JP7009751B2 - Measurement system, control device, measurement method - Google Patents

Description

The present invention relates to a measurement system including a measurement device for measuring a measurement target and a drive device for changing the relative positional relationship between the measurement device and the measurement target.

With the progress of ICT (Information and Communication Technology) in recent years, a system in which a control device and various measuring devices are integrated via a network or the like has been proposed even at a production site.

In the network used for such a system, each device including a control device and a measuring device has a timer synchronized with each other, and is determined based on the timing managed by the timer synchronized with each other. Guarantee periodic data communication. For example, Japanese Patent Application Laid-Open No. 2009-157913 (Patent Document 1) synchronizes time in a relatively short time without affecting control even between units provided with a timekeeping means having an ns-order timekeeping function. Disclose the configurations that can be made.

JP-A-2009-157913

The above-mentioned Japanese Patent Application Laid-Open No. 2009-157913 (Patent Document 1) discloses a technique for maintaining timer synchronization between devices connected to a network, but aggregates data acquired by each device and the like. No suggestions have been made regarding the processing of the system as a whole.

The present invention provides high-precision information indicating the shape of a measurement target even if the measurement device for the measurement target and the drive device that changes the relative positional relationship between the measurement device and the measurement target are not directly connected. One of the purposes is to provide a measurement system that can be generated.

A measuring system according to a certain aspect of the present invention includes a measuring device for measuring a measuring object and a driving device for changing the relative positional relationship between the measuring device and the measuring object. The measuring device and the driving device each have a synchronized timer. The drive device associates the information indicating the position of the measurement target with the time information from the timer indicating the timing at which the information indicating the position is acquired, and outputs the information as the first information. The measuring device associates the measurement information acquired by measuring the measurement target with the time information from the timer indicating the timing at which the measurement information is acquired, and outputs the second information. The measurement system calculates the position associated with the time information included in the second information based on one or more first information, and also with the calculated position associated with the common time information. It includes an information generation means for generating information indicating the shape of the measurement target based on the combination with the measurement information.

Preferably, the first information further includes information indicating the acceleration of the measurement target and information indicating the velocity, and the information generating means is based on the acceleration and velocity of the measurement target at a time before the time of the calculation target. The position at the time of the calculation target is calculated.

Preferably, the information generating means interpolates the information indicating the position included in the plurality of first information associated with the time in the vicinity of the time of the calculation target, and calculates the position at the time of the calculation target.

Preferably, the measuring device and the driving device are connected via a time-synchronized network.

Preferably, the measurement system further includes a communication master that manages data communication and timer synchronization on the network. The information generation means is provided in the communication master.

Preferably, the measuring device is configured to irradiate the measurement target with the measurement light and receive the reflected light from the measurement target to measure the characteristic value of the measurement target. The second information includes time information indicating an arbitrary timing from the start of irradiation of the measurement light to the completion of irradiation.

Preferably, the timing at which the driving device outputs the first information and the timing at which the measuring device outputs the second information are different from each other.

The measuring device according to another aspect of the present invention includes a network controller for connecting a measuring device for measuring a measurement target and a driving device for changing the relative positional relationship between the measuring device and the measuring target, and a timer for the measuring device. And a timer synchronized with the timer of the drive unit. The drive device associates the information indicating the position of the measurement target with the time information from the timer indicating the timing at which the information indicating the position is acquired, and outputs the information as the first information. The measuring device associates the measurement information acquired by measuring the measurement target with the time information from the timer indicating the timing at which the measurement information is acquired, and outputs the second information. The control device calculates the position associated with the time information included in the second information based on the one or more first information, and also with the calculated position associated with the common time information. It includes an information generation means for generating information indicating the shape of the measurement target based on the combination with the measurement information.

According to still another aspect of the present invention, there is provided a measurement method in a measurement system including a measurement device for measuring a measurement target and a drive device for changing the relative positional relationship between the measurement device and the measurement target. The measuring device and the driving device each have a synchronized timer. The measurement method includes a step in which the drive device associates the information indicating the position of the measurement target with the time information from the timer indicating the timing at which the information indicating the position is acquired and outputs the information as the first information. The step of associating the measurement information acquired by the measuring device by measuring the measurement target with the time information from the timer indicating the timing at which the measurement information was acquired and outputting it as the second information, and 1. Alternatively, the step of calculating the position associated with the time information included in the second information based on the plurality of first information, and the calculated position and the measured information associated with the common time information. It includes a step of generating information indicating the shape of the measurement target based on the combination.

The measurement system according to the present invention shows the shape of the measurement target even if the measurement device for the measurement target and the drive device that changes the relative positional relationship between the measurement device and the measurement target are not directly connected. Information can be generated with high accuracy.

It is a schematic diagram which shows the whole structure example of the measurement system which concerns on this embodiment. It is a schematic diagram which shows the hardware configuration example of the control device which constitutes the measurement system which concerns on this embodiment. It is a schematic diagram which shows the hardware configuration example of the drive unit which constitutes the measurement system which concerns on this embodiment. It is a schematic diagram which shows the hardware configuration example of the measuring apparatus which constitutes the measuring system which concerns on this embodiment. It is a figure for demonstrating the operation timing of the drive unit and the measuring apparatus in the measuring system which concerns on this embodiment. It is a figure for demonstrating the generation process of the shape information in the measurement system which concerns on this embodiment. It is a figure for demonstrating the generation process of the shape information in the measurement system which concerns on this embodiment. It is a sequence diagram which shows the processing procedure executed in the measurement system which concerns on this embodiment. It is a flowchart which shows the processing procedure in the drive unit which constitutes the measurement system which concerns on this embodiment. It is a flowchart which shows the processing procedure in the measuring apparatus constituting the measuring system which concerns on this embodiment. It is a figure for demonstrating the exchange and processing of information in the measurement system which concerns on this embodiment. It is a figure for demonstrating the interpolation processing of the motion information based on acceleration and velocity. It is a figure for demonstrating the interpolation process of the operation information based on the operation information of the neighborhood. It is a figure for demonstrating the dynamic determination process of the exposure time in the measuring apparatus constituting the measuring system which concerns on this embodiment. It is a figure for demonstrating the influence when the exposure time is dynamically determined in the measuring apparatus constituting the measuring system which concerns on this embodiment. It is a flowchart which shows the generation procedure of the shape information in the measurement system which concerns on this embodiment.

Embodiments of the present invention will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals and the description thereof will not be repeated.

<A. Overall configuration example of measurement system>
First, an example of the overall configuration of the measurement system 1 according to the present embodiment will be described. FIG. 1 is a schematic diagram showing an overall configuration example of the measurement system 1 according to the present embodiment.

With reference to FIG. 1, the measurement system 1 according to the present embodiment, as an example, determines the distances to a plurality of measurement points on a measurement target (hereinafter, also referred to as “work W”) arranged in the inspection device 2. By measuring optically, shape information indicating the surface shape of the work W is output.

In the present specification, "shape information" is information indicating the shape of a measurement target (work W), and is a concept including a correspondence relationship between an arbitrary position set in the measurement target and a measurement point for the position. be.

More specifically, the measurement system 1 includes a control device 100, a drive unit 200 connected to the control device 100 via a field network 20, and a measurement device 300 as main components. The measuring device 300 measures the work W to be measured.

As the field network 20, typically, a network that performs constant periodic communication is adopted, in which the arrival time of data is guaranteed. EtherCAT (registered trademark) or the like can be adopted as a network for performing such fixed-period communication.

As an example, the control device 100 functions as a communication master in the field network 20. The communication master manages the synchronization of timers between the devices connected to the field network 20, and also manages the communication schedule that defines the timing of data transmission / reception. That is, the control device 100, which is the communication master, manages the data communication on the field network 20 and the synchronization of the timer.

The drive unit 200 and the measuring device 300 function as communication slaves for transmitting and receiving data on the field network 20 according to instructions from the communication master.

More specifically, the control device 100 has a timer 102, the drive unit 200 has a timer 202, and the measuring device 300 has a timer 302. When the timer 102 of the control device 100 generates a synchronization signal such as a reference clock, the other timers 202 and 302 synchronize with the timer 102. Therefore, the data transmission / reception timing can be managed at a common time between the devices connected to the field network 20.

As described above, the drive unit 200 and the measuring device 300 each have a synchronized timer. By connecting the drive unit 200 and the measuring device 300 via the field network 20, which is a timing-synchronized network, the timers can be synchronized with each other.

In the present specification, "time" means information that identifies a point with a flow of time, and is commonly used in, for example, a field network, in addition to a time having a normal meaning defined by hours, minutes, seconds, and the like. It may contain a timer value or a counter value to be used. The "time" is basically managed by a timer of each device. In addition to the "time" itself, the "time information" includes information for specifying the "time" (for example, the result of encoding the "time" in some way, the elapsed time from a certain reference time, etc.). include.

Generally, in a master-slave type fixed-period network, any one or more devices may function as a communication master that manages synchronization between timers. The communication master does not necessarily have to be the control device 100, and for example, either the drive unit 200 or the measuring device 300 may function as the communication master.

The control device 100 is an arbitrary computer, and may be typically embodied as a PLC (programmable controller). The control device 100 gives an operation command to the drive unit 200 connected via the field network 20, and also receives information (including operation information and time information) from the drive unit 200. Further, the control device 100 gives a measurement command to the measurement device 300 and receives information (including measurement information and time information) from the measurement device 300. The control device 100 integrates the respective feedback responses from the drive unit 200 and the measuring device 300 to generate shape information about the work W. The details of the process of generating the shape information about the work W will be described later.

The control device 100 may execute some control calculation based on the shape information of the generated work W, and the shape information of the generated work W may be used as a higher-level device such as a manufacturing execution system (MES). You may send it to.

The drive unit 200 corresponds to a drive device that changes the relative positional relationship between the measuring device 300 and the work W to be measured. More specifically, the drive unit 200 drives a motor 10 that operates the inspection device 2 on which the work W is placed. For example, the drive unit 200 includes a servo driver, an inverter unit, and the like. The drive unit 200 applies AC power or pulse power for driving the motor 10 in accordance with an operation command from the control device 100, and at the same time, the operating state of the motor 10 (for example, rotation position (phase angle), rotation speed, rotation acceleration, and so on. (Torque, etc.) is acquired, and the specified information is transmitted to the control device 100 as operation information. When the motor 10 is equipped with an encoder (see the encoder 12 shown in FIG. 3), an output signal from the encoder is input to the drive unit 200.

The motor 10 is rotationally driven to change the position of the stage 6 constituting the inspection device 2. For example, the stage 6 is movably arranged on the base 4, and the stage 6 is engaged with the ball screw 14 . The motor 10 is mechanically coupled to the ball screw 14 via a speed reducer, and the rotational motion of the motor 10 is given to the ball screw 14. Due to the rotation of the ball screw 14, the relative positional relationship between the ball screw 14 and the stage 6 changes in the extending direction of the ball screw 14.

That is, by giving an operation command from the control device 100 to the drive unit 200, the position of the stage 6 of the inspection device 2 changes, and the work W arranged on the stage 6 also changes the position.

The measuring device 300 corresponds to a measuring unit that measures the displacement of the work W. In the present embodiment, the distance from the sensor head 310 electrically or optically connected to the measuring device 300 to the measuring point on the surface of the work W is assumed as the displacement with respect to the work W. For example, as the measuring device 300, an optical displacement sensor that optically measures the distance to the measuring point on the surface of the work W may be used. Specifically, the measuring device 300 irradiates the work W with the measured light from the sensor head 310, and the light is reflected by the work W to receive the light generated, so that the measuring point on the surface of the work W is received. Measure the distance to. As an example, a triangular ranging type optical displacement sensor or a coaxial confocal type optical displacement sensor may be used.

The measuring device 300 irradiates the work W with the measurement light and receives the reflected light from the work W to measure the characteristic value of the work W. More specifically, the measuring device 300 is calculated from the received reflected light while adjusting the measurement timing (for example, the intensity and timing of the measurement light irradiating the work W) according to the measurement command from the control device 100. The measurement information including the measurement result is transmitted to the control device 100.

The intensity and timing of the measured light applied to the work W controls the lighting time and lighting timing of the light source that generates the light, or the exposure time of the image pickup element that receives the reflected light from the work W. It may be adjusted by controlling the exposure timing.

In the measurement system 1 according to the present embodiment, time information associated with the operation information is added to the operation information transmitted from the drive unit 200 to the control device 100. This time information indicates the timing at which the associated operation information is acquired. In this way, the drive unit 200 correlates the information indicating the position of the work W with the time information from the timer indicating the timing at which the information indicating the position is acquired, and outputs the operation information (first information). do.

In the present specification, the "information indicating the position of the measurement target (work W)" includes the position of the inspection device 2 or the motor 10 mechanically connected to the work W in addition to the information indicating the position of the work W itself. Contains information indicating. That is, the "information indicating the position of the measurement target (work W)" includes any information that can directly or indirectly specify the position of the work W. Moreover, the number of dimensions of this information may be any. Further, the same applies to "information indicating the speed of the measurement target (work W)" and "information indicating the acceleration of the measurement target (work W)".

Similarly, the time information associated with the measurement information is added to the measurement information transmitted from the measurement device 300 to the control device 100. This time information indicates, for example, the timing at which the associated measurement information is acquired, or the timing at which the measurement light for acquiring the associated measurement information is irradiated. In this way, the measuring device 300 associates the measurement information acquired by measuring the work W with the time information from the timer indicating the timing at which the measurement information is acquired, and the measurement information (second). Information) is output.

The control device 100 uses the time information associated with each of the operation information and the measurement information to adjust the temporal relationship between the operation information and the measurement information, and then generates the shape information of the work W. More specifically, the control device 100 calculates a position associated with the time information included in the measurement information (second information) based on one or more operation information (first information), and also calculates a position associated with the time information. Information (shape information) indicating the shape of the work W is generated based on the combination of the calculated position and the measurement information associated with the common time information.

<B. Hardware configuration example of each device that configures the measurement system>
Next, a hardware configuration example of each device constituting the measurement system 1 according to the present embodiment will be described.

(B1: Control device)
FIG. 2 is a schematic diagram showing a hardware configuration example of the control device 100 constituting the measurement system 1 according to the present embodiment. With reference to FIG. 2, the control device 100 includes a processor 104, a main memory 106, a flash memory 108, a chip set 114, and a network controller 116, in addition to a timer 102 that manages communication timing and the like in the field network 20. , A memory card interface 118, an internal bus controller 122, and a field network controller 124.

The processor 104 is composed of a CPU (Central Processing Unit), an MPU (Micro-Processing Unit), and the like, and is controlled by reading various programs stored in the flash memory 108, expanding them in the main memory 106, and executing the processor 104. Control according to the above and various processes as described later are realized.

The flash memory 108 stores a user program 112 executed by the control device 100 in addition to the system program 110 for providing basic functions as the control device 100.

The system program 110 is a group of instructions for executing the processing necessary for executing the user program 112 in the control device 100.

The user program 112 is an instruction group arbitrarily created according to a control target or the like, and includes, for example, a sequence program 112A, a motion program 112B, and a shape information generation program 112C.

By controlling the processor 104 and each device, the chipset 114 realizes the processing of the control device 100 as a whole.

The network controller 116 exchanges data with a host device or the like via a host network.

The memory card interface 118 is configured so that a memory card 120, which is an example of a non-volatile storage medium, can be attached and detached, and data can be written to the memory card 120 and various data can be read from the memory card 120. ing.

The internal bus controller 122 is an interface for exchanging data with the I / O unit 126 mounted on the control device 100 via the internal bus 128.

The field network controller 124 is an interface that connects to a network between the drive unit 200 and other devices including the measuring device 300, and exchanges data via the field network 20. The field network controller 124 includes a synchronization management function 125 as a function as a communication master in the field network 20.

The synchronization management function 125 is based on the time from each device connected to the field network 20 (typically, the counter value output by the timer of each device) and the time from the timer 102. The time lag is calculated, and the synchronization signal after correcting the time lag is output to each device. In this way, the synchronization management function 125 synchronizes the timer 102 with the timer of the drive unit 200 and the timer of the measuring device 300.

FIG. 2 shows a configuration example in which the necessary functions are provided by the processor 104 executing a program, and some or all of these provided functions are provided by a dedicated hard-wired circuit (for example, ASIC). (Application Specific Integrated Circuit) or FPGA (Field-Programmable Gate Array), etc.) may be used for implementation. Alternatively, the main part of the control device 100 may be realized by using hardware that follows a general-purpose architecture (for example, an industrial controller based on a general-purpose computer). In this case, a virtualization technique may be used to execute a plurality of OSs (Operating Systems) having different uses in parallel, and to execute necessary applications on each OS.

(B2: Drive unit 200)
FIG. 3 is a schematic diagram showing a hardware configuration example of the drive unit 200 constituting the measurement system 1 according to the present embodiment. With reference to FIG. 3, the drive unit 200 includes a field network controller 204 including a timer 202 for managing communication timing and the like in the field network 20, a drive controller 206, a main circuit 208, and a pulse counter 210.

The field network controller 204 is an interface for exchanging data with and from other devices including the control device 100 and the measuring device 300 via the field network 20.

The drive controller 206 generates a command value according to a predetermined calculation logic according to an operation command from the control device 100. More specifically, the drive controller 206 has a control calculation logic that combines necessary control loops such as a position control loop, a speed control loop, and a torque control loop. The drive controller 206 calculates the operating state of the target motor 10 from the count value counted by the pulse counter 210 and outputs it to the control device 100.

The drive controller 206 has a software implementation that realizes the necessary processing and functions by causing the processor to execute a program, and a hardware implementation that realizes the necessary processing and functions by using a hard-wired circuit such as an ASIC or FPGA. It may be realized.

The main circuit 208 is configured to include, for example, a converter circuit and an inverter circuit, and generates a predetermined current waveform or voltage waveform according to a command from the drive controller 206 and feeds it to the connected motor 10.

The pulse counter 210 counts the pulse signal from the encoder 12 mounted on the motor 10 and outputs the count value to the drive controller 206.

The main circuit 208, the pulse counter 210, and the like may be appropriately changed according to the electrical characteristics or mechanical characteristics of the motor 10 to be driven.

(B3: Measuring device 300)
FIG. 4 is a schematic diagram showing a hardware configuration example of the measuring device 300 constituting the measuring system 1 according to the present embodiment. With reference to FIG. 4, the measuring device 300 includes a field network controller 304 including a timer 302 for managing communication timing and the like in the field network 20, an image pickup controller 306, and a data processing unit 308.

The field network controller 304 is an interface for exchanging data with and from other devices including the control device 100 and the drive unit 200 via the field network 20.

The image pickup controller 306 gives an irradiation command to the sensor head 310 according to an operation command from the control device 100. The data processing unit 308 calculates the distance to the measurement point on the surface of the work W based on the received light signal from the sensor head 310.

The sensor head 310 connected to the measuring device 300 includes a light emitting source 312, a light receiving element 314, and a lens 316.

The light emitting source 312 is a light source that is driven according to a command from the image pickup controller 306 to generate predetermined light, and is composed of, for example, a white LED (Light Emitting Diode) or a semiconductor laser.

The light receiving element 314 is an element that receives the reflected light from the target work W and outputs the light receiving signal to the data processing unit 308. For example, a light receiving element (line sensor) having a one-dimensional arrangement or a light receiving element (line sensor) having a two-dimensional arrangement. It is composed of a light receiving element (CCD (Charge Coupled Device), etc.).

The lens 316 is an optical system that adjusts the focal position of the measurement light emitted from the sensor head 310 and the light reflected from the work W.

Since the optical configuration and the electrical configuration of the sensor head 310 are appropriately designed according to the measurement principle, the configuration is not limited to the configuration shown in FIG.

<C. Shape information generation process>
Next, the shape information generation process executed in the measurement system 1 according to the present embodiment will be described.

FIG. 5 is a diagram for explaining the operation timing of the drive unit 200 and the measuring device 300 in the measuring system 1 according to the present embodiment. With reference to FIG. 5, the drive unit 200 and the measuring device 300 execute processing at a cycle corresponding to their respective characteristics. Therefore, the timing and cycle in which the drive unit 200 controls the operation with respect to the motor 10 in response to the operation command does not match the timing and cycle in which the measuring device 300 measures the distance to the work W.

In the example shown in FIG. 5, the drive unit 200 controls at the operation times TS1, TS2, ... (Time interval ΔTS) and outputs operation information. On the other hand, the measuring device 300 performs measurement processing (distance measurement) on the work W at the measurement times TZ1, TZ2, ... (Time interval ΔTZ). Since the distance measured by the measuring device 300 corresponds to a value calculated from the optical characteristics of the imaging data from the start of imaging to the completion of imaging, the acquired measurement information includes imaging for performing the measurement information. May be associated with a time indicating the timing at which is completed.

The shape information (that is, the profile) indicating the surface shape of the work W indicates the relationship between the relative positional relationship between the sensor head 310 and the work W and the distance to the work W measured in the relative positional relationship. Yes, both relative positional relationships and distances should be obtained at the same time.

As shown in FIG. 5, since the drive unit 200 and the measuring device 300 do not control and measure in synchronization with each other, the operation information and the measurement information are not output at the same time at a common timing. That is, the timing at which the drive unit 200 outputs the operation information and the timing at which the measuring device 300 outputs the measurement information may be different from each other.

In the measurement system 1 according to the present embodiment, since the control device 100, the drive unit 200, and the measurement device 300 have timers synchronized with each other, the time axis of the time information output by each device is standardized. Can be considered to be. Therefore, the drive unit 200 outputs the operation information in association with the time information, and the measuring device 300 outputs the measurement information in association with the time information. Then, the control device 100 generates shape information about the work W by matching the timing of the operation information from the drive unit 200 and the measurement information from the measurement device 300 with reference to the time information.

6 and 7 are diagrams for explaining the shape information generation process in the measurement system 1 according to the present embodiment.

With reference to FIG. 6, based on the information (operation information and time information) from the drive unit 200 and the information (measurement information and time information) from the measuring device 300, the operation information and the operation information and the time information are used as the reference. A table 400 in which the measurement information is arranged in time series is generated. That is, the control device 100 tabulates the operation information, the measurement information, and the time information acquired from the drive unit 200 and the measurement device 300 in chronological order.

More specifically, the table 400 is composed of a record including operation information 404, measurement information 406, and time information 402.

As shown in the table 400 of FIG. 6, the operation information 404 from the drive unit 200 and the measurement information 406 from the measuring device 300 are not always acquired at the same time. By interpolating or estimating the information of, the combination of the operation information 404 and the measurement information 406 at the same time is determined.

In the example shown in FIG. 6, the operation information at the time when the measurement information 406 is acquired is calculated by interpolating the operation information 404. Here, the operation information may include information indicating the acceleration of the work W and information indicating the speed, in addition to the position at each time. By using such speed and acceleration information, the position at a specified time can be calculated.

More specifically, in the table 400 of FIG. 6, the operation information 408 ( operation information 12 ) associated with the measurement information 1 at the measurement time TZ1 is in the operation time TS2 adjacent to the operation information 1 in the adjacent operation time TS1. It is calculated by interpolating with the operation information 2. In this way, the control device 100 determines the operation information associated with the measurement time of the measurement information output by the measurement device 300 by interpolating based on the adjacent operation information.

By performing such interpolation processing for each measurement time associated with the measurement information, a table 410 associated with the time series as shown in FIG. 6 is generated. Table 410 is composed of a record including operation information 414, measurement information 416, and time information 412. When the position included in the operation information 414 and the measurement information 416 are plotted in association with each other based on each table constituting the table 410, the shape information 420 as shown in FIG. 6 is output.

For convenience of explanation, a processing example using a table has been described, but the present invention is not limited to this, and any data processing technique may be used for implementation. That is, any process may be adopted as long as it generates shape information by generating a combination of operation information and measurement information associated with a common time.

The shape information generation process as shown in FIG. 6 may be substantially as long as the process as shown in FIG. 7 can be realized. In FIG. 7, the temporal change 424 of the motion information indicating the change of the motion information with respect to the time information and the temporal change 426 of the measurement information indicating the change of the measurement information with respect to the time information are aligned with the coordinates of the common time information. ing. Further, with respect to the temporal change 424 of the operation information, the operation information at the time when the operation information is not actually acquired is also estimated by the interpolation processing. By integrating these two temporal changes and erasing the time information, it is possible to generate shape information 420 indicating changes in measurement information with respect to motion information.

The generation process shown in FIGS. 6 and 7 described above is typically executed by the control device 100, but is not limited to this, and may be executed by the drive unit 200 or the measuring device 300.

<D. Processing procedure>
Next, the processing procedure in the measurement system 1 according to the present embodiment will be described.

(D1: Overall processing sequence)
FIG. 8 is a sequence diagram showing a processing procedure executed in the measurement system 1 according to the present embodiment. In the sequence diagram shown in FIG. 8, the processor 104 and the field network controller 124 of the control device 100, the field network controller 204 and the drive controller 206 of the drive unit 200, the field network controller 304 of the measuring device 300, the image pickup controller 306, and the data processing. Focusing on the processing executed with the unit 308.

As described above, timing synchronization is performed between the devices connected to the field network 20, and this timing synchronization is managed by the field network controller 124 of the control device 100 as an example. Specifically, the field network controller 124 of the control device 100 is a time from each device (communication slave) included in a frame sequentially transmitted through the field network 20 (a count value output by a timer managed by each communication slave). Based on the above, the timing deviation amount (time deviation amount) in each device is calculated (sequence SQ100), and a synchronization signal for correcting the calculated timing deviation amount is transmitted to each device (sequence SQ102). Each device (communication slave) corrects the managed timer according to the synchronization signal from the field network controller 124 of the control device 100. This synchronization signal specifies the time after time shift correction.

The processes of the sequence SQ100 and the sequence SQ102 may be executed at predetermined cycles or at predetermined events independently of other processes.

As a control operation for the motor 10 in the drive unit 200, the drive controller 206 of the drive unit 200 executes a control process according to an operation command given in advance (sequence SQ110). At this time, the drive controller 206 acquires operation information based on the execution result of the control process and the like. Further, the drive controller 206 acquires the time information associated with the execution timing of the control process from the field network controller 204 (timer 202) (sequence SQ112).

Then, the drive controller 206 transmits the acquired operation information to the control device 100 via the field network controller 204 (sequence SQ114), and transmits the associated time information to the control device 100 via the field network controller 204. Transmit (sequence SQ116). The operation information and the associated time information transmitted from the drive unit 200 are stored in the main memory 106 or the like accessible to the processor 104 of the control device 100.

As a measurement process for the work W in the measuring device 300, the data processing unit 308 of the measuring device 300 indicates to the image pickup controller 306 at what timing during the image pickup period (exposure period) the time information is acquired. Notify the acquisition timing of information (sequence SQ120). Subsequently, the image pickup controller 306 starts the image pickup process according to the image pickup conditions specified in advance (sequence SQ122). Further, the image pickup controller 306 acquires the time information associated during the image pickup period from the field network controller 304 (timer 302) according to the acquisition timing of the time information (sequence SQ124). Then, the image pickup controller 306 outputs the image pickup signal output from the image pickup element to the data processing unit 308 (sequence SQ126), and outputs the associated time information (sequence SQ128).

The data processing unit 308 executes measurement processing based on the image pickup signal from the image pickup controller 306 to generate measurement information (sequence SQ130). Then, the data processing unit 308 transmits the generated measurement information to the control device 100 via the field network controller 304 (sequence SQ132), and the associated time information is transmitted to the control device 100 via the field network controller 304. (Sequence SQ134). The measurement information transmitted from the measurement device 300 and the associated time information are stored in the main memory 106 or the like accessible to the processor 104 of the control device 100.

The control operation for the motor 10 (sequence SQ110 to SQ116) and the measurement process for the work W (sequence SQ120 to SQ134) shown in FIG. 8 are repeated a predetermined number of times. When a series of measurement processes for the work W are completed, the processor 104 of the control device 100 generates shape information based on the stored operation information, measurement process, and time information (sequence SQ140).

The series of processes as described above is repeated for each work W.
(D2: Processing procedure in the drive unit 200)
Next, the processing procedure in the drive unit 200 constituting the measurement system 1 according to the present embodiment will be described. FIG. 9 is a flowchart showing a processing procedure in the drive unit 200 constituting the measurement system 1 according to the present embodiment.

With reference to FIG. 9, when the drive unit 200 receives the synchronization signal (step S200), the drive unit 200 executes a process for correcting the time lag (step S202).

Further, the drive unit 200 executes a process of determining operation information from a control operation for the motor 10 (step S204) and a process of determining associated time information (step S206). Then, the drive unit 200 outputs the determined operation information and time information (step S208). An output record including these associated operation information and time information is stored in the control device 100.

(D3: Processing procedure in the measuring device 300)
Next, the processing procedure in the measuring device 300 constituting the measuring system 1 according to the present embodiment will be described. FIG. 10 is a flowchart showing a processing procedure in the measuring device 300 constituting the measuring system 1 according to the present embodiment.

With reference to FIG. 10, when the measuring device 300 receives the synchronization signal (step S300), the measuring device 300 executes a process of correcting the time lag (step S302).

Further, the measuring device 300 executes an imaging process such as irradiation of the measurement light on the work W (step S304), determines measurement information based on the imaging result (step S306), and associates time information. Is executed (step S308). Then, the measuring device 300 outputs the determined measurement information and the time information (step S310). An output record including these associated measurement information and time information is stored in the control device 100.

<E. Operation information interpolation processing>
Next, some implementation examples will be described with respect to the interpolation processing of the operation information in the measurement system 1 according to the present embodiment.

FIG. 11 is a diagram for explaining the exchange and processing of information in the measurement system 1 according to the present embodiment. For convenience of explanation, FIG. 11 shows an example in which the drive unit 200 and the measuring device 300 cyclically execute the processes in the same control cycle, but the process is not limited to this, and the processes are executed in their own control cycles. May be good. Further, it may be an aperiodic process such as for each specific event.

In the example shown in FIG. 11, the drive unit 200 outputs the position Sx, the velocity Vsx, and the acceleration Asx (where x indicates an index number) associated with each operation time TSx as operation information. Further, the measuring device 300 outputs the measured value Dzx (where x indicates an index number) associated with each measurement time TZx as the measurement information.

(E1: Interpolation process 1)
In the measurement system 1 according to the present embodiment, the operation information is information from the motor 10 rotationally driven by the drive unit 200. Considering the characteristics of such a rotationally driven mechanical system, it is considered that the velocity changes linearly with time within a sufficiently short time. That is, assuming that the acceleration acquired at the immediately preceding operation time is constant, the speed at the measurement time for which the operation information is to be estimated is the speed obtained by multiplying the acceleration at the immediately preceding operation time by the elapsed time. It can be calculated by adding or subtracting changes.

That is, since the speed at the immediately preceding operation time is known and the speed at the measurement time of the estimation target can be estimated, the position of the estimation target can be calculated from the relationship between the two speeds.

FIG. 12 is a diagram for explaining interpolation processing of motion information based on acceleration and velocity. In FIG. 12, a case where the position S (TZ2) at the measurement time TZ2 shown in FIG. 11 is estimated will be described as an example.

With reference to FIG. 12A, it is assumed that the velocity Vs1 and the acceleration As1 are acquired as the operation information at the operation time TS1. Assuming that the acceleration As1 is maintained from the operation time TS1 to the measurement time TZ2 to be estimated, the velocity Vs (TZ2) at the measurement time TZ2 can be calculated as follows.

Vs (TZ2) = Vs1 + ΔVs = Vs1 + As1 × (TZ2-TS1)
Since the position at the operation time TS1 is the position S1 with reference to FIG. 12B, it is obtained by adding the moving distance from the operation time TS1 to the measurement time TZ2 to the position S1 in consideration of the above-mentioned speed change. , The position S (TZ2) at the measurement time TZ2 can be calculated as follows.

S (TZ2) = [{Vs1 + As1 × (TZ2-TS1)} ² -Vs1 ² ] / 2 × As1
As described above, the position at the time of the calculation target may be calculated based on the acceleration and the speed of the work W at the time before the time of the calculation target.

(E2: Interpolation process 2)
In the measurement system 1 according to the present embodiment, operation information can be acquired periodically. Therefore, among the time-series operation information, the operation information in the vicinity of the measurement time of the estimation target is used for interpolation processing. , The position at the measurement time of the target can be estimated.

FIG. 13 is a diagram for explaining the interpolation processing of the operation information based on the operation information in the vicinity. With reference to FIG. 13, for example, it is assumed that the positions at the operation times TS1, TS2, and TS3 are the positions S1, S2, and S3, respectively. For example, a case where the position S (TZ2) at the measurement time TZ2 between the operation time TS2 and the operation time TS3 is estimated will be described as an example.

In this case, for example, the interpolation formula can be determined using the information of the positions S1, S2, and S3 at the operation times TS1, TS2, and TS3, and the position S (TZ2) can be estimated based on the determined interpolation formula.

As the interpolation method, a known interpolation method can be adopted. As such known interpolation methods, linear interpolation, Lagrange interpolation, spline interpolation and the like are known. For example, if Lagrange interpolation is applied using the operation information of the operation times TS1, TS2, and TS3 in the vicinity of the measurement time TZ2, the position S (TZ2) can be estimated as follows.

S (TZ2) = S1 × (TZ2-T2) (TZ2-TS3) / (TS1-TS2) (TS1-TS3) + S2 × (TZ2-T1) ( TZ2 -TS3) / (TS2-TS1) (TS2- TS3) + S3 × (TZ2-T1) ( TZ2 -TS2) / (TS3-TS1) (TS3-TS2)

As described above, the position at the time of the calculation target is calculated by interpolating the information indicating the position included in the plurality of operation information (first information) associated with the time in the vicinity of the time of the calculation target. You may.

(E3: Supplement)
In the measurement system 1 according to the present embodiment, since the time information (operation time) associated with the operation information is transmitted to the control device 100, the timing associated with each operation information can be specified. However, when the control operation in the drive unit 200 is cyclically executed at predetermined control cycles managed on the field network 20, each operation information is received even when only the operation information is received from the drive unit 200. The time information (operation time) associated with can be calculated. Therefore, as long as the measurement time to be estimated can be specified, the operation information (position) at the measurement time can be estimated by any of the above methods.

In the above description, an example is shown in which the drive unit 200 periodically executes a control operation, and operation information is also periodically transmitted in synchronization with the control operation, but such a periodic control operation is not always necessary. is not it. If at least the time information (operation time) associated with the operation information is transmitted to the control device 100, the operation information (position) at the target measurement time can be estimated by any of the above methods.

Further, FIG. 11 shows an example in which both the drive unit 200 and the measuring device 300 cyclically execute the processing at predetermined cycles, but the present invention is not limited to this, and both or one of the drive unit 200 and the measuring device 300 execute the processing at different cycles, or Even in the case where the process is executed as an event, the operation information (position) can be estimated by the method as described above. That is, in the measurement system 1 according to the present embodiment, since each device connected to the field network 20 has a timing-synchronized timer, the time information from such a timing-synchronized timer is used. As a result, even in a form in which each device transmits information at its own cycle, the information can be aggregated based on the time in the communication master (control device 100) or the like.

In the above description, an example of interpolating the operation information (position) output by the drive unit 200 to estimate the operation information (position) associated with each measurement time has been described, but the reverse may be performed. That is, the measurement information output by the measurement device 300 may be interpolated to estimate the measurement information associated with each operation time.

<F. Dynamic determination of exposure time>
In the measuring device 300 constituting the measuring system 1 according to the present embodiment, a function of dynamically determining the imaging length (exposure time) may be implemented. In such a case, the measurement point on the surface of the work W actually measured by the measuring device 300 also fluctuates, so that the time information associated with the measurement information is also dynamically determined as the imaging time. It is necessary to correct according to.

FIG. 14 is a diagram for explaining a dynamic determination process of an exposure time in the measuring device 300 constituting the measuring system 1 according to the present embodiment. With reference to FIG. 14, for example, it is assumed that the measurement process for the work W is repeatedly executed every predetermined measurement cycle Ts. At this time, it is assumed that after the imaging process is executed over a certain imaging length Texp , some processing result is obtained by the data processing for the imaging signal obtained by the imaging process. Based on the obtained processing result, it is possible to determine the excess or deficiency of the exposure. Then, when it is determined that the exposure is insufficient, an imaging length longer than the previous imaging length is set, and the next imaging process is executed. On the other hand, when it is determined that the exposure is excessive, an imaging length shorter than the previous imaging length is set, and the next imaging process is executed.

In this way, the imaging length (that is, the exposure time) of the subsequent imaging process may be dynamically determined based on the processing result obtained by the previous imaging process. Such automatic adjustment for the imaging length (exposure time) is executed within a preset maximum imaging length range. In other words, the imaging length will fluctuate by a preset maximum length.

FIG. 15 is a diagram for explaining the influence when the exposure time is dynamically determined in the measuring device 300 constituting the measuring system 1 according to the present embodiment. 15 (A) to 15 (C) show a state in which the stage 6 on which the work W is arranged is moving from the left side of the paper surface to the right side of the paper surface. With such movement of the work W, the relative positional relationship between the work W and the sensor head 310 changes with time. Therefore, as the imaging length (exposure time) changes, the position on the surface of the work W irradiated with the measurement light also changes.

As an example, as shown in FIG. 15A, when the imaging length Texp is relatively short, the measurement light is irradiated to the right side of the paper surface of the work W. On the other hand, as shown in FIG. 15C, when the imaging length Texp is relatively long, the measurement light is irradiated to the left side of the paper surface of the work W. Further, as shown in FIG. 15B, when the imaging length Texp is a standard length, the measurement light is irradiated to an intermediate position between the two.

It is necessary to appropriately reflect such fluctuations in the irradiation position of the measurement light to generate correct shape information.

With reference to FIG. 14 again, the measurement information from the measuring device 300 includes the measured value (in the above example, the distance to the surface of the work W), and the time information associated with the measurement information includes. For example, the measurement time TZ1 indicating the start timing of the measurement cycle Ts and the imaging length Texp may be included. The control device 100 may calculate the original measurement time by correcting the measurement time TZ1 included in the time information from the measurement device 300 with the imaging length Texp. In this case, the measurement point on the surface of the work W is a position associated with the timing of the measurement times TZ'1, TZ'2, TZ'3 ....

Further, depending on the application, it may be preferable to set the position associated with the center of the imaging period as the measurement point. In this case, the measurement time TZ''1, TZ''2, TZ''3 ... Can be calculated.

Further, in the above description, an example of transmitting the measurement time TZ1 and the imaging length Texp indicating the start timing of the measurement cycle Ts has been described, but the measurement time TZ'1, TZ'2, TZ'on the measuring device 300 side. 3 ... Or, the measurement time TZ "1, TZ" 2, TZ "3 ... may be calculated and then transmitted to the control device 100 as time information.

As described above, the time information obtained by the measuring device 300 includes the time information indicating an arbitrary timing from the start of irradiation of the measurement light to the completion of irradiation. That is, the time information obtained by the measuring device 300 is any of the timing corresponding to the start of irradiation of the measurement light, the arbitrary timing during the irradiation period of the measurement light, and the timing corresponding to the completion of the irradiation of the measurement light. May be good.

When the measuring device 300 is equipped with a function for dynamically determining the imaging length (exposure time), the measurement time associated with the imaging length (exposure time) is acquired and acquired. It is preferable to notify the control device 100 of the measured measurement time. In this case, any method can be adopted for notifying the control device 100 of the measurement time in what data format.

<G. Shape information generation processing procedure>
Next, the processing procedure related to the generation of shape information will be described.

FIG. 16 is a flowchart showing a procedure for generating shape information in the measurement system 1 according to the present embodiment. Each step shown in FIG. 16 is typically realized by the processor 104 of the control device 100 executing a program.

With reference to FIG. 16, when the control device 100 receives the information (operation information and the associated time information) from the drive unit 200 (YES in step S100), the control device 100 stores the received information using the time information as a key (step). S102). Otherwise (NO in step S100), the process of step S102 is skipped.

When the information (measurement information and the associated time information) from the measuring device 300 is received (YES in step S104), the received information using the time information as a key is stored (step S106). Otherwise (NO in step S104), the process of step S106 is skipped.

Subsequently, when the generation of the shape information is instructed (YES in step S108), the control device 100 specifies the time information associated with the measurement information included in the information from the stored measuring device 300 (step). S110), the operation information (position) associated with the specified time information is calculated using the information from the stored drive unit 200 (step S112). By the processing of step S110 and step S112, it is possible to determine the combination of measurement information and operation information (position) associated with a certain time information.

Then, the control device 100 determines whether or not the combination of the measurement information and the operation information (position) can be determined for all the time information included in the information from the stored measurement device 300 (step S114). If there is time information for which the combination of measurement information and operation information (position) has not been determined (NO in step S114), the processing of step S110 or less is repeated.

On the other hand, when the combination of the measurement information and the operation information (position) is determined for all the time information (YES in step S114), the measurement information is obtained based on the combination of the measurement information and the operation information (position). Generate (step S116). Then, the process ends.

<H. Modification example>
In the measurement system 1 according to the present embodiment, a configuration example in which the control device 100 acquires information from the drive unit 200 and the measurement device 300 to generate shape information has been described, but either the drive unit 200 or the measurement device 300 The shape information may be generated. That is, although the configuration in which the function for generating shape information is provided in the communication master of the field network 20 is exemplified, it may be arranged on another device.

In the measurement system 1 according to the present embodiment, the drive unit 200 and the measurement device 300 are connected to a single field network 20, but they may be connected to different field networks. For example, it is assumed that the control device functions as a communication master for each of the two field networks, and the timers for the respective field networks are synchronized in the control device. In such a configuration, timing synchronization can be realized between different field networks, so there is no need to standardize the field networks.

In the measurement system 1 according to the present embodiment, a configuration example in which one drive unit 200 and one measurement device 300 are arranged is shown, but the present invention is not limited to this, and a plurality of drive units 200 and the measurement device 300 may be arranged. good. For example, an XY stage having two degrees of freedom may be adopted as the stage 6, and two drive units 200 may be arranged to drive the respective motors 10 arranged along the respective axes. Even in this case, since the devices are time-synchronized with each other, the information acquired from each device can be aggregated on the same time axis.

In the measurement system 1 according to the present embodiment, since the operation information (position) and the measurement information associated with the time information defined on the same time axis can collect time-series data, some abnormality or event occurs. In that case, if the information on the time of occurrence can be obtained, the information at that timing can be specified, which helps to investigate the cause.

<I. Advantages>
In the measurement system according to the present embodiment, the measurement device for the measurement target and the drive device for changing the relative positional relationship between the measurement device and the measurement target each have a synchronized timer for measurement. Time information output from each timer is added to the measurement information from the device and the operation information from the drive device. By associating the measurement information and the operation information with each other based on this time information, it is possible to generate information indicating the shape of the measurement target with high accuracy even if the respective devices are not directly connected.

It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims, not the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 measurement system, 2 inspection equipment, 4 bases, 6 stages, 10 motors, 12 encoders, 14 ball screws, 20 field networks, 100 controllers, 102, 202, 302 timers, 104 processors, 106 main memory, 108 flash memory, 110 System Program, 112 User Program, 112A Sequence Program, 112B Motion Program, 112C Shape Information Generator, 114 Chipset, 116 Network Controller, 118 Memory Card Interface, 120 Memory Card, 122 Internal Bus Controller, 124, 204, 304 Field Network Controller, 125 synchronization management function, 126 I / O unit, 128 internal bus, 200 drive unit, 206 drive controller, 208 main circuit, 210 pulse counter, 300 measuring device, 306 imaging controller, 308 data processor, 310 sensor head, 312 Light emitting source, 314 light receiving element, 316 lens, 400,410 table, 402,412 time information, 404,414 operation information, 406,416 measurement information, 420 shape information, 424,426 temporal change, W work.

Claims (8)

It ’s a measurement system,
A measuring device that measures the measurement target and
A drive device that changes the relative positional relationship between the measuring device and the measuring target is provided.
The measuring device and the driving device each have a synchronized timer.
The measuring device and the driving device are connected via a wired network that performs timing-synchronized fixed-period communication .
The drive device correlates the information indicating the position of the measurement target with the time information from the timer indicating the timing at which the information indicating the position is acquired, and outputs the information as the first information.
The measuring device associates the measurement information acquired by measuring the measurement target with the time information from the timer indicating the timing at which the measurement information is acquired, and outputs the second information.
The measurement system calculates a position associated with the time information included in the second information based on one or a plurality of the first information, and is associated with the common time information. A measurement system including an information generation means for generating information indicating the shape of the measurement target based on a combination of the position and the measurement information. The first information further includes information indicating the acceleration and information indicating the velocity of the measurement target.
The measurement system according to claim 1, wherein the information generation means calculates a position at the time of the calculation target based on the acceleration and speed of the measurement target at a time before the time of the calculation target. The information generating means interpolates information indicating a position included in a plurality of the first information associated with a time in the vicinity of the time to be calculated, and calculates a position at the time to be calculated. Item 1. The measurement system according to item 1. Further equipped with a communication master that manages data communication and timer synchronization on the wired network.
The measurement system according to any one of claims 1 to 3, wherein the information generation means is provided in the communication master. The measuring device is configured to irradiate the measurement target with the measurement light and receive the reflected light from the measurement target to measure the characteristic value of the measurement target.
The measurement system according to any one of claims 1 to 4, wherein the second information includes time information indicating an arbitrary timing from the start of irradiation of the measurement light to the completion of irradiation. The measurement according to any one of claims 1 to 5, wherein the timing at which the driving device outputs the first information and the timing at which the measuring device outputs the second information are different from each other. system. It ’s a control device,
A network controller that connects a measurement device that measures a measurement target and a drive device that changes the relative positional relationship between the measurement device and the measurement target via a network.
A timer synchronized with the timer of the measuring device and the timer of the driving device is provided.
The measuring device and the driving device are connected via a wired network that performs timing-synchronized fixed-period communication .
The drive device correlates the information indicating the position of the measurement target with the time information from the timer indicating the timing at which the information indicating the position is acquired, and outputs the information as the first information.
The measuring device associates the measurement information acquired by measuring the measurement target with the time information from the timer indicating the timing at which the measurement information is acquired, and outputs the second information. Further, based on one or a plurality of the first information, the position associated with the time information included in the second information is calculated, and the calculated position and the measurement associated with the common time information are calculated. A control device including an information generation means for generating information indicating the shape of the measurement target based on a combination with the information. A measurement method in a measurement system including a measurement device for measuring a measurement target and a drive device for changing the relative positional relationship between the measurement device and the measurement target, wherein the measurement device and the drive device are synchronized. The measuring device and the driving device are connected to each other via a wired network that performs timing-synchronized fixed-period communication .
A step of associating the information indicating the position of the measurement target with the time information from the timer indicating the timing at which the information indicating the position is acquired and outputting the information as the first information.
A step in which the measuring device associates the measurement information acquired by measuring the measurement target with the time information from the timer indicating the timing at which the measurement information is acquired, and outputs the second information. When,
A step of calculating a position associated with the time information included in the second information based on one or more of the first information, and a step of calculating the position associated with the time information.
A measurement method comprising a step of generating information indicating the shape of the measurement target based on a combination of a calculated position and measurement information associated with common time information.

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