat fixing position 8, and the fourth target seat fixing position 9 are arranged in intervals on the mounting frame 14; and the second target seat fixing position 7 and the fourth target seat fixing position 9 are symmetrically arranged based on the axis direction of the sleeve 30.

[0056] Illustratively, the mounting frame 14 is in a cross shape, and is used for mounting four target seat fixing positions, two of which are symmetrically arranged based on the axis direction of the sleeve, thereby achieving the acquisition of the position. The fixing position of the target ball fixing mechanism is a hollow cylindrical structure with an open upper end.

[0057] In a specific application, the industrial robot 29 and the laser tracker 28 can be used in cooperation; the industrial robot 29 is a six-degree-of-freedom robot, the drill bit 26 is mounted on the flange 27 at the end of the industrial robot, and the end drill bit pose acquisition device of the present application is mounted on the drill bit 26, and is used in the use mode described in the embodiment. In this use mode, after the sleeve 30 is fixed, two target balls 24 are mounted on the second target seat fixing position 7 and the fourth target seat fixing position 9, and one target ball 24 is selected and mounted on one of the first target seat fixing position 1 or the third target seat fixing position 8. Through the above-described mounting mode of the target ball 24, the sleeve 30 can be well centered. The cooperation of the laser tracker 28 and the target ball 24 can achieve the measurement of the six-degree-of-freedom end pose of the industrial robot 29. Specifically, the laser emitted by the laser tracker 28 is reflected on the corner cube prism of the target ball 24, and the three-dimensional position of the target ball 24 can be measured, and the position information can be obtained through the processing of the SA software.

[0058] According to the second aspect of the embodiment of the present application, an industrial robot end drill bit parameter acquisition method is provided, which is performed by using the industrial robot end drill bit parameter acquisition device described above, and is used for drill bit pose acquisition. The acquisition steps are as follows:

[0059] Step one: fix the industrial robot end drill bit parameter acquisition device of the additional sleeve mechanism on the industrial robot end drill bit 26, and mount three target balls 24 on the target seat fixing positions; place the laser tracker 28 on one side of the industrial robot, turn on the industrial robot, and make it in a normal working state; face the target seat fixing position in the target ball fixing mechanism with the laser tracker 28, and make sure that there is no obstacle between the laser tracker 28 and the target seat fixing position, and then turn on the laser tracker 28 for preheating;

[0060] Step two: when the robot is in a zero position state, use the laser tracker 28 to collect one point for each of the three target balls 24 mounted on the target seat fixing positions by using the SA software, that is, acquire the center coordinates of the target balls as P1, P2, and P3, as shown in Figure 7 As shown, these three points are used to fit a plane on the SA software as the first plane, which is Figure 10 Regarding planes P1 and P2 (which may also be understood as P1 and P3), it is known that when designing the present invention, the distance between the first side surface of the target ball fixing mechanism at the fixing position and the sleeve axis is D, the radius of the target ball is R, and the distance between the center point P of the mounting bracket 14 and the arcuate contact groove 20 on the plane of the push plate 11 is H. The first plane is then translated by a distance L, and the translated plane is used as the second plane, so that the second plane coincides with the sleeve axis. In the above description, the center point P of the mounting bracket 14 passes through the sleeve axis and is located in the second plane. The inner end surface of the closed end surface of the target ball fixing mechanism at the fixing position, which is parallel to the sleeve axis, is used as the first side surface of the target ball fixing mechanism at the fixing position; L=RD.

[0061] Step 3: Based on the second plane, establish a measurement coordinate system; the establishment of the measurement coordinate system is specifically as follows: the center point P of the mounting frame 14 is the origin of the measurement coordinate system, the axis of the sleeve is the Z-axis direction of the measurement coordinate system, the positive direction of the Z-axis points to the expansion sleeve mechanism, the X-axis direction is the direction perpendicular to the second plane, the positive direction of the X-axis points to the first plane, and the Y-axis direction is determined according to the right-hand rule, thus completing the measurement coordinate system O j -X j Y j Z j Then, the whole measurement coordinate system is translated H along the positive direction of the Z axis to obtain the drill coordinate system O tool -X tool Y tool Z tool ,like Figure 10 According to the position of the end of the drill bit 26 in the measurement coordinate system, the transformation relationship in the drill bit coordinate system is obtained is the translation vector and the rotation matrix Composition; Transformation relationship under the drill bit coordinate system The expression is:

[0062]

[0063] Where, It can be obtained from SA software, using three points to fit the plane, perform offset, and obtain the homogeneous transformation matrix of the drill end; translation vector P0=[Px Py Pz] T -[L 0 0]T+[0 0 H] T , P0 represents the position of the end of the drill bit 26 in the measurement coordinate system, [Px Py Pz] represents the coordinates of P2 in the first plane; P = [Px Py Pz] T -[L 0 0] Trepresents the position of the center point P of the mounting frame 14 in the measuring coordinate system;

[0064] Step four, calibrate the coordinate system O of the end flange of the industrial robot f -X f Y f Z f the transformation relationship is composed of a translation vector and a rotation matrix First, drive the industrial robot 29 to the zero position, slowly and smoothly rotate the fifth joint of the industrial robot 29, and collect the position coordinates of the points at intervals of 2° (the rotation range of the robot joint is at least 60°), and then fit the above measurement points into a circle in the SA software, and take the normal vector of the circle as the five-axis axis, that is, the Z-axis direction of the coordinate system of the industrial robot 29; Similarly, drive the industrial robot 29 to the zero position again, rotate the sixth joint alone, slowly and smoothly rotate the sixth joint of the industrial robot 29, and collect the position coordinates of the points at intervals of 2°, obtain the six-axis axis of the industrial robot 29; Then, the common perpendicular of the five-axis axis and the six-axis axis is obtained through the SA software, that is, the X-axis of the coordinate system of the end flange 27 of the industrial robot; Next, the cross product in the SA software can obtain the Y-axis direction of the coordinate system of the end flange 27 of the industrial robot; Finally, offset the robot six-axis length along the negative direction of the Z-axis of the robot end flange coordinate system to obtain the origin of the coordinate system O of the end flange 27 of the industrial robot, thereby obtaining the coordinate system O of the end flange 27 of the industrial robot f -X f Y f Z f , and the transformation relationship

[0065] Among them:

[0066]

[0067] Step five, according to and obtain the pose of the drill bit end is composed of a translation vector and a rotation matrix

[0068]

[0069] According to the industrial robot end drill parameter acquisition method and system of the above-mentioned embodiment of the present application, by using the designed sleeve 30, the target ball 24 and the laser tracker 28, the pose of the robot end drill 26 can be directly acquired, which replaces the traditional multi-point calibration method and can greatly improve the position accuracy and attitude accuracy of the industrial robot 29. The acquisition of the robot end position is more convenient and fast, and a feasible method is provided for the subsequent calibration research. As the application environment of the industrial robot end drill 26 pose acquisition method of the embodiment of the present application, as shown in Figure 11

[0070] The following describes an embodiment of removing the expansion sleeve mechanism:

[0071] Embodiment 2: According to the first aspect of the embodiment of the present application, as shown in Figure 1-11 , an industrial robot end drill parameter acquisition device is provided, which comprises a sleeve 30, a reciprocating push rod mechanism, and a target ball fixing mechanism. In the use mode of removing the expansion sleeve mechanism, one end of the reciprocating push rod mechanism extends into one end of the sleeve 30, the target ball fixing mechanism is installed at the end of the reciprocating push rod mechanism extending out of the sleeve 30, and the other end of the sleeve 30 is used for the drill to extend into.

[0072] Further, the reciprocating push rod mechanism comprises a connecting rod 10, a push plate 11 and a moving buckle device 17, and the industrial robot end drill parameter acquisition device further comprises a grating ruler 25 installed inside the sleeve 30. One end of the push plate 11 is connected to one end of the connecting rod 10, and the other end of the connecting rod 10 is installed with the target ball fixing mechanism. The other end of the push plate 11 is provided with an arc-shaped contact groove 20, and the connecting rod 10 is installed with the moving buckle device 17. The connecting rod 10 is movably arranged in the sleeve 30 along a first preset direction, and the arc-shaped contact groove 20 is in contact with the end of the drill by moving the connecting rod 10 along the first preset direction to read the information of the grating ruler 25.

[0073] Specifically, the use mode of removing the expansion sleeve mechanism is as follows:

[0074] In this mode, the expansion sleeve mechanism is removed, the sleeve 30 is completely sleeved on the drill 26, the upper end surface of the sleeve 30 is coincided with the tool end plane on which the drill 26 is installed, the reciprocating push rod device is moved to make the end of the drill 26 completely contact with the arc-shaped contact groove 20, and the reading of the grating ruler 25 is d3.

[0075] Further, the moving buckle device 17 comprises a spring mounting portion 21, an extension rod 22 and a spring 23. A plurality of fixed buckle holes are arranged at intervals on the sleeve 30 along the first preset direction. Exemplarily, as shown in Figure 7 ​As shown, four fixed clamping holes are shown, namely the second fixed clamping hole 13, the third fixed clamping hole 15, the first fixed clamping hole 12 and the fourth fixed clamping hole 16 arranged from top to bottom; the spring mounting portion 21 is arranged on the connecting rod 10, and the spring mounting portion 21 is arranged on the two opposite sides of the inner side of the sleeve 30 and provided with a groove extending in the second preset direction, one end of the spring 23 is connected with the groove, the other end of the spring 23 is connected with one end of the telescopic rod 22, and the other end of the telescopic rod 22 is a free end; the telescopic rod 22 is movably arranged along the second preset direction through the telescopic movement of the spring 23; through the movement of the connecting rod 10 along the first preset direction, the telescopic rod 22 is matched with the fixed clamping hole at the required position.

[0076] Further, the industrial robot end bit parameter acquisition device further comprises:

[0077] The first guide structure 18 is arranged on the inner side of the sleeve 30 and extends in the first preset direction, and is used for guiding the movement of the telescopic rod 22 in the movable clamping device 17 along the first preset direction;

[0078] The second guide structure 19 is arranged on the inner side of the sleeve 30 and extends in the first preset direction, and is used for guiding the movement of the push plate 11 in the reciprocating push rod mechanism along the first preset direction. In a specific application, the push plate 11 is provided with a protrusion, the protrusion is in sliding cooperation with the second guide structure 19, and the movement of the reciprocating push rod mechanism along the first preset direction is guided.

[0079] Further, the target ball fixing mechanism comprises a mounting frame 14, a first target seat fixing position 1, a second target seat fixing position 7, a third target seat fixing position 8 and a fourth target seat fixing position 9; the first target seat fixing position 1, the second target seat fixing position 7, the third target seat fixing position 8 and the fourth target seat fixing position 9 are arranged in a spaced manner on the mounting frame 14; the second target seat fixing position 7 and the fourth target seat fixing position 9 are symmetrically arranged based on the axis direction of the sleeve 30.

[0080] Exemplarily, the mounting frame 14 is in a cross shape, used for mounting four target seat fixing positions, two of which are symmetrically arranged based on the axis direction of the sleeve, thereby realizing the acquisition of the position. The fixing position of the target ball fixing mechanism is a hollow cylindrical structure with an open upper end.

[0081] Specific application, can cooperate with industrial robot 29, laser tracker 28 use; Industrial robot 29 is six degrees of freedom robot, drill bit 26 is installed on the flange 27 at the end of industrial robot, the end drill bit pose acquisition device of the application is installed on drill bit 26, carries out the use under the above two kinds of use mode.Under the first use mode, when the sleeve 30 is fixed, two target balls 24 are installed in the second target seat fixed position 7, fourth target seat fixed position 9, one target ball 24 is installed in one of the first target seat fixed position 1 or third target seat fixed position 8, the reasonable centering of sleeve 30 can be well realized through the above-described target ball 24 installation mode.Laser tracker 28 and target ball 24 cooperate to realize the measurement of six degrees of freedom of the end pose of industrial robot 29.Specifically, the laser emitted by laser tracker 28 is on the corner cube prism of target ball 24, and after reflection by the prism, the three-dimensional position of target ball 24 can be measured, and the position information can be obtained by processing through SA software.

[0082] According to the second aspect of the embodiment of the application, an industrial robot end drill bit parameter acquisition method is provided, which is carried out by using the industrial robot end drill bit parameter acquisition device described above, and is used for drill bit length parameter acquisition, specifically in that: in this mode, the expansion sleeve mechanism is removed, the sleeve 30 is completely sleeved on the drill bit 26, the upper end surface of the sleeve 30 is coincided with the tool end plane on which the drill bit 26 is installed, the reciprocating push rod device is moved, the end of the drill bit 26 is completely contacted with the arc-shaped contact groove 20, and the reading of the grating ruler 25 is read as d3.

[0083] The drill bit length is measured by the grating ruler, and the advantages of the industrial robot are as follows:

[0084] 1. The depth of the drilling hole can be controlled (to know the drilling depth, the length of the drill bit exposed should be greater than the machining depth).

[0085] 2. The exposed length is appropriate, which is beneficial to cooling and chip removal (the exposed length affects the position of the cooling liquid reaching the cutting edge and the discharge of the chips, and the appropriate exposed length is helpful for cooling and chip removal).

[0086] 3. The workpiece is prevented from being damaged: the appropriate exposed length can avoid the damage of the workpiece or the underlying workbench when the drill bit penetrates the bottom of the workpiece.

[0087] 4. The drill bit is prevented from being broken: if the exposed length is too short, the drill bit is easy to be broken due to excessive pressure; if the exposed length is too long, the drill bit may be broken due to imbalance at high speed.

[0088] The specific embodiments of the application are described in detail above with reference to the drawings, but the application is not limited to the above-described embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the application.

Claims

1. An industrial robot end-of-arm tool parameter acquisition device, characterized by, The industrial robot end drill parameter acquisition device includes a sleeve (30), a reciprocating push rod mechanism, and a target ball fixing mechanism. The industrial robot end drill parameter acquisition device can switch between two use modes by adding / removing the expansion sleeve mechanism. In the use mode of adding the expansion sleeve mechanism, one end of the reciprocating push rod mechanism extends into one end of the sleeve (30), and the other end of the reciprocating push rod mechanism extending out of the sleeve (30) is provided with the target ball fixing mechanism. The expansion sleeve mechanism is installed at the other end of the sleeve (30) and cooperates with the sleeve (30) to install the drill. In the use mode of removing the expansion sleeve mechanism, one end of the reciprocating push rod mechanism extends into one end of the sleeve (30), and the other end of the reciprocating push rod mechanism extending out of the sleeve (30) is provided with the target ball fixing mechanism. The other end of the sleeve (30) is used for the drill to extend into. The reciprocating push rod mechanism includes a connecting rod (10), a push plate (11), and a moving buckle device (17). The industrial robot end drill parameter acquisition device further includes a grating ruler (25) installed on the inside of the sleeve (30). One end of the push plate (11) is connected with one end of the connecting rod (10), and the other end of the connecting rod (10) is provided with the target ball fixing mechanism. The other end of the push plate (11) is provided with an arc-shaped contact groove (20). The moving buckle device (17) is installed on the connecting rod (10). The connecting rod (10) is movably arranged in the sleeve (30) along a first preset direction. The arc-shaped contact groove (20) is in contact with the end of the drill through the movement of the connecting rod (10) along the first preset direction, so as to read the information of the grating ruler (25). The moving buckle device (17) includes a spring mounting portion (21), a telescopic rod (22), and a spring (23). A plurality of fixed buckle holes are arranged at intervals on the sleeve (30) along the first preset direction. The spring mounting portion (21) is arranged on the connecting rod (10). The spring mounting portion (21) is provided with grooves extending along a second preset direction near the two sides of the inside of the sleeve (30) arranged oppositely. One end of the spring (23) is connected with the grooves, and the other end of the spring (23) is connected with one end of the telescopic rod (22). The other end of the telescopic rod (22) is a free end. The telescopic rod (22) is movably arranged along the second preset direction through the telescopic movement of the spring (23). The telescopic rod (22) cooperates with the fixed buckle hole at the required position through the movement of the connecting rod (10) along the first preset direction. The industrial robot end drill parameter acquisition device further includes: A first guide structure (18) is arranged on the inside of the sleeve (30) and extends along the first preset direction. The first guide structure (18) is used for guiding the movement of the telescopic rod (22) in the moving buckle device (17) along the first preset direction. A second guide structure (19) is arranged on the inside of the sleeve (30) and extends along the first preset direction. The second guide structure (19) is used for guiding the movement of the push plate (11) in the reciprocating push rod mechanism along the first preset direction.

2. The industrial robot end-of-arm tool parameter acquisition apparatus according to claim 1, characterized in that, The expansion sleeve mechanism comprises an expansion sleeve outer sleeve (4), an expansion sleeve inner sleeve (5), a first screw (3) and a second screw (6); the expansion sleeve inner sleeve (5) extends into the expansion sleeve outer sleeve (4) and is fastened by the first screw (3) and the second screw (6).

3. The industrial robot end-of-arm tool parameter acquisition apparatus of claim 1, wherein, The target ball fixing mechanism comprises a mounting frame (14), a first target seat fixing position (1), a second target seat fixing position (7), a third target seat fixing position (8) and a fourth target seat fixing position (9); the first target seat fixing position (1), the second target seat fixing position (7), the third target seat fixing position (8) and the fourth target seat fixing position (9) are arranged in intervals on the mounting frame (14); and the second target seat fixing position (7) and the fourth target seat fixing position (9) are symmetrically arranged based on the sleeve (30) axis direction.

4. An industrial robot end-of-arm tool parameter acquisition method, characterized by, The industrial robot end drill parameter acquisition device of any one of claims 1-3 is used for drill pose acquisition, and the acquisition steps are as follows: Step one, fix the industrial robot end drill parameter acquisition device with an additional expansion sleeve mechanism on the industrial robot end drill (26), and install three target balls (24) on the target seat fixing position; place the laser tracker (28) on one side of the industrial robot, turn on the industrial robot, and make it in a normal working state; make the laser tracker (28) face the target seat fixing position in the target ball fixing mechanism, and make sure that there is no obstacle between the laser tracker (28) and the target seat fixing position, and then turn on the laser tracker (28) for preheating; Step two, when the robot is in a zero position state, use the laser tracker (28) to collect one point for each of the three target balls (24) installed on the target seat fixing position by using SA software, that is, obtain the target ball center coordinate positions P1, P2 and P3, respectively, and fit a plane as a first plane by using the three points on the SA software; it is known that the distance from the first side surface of the target ball fixing mechanism fixing position to the sleeve axis is D, the radius of the target ball is R, and the distance between the center point P of the mounting frame (14) and the arc-shaped contact groove (20) on the plane of the push plate (11) is H; then translate the first plane by a distance L to obtain a second plane, and the second plane coincides with the sleeve axis; wherein L=R-D; Step three, based on the second plane, establish a measurement coordinate system; the establishment of the measurement coordinate system, specifically: with the mounting frame (14) center point P as the origin of the measurement coordinate system, sleeve axis as the Z axis direction of the measurement coordinate system, the positive direction of Z axis points to the expansion sleeve mechanism, the X axis direction is perpendicular to the second plane, the positive direction of X axis points to the first plane, Y axis direction is determined according to the right hand rule, that is, the measurement coordinate system O j -X j Y j Z j Establishment; according to the position of the drill bit (26) end in the measurement coordinate system, obtain the transformation relationship in the drill bit coordinate system is composed of translation vector and rotation matrix ; Step four, calibration of the end flange coordinate system O of the industrial robot f X f Y f Z f of the transformation relationship is composed of the translation vector and the rotation matrix ; Step five, according to and the pose of the drill tip is found 5. The industrial robot end-of-arm tool parameter acquisition method of claim 4, wherein, The fixing position of the target ball fixing mechanism is a hollow cylindrical structure with an open upper end, and the inner end face of the closed end face of the fixing position of the target ball fixing mechanism which is parallel to the sleeve axis is regarded as the first side surface of the fixing position of the target ball fixing mechanism.

6. The industrial robot end-of-arm tool parameter acquisition method of claim 4, wherein, The drill bit coordinate system under transformation relationship The expression is: where the translation vector P0= [Px Py Pz] T -[L 00] T +[00 H] T P0represents the position of the drill bit (26) tip in the measuring coordinate system, [Px Py Pz] represents the coordinates of P2in the first plane; P = [Px Py Pz] T -[L 00] T represents the position of the mounting bracket (14) center point P in the measuring coordinate system.

7. The industrial robot end-of-arm tool parameter acquisition method of claim 4, wherein, The fourth step is specifically: first, drive the industrial robot (29) to the zero position, rotate the fifth joint of the industrial robot (29), and collect the position coordinates of the point positions at intervals of 2°, then fit the measurement points into a circle in the SA software, and take the normal vector of the circle as the five-axis axis, that is, the Z-axis direction of the coordinate system of the industrial robot (29); similarly, again adjust the industrial robot (29) to the zero position, rotate the sixth joint of the industrial robot (29) alone, and collect the position coordinates of the point positions at intervals of 2°, obtain the six-axis axis of the industrial robot (29); then, find the common perpendicular of the five-axis axis and the six-axis axis through the SA software, that is, the X-axis of the coordinate system of the industrial robot end flange (27); then, cross-multiply in the SA software to obtain the Y-axis direction of the coordinate system of the industrial robot end flange (27); finally, offset the robot six-axis length downward along the negative direction of the Z-axis of the robot end flange coordinate system to obtain the origin of the coordinate system of the industrial robot end flange (27), thus the coordinate system of the industrial robot end flange (27) O f -X f Y f Z f , and the transformation relationship

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