input / output devices

Abstract

To provide a technology which enables the light reception result of a sensor to be output to an external device by reducing data amount while maintaining the characteristics of the light reception result.SOLUTION: In communication between an external device and an input / output device that acquires the light reception result of a sensor having a plurality of light reception units, each of the light reception units receiving light emitted from a plurality of light projection units, and that outputs the acquired light reception result to the external device, a maximum amount of data transmittable per unit time is smaller than in communication between the input / output device and the sensor. The input / output device comprises acquisition means acquiring the light reception result, analysis means analyzing the light reception result and detecting a boundary between a portion where the sensor has been able to receive the light and a portion where the sensor has not been able to receive the light, and output means outputting data that indicates the position of the boundary detected by the analysis means to the external device.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a technique for inputting and outputting data. [Background technology]

[0002] Systems including safety light curtains are known as sensing systems for detecting the intrusion of workers into hazardous areas, the passage of transported goods, etc. A safety light curtain includes a light projector having multiple light projecting parts and a light receiver (sensor) having multiple light receiving parts.

[0003] Since a safety light curtain has many light receiving elements (and light emitting elements), the amount of data from the light receiving results of the multiple light receiving elements is also large. As a result, the speed of the transmission path between the safety light curtain and the external device (the maximum amount of data that can be transmitted per unit time) becomes a bottleneck, and the data from the light receiving results of the multiple light receiving elements may not be transmitted to the external device in a timely manner. In such cases, problems arise such as the external device being unable to reflect the light receiving results in its processing in real time.

[0004] Patent Document 1 discloses that an evaluation result as to whether or not the light receiving results of the sensor (light receiving results of a plurality of light receiving parts) satisfy a predetermined standard is stored. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] European Patent No. 3214466 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the technology disclosed in Patent Document 1, the evaluation result is data on whether a predetermined standard is satisfied or not, that is, binary data. Therefore, if this evaluation result is output to an external device instead of the light reception result of the sensor (light reception result of multiple light receiving parts), the accuracy of the processing performed by the external device (processing based on the light reception result of the sensor) will be significantly reduced.

[0007] The present invention has been made in consideration of the above-mentioned circumstances, and has an object to provide a technique that can output the light reception results of a sensor to an external device with a reduced amount of data while maintaining the sensor's characteristics. [Means for solving the problem]

[0008] In order to achieve the above object, the present invention employs the following configuration.

[0009] A first aspect of the present invention provides an input / output device that acquires the light reception result of a sensor having a plurality of light receiving parts that respectively receive light emitted from a plurality of light emitting parts and outputs the result to an external device, wherein communication between the input / output device and the external device has a smaller maximum amount of data that can be transmitted per unit time than communication between the input / output device and the sensor, and the input / output device has an acquisition means for acquiring the light reception result, an analysis means for analyzing the light reception result and detecting the boundary between parts of the sensor that were able to receive light and parts that were not able to receive light, and an output means for outputting data indicating the position of the boundary detected by the analysis means to the external device.

[0010] For example, the acquisition means is an input terminal, the analysis means is a processor, and the output means is is an output terminal, etc. The light receiving result of the sensor is, for example, data indicating the amount of light received for each light receiving section, data indicating whether or not each light receiving section was able to receive light, etc. The communication between the input / output device and the external device may be wired communication or wireless communication, for example, communication conforming to a standard such as IO-Link or Bluetooth. The part of the sensor that was able to receive light is, for example, a part where the amount of light received is equal to or greater than a threshold. The part of the sensor that was not able to receive light is, for example, a part where the amount of light received is less than a threshold. The position of the boundary between the part of the sensor that was able to receive light and the part that was not able to receive light is, for example, the intermediate position between two light receiving sections adjacent to each other across the boundary (the light receiving section that was able to receive light and the light receiving section that was not able to receive light), the position of one of the two light receiving sections, etc. The external device is, for example, a PLC (Programmable Logic Controller).

[0011] Generally, the data size is reduced by reducing the number of values ​​indicated by the data. Therefore, the size of the data indicating the position of the boundary between the part of the sensor that can receive light and the part that cannot receive light is smaller than the light reception result of the sensor (the light reception result of multiple light receiving parts). Also, if the position of such a boundary is known, it is possible to grasp the outline of an object passing between multiple light projecting parts and multiple light receiving parts.

[0012] According to the above-mentioned configuration, data indicating the position of the boundary between the part of the sensor that can receive light and the part that cannot receive light is output to the external device instead of the light reception result of the sensor. In this way, the amount of data output to the external device can be reduced compared to the case where the light reception result of the sensor is output to the external device as it is. In addition, the external device can grasp the outer shape of the object passing between the multiple light projecting units and the multiple light receiving units. The light from the multiple light projecting units is basically blocked by the object, but if there is a hole in the object, the light reaches the light receiving unit through the hole. Therefore, the external device can also grasp the hole in the object from the data indicating the position of the boundary between the part of the sensor that can receive light and the part that cannot receive light.

[0013] The output means may output data indicating the position of a boundary at one end in the arrangement direction of the plurality of light receiving units, among the boundaries between the portions of the sensor that can receive light and the portions that cannot receive light, to the external device (first configuration). The output means may also output data indicating the positions of a boundary at one end in the arrangement direction of the plurality of light receiving units, and a boundary at the other end in the arrangement direction, among the boundaries between the portions of the sensor that can receive light and the portions that cannot receive light, to the external device (second configuration). The arrangement direction of the plurality of light receiving units is, for example, a linear direction such as the up-down direction. The arrangement direction may be curved.

[0014] In this way, the amount of data output to the external device can be further reduced. The external device cannot grasp holes provided in an object passing between the multiple light-projecting units and the multiple light-receiving units, but can grasp the outer shape of the object. In the first configuration, for example, the position of the lower end of the sensor is regarded as the position of the lower end of the transported object, and the position of the boundary of the upper end is regarded as the position of the upper end of the transported object, thereby making it possible to grasp the outer shape of the transported object. Conversely, the position of the upper end of the sensor may be regarded as the position of the upper end of the transported object, and the position of the boundary of the lower end may be regarded as the position of the lower end of the transported object.

[0015] A second aspect of the present invention provides an input / output device that acquires the light reception results of a sensor having a plurality of light receiving parts that respectively receive light emitted from a plurality of light emitting parts and outputs the acquired results to an external device, wherein communication between the input / output device and the external device has a smaller maximum amount of data that can be transmitted per unit time than communication between the input / output device and the sensor, and the input / output device has an acquisition means for acquiring the light reception results, an analysis means for analyzing the light reception results and detecting the number of light receiving parts that were unable to receive light, and an output means for outputting data indicating the number detected by the analysis means to the external device.

[0016] If the number of light receiving sections that could not receive the light is known, the number of light passing between the multiple light transmitting sections and the multiple light receiving sections can be calculated. Here, we consider a case where an object being transported horizontally is detected by multiple light receiving units arranged vertically (up and down). In that case, the number of light receiving units that could not receive light is considered to be the height of the transported object, and the external shape of the transported object can be grasped.

[0017] According to the above-mentioned configuration, data indicating the number of light receiving sections that could not receive light is output to the external device instead of the light receiving result of the sensor. In this way, the amount of data output to the external device can be reduced compared to when the light receiving result of the sensor is output to the external device as it is. In addition, the external device can grasp the outline of an object passing between the multiple light projecting sections and the multiple light receiving sections.

[0018] A third aspect of the present invention provides an input / output device that acquires the light reception results of a sensor having a plurality of light receiving units that each receive light emitted from a plurality of light emitting units, and outputs the light reception results to an external device, wherein communication between the input / output device and the external device has a smaller maximum amount of data that can be transmitted per unit time than communication between the input / output device and the sensor, and the input / output device has an acquisition means for acquiring the light reception results, an analysis means for analyzing the light reception results and determining whether light was received for each of a plurality of groups into which the plurality of light receiving units are classified, the plurality of light receiving units being smaller than the plurality of light receiving units, and an output means for outputting data indicating whether light was received for each of the plurality of groups to the external device.

[0019] According to the above-mentioned configuration, data indicating whether or not light was received for each of a plurality of groups, which is less than the plurality of light receiving units, is output to the external device instead of the light receiving result of the sensor. This makes it possible to reduce the amount of data output to the external device compared to the case where the light receiving result of the sensor is output to the external device as is. In addition, the external device can grasp the outer shape of an object passing between the plurality of light projecting units and the plurality of light receiving units. The light from the plurality of light projecting units is basically blocked by the object, but if the object has a hole, the light reaches the group (light receiving unit) through the hole. Therefore, the external device can also grasp the hole provided in the object from the data indicating whether or not light was received for each of the plurality of groups.

[0020] In a third aspect, the analysis means may determine that light was received for a group that does not include a light receiving unit that was unable to receive light, and determine that light was not received for a group that includes a light receiving unit that was unable to receive light. In this way, the external device can grasp the outer shape of the object in a larger scale. In addition, various processes based on the size of the object can be suitably performed. For example, when detecting the passage of an object larger than a predetermined size as an abnormality, it is possible to prevent an abnormality from being overlooked.

[0021] The acquiring means may acquire the light reception results of a plurality of sensors, and the analyzing means may analyze the light reception results of the plurality of sensors by regarding the plurality of sensors as one sensor. In this way, when the number of sensors increases, an increase in the amount of data output to an external device can be suppressed.

[0022] The acquisition means may acquire light reception results of a plurality of sensors, and the output means may switch between the plurality of sensors and output data related to the target sensor. In this way, more detailed data can be output to an external device than when the plurality of sensors are regarded as one sensor. The target sensor may be switched, for example, automatically or manually. Here, consider a case where the output means switches the target sensor in response to an instruction from a user, and the external device analyzes the acquired data and provides the analysis result to the user. In that case, the user can obtain the analysis result related to the desired sensor.

[0023] The output means further outputs data of a time corresponding to the light receiving result to the external device. In this way, the external device can manage the substitute data of the light reception result of the sensor in association with a time. The time corresponding to the light reception result of the sensor is, for example, the time when the input / output device acquires the light reception result of the sensor, or the time when the input / output device outputs data to the external device.

[0024] The present invention can be understood as a sensing system having at least a part of the above configuration or function. The present invention can also be understood as a control method for an input / output device or a control method for a sensing system, including at least a part of the above processing, a program for causing a computer to execute these methods, or a computer-readable recording medium on which such a program is non-temporarily recorded. The above configurations and processing can be combined with each other to constitute the present invention as long as no technical contradiction occurs. Effect of the Invention

[0025] According to the present invention, the light reception results of the sensor can be output to an external device with a reduced amount of data while maintaining the characteristics of the sensor. [Brief description of the drawings]

[0026] [Figure 1]FIG. 1A is a schematic diagram showing a general configuration example of a sensing system to which the present invention is applied, and FIG. 1B is a block diagram showing the configuration example of a sensing system to which the present invention is applied. [Diagram 2] FIG. 2 is a flowchart illustrating an example of a processing flow of the input / output device according to the first embodiment. [Diagram 3] 3A and 3B are schematic diagrams showing an example of a method for transporting an object. [Figure 4] FIG. 4A is a schematic diagram showing an example of the position of the lowermost light receiving portion among the light receiving portions that were unable to receive light, and FIG. 4B is a schematic diagram showing an example of the position of the uppermost light receiving portion among the light receiving portions that were unable to receive light. [Diagram 5] FIG. 5A is a schematic diagram showing an example in which the outer shape of an object can be grasped from the positions of the lowermost light receiving section and the uppermost light receiving section of light receiving section 21 that were unable to receive light, and FIG. 5B is a schematic diagram showing an example in which the outer shape of an object can be grasped from the position of the uppermost light receiving section of light receiving section 21 that were unable to receive light. [Figure 6] FIG. 6 is a flowchart illustrating an example of a processing flow of the input / output device according to the second embodiment. [Figure 7] FIG. 7A is a schematic diagram showing an example in which the number of light receiving sections that are unable to receive light corresponds to the width of the object in the vertical direction, and FIG. 7B is a schematic diagram showing an example in which the outer shape of the object can be determined from the number of light receiving sections that are unable to receive light. [Figure 8] FIG. 8 is a flowchart illustrating an example of a processing flow of the input / output device according to the third embodiment. [Figure 9] FIG. 9A is a schematic diagram showing an example of the light receiving results (whether or not light was received) of a plurality of light receiving sections, and FIG. 9B is a schematic diagram showing an example of the judgment results (whether or not light was received) of a plurality of groups. [Figure 10] FIG. 10 is a schematic diagram showing an example of regarding a plurality of light receivers as one light receiver. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] <Application Examples> An application example of the present invention will be described.

[0028] 1A is a schematic diagram showing an example of the general configuration of a sensing system to which the present invention is applied. The sensing system includes a light projector 10, a light receiver 20 (sensor), an input / output device 100, and an external device 30. The light projector 10 includes a plurality of light projecting units 11, and the light receiver 20 includes a plurality of 1A is a system for detecting an intrusion of a worker into a hazardous area or the passage of a transported object, and the light projector 10 and the light receiver 20 are part of a safety light curtain.

[0029] The light receiving sections 21 face the light projecting sections 11, respectively, and receive the light emitted from the light projecting sections 11. The arrangement direction of the light projecting sections 11 and the light receiving sections 21 is not particularly limited, but is an up-down (vertical) direction in Fig. 1A. The arrangement direction may be a straight line such as the up-down direction, or may be curved.

[0030] The input / output device 100 acquires the light reception results of the light receiver 20 (plurality of light receiving sections 21) and outputs them to the external device 30. The light reception results of the light receiver 20 are, for example, data indicating the amount of light received for each light receiving section 21, data indicating whether or not light was received for each light receiving section 21, etc. The input / output device 100 may be configured integrally with the light receiver 20, or may be a device separate from the light receiver 20.

[0031] The external device 30 performs processing based on data (the light receiving result of the light receiver 20) from the input / output device 100. The external device 30 is not particularly limited, but is, for example, a PLC (Programmable Logic Controller).

[0032] Here, it is assumed that the maximum amount of data that can be transmitted per unit time in the communication between the input / output device 100 and the external device 30 is smaller than that in the communication between the input / output device 100 and the optical receiver 20. The communication between the input / output device 100 and the external device 30 is, for example, communication that complies with a standard such as IO-Link or Bluetooth.

[0033] In addition, there are many light receiving units 21 (and light projecting units 11), and the amount of data of the light receiving results of the multiple light receiving units 21 is also large. As described above, the maximum amount of data that can be transmitted per unit time between the input / output device 100 and the external device 30 is small. Therefore, the speed of the transmission path between the input / output device 100 and the external device 30 becomes a bottleneck, and there are cases where the data of the light receiving results taken into the input / output device 100 from the light receiver 20 cannot be transmitted to the external device 30 in a timely manner. In such a case, the external device 30 cannot reflect the light receiving results in the processing in real time.

[0034] Here, consider a case where the number of light receiving units 21 is 200, the light receiving result of each light receiving unit 21 is 1 byte, and the maximum amount of data that can be transmitted in one cycle between the input / output device 100 and the external device 30 is 32 bytes. In this case, the light receiving results of all the light receiving units 21 are 200 bytes of data, and seven cycles of transmission are required.

[0035] There is a conventional technology that stores an evaluation result as to whether or not the light receiving result of the light receiver 20 (light receiving results of the multiple light receiving sections 21) satisfies a predetermined standard, but the evaluation result is data on whether or not the predetermined standard is satisfied, that is, binary data. Therefore, if this evaluation result is output to the external device 30 instead of the light receiving result of the light receiver 20, the accuracy of the processing performed by the external device 30 (processing based on the light receiving result of the light receiver 20) will be significantly reduced.

[0036] Fig. 1B is a block diagram showing a configuration example of a sensing system to which the present invention is applied. Fig. 1B shows a configuration example of an input / output device 100. The input / output device 100 has an acquisition unit 101, an analysis unit 102, and an output unit 103. For example, the acquisition unit 101 is an input terminal or the like, the analysis unit 102 is a processor or the like, and the output unit 103 is an output terminal or the like.

[0037] The acquisition unit 101 acquires the light reception result of the light receiver 20. The analysis unit 102 analyzes the light reception result acquired by the acquisition unit 101. The output unit 103 outputs the light reception result acquired by the acquisition unit 101. Instead of the light result, the analysis result of the analysis unit 102 is output to the external device 30. The acquisition unit 101 is an example of an acquisition means, the analysis unit 102 is an example of an analysis means, and the output unit 103 is an example of an output means.

[0038] Although details will be described in each embodiment, the analysis unit 102 analyzes the light reception result of the light receiver 20 so that the amount of data can be reduced while maintaining the characteristics of the light reception result and output to the external device 30. By reducing the amount of data, the external device 30 can obtain substitute data for the light reception result of the light receiver 20 in a short time. Furthermore, by maintaining the characteristics of the light reception result of the light receiver 20, it is possible to obtain, as the processing result of the external device 30, a processing result equivalent to the processing result when the light reception result of the light receiver 20 is used.

[0039] <Embodiment 1> A first embodiment of the present invention will be described below. In the first embodiment, a sensing system has a configuration shown in Figures 1A and 1B.

[0040] In the first embodiment, the analysis unit 102 analyzes the light receiving result of the light receiver 20 to detect the boundary between the part of the light receiver 20 that can receive light and the part that cannot receive light. Then, the output unit 103 outputs data indicating the position of the boundary detected by the analysis unit 102 to the external device 30, instead of the light receiving result of the light receiver 20. The part of the light receiver 20 that can receive light is, for example, a part where the amount of received light is equal to or greater than a threshold. The part of the light receiver 20 that cannot receive light is, for example, a part where the amount of received light is less than a threshold. The position of the boundary between the part of the light receiver 20 that can receive light and the part that cannot receive light is, for example, the middle position between two light receiving units 21 adjacent to each other on either side of the boundary (the light receiving unit 21 that can receive light and the light receiving unit 21 that cannot receive light), or the position of one of the two light receiving units 21.

[0041] Generally, the data size is reduced by reducing the number of values ​​indicated by the data. Therefore, the size of the data indicating the position of the boundary between the part of the optical receiver 20 that can receive light and the part that cannot receive light is smaller than the light reception result of the optical receiver 20 (light reception result of the multiple light receiving units 21). In other words, according to the above-mentioned configuration, the amount of data output to the external device 30 can be reduced compared to the case where the light reception result of the optical receiver 20 (light reception result of the multiple light receiving units 21) is output to the external device 30 as it is.

[0042] Furthermore, if the position of the boundary between the part of the receiver 20 that can receive light and the part that cannot receive light is known, it is possible to grasp the external shape of an object passing between the transmitter 10 and the receiver 20 (details will be described later). In other words, according to the above-mentioned configuration, the external device 30 can grasp the external shape of an object passing between the transmitter 10 and the receiver 20.

[0043] Fig. 2 is a flowchart showing an example of a processing flow of the input / output device 100. In the processing flow of Fig. 2, of two light receiving sections 21 (light receiving section 21 that could receive light and light receiving section 21 that could not receive light) adjacent to each other across the boundary between the part of the light receiver 20 that could receive light and the part that could not receive light, the position of the light receiving section 21 that could not receive light is set as the position of the boundary. Then, data indicating the positions of the boundary at one end of the arrangement direction of the multiple light receiving sections 21 and the boundary at the other end of the arrangement direction among the boundaries between the part of the light receiver 20 that could receive light and the part that could not receive light is output to the external device 30 instead of the light reception result of the light receiver 20.

[0044] First, the acquiring unit 101 acquires the light receiving result of the light receiver 20 (light receiving results of the multiple light receiving units 21) from the light receiver 20 (step S201).

[0045] Next, the analysis unit 102 selects the lowermost light receiving unit 21 from among the multiple light receiving units 21 (step S202).

[0046] Next, the analysis unit 102 determines whether the amount of light received by the selected light receiving unit 21 is less than a predetermined threshold (step S203). The amount of light received can be determined from the light receiving result acquired in step S201. If it is determined that the amount of light received is less than the predetermined threshold (step S203: YES), the process proceeds to step S205, and if it is determined that the amount of light received is equal to or greater than the predetermined threshold (step S203: NO), the process proceeds to step S204.

[0047] In step S204, the analysis unit 102 determines whether the selected light receiving unit 21 is the uppermost light receiving unit 21. If it is determined that the selected light receiving unit 21 is the uppermost light receiving unit 21 (step S204: YES), this processing flow is terminated, and if it is determined that the selected light receiving unit 21 is not the uppermost light receiving unit 21 (step S204: NO), the processing proceeds to step S205. Note that if it is determined that the selected light receiving unit 21 is the uppermost light receiving unit 21 (step S204: YES), the output unit 103 may notify the external device 30 that there is no light receiving unit 21 that could not receive light (all light receiving units 21 are receiving light).

[0048] In step S205, the analysis unit 102 selects the light receiving unit 21 immediately above the currently selected light receiving unit 21 (switching the currently selected light receiving unit 21). Then, the process returns to step S203. That is, the light receiving units 21 are selected one by one from bottom to top until a light receiving unit 21 having an amount of received light less than a predetermined threshold is selected.

[0049] In step S206, the analysis unit 102 determines the currently selected light receiving unit 21 as the first light receiving unit, which is the light receiving unit 21 at the bottom end among the light receiving units 21 that were unable to receive light.

[0050] Next, the analysis unit 102 selects the uppermost light receiving unit 21 from among the multiple light receiving units 21 (step S207; switching of the selected light receiving unit 21).

[0051] Next, the analysis unit 102 determines whether the amount of light received by the selected light receiving unit 21 is less than a predetermined threshold (step S208). If it is determined that the amount of light received is less than the predetermined threshold (step S208: YES), the process proceeds to step S210, and if it is determined that the amount of light received is equal to or greater than the predetermined threshold (step S208: NO), the process proceeds to step S209.

[0052] In step S209, the analysis unit 102 selects the light receiving unit 21 immediately below the currently selected light receiving unit 21 (switching the currently selected light receiving unit 21). Then, the process returns to step S208. That is, the light receiving units 21 are selected one by one from top to bottom until a light receiving unit 21 having an amount of received light less than a predetermined threshold is selected.

[0053] In step S210, the analysis unit 102 determines the currently selected light receiving unit 21 as the second light receiving unit, which is the uppermost light receiving unit 21 among the light receiving units 21 that were unable to receive light.

[0054] Next, the output unit 103 outputs the position of the first light receiving unit determined in step S206 and the position of the second light receiving unit determined in step S210 to the external device 30 (step S211).

[0055] Here, consider a case where there are 200 light receiving sections 21, the light receiving result of each light receiving section 21 is 1 byte, and the data indicating the position of each light receiving section 21 is 1 byte. In this case, the light receiving results of all the light receiving sections 21 will be 200 bytes of data, but the data indicating the positions of the two light receiving sections 21 will be only 2 bytes.

[0056] The input / output device 100 repeatedly executes the process flow of Fig. 2. The repetition period of the process flow of Fig. 2 is not particularly limited, but for example, the process flow of Fig. 2 is repeated with the same period as the light emission period of the projector 10.

[0057] Here, consider the case where an object (e.g., a car body) passes horizontally between projector 10 and receiver 20. For example, as shown in Fig. 3A, the object is transported by a belt conveyor. The direction and method of transporting the object are not particularly limited, and the object may be transported while suspended from above as shown in Fig. 3B.

[0058] In this case, the processes of steps S202 to S206 are repeated to detect multiple positions along the bottom surface of the object. Specifically, as shown in FIG. 4A, multiple positions (circles) from position 401 to position 402 are detected in order. The circle in FIG. 4A indicates the position of the first light receiving unit (the light receiving unit 21 at the bottom among the light receiving units 21 that were unable to receive light). Similarly, the processes of steps S207 to S210 are repeated to detect multiple positions along the top surface of the object. Specifically, as shown in FIG. 4B, multiple positions (circles) from position 411 to position 412 are detected in order. The circle in FIG. 4B indicates the position of the second light receiving unit (the light receiving unit 21 at the top among the light receiving units 21 that were unable to receive light).

[0059] Then, by repeating the process of step S211, the external device 30 repeatedly acquires the position of the first light receiving unit and the position of the second light receiving unit. Specifically, the external device 30 repeatedly acquires the combination of the position of the first light receiving unit (the position corresponding to the lower end of the object) and the position of the second light receiving unit (the position corresponding to the upper end of the object) from the combination of the position 401 and the position 411 to the combination of the position 402 and the position 412. FIG. 5A shows a plurality of positions (circles) acquired by the external device 30. As shown in FIG. 5A, the line connecting the plurality of positions (circles) well represents the outer shape of the object. Therefore, the external device 30 can grasp the outer shape of the object from the plurality of acquired positions.

[0060] As described above, according to the first embodiment, the boundary between the part of the receiver 20 that can receive light and the part that cannot receive light is detected. Then, data indicating the position of the detected boundary is output to the external device 30 instead of the light reception result of the receiver 20. Specifically, data indicating the positions of the boundary at one end in the arrangement direction of the multiple light receiving units 21 and the boundary at the other end in the arrangement direction among the boundaries between the part of the receiver 20 that can receive light and the part that cannot receive light is output to the external device 30 instead of the light reception result of the receiver 20. In this way, the amount of data output to the external device 30 can be reduced compared to the case where the light reception result of the receiver 20 (the light reception result of the multiple light receiving units 21) is output to the external device 30 as it is. In addition, the external device 30 can grasp the outer shape of an object passing between the projector 10 and the receiver 20.

[0061] Although an example in which the analysis unit 102 detects only boundaries output from the output unit 103 as data has been described, the analysis unit 102 may detect more boundaries than the boundaries output from the output unit 103 as data.

[0062] Also, although an example has been described in which data indicating the positions of two boundaries is output to the external device 30, data indicating the position of one boundary (a boundary at one end in the arrangement direction of the multiple light receiving sections 21 among the boundaries between the part of the light receiving section 20 that can receive light and the part that cannot receive light) may be output to the external device 30. The external device 30 can grasp the outline of an object passing between the projector 10 and the light receiving section 20 even from the position of the light receiving section 21 at one end of the light receiving sections 21 that cannot receive light.

[0063] For example, the position of the lowermost light receiving section 21 among all the light receiving sections 21 is regarded as the position of the lower end of the transported object, and the position of the uppermost light receiving section 21 among the light receiving sections 21 that could not receive light is regarded as the position of the upper end of the transported object, thereby making it possible to grasp the outer shape of the transported object (FIG. 5B). The position of the uppermost light receiving unit 21 among the light receiving units 21 may be regarded as the position of the upper end of the transported object, and the position of the lowermost light receiving unit 21 among the light receiving units 21 that were unable to receive light may be regarded as the position of the lower end of the transported object.

[0064] However, although the portion of the object's outline on one side can be accurately grasped from the position of the boundary at one end, the portion on the other side cannot be accurately grasped. By using the positions of the boundaries at one end and the other end, the outline of the object can be grasped more accurately.

[0065] Also, data indicating the positions of all boundaries may be output to the external device 30. The light from the multiple light projecting units 11 is basically blocked by an object, but if the object has a hole, the light passes through the hole and reaches the light receiving unit 21. Therefore, if data indicating the positions of all boundaries is output to the external device 30, the external device 30 can also grasp the holes formed in the object.

[0066] <Embodiment 2> A second embodiment of the present invention will now be described. In the second embodiment, a sensing system has the configuration shown in Figures 1A and 1B.

[0067] In the second embodiment, the analysis unit 102 analyzes the light receiving results of the receiver 20 to detect the number of light receiving units 21 that failed to receive light. Then, the output unit 103 outputs data indicating the number detected by the analysis unit 102 to the external device 30, instead of the light receiving results of the receiver 20. If the number of light receiving units 21 that failed to receive light is known, it is possible to grasp the external shape of an object passing between the projector 10 and the receiver 20 (details will be described later). In other words, according to the above-mentioned configuration, the external device 30 can grasp the external shape of an object passing between the projector 10 and the receiver 20.

[0068] FIG. 6 is a flowchart showing an example of a processing flow of the input / output device 100.

[0069] First, the analysis unit 102 initializes a count value C indicating the number of light-receiving units 21 that have failed to receive light to 0 (step S601).

[0070] Next, the acquiring unit 101 acquires the light receiving result of the light receiver 20 (light receiving results of the multiple light receiving units 21) from the light receiver 20 (step S602).

[0071] Next, the analysis unit 102 selects the lowermost light receiving unit 21 from among the multiple light receiving units 21 (step S603).

[0072] Next, the analysis unit 102 determines whether the amount of light received by the selected light receiving unit 21 is less than a predetermined threshold (step S604). If it is determined that the amount of light received is less than the predetermined threshold (step S604: YES), the process proceeds to step S605, and if it is determined that the amount of light received is equal to or greater than the predetermined threshold (step S604: NO), the process proceeds to step S606.

[0073] In step S605, the analysis unit 102 adds 1 to the count value C. Then, the process proceeds to step S606.

[0074] In step S606, the analysis unit 102 determines whether or not the selected light receiving unit 21 is the uppermost light receiving unit 21. If it is determined that the selected light receiving unit 21 is the uppermost light receiving unit 21 (step S606: YES), the process proceeds to step S608. If it is determined that the selected light receiving unit 21 is not the uppermost light receiving unit 21 (step S606: NO), the process proceeds to step S607.

[0075] In step S607, the analysis unit 102 selects the light receiving unit 21 one level above the currently selected light receiving unit 21 (switching the currently selected light receiving unit 21). Then, the process returns to step S604. That is, the processes of steps S604 and S605 are repeated while selecting the light receiving units 21 one by one from the bottom light receiving unit 21 to the top light receiving unit 21. As a result, the count value C indicates the total number of light receiving units 21 that could not receive light.

[0076] In step S608, the output unit 103 outputs the count value C (the total number of light receiving units 21 that failed to receive light) to the external device 30.

[0077] The input / output device 100 repeatedly executes the process flow of Fig. 6. The repetition period of the process flow of Fig. 6 is not particularly limited, but for example, the process flow of Fig. 6 is repeated with the same period as the light emission period of the projector 10.

[0078] Here, consider a case where an object (e.g., a car body) passes horizontally between the projector 10 and the receiver 20. In this case, the processes of steps S601 to S607 are repeated, and the number of light-receiving units 21 that fail to receive light is repeatedly detected while changing the horizontal position (position in the horizontal direction) of the corresponding object. As indicated by the arrow in Fig. 7A, the number (total number) of light-receiving units 21 that fail to receive light corresponds to the width of the object in the vertical direction.

[0079] Then, by repeating the process of step S608, the external device 30 repeatedly acquires the value of the number of light receiving units 21 that were unable to receive light. As shown in Fig. 7B, the number acquired by the external device 30 (the number of light receiving units 21 that were unable to receive light) is regarded as the height of the object, and a shape that is close to the outer shape of the object is obtained. Therefore, the external device 30 can grasp the outer shape of the transported object from the number of light receiving units 21 that were unable to receive light.

[0080] As described above, according to the second embodiment, data indicating the number of light-receiving sections 21 that were unable to receive light is output to the external device 30 instead of the light-receiving result of the receiver 20. This makes it possible to reduce the amount of data output to the external device 30 compared to when the light-receiving result of the receiver 20 (light-receiving results of the multiple light-receiving sections 21) is output directly to the external device 30. In addition, the external device 30 can grasp the outline of an object passing between the projector 10 and the receiver 20.

[0081] Of the light receiving sections 21 that were unable to receive light, the lowermost light receiving section 21 and the uppermost light receiving section 21 may be detected using the same method as in embodiment 1. Then, the interval between the detected light receiving sections 21 may be calculated as the number of light receiving sections 21 that were unable to receive light.

[0082] <Embodiment 3> A third embodiment of the present invention will now be described. In the third embodiment, a sensing system has the configuration shown in Figures 1A and 1B.

[0083] In the third embodiment, the analysis unit 102 analyzes the light receiving result of the light receiver 20, and judges whether or not light was received for each of a plurality of groups into which the plurality of light receiving units 21 are classified, the plurality of groups being fewer than the plurality of light receiving units 21. Then, the output unit 103 outputs to the external device 30, instead of the light receiving result of the light receiver 20, data indicating whether or not light was received for each of the plurality of groups.

[0084] FIG. 8 is a flowchart showing an example of a processing flow of the input / output device 100.

[0085] First, the acquiring unit 101 acquires the light receiving result of the light receiver 20 (light receiving results of the multiple light receiving units 21) from the light receiver 20 (step S801).

[0086] Next, the analysis unit 102 selects the bottom group from among the multiple groups (step S802).

[0087] Next, the analysis unit 102 judges whether the selected group includes a light receiving unit 21 that was unable to receive light, for example, a light receiving unit 21 whose amount of received light is less than a predetermined threshold (step S803). If it is judged that the selected group includes a light receiving unit 21 that was unable to receive light (step S803: YES), the process proceeds to step S805. If it is judged that the selected group does not include a light receiving unit 21 that was unable to receive light (step S803: NO), that is, if all the light receiving units 21 included in the group were able to receive light, the process proceeds to step S804.

[0088] In step S804, the analysis unit 102 determines the selected group as a light-receiving group that was able to receive light, and then the process proceeds to step S806.

[0089] In step S805, the analysis unit 102 determines the selected group as a non-light receiving group, which is a group that was not able to receive light, and then the process proceeds to step S806.

[0090] In step S806, the analysis unit 102 determines whether the selected group is the top group. If it is determined that the selected group is the top group (step S806: YES), the process proceeds to step S808. If it is determined that the selected group is not the top group (step S806: NO), the process proceeds to step S807.

[0091] In step S807, the analysis unit 102 selects the group immediately above the selected group (switching the selected group). Then, the process returns to step S803. That is, the processes of steps S803 to S805 are repeated while selecting groups one by one from the bottom group to the top group.

[0092] In step S808, the output unit 103 outputs data indicating the light receiving group and the non-light receiving group to the external device 30.

[0093] The input / output device 100 repeatedly executes the process flow of Fig. 8. The repetition period of the process flow of Fig. 8 is not particularly limited, but for example, the process flow of Fig. 8 is repeated with the same period as the light emission period of the projector 10.

[0094] Here, consider the case where an object (e.g., the body of a car) passes horizontally between the projector 10 and the receiver 20. In this case, the process of step S801 is repeated, and the light reception result of the receiver 20 is repeatedly acquired while changing the horizontal position of the corresponding object. FIG. 9A shows an example of the light reception result of the receiver 20. Multiple squares lined up vertically indicate the light reception result (light reception result of the multiple light receiving units 21) obtained in one process of step S801. White squares indicate that light was received, and gray squares indicate that light was not received. In FIG. 9A, the gray area clearly shows the outline of the object, but whether or not light was received is expressed in detail, resulting in a large amount of data.

[0095] Therefore, in the third embodiment, as shown in FIG. 9B, each time the light receiving result of the light receiver 20 (light receiving results of the multiple light receiving units 21) is obtained, the multiple light receiving units 21 are classified into multiple groups that are fewer than the multiple light receiving units 21, and it is determined whether or not light was received for each group. The number of light receiving units 21 included in one group is not particularly limited, but in FIG. 9B, one group is composed of three light receiving units 21. Including the light receiving unit 21. Since the number of groups is smaller than the number of light receiving units 21, the amount of data for each group is smaller than the amount of data for each light receiving unit 21. In FIG. 9B as well, the gray areas represent the outline of the object. Furthermore, the gray areas can also represent holes (e.g., window frames) provided in the object. Therefore, the external device 30 can grasp the silhouette (outline and holes) of the transported object from the data representing the light receiving groups and non-light receiving groups.

[0096] As described above, according to the third embodiment, instead of the light receiving result of the light receiver 20, data indicating whether or not light was received for each of a plurality of groups, which is less than the plurality of light receiving units 21, is output to the external device 30. This makes it possible to reduce the amount of data output to the external device 30 compared to the case where the light receiving result of the light receiver 20 (light receiving result of the plurality of light receiving units 21) is output to the external device 30 as is. In addition, the external device 30 can grasp the outer shape of an object passing between the light projector 10 and the light receiver 20. The light from the plurality of light projecting units 11 is basically blocked by the object, but if a hole is provided in the object, the light reaches the group (light receiving unit 21) through the hole. Therefore, the external device 30 can also grasp the hole provided in the object from the data indicating whether or not light was received for each of the plurality of groups.

[0097] Moreover, according to the third embodiment, a group that does not include a light receiving unit 21 that was unable to receive light is determined to have received light, and a group that includes a light receiving unit 21 that was unable to receive light is determined to have not received light. In this way, the external device 30 can grasp the outer shape of the object in a larger scale. In addition, various processes based on the size of the object can be suitably performed. For example, when detecting the passage of an object larger than a predetermined size as an abnormality, it is possible to prevent the abnormality from being overlooked.

[0098] The method of determining whether or not a group was able to receive light is not particularly limited. For example, if a group does not include a light receiving unit 21 that was able to receive light, that is, if all the light receiving units 21 included in the group were unable to receive light, the group may be determined to have been unable to receive light. On the other hand, if a group includes a light receiving unit 21 that was able to receive light, the group may be determined to have been able to receive light.

[0099] <Other> The above-described embodiment merely illustrates an exemplary configuration of the present invention. The present invention is not limited to the above-described specific embodiment, and various modifications are possible within the scope of the technical concept thereof.

[0100] 10, multiple optical receivers 20 may be connected for use (the number of optical receivers 20 is not particularly limited). In this case, the acquisition unit 101 acquires the light reception results of the multiple optical receivers 20. The analysis unit 102 may analyze the light reception results of the multiple optical receivers 20 by regarding the multiple optical receivers 20 as one optical receiver 1000. In this way, when the number of optical receivers 20 increases, an increase in the amount of data output to the external device 30 can be suppressed.

[0101] The output unit 103 may also switch between the multiple optical receivers 20 and output data related to the target optical receiver 20. This allows more detailed data to be output to the external device 30 than when the multiple optical receivers 20 are considered as one sensor. At this time, the analysis unit 102 may or may not analyze only the light reception result of the target optical receiver 20. The target optical receiver 20 may be switched automatically or manually, for example. Here, consider a case where the output unit 103 switches the target optical receiver 20 in response to an instruction from a user, and the external device 30 analyzes the acquired data and provides the analysis result to the user. In that case, the user can obtain the analysis result related to the desired optical receiver 20.

[0102] The output unit 103 may further output data of a time corresponding to the light reception result of the light receiver 20 to the external device 30. In this way, the external device 30 can manage the alternative data of the light reception result of the light receiver 20 in association with the time, and can provide more suitable information to the user. The time corresponding to the light reception result of the light receiver 20 is, for example, the time when the input / output device 100 acquires the light reception result of the light receiver 20, the time when the input / output device 100 outputs data to the external device 30, etc.

[0103] <Appendix 1> An input / output device (100) that acquires a light receiving result of a sensor (20) having a plurality of light receiving sections (21) that respectively receive light emitted from a plurality of light emitting sections (11) and outputs the light receiving result to an external device (30), In the communication between the input / output device (100) and the external device (30), the maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device (100) and the sensor (20); The input / output device (100) includes: An acquisition means (101) for acquiring the light receiving result; an analysis means (102) for analyzing the light reception result and detecting a boundary between a portion of the sensor (20) which can receive light and a portion of the sensor (20) which cannot receive light; an output means (103) for outputting data indicating the position of the boundary detected by the analysis means (102) to the external device (30); have An input / output device (100).

[0104] <Appendix 2> An input / output device (100) that acquires a light receiving result of a sensor (20) having a plurality of light receiving sections (21) that respectively receive light emitted from a plurality of light emitting sections (11) and outputs the light receiving result to an external device (30), In the communication between the input / output device (100) and the external device (30), the maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device (100) and the sensor (20); The input / output device (100) includes: An acquisition means (101) for acquiring the light receiving result; an analysis means (102) for analyzing the light receiving results and detecting the number of light receiving sections (21) that were unable to receive light; an output means (103) for outputting data indicating the number detected by the analysis means (102) to the external device (30); have An input / output device (100).

[0105] <Appendix 3> An input / output device (100) that acquires a light receiving result of a sensor (20) having a plurality of light receiving sections (21) that respectively receive light emitted from a plurality of light emitting sections (11) and outputs the light receiving result to an external device (30), In the communication between the input / output device (100) and the external device (30), the maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device (100) and the sensor (20); The input / output device (100) includes: An acquisition means (101) for acquiring the light receiving result; The light receiving results are analyzed, and it is determined whether or not light was received for each of a plurality of groups into which the plurality of light receiving sections (21) are classified, the number of groups being smaller than the number of the light receiving sections (21). Analysis means (102); an output means (103) for outputting data indicating whether or not light was received for each of the plurality of groups to the external device (30); have An input / output device (100).

[0106] <Appendix 4> A method for controlling an input / output device (100) that acquires a light reception result of a sensor (20) having a plurality of light receiving units (21) that respectively receive light emitted from a plurality of light emitting units (11) and outputs the light reception result to an external device (30), comprising: In the communication between the input / output device (100) and the external device (30), the maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device (100) and the sensor (20); The control method includes: An acquisition step (S201) of acquiring the light receiving result; an analysis step (S202 to S210) of analyzing the light reception result and detecting a boundary between a portion of the sensor (20) that can receive light and a portion of the sensor (20) that cannot receive light; an output step (S211) of outputting data indicating the positions of the boundaries detected in the analysis steps (S202 to S210) to the external device (30); have A control method comprising:

[0107] <Appendix 5> A method for controlling an input / output device (100) that acquires a light reception result of a sensor (20) having a plurality of light receiving units (21) that respectively receive light emitted from a plurality of light emitting units (11) and outputs the light reception result to an external device (30), comprising: In the communication between the input / output device (100) and the external device (30), the maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device (100) and the sensor (20); The control method includes: An acquisition step (S602) of acquiring the light receiving result; an analysis step (S603 to S607) of analyzing the light receiving result and detecting the number of light receiving parts (21) that could not receive light; an output step (S608) of outputting data indicating the number detected in the analysis steps (S603 to S607) to the external device (30); have A control method comprising:

[0108] <Appendix 6> A method for controlling an input / output device (100) that acquires a light reception result of a sensor (20) having a plurality of light receiving units (21) that respectively receive light emitted from a plurality of light emitting units (11) and outputs the light reception result to an external device (30), comprising: In the communication between the input / output device (100) and the external device (30), the maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device (100) and the sensor (20); The control method includes: An acquisition step (S801) of acquiring the light receiving result; an analysis step (S802 to S807) of analyzing the light receiving results and determining whether or not light was received for each of a plurality of groups into which the plurality of light receiving units are classified, the number of groups being smaller than the plurality of light receiving units; an output step (S808) of outputting data indicating whether or not light was received for each of the plurality of groups to the external device (30); have A control method comprising: [Explanation of symbols]

[0109] 100: Input / output device 101: Acquisition unit 102: Analysis unit 103: Output unit 10: Emitter 11: Emitter section 20,1000: Receiver 21: Receiver section 30: External device

Claims

1. An input / output device that acquires a light receiving result of a sensor having a plurality of light receiving units that respectively receive light emitted from a plurality of light emitting units, and outputs the light receiving result to an external device, In the communication between the input / output device and the external device, a maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device and the sensor; The input / output device is An acquisition means for acquiring the light receiving result; an analysis means for analyzing the light reception result and detecting a boundary between a portion of the sensor which can receive light and a portion which cannot receive light; an output means for outputting data indicating the position of the boundary detected by the analysis means to the external device; have 1. An input / output device comprising:

2. The output means outputs data indicating a position of a boundary at one end in an arrangement direction of the plurality of light receiving sections, among boundaries between a portion of the sensor that can receive light and a portion that cannot receive light, to the external device.

2. The input / output device according to claim 1 .

3. The output means outputs data indicating the positions of a boundary at one end in an arrangement direction of the plurality of light receiving units and a boundary at the other end in the arrangement direction, among the boundaries between the light receiving portion and the light not receiving portion of the sensor, to the external device.

2. The input / output device according to claim 1 .

4. An input / output device that acquires a light receiving result of a sensor having a plurality of light receiving units that respectively receive light emitted from a plurality of light emitting units, and outputs the light receiving result to an external device, In the communication between the input / output device and the external device, a maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device and the sensor; The input / output device is An acquisition means for acquiring the light receiving result; an analysis means for analyzing the light receiving result and detecting the number of light receiving parts that could not receive light; and an output means for outputting data indicating the number detected by the analysis means to the external device.

1. An input / output device comprising:

5. An input / output device that acquires a light receiving result of a sensor having a plurality of light receiving units that respectively receive light emitted from a plurality of light emitting units, and outputs the light receiving result to an external device, In the communication between the input / output device and the external device, a maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device and the sensor; The input / output device is An acquisition means for acquiring the light receiving result; an analysis means for analyzing the light receiving results and determining whether light was received for each of a plurality of groups into which the plurality of light receiving units are classified, the number of groups being smaller than the plurality of light receiving units; an output means for outputting data indicating whether or not light was received for each of the plurality of groups to the external device; have 1. An input / output device comprising:

6. The analysis means For groups that do not include light receiving units that were not able to receive light, it is determined that light was received. It is determined that the group including the light receiving unit that could not receive light was unable to receive light.

6. The input / output device according to claim 5.

7. The acquiring means acquires light reception results of a plurality of sensors, The analyzing means regards the plurality of sensors as one sensor and analyzes the light receiving results of the plurality of sensors.

7. The input / output device according to claim 1, wherein the input / output device is a first input / output device.

8. The acquiring means acquires light reception results of a plurality of sensors, The output means switches between the plurality of sensors and outputs data related to the sensor of the switch.

8. The input / output device according to claim 1, wherein the input / output device is a first input / output device.

9. The output means further outputs data of a time corresponding to the light receiving result to the external device.

9. The input / output device according to claim 1, wherein the input / output device is a first input / output device.

10. A method for controlling an input / output device that acquires a light receiving result of a sensor having a plurality of light receiving units that respectively receive light emitted from a plurality of light emitting units, and outputs the light receiving result to an external device, comprising: In the communication between the input / output device and the external device, a maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device and the sensor; The control method includes: an acquisition step of acquiring the light receiving result; an analysis step of analyzing the light reception result to detect a boundary between a portion of the sensor that can receive light and a portion of the sensor that cannot receive light; an output step of outputting data indicating the position of the boundary detected in the analysis step to the external device; have A control method comprising:

11. A method for controlling an input / output device that acquires a light receiving result of a sensor having a plurality of light receiving units that respectively receive light emitted from a plurality of light emitting units, and outputs the light receiving result to an external device, comprising: In the communication between the input / output device and the external device, a maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device and the sensor; The control method includes: an acquisition step of acquiring the light receiving result; an analysis step of analyzing the light receiving result to detect the number of light receiving parts that could not receive light; an output step of outputting data indicating the number detected in the analysis step to the external device; have A control method comprising:

12. A method for controlling an input / output device that acquires a light receiving result of a sensor having a plurality of light receiving units that respectively receive light emitted from a plurality of light emitting units, and outputs the light receiving result to an external device, comprising: In the communication between the input / output device and the external device, a maximum amount of data that can be transmitted per unit time is smaller than that in the communication between the input / output device and the sensor; The control method includes: an acquisition step of acquiring the light receiving result; The light receiving results are analyzed, and the plurality of light receiving units are classified. an analysis step of determining whether or not light was received for each of a plurality of groups that are not included in the group; an output step of outputting data indicating whether or not light was received for each of the plurality of groups to the external device; have A control method comprising:

13. A program for causing a computer to execute each step of the control method according to any one of claims 10 to 12.

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