JP7458579B2 - A three-dimensional measuring machine and a measuring method using a three-dimensional measuring machine, - Google Patents

Description

The present invention relates to a three-dimensional measuring machine and a measuring method using the three-dimensional measuring machine, and particularly relates to a technique that can reduce variations in measurement accuracy among operators and prevent erroneous operations.

2. Description of the Related Art Coordinate measuring machines are known that manually measure objects to be measured using an operating member such as a joystick. For example, Patent Document 1 describes a three-dimensional measuring machine that measures a workpiece by moving a probe by operating a joystick.

Japanese Patent Application Laid-Open No. 7-113628

When probing an inclined measurement surface (hereafter also referred to as an inclined surface) of an object to be measured, it is necessary to move the probe diagonally by moving multiple axes simultaneously (hereafter also referred to as diagonal movement).

However, when operating the joystick on the operation panel, there are cases where the object deviates from the normal direction or where a constant speed cannot be maintained. In such a case, it becomes a cause of variation in measurement accuracy. Further, diagonal movement requires some getting used to, and there is a risk that an inexperienced operator may accidentally collide the probe with the probe.

The present invention has been made in view of these circumstances, and is a three-dimensional probe that enables probing from the normal direction to an inclined surface at a constant speed, reduces variations in measurement accuracy, and prevents erroneous operation. The purpose is to provide a measuring machine and a measuring method using a three-dimensional measuring machine.

The three-dimensional measuring machine of the first aspect is a three-dimensional measuring machine whose position and orientation are freely displaceable and which measures a plurality of measuring elements formed on an object to be measured by a probe. a normal vector calculation unit that calculates a line vector; a condition determination unit that determines the azimuth angle θ and elevation angle φ of the probe to be brought into contact with the inclined surface and the moving speed of the probe based on the calculation results of the normal vector calculation unit; a component speed calculation unit that calculates an X component speed, a Y component speed, and a Z component speed of the movement speed based on the azimuth angle θ, the elevation angle φ, and the movement speed determined by the condition determination unit; The probe includes a signal generation section that generates a drive signal for driving the probe based on the velocity and the Z component velocity, and an operation section that inputs the drive signal to the drive section of the probe.

In the coordinate measuring machine of the second aspect, the normal vector calculation unit includes measuring the coordinates of at least three points on the inclined surface with a probe and calculating the normal vector from the coordinates of the three points.

In the coordinate measuring machine according to the third aspect, the normal vector calculation unit calculates the measurement moving speed based on the measurement azimuth θ, the measurement elevation angle φ, and the measurement movement speed input from the input unit. Calculate the measurement X component speed, measurement Y component speed, and measurement Z component speed, and generate a measurement drive signal based on the measurement X component speed, measurement Y component speed, and measurement Z component speed. This includes driving the probe with the 3D coordinates and measuring the coordinates of the three points.

In the coordinate measuring machine according to the fourth aspect, the condition determining unit inputs, from the input unit, the azimuth angle θ and the elevation angle φ of the probe to be brought into contact with the inclined surface based on the calculation result of the normal vector calculation unit, and the moving speed of the probe. This includes inputting information and making a decision.

In the coordinate measuring machine of the fifth aspect, the operation section is a switch that turns on and off.

A measuring method of a coordinate measuring machine according to a sixth aspect is a measuring method of a coordinate measuring machine that measures a plurality of measuring elements formed on a workpiece with a probe whose position and orientation are freely displaceable. A normal vector calculation step for calculating the normal vector of the slope including the normal vector calculation step, and determining the azimuth angle θ and elevation angle φ of the probe to be brought into contact with the slope surface, and the moving speed of the probe based on the calculation results of the normal vector calculation step. a component speed calculation step of calculating an X component speed, a Y component speed, and a Z component speed of the moving speed based on the azimuth angle θ, the elevation angle φ, and the moving speed determined in the condition determining step; The method includes a signal generation step of generating a drive signal for driving the probe based on the X-component speed, Y-component speed, and Z-component speed, and an operation step of inputting the drive signal to the drive section of the probe.

In the measuring method using a coordinate measuring machine according to the seventh aspect, the normal vector detection step includes measuring the coordinates of at least three points on the inclined surface using a probe, and calculating the normal vector from the coordinates of the three points.

According to the present invention, probing can be performed at a constant speed from the normal direction to an inclined surface, and variations in measurement accuracy can be reduced, and erroneous operations can be prevented.

FIG. 1 is an external perspective view of the coordinate measuring machine. FIG. 2 is an enlarged view of the probe head showing rotational movement of the probe head around a first rotation axis. FIG. 3 is an enlarged view of the probe head showing the rotational movement of the probe head around the second rotation axis. FIG. 4 is a functional block diagram of the computer. FIG. 5 is a conceptual diagram showing an example of a workpiece. FIG. 6 is a flowchart showing the flow of measurement processing by the three-dimensional measuring machine. FIG. 7 is a flowchart showing the flow of the slope surface processing in step S4 in FIG. FIG. 8 is a diagram for explaining the process of calculating a normal vector. FIG. 9 is a diagram for explaining the process of calculating a normal vector. FIG. 10 is a diagram for explaining the process of calculating a normal vector. FIG. 11 is a diagram for explaining the process of calculating a normal vector. FIG. 12 is a diagram for explaining the process of determining the direction of a normal vector. FIG. 13 is a diagram for explaining the process of determining the direction of a normal vector. FIG. 14 is a diagram for explaining the process of calculating the azimuth angle θ and the elevation angle φ. FIG. 15 is a diagram for explaining an example of a screen displayed on the display unit.

[Overall configuration of three-dimensional measuring machine]
FIG. 1 is an external perspective view of a coordinate measuring machine (CMM) 10. As shown in FIG. The three-dimensional measuring machine 10 displaces the position and orientation of the probe 24A while measuring the coordinate values (coordinate values in the X-axis direction, coordinate values in the Y-axis direction, and It is a measuring machine that measures coordinate values in the Z-axis direction, and is also called a coordinate measuring machine or a three-dimensional coordinate measuring machine. Note that the X-axis, Y-axis, and Z-axis in FIG. 1 are a mechanical coordinate system that is a coordinate system determined based on a mechanical coordinate origin specific to the three-dimensional measuring machine 10.

As shown in FIG. 1, the coordinate measuring machine 10 includes a pedestal 12, a table 14 (surface plate) provided on the pedestal 12, a right Y carriage 16R and a left Y carriage 16R erected at both ends of the table 14. It includes a carriage 16L and an X guide 18 that connects the upper parts of the right Y carriage 16R and the left Y carriage 16L. A gate-shaped frame 26 is constituted by the right Y-carriage 16R, the left Y-carriage 16L, and the X guide 18.

Sliding surfaces on which the right Y-carriage 16R and the left Y-carriage 16L slide along the Y-axis direction are formed on the top and side surfaces of both ends of the table 14. Furthermore, air bearings (not shown) are provided on the right Y-carriage 16R and the left Y-carriage 16L at positions facing the sliding surface of the table 14. Thereby, the right Y-carriage 16R and the left Y-carriage 16L are movable in the Y-axis direction together with the X guide 18.

The X-carriage 20 is attached to the X-guide 18. A sliding surface along the X-axis direction is formed on this X-guide 18, along which the X-carriage 20 slides. In addition, an air bearing (not shown) is provided on the X-carriage 20 at a position opposite the sliding surface of the X-guide 18. This allows the X-carriage 20 to move freely in the X-axis direction.

A Z carriage (also referred to as a Z spindle) 22 is attached to the X carriage 20. Further, the X carriage 20 is provided with an air bearing (not shown) for guiding the Z carriage 22 in the Z axis direction. Thereby, the Z carriage 22 is held movably in the Z-axis direction by the X carriage 20.

A probe head 24 is attached to the lower end of the Z carriage 22. The probe head 24 is, for example, a five-axis simultaneous control probe head equipped with a stepless positioning mechanism.

FIG. 2 is an enlarged view of the probe head 24 showing the rotational movement of the probe head 24 around the first rotation axis A. The probe 24A can be moved steplessly with respect to the first rotation axis A within a range of minus θ from the vertical angle and a range of plus θ from the vertical angle. The probe 24A includes a stylus 24B and a contact 24C.

For example, if the lowest point of the contactor 24C is the 0 degree position of the probe 24A, the probe head 24 will move in a range of -115 degrees or more and plus 115 degrees or less about the first rotation axis A. Rotational movement is possible.

FIG. 3 is an enlarged view of the probe head 24 showing the rotational movement of the probe head 24 around the second rotation axis B. As shown in FIG.

The probe 24A can be moved steplessly with respect to the second rotation axis B in a range of minus φ from the horizontal angle and a range of plus φ from the horizontal angle. For example, the probe head 24 can rotate around the second rotation axis B within a range of -180 degrees or more and plus 180 degrees or less.

The probe head 24 is provided with a first drive section 35 (see FIG. 4) such as a motor that rotates the probe 24A around two axes, a first rotation axis A and a second rotation axis B, which are orthogonal to each other. As a result, the rotation angle θ around the first rotation axis A of the probe 24A and the rotation angle φ around the second rotation axis B of the probe 24A can be adjusted steplessly, and as a result, The attitude of the probe 24A (stylus 24B) can be arbitrarily displaced (rotated).

Returning to FIG. 1, although not shown, the three-dimensional measuring machine 10 includes a Y-axis drive unit that moves the portal frame 26 in the Y-axis direction, and an X-axis drive unit that moves the X-carriage 20 in the X-axis direction. and a Z-axis drive unit that moves the Z-carriage 22 in the Z-axis direction. Thereby, the probe head 24 and the probe 24A can be moved in three axial directions (XYZ directions) that are orthogonal to each other. The position and posture of the probe 24A can be freely displaced by the first drive section 35 and the second drive section 36, and the probe 24A can be arbitrarily displaced (moved and rotated). The first drive section 35 and/or the second drive section 36 may be referred to as a drive section.

A linear scale (not shown) for detecting a position in the Y-axis direction is provided at the end of the table 14 on the right Y-carriage 16R side. Further, the X guide 18 is provided with a linear scale (not shown) for detecting a position in the X-axis direction, and the Z carriage 22 is provided with a linear scale (not shown) for detecting a position in the Z-axis direction.

On the other hand, the right Y-carriage 16R is provided with a Y-axis position detection head (not shown) that reads the Y-axis position detection linear scale. The X-carriage 20 also includes an X-axis position detection head (not shown) and a Z-axis position detection head (not shown) that read the X-axis position detection linear scale and the Z-axis position detection linear scale, respectively. ) is provided. Furthermore, the probe head 24 is provided with a rotation angle detection section (not shown) such as a rotary encoder that detects the rotation angles θ and φ of the probe 24A. Based on the detection results of the XYZ axis direction detection head and the detection results of the rotation angle detection unit, the XYZ axis direction of the measurement position when the probe 24A (contactor 24C at the tip of the stylus 24B) contacts the measurement position of the workpiece W is determined. The coordinate values of can be detected.

The coordinate measuring machine 10 includes a drive controller 28 that controls the first drive section 35 and the second drive section 36 to control the movement of the probe head 24, that is, the displacement of the position and attitude of the probe 24A (stylus 24B). We are prepared. Here, the coordinate measuring machine 10 has an automatic measurement mode in which measurements are performed automatically, and a manual measurement mode in which measurements are performed manually. Therefore, in the automatic measurement mode, the drive controller 28 controls the first drive section 35 and the second drive section 36 under the control of the computer 32, which will be described later, to displace the position and orientation of the probe 24A.

Further, the drive controller 28 is provided with an operation section 28A such as a joystick for manually controlling the position and orientation of the probe 24A (stylus 24B). Therefore, in the manual measurement mode, the drive controller 28 displaces the position and orientation of the probe 24A by controlling the first drive section 35 and the second drive section 36 in response to the operation input to the operation section 28A.

The drive controller 28 is connected to a contact detection sensor (not shown) of the probe 24A, an XYZ axis direction detection head, and a rotation angle detection unit. The drive controller 28 acquires the detection results of the XYZ axis direction detection head and the rotation angle detection unit at the moment when the contact detection sensor detects that the probe 24A (contactor 24C) has come into contact with the measurement position of the workpiece W, and detects the coordinate values of the measurement position in the XYZ axis direction. The coordinate values of the measurement position in the XYZ axis direction are output from the drive controller 28 to the computer 32.

The computer 32 is connected to the drive controller 28 through various communication interfaces 30 such as a LAN (Local Area Network) so as to be capable of data communication. This computer 32 functions together with the aforementioned drive controller 28 as a measurement control device for the three-dimensional measuring machine of the present invention.

A program 32A corresponding to the measurement program of the present invention is installed in the computer 32. The computer 32 executes various controls of the three-dimensional measuring machine 10 by executing the program 32A.

The display unit 38 is connected to the computer 32. The computer 32 causes the display unit 38 to display various information on the three-dimensional measuring machine 10, the measurement position by the probe 24A, operation instructions, an input screen, and the like.

[Computer configuration]
FIG. 4 is a functional block diagram of the computer 32. As shown in FIG. 4, a control unit 40 comprised of a CPU (Central Processing Unit), memory, etc. of the computer 32 executes a program 32A. As a result, the control section 40 includes a storage section 41, a display control section 42, an input control section 43, a normal vector calculation section 46, a condition determination section 47, a component velocity calculation section 48, a signal generation section 49, a workpiece coordinate system It functions as a setting section 50, a workpiece coordinate system measurement section 51, and a measurement element measurement section 52.

In addition to the program 32A, the memory unit 41 stores various information related to the measurement of the workpiece W (not shown) by the coordinate measuring machine 10.

The display control unit 42 controls the display on the display unit 38. The input control section 43 controls the input section 44 . The input control section 43 receives input information into the control section 40 . Note that the input unit 44 is, for example, a keyboard, but may also be a touch panel that serves as both the display unit 38 and the input unit 44. Note that various functions will be described later.

[Object to be measured (work W)]
An example of a workpiece W, which is an object to be measured by the three-dimensional measuring machine 10, will be explained with reference to FIG. The workpiece W is a polyhedron having a surface to be measured, and the workpiece W is placed on a table 14 or the like. The workpiece W has, for example, a Z plane 62, two opposing Y planes 64 and 66, two opposing X planes 68 and 70, and a Z plane 62 and an 68. Note that if the X plane, Y plane, Z plane, and inclined plane are not particularly distinguished, they may be referred to as measurement planes. The measurement surface of the workpiece W includes a plurality of measurement elements (not shown). Here, the measurement element is a hole (circular hole), a convex portion, a groove, or the like formed in the workpiece W, and the workpiece W includes a plurality of measurement elements. Note that the measurement element may include the outer shape of the workpiece W.

Here, the inclined surface 72 can be defined as a surface of the workpiece W that is neither parallel nor perpendicular to the table 14 on which it is placed.

[Measurement method using a coordinate measuring machine]
Next, a measurement method (measurement processing) using the coordinate measuring machine 10 having the above configuration will be explained. FIG. 6 is a flowchart showing the flow of the measurement process for the workpiece W. FIG. 7 is a flowchart showing the flow of the slope processing in step S4 in FIG.

As shown in FIG. 6, first, the operator places the workpiece W to be measured on the table 14 of the coordinate measuring machine 10 (step S1).

Next, the workpiece coordinate system of the workpiece W placed on the table 14 is set (step S2). For example, the workpiece coordinate system setting unit 50 automatically operates the probe 24A to preliminarily measure the workpiece W. The measurement results are acquired by the workpiece coordinate system measuring section 51, and the workpiece coordinate system setting section 50 can set the workpiece coordinate system.

The operator operates the probe 24A using a joystick or the like on the operation unit 28A, and manually performs preliminary measurement of the workpiece W using the probe 24A. The measurement results are acquired by the workpiece coordinate system measurement unit 51, and the workpiece coordinate system setting unit 50 can set the workpiece coordinate system.

The workpiece coordinate system set by the workpiece coordinate system setting section 50 is stored in the storage section 41.

As described above, the probe 24A is driven by the first drive unit 35 and the second drive unit 36. Once the work coordinate system is set for the workpiece W, the operator measures the measurement elements included in the measurement surface of the workpiece W.

When the measurement is started, it is determined whether the measurement surface of the workpiece W is the inclined surface 72 (step S3). In step S3, if it is determined that the surface is not the inclined surface 72, the determination is No. If the determination is No, the process advances to step S5. On the other hand, if it is determined that it is the inclined surface 72, the determination is Yes. If the determination is Yes, the process advances to step S4.

A case where the determination is No and the process proceeds to step S5 will be described. In step S5, the measured measurement results are input to the measurement element measuring section 52. The measurement element measurement section 52 measures the workpiece W by executing a program stored in the storage section 41 or the like.

For example, the operator operates the joystick of the operation unit 28A to manually move the probe 24A and bring the probe 24A into contact with one of the measurement surfaces of the workpiece W. When the measurement surface of the workpiece W is a surface that is parallel or perpendicular to the table 14, such as the Z surface 62, the Y surfaces 64 and 66, and the X surfaces 68 and 70, the operator can relatively easily bring the probe 24A into contact with the measurement surface from the normal direction. When the measurement of the measurement surface of the workpiece W is finished, it is determined whether the measurement of the workpiece W is complete (step S6).

If it is determined that the measurement of the workpiece W has not been completed, the determination is No. If the determination is No, the process returns to step S3 to determine whether the surface is an inclined surface.

If the determination is Yes in step S3, as shown in FIG. 7, inclined surface processing is started for bringing the probe 24A into contact with the inclined surface from the normal direction (step S4).

First, the normal vector of the inclined surface 72 is calculated (step S4A). In step S4A, the normal vector calculation unit 46 calculates the normal vector of the inclined surface 72 including at least one measurement element.

An example of a method for calculating a normal vector will be described with reference to Fig. 8 to Fig. 13. In order to calculate a normal vector, it is necessary to identify the plane of the inclined surface 72. Then, as shown in Fig. 8, for example, the probe 24A is manually brought into contact with three points ( _P0 , _P1 , _P2 ) of the inclined surface 72 from the direction indicated by the arrows. The coordinates of the three points are acquired from the probe 24A by the measurement element measuring unit 52.

FIG. 9 conceptually shows the three points (P ₀ , P ₁ , P ₂ ) and the inclined surface 72 measured in FIG. 8 in the workpiece coordinate system. In the embodiment, the normal vector calculation unit 46 calculates the normal vector n of the inclined surface 72 based on the coordinates of the three points probed by the operator. Once the normal vector n can be calculated, the azimuth angle θ and the elevation angle φ, which are necessary conditions for bringing the probe 24A into contact with the inclined surface 72 from the normal direction, can be determined, as will be described later.

The normal vector calculation unit 46 can automatically calculate the normal vector n based on the coordinates of the three probed points.

As shown in FIG. 10, P ₀ = (x ₀ , y ₀ , z ₀ ), P ₁ = (x ₁ , y ₁ , z ₁ ), and P ₂ = (x ₂ , y ₂ , z ₂ ). Then, the vector P ₀ P ₁ = (x ₁ - x ₀ , y ₁ - y ₀ , z ₁ - z ₀ ), and the vector P ₀ P ₂ = (x ₂ - x ₀ , y ₂ -y ₀ , z ₂ -z ₀ ) is calculated.

The normal vector n can be calculated using the following formula.

However, when calculating the vector P ₀ P ₂ ×vector P ₀ P ₁ , there is a concern that a normal vector -n in the opposite direction may be calculated, as shown in FIG. Therefore, a function is required to determine which of normal vector n and normal vector -n is correct.

Next, the calculation process of the direction of the normal vector will be described. Fig. 12 is a diagram of the inclined surface 72 viewed from the side. As shown in Fig. 12, before probing, and the coordinates of the current value of the probe 24A are sampled at regular time intervals. For example, _S0 = ( _xs0 , _ys0 , _zs0 ) and _S1 = ( _xs1 , _ys1 , _zs1 ) are sampled. A vector _S1P0 is created from _P0 probed by the probe _24A and the immediately preceding sampling point _S1 .

As shown in FIG. 13, the angle α ₀ between the vector S ₁ P ₀ and the normal vector n is determined. Similarly, the angle α ₁ between the vector S ₁ P ₀ and the normal vector -n is determined.

When the normal vector n=(n ₀ , n ₁ , n ₂ ) and the vector S ₁ P ₀ =(a ₀ , a ₁ , a ₂ ), α ₀ can be calculated by the following formula.

α ₁ can also be calculated in the same way.

Among the calculated α ₀ and α _{1 ,} values less than 180° can be used in the following judgment formula.
If 0°≦α ₀ <90° and 90°≦α ₁ ≦180°, the normal vector n is adopted, whereas if 90°≦α ₀ <180° and 0°≦α ₁ ≦90°, the normal vector −n is adopted.

As described above, the normal vector calculation unit 46 calculates the normal vector n (or -n).

Next, probe conditions are determined based on the calculated normal vector (step S4B). In step S4B, the condition determination unit 47 determines the azimuth angle θ and elevation angle φ of the probe 24A to be brought into contact with the inclined surface 72, and the moving speed _Vxyz of the probe 24A based on the calculation result of the normal vector calculation step of step S4A. .

The normal vector n shown in equation 1 can be expressed as equation 3 below.

If the normal vector n is expressed as Equation 3, then what is the azimuth angle θ between the X axis and the line segment OQ (point Q is a point on the XY plane) and the elevation angle φ between the XY plane and the line segment OP, as shown in Figure 14? , can be expressed by the following trigonometric expression.

The condition determination unit 47 can automatically determine the azimuth angle θ and the elevation angle φ based on equation (1) and equation (2) using the program 32A stored in the storage unit 41 or the like. Further, the condition determining unit 47 can determine the moving speed V _xyz when the probe 24A contacts the inclined surface 72. _An appropriate moving speed V _xyz is determined based on the performance of the second drive unit 36 provided in the three-dimensional measuring machine 10, the type of measurement, the material of the workpiece W, and the like. The azimuth angle θ, the elevation angle φ, and the moving speed _Vxyz determined in step S4B are stored in the storage unit 41.

Next, component speeds of the moving speed are calculated based on the determined conditions (step S4C). In step S4C, the component speed calculation unit 48 calculates the X component speed V _x and the Y component speed _V of the movement speed V _y , and the Z component velocity _Vz are calculated. The moving speed V _xyz , the X component speed V _x , the Y component speed V _y , and the Z component speed V _z can be expressed by the following equations.
V _xyz = (V _x ² + V _y ² + V _z ² ) ^(1/2) ...(5)
V _x =V _xyz cosθcosφ...(6)
V _y =V _xyz sinθcosφ...(7)
V _z =V _xyz sinφ...(8)
By applying equations (1) to (4) calculated in step S4B to equations (6) to (8) expressed in step S4C, the X component speed V _x , the Y component speed V _y , and Z The component velocity _Vz can be calculated. The component speed calculation unit 48 automatically calculates each component speed of the moving speed using the program 32A stored in the storage unit 41 or the like.

Next, a drive signal is generated based on the component speed of the moving speed (step S4D). In step S4D, the signal generation unit 49 generates a drive signal for driving the probe 24A based on the X-component velocity V _x , Y-component velocity V _y , and Z-component velocity V _z calculated in step S4C.

The signal generation unit 49 uses the program 32A stored in the storage unit 41 to generate a signal based on the X component speed V _x , the Y component speed V _y , and the Z component speed V _z from the performance of the motor etc. of the second drive unit 36 . Then, a drive signal (for example, instruction voltage) to be input to the second drive unit 36 is automatically calculated. The calculated drive signal is stored in the storage section 41.

The above-described inclined surface processing is executed through the processing from step S4A to step S4D.

Next, returning to FIG. 6, after the inclined surface processing (step S4), the process proceeds to step S5) of measuring the workpiece W.

When measuring the inclined surface 72 that has been subjected to the inclined surface treatment, the operator does not need to manually operate the probe 24A using a joystick or the like of the operating section 28A. The operator can move the probe 24A to the inclined surface by, for example, turning on and off a switch (not shown) provided on the operating section 28A. For example, when an operator presses a switch, a drive signal is applied to the probe 24A to move it toward the inclined surface 72. The azimuth angle θ and the elevation angle φ of the probe 24A are adjusted so that they are parallel to the normal vector of the inclined surface 72. When the switch is released or probed, the movement of probe 24A is stopped. Since the operator can operate the probe 24A only by using a switch rather than by operating a stick on the operating section 28A, the probe 24A can be moved diagonally at a constant speed at a desired angle with fewer erroneous operations. When the operator presses the switch, for example, the azimuth angle θ, the elevation angle φ, and the drive signal stored in the storage unit 41 are input to the measurement element measurement unit 52, and the probe 24A is moved to the inclined surface via the drive controller 28. Move to 72.

After completing the measurement of the inclined surface of the workpiece W, it is determined whether or not the measurement of the workpiece W has been completed (step S6). If it is determined that the measurement of the workpiece W has not been completed, the determination is No. If the determination is No, the process returns to the determination of whether the surface is an inclined surface (step S3).

Steps S3 to S5 are repeated until the result at the completion of measurement (step S6) is Yes.

After the slope processing (step S4) is completed and before the measurement of the workpiece W (step S5), a screen 100 shown in FIG. 15 may be displayed on the display unit 38. The screen 100 includes an angle designation screen 110 related to the azimuth angle θ and elevation angle φ of the probe 24A, a speed designation screen 120 related to the moving speed V _xyz of the probe, and a movement direction display screen 130 showing the movement direction of the probe 24A. Contains. Before measuring the workpiece W, the calculated azimuth angle θ, elevation angle φ, and moving speed V _xyz can be confirmed.

Furthermore, the operator can input the azimuth angle θ, the elevation angle φ, and the moving speed V _xyz from the input unit 44 on the screen 100 . Since a drive signal can be generated by inputting the azimuth angle θ, the elevation angle φ, and the moving speed _Vxyz and executing steps S4C and S4D shown in FIG. 7, the probe 24A is moved under the input conditions, The probe 24A can be brought into contact with the workpiece W.

The operator can arbitrarily display the screen 100 shown in FIG. 15, input the azimuth angle θ, the elevation angle φ, and the moving speed _Vxyz from the input unit 44, and can bring the probe 24A into contact with the workpiece W under the input conditions. .

7, when determining the coordinates of three points on the inclined surface 72, the probe 24A can be brought into contact with the workpiece W by operating a switch instead of manually by an operator. The measurement azimuth angle θ, the measurement elevation angle φ, and the measurement movement velocity V _xyz can be input from the screen 100. By executing steps S4C and S4D shown in FIG 7, the measurement X-component velocity V _x , the measurement Y-component velocity V _y , and the measurement Z-component velocity V _z can be calculated, and a measurement drive signal can be generated.

If the azimuth angle θ for measurement and the elevation angle φ for measurement are set values such that the deviation from the azimuth angle θ and the elevation angle φ of the normal vector is less than ±90 degrees, the inclined surface 72 can be probed. The measurement azimuth angle θ and the measurement elevation angle φ do not require that the probe 24A be parallel to the normal vector of the inclined surface 72.

10 three-dimensional measuring machine, 12 stand, 14 table, 16L left Y carriage, 16R right Y carriage, 18 X guide, 20 X carriage, 22 Z carriage, 24 probe head, 24A probe, 24B stylus, 24C contactor, 26 gate mold frame, 28 drive controller, 28A operation section, 30 communication interface, 32 computer, 32A program, 35 first drive section, 36 second drive section, 38 display section, 40 control section, 41 storage section, 42 display control section, 43 input control unit, 44 input unit, 46 normal vector calculation unit, 47 condition determination unit, 48 component velocity calculation unit, 49 signal generation unit, 50 workpiece coordinate system setting unit, 51 workpiece coordinate system measurement unit, 52 measurement element measurement part, 62 Z plane, 64 Y plane, 66 Y plane, 68 X plane, 70 X plane, 72 inclined plane, 100 screen, 110 angle specification screen, 120 speed specification screen, 130 movement direction display screen,

Claims (5)

In a three-dimensional measuring machine that can freely change its position and orientation and measures multiple measurement elements formed on an object to be measured using a probe,
a normal vector calculation unit that calculates a normal vector of an inclined surface including at least one of the measurement elements;
a condition determining unit that determines an azimuth angle θ and an elevation angle φ of the probe to be brought into contact with the inclined surface and a moving speed of the probe based on the calculation result of the normal vector calculating unit;
a component speed calculation unit that calculates an X component speed, a Y component speed, and a Z component speed of the movement speed based on the azimuth angle θ, the elevation angle φ, and the movement speed determined by the condition determination unit;
a signal generation unit that generates a drive signal for driving the probe based on the X-component velocity, the Y-component velocity, and the Z-component velocity;
an operation unit for inputting the drive signal to the drive unit of the probe;
Equipped with
The normal vector calculation unit includes:
normal vector calculation processing of measuring the coordinates of at least three points on the inclined surface with the probe and calculating the normal vector from the coordinates of the three points;
a sampling process of repeatedly sampling the coordinates of the tip of the probe before bringing the probe into contact with one of the three points;
The one point is P0 _, the coordinates sampled immediately before the one point in the sampling process are S1 _, the normal vector calculated in the normal vector calculation process is n, and the normal vector and is the angle formed by the vector S ₁ P ₀ and the normal vector n, and the angle formed by the vector S ₁ P ₀ and the normal vector -n, when the normal vector in the opposite direction is -n, a determination process that determines the direction of the normal vector based on;
execute,
CMM. The normal vector calculation unit includes:
Based on the measurement azimuth θ, the measurement elevation angle φ, and the measurement movement speed input from the input unit, the measurement X component speed, measurement Y component speed, and measurement Z component speed of the measurement movement speed are determined. The component velocity is calculated, and the probe is driven by a measurement drive signal generated based on the measurement X component velocity, the measurement Y component velocity, and the measurement Z component velocity, and the coordinates of the three points are determined. including measuring;
The coordinate measuring machine according to claim 1 . The condition determining unit includes:
determining an azimuth angle θ and an elevation angle φ of the probe to be brought into contact with the inclined surface based on calculation results of the normal vector calculation unit, and a moving speed of the probe by inputting them from an input unit;
The coordinate measuring machine according to claim 1 or 2 . The coordinate measuring machine according to claim 1 , wherein the operation unit is a switch that switches on and off . A measurement method for a coordinate measuring machine that measures a plurality of measurement elements formed on a measurement object by a probe whose position and attitude can be freely changed, comprising the steps of:
A normal vector calculation step of calculating a normal vector of an inclined surface including at least one of the measurement elements;
a condition determination step of determining an azimuth angle θ and an elevation angle φ of the probe to be brought into contact with the inclined surface and a moving speed of the probe based on a calculation result of the normal vector calculation step;
a component velocity calculation step of calculating an X component velocity, a Y component velocity, and a Z component velocity of the moving velocity based on the azimuth angle θ, the elevation angle φ, and the moving velocity determined in the condition determination step;
a signal generating step of generating a drive signal for driving the probe based on the X component velocity, the Y component velocity, and the Z component velocity;
an operating step of inputting the drive signal to a drive unit of the probe;
having
The normal vector calculation step includes:
a normal vector calculation process for measuring coordinates of at least three points on the inclined surface by the probe and calculating the normal vector from the coordinates of the three points;
a sampling process for repeatedly sampling coordinates of the tip of the probe before the probe is brought into contact with one of the three points;
a determination process for determining a direction of the normal vector based on an angle between vector S 1 P 0 and the normal vector _{n ,} and an angle between vector S 1 P 0 and the normal vector -n, where P 0 is the one point, S 1 is the coordinate sampled immediately before the one point in the sampling process, n is the normal vector _calculated in _{the normal} vector calculation _process , and -n is the normal vector in the opposite direction to the normal vector;
including,
Measurement methods using a coordinate measuring machine.

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