Measuring device, measuring system and moving body operation method

Abstract

The measuring device, measuring system and moving body operation method of the present invention measure the absolute position of a moving object on a moving path at high speed and high precision. The measuring system includes: a light transmitting unit that responds to a selection signal to transmit light to illuminate a stationary structure in the moving path; an imaging unit that images scattered light from the stationary structure on a photographing surface; a photographing unit that obtains the light signal imaged on the photographing surface and converts it into an electrical signal; an image processing unit that calculates information related to the absolute position of the moving body (car) based on a photographed image generated from the electrical signal converted by the photographing unit, the image processing unit performs a mark recognition process that determines a reference line representing the absolute position of the mark using light and dark brightness changes in a second direction perpendicular to the first direction in the photographed image when the image of the mark is included in the photographed image, and a movement amount calculation process that calculates the movement amount of the moving body from the reference line determined by the mark recognition process.

Description

Technical Field

[0001] The present invention relates to a measuring device, a measuring system and a moving body operation method, and is preferably applicable to a measuring device, a measuring system and a moving body operation method for calculating information related to the movement of a moving body such as an elevator car. Background Art

[0002] Conventionally, in an elevator having a car as a moving body (hereinafter referred to as "elevator car" or "car"), a speed governor rope is used as a safety device for monitoring the position of the elevator car, the moving speed of the elevator car, and the like.

[0003] In recent years, there has been known a sensor that measures the position and moving speed of an elevator car in a non-contact manner instead of a speed governor rope (hereinafter referred to as a "position moving speed sensor"). For example, Patent Document 1 discloses an optical position moving speed sensor that measures the position and moving speed of the elevator car by photographing a structure in a shaft using an image sensor provided on the elevator car. In a non-contact position moving speed sensor, since a long strip-shaped structure such as a speed governor rope is not required, the installation and maintenance properties are improved, and measurement errors due to slipping are not generated.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: International Publication No. 2019-239536 Summary of the invention

[0007] Technical problem to be solved by the invention

[0008] However, when the elevator car is running, the measuring device for detecting the position and moving speed of the elevator car needs to detect the situation that the car is safely parked in the door area in the hoistway, and control so that the door opening and closing device does not operate when it is outside the door area. However, the above-mentioned existing optical position movement speed sensor measures the moving distance relatively based on the time difference of the image of the structure captured by the image sensor, and can only detect the reference position by combining with other independent structures. Therefore, there is the following problem: it is difficult to measure the absolute position of the reference position set in the hoistway at high speed and high precision from the high-speed moving elevator car.

[0009] The present invention is completed in consideration of the above contents, and proposes a measuring device, a measuring system and a moving body operation method, which can measure the absolute position of the moving body on the moving path at high speed and high precision.

[0010] Technical means for solving technical problems

[0011] In order to solve the above-mentioned problems, the present invention provides a measuring device, which is arranged on a moving body moving on a moving path and measures the position of the moving body, and the measuring device includes: a light transmitting unit, which, in response to a selection signal generated at a specified period, transmits light for irradiating a stationary structure arranged on the moving path along a first direction parallel to the moving direction of the moving body; an imaging unit, which images the scattered light from the stationary structure generated by the light on a shooting surface; a shooting unit, which acquires the optical signal of the scattered light imaged on the shooting surface within an exposure time specified by the selection signal and converts it into an electrical signal; and an image processing unit, which The selection signal is generated at the specified period, and image processing is performed on the electrical signal obtained after conversion by the imaging unit to generate a captured image, and information related to the absolute position of the moving body is calculated based on the captured image. The image acquisition unit includes: a mark recognition process, in which, when the captured image includes an image of a mark set on the stationary structure, a baseline representing the reference of the absolute position of the mark is determined by utilizing the brightness changes in the captured image in a second direction perpendicular to the first direction; and a movement amount calculation process, in which the movement amount of the moving body starting from the baseline determined by the mark recognition process is calculated.

[0012] In addition, in order to solve the above-mentioned problem, the present invention provides a measuring system for measuring the position of a moving body moving on a moving path, the measuring system comprising: a measuring device, the measuring device being arranged on the moving body; and a marker, the marker being arranged on a stationary structure arranged on the moving path along a first direction parallel to the moving direction of the moving body, and at least one marker being arranged at regular intervals along the first direction. In the measuring system, the measuring device comprises: a light transmitting unit, the light transmitting unit transmitting light for irradiating a stationary structure arranged on the moving path along a first direction parallel to the moving direction of the moving body in response to a selection signal generated at a specified period; an imaging unit, the imaging unit imaging the scattered light from the stationary structure generated by the light on a shooting surface; a shooting unit, the shooting unit acquiring a light signal of the scattered light imaged on the shooting surface within an exposure time specified by the selection signal and converting it into an electrical signal; and an image processing unit, the image processing unit generating the selection signal at the specified period and Image processing is performed on the electrical signal converted by the imaging unit to generate a captured image, and information related to the absolute position of the moving body is calculated based on the captured image. The image processing unit includes: a mark recognition process, in which, when an image of any one of the marks is included in the captured image, a baseline representing the absolute position of the mark is determined by using changes in light and dark brightness in a second direction perpendicular to the first direction in the captured image; and a movement amount calculation process, in which the movement amount of the moving body starting from the baseline determined by the mark recognition process is calculated.

[0013] In order to solve the above-mentioned problem, the present invention provides a moving body operation method as follows, which is performed by an elevator system to return an elevator car to a nearby floor. Here, the elevator system is configured to include: a marker, which is arranged on a stationary structure in a hoistway along a first direction parallel to the moving direction of the elevator car, and at least one marker is arranged between each floor along the first direction; a measuring device, which is arranged on the elevator car, photographs the stationary structure, and calculates the position information of the marker when the image of the marker is included in the photographed image; an elevator control unit, which controls the movement of the elevator car; and floor height information, which indicates the position information of the marker and the floor for the marker corresponding to each floor. Moreover, the moving body operation method includes: a first step in which the elevator control unit moves the elevator car to the nearby mark; a second step in which the measuring device calculates the position information of the mark based on the captured image of the mark at the moving destination of the first step; a third step in which the elevator control unit calculates the moving distance from the mark to the floor based on the position information of the mark calculated in the second step and the floor height table; and a fourth step in which the elevator control unit moves the elevator car the moving distance calculated in the third step.

[0014] Effects of the Invention

[0015] According to the present invention, the absolute position of a moving object on a moving path can be measured at high speed and with high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a diagram showing a configuration example of an elevator system 10 according to Embodiment 1 of the present invention.

[0017] Figure 2 1 is a diagram showing a configuration example of the measurement system 100 .

[0018] Figure 3 2 is a diagram showing an example of the internal configuration of the image processing unit 240 .

[0019] Figure 4 : is a flowchart showing an example of the processing procedure of the measurement processing by the image processing unit 240 .

[0020] Figure 5 It is a diagram for explaining changes in the captured image when the car 120 moves.

[0021] Figure 6 1 is a diagram showing an example of a timing chart of a strobe signal transmitted from the control section 310 to the imaging section 230 .

[0022] Figure 7is a diagram showing an example of brightness distribution of a captured image during exposure time.

[0023] Figure 8 is a diagram showing a specific example of the brightness mark 150 .

[0024] Fig. 9 1 is a diagram showing an example of the brightness distribution of a captured image of the brightness mark 151 .

[0025] Fig.10 It is a diagram for explaining the dimensional relationship between the brightness mark 150 and the imaging area of ​​the measurement device 110 .

[0026] Fig.11 This is a conceptual diagram for explaining the process of the return operation control of the elevator car 120.

[0027] Fig.12 This diagram shows a measurement device 1200 according to Embodiment 2 of the present invention, focusing on an example of the internal structure of an imaging unit 1220 .

[0028] Fig.13 This diagram shows a measurement device 1300 according to Embodiment 3 of the present invention, focusing on an example of the internal structure of an imaging unit 1320 .

[0029] Fig.14 This diagram shows a measurement device 1400 according to a fourth embodiment of the present invention, focusing on an example of the internal structure of an imaging unit 1420 .

[0030] Fig.15 This is a diagram showing a configuration example of a measurement system 1500 according to Embodiment 5 of the present invention.

[0031] Fig.16 1 is a diagram showing a configuration example of a vehicle positioning system 1600 in which the measurement device 110 is applied to a vehicle.

[0032] Fig.17 1 is a diagram showing a configuration example of a crane positioning system 1700 in which the measuring device 110 is applied to a crane. DETAILED DESCRIPTION

[0033] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In each embodiment of the present invention described in detail below, a device, system, and method are described, which use a measurement system including a measurement device provided on a moving body and a brightness mark arranged on a path (moving path) for guiding the moving body to identify a reference position provided on the path, and measure the absolute position of the moving body determined by the reference position at high speed and high precision. However, the present invention is not limited to each embodiment described below.

[0034] The measuring device shown in each embodiment is placed on the upper part of the moving body and measures information related to the movement of the moving body (specifically, the absolute position of the moving body, the moving speed of the moving body, the acceleration of the moving body, the vibration of the moving body, etc.). For example, the measuring device irradiates (transmits) light from the light transmitting unit of the moving body to the surface of the stationary structure as the photographed object in response to the selection signal generated in the control unit. Then, the measuring device causes the light (which can contain regular reflected light and diffuse reflected light, hereinafter referred to as "scattered light") bounced off the surface of the stationary structure to be incident on the photographing surface of the photographing unit via the imaging unit, and photoelectrically converts the light signal into an electrical signal in the photographing unit. Then, the measuring device measures information related to the reference position (specifically, the presence or absence of a brightness mark as a reference, the reference position of the brightness mark, and the ID for distinguishing the reference position assigned to each brightness mark, etc.) in the mark recognition unit based on the image generated from the electrical signal obtained after the conversion. Furthermore, the measuring device measures information related to the movement of the moving body (specifically, the moving distance from the reference position of the moving body, the moving speed of the moving body, the vibration of the moving body, etc.) in the image processing unit based on the image generated from the converted electrical signal. Then, the measuring device calculates information on the absolute position of the moving body on the moving path based on the information related to the reference position and the information related to the movement of the moving body, and sends the calculated information to the moving body control unit for controlling the operation of the moving body or the control of the safety device. Then, the moving body control unit controls the operation of the moving body and controls the safety device based on the information on the absolute position of the moving body calculated by the measuring device.

[0035] Furthermore, in certain embodiments, an elevator car is used as an example of a moving body provided with the measuring device of the present invention, but the moving body to which the present invention can be applied is not limited to the elevator car. The techniques shown in the various embodiments can also be applied to moving bodies (e.g., automatic doors, trains, vehicles, cranes, etc.) that move along stationary structures (e.g., guide rails, lines, roads, etc.) with artificially ground scratches. In addition, in this specification, "light" refers to electromagnetic waves, and specifically, in addition to visible light, it can also be microwaves, terahertz waves, infrared rays, ultraviolet rays, X-rays, etc. Similarly, the measuring system to which the present invention can be applied is not limited to the measuring system assembled into the elevator system, and can also be applied to, for example, the positioning system for controlling the automatic operation of the vehicle, the positioning system for the crane, etc.

[0036] In addition, in the following description, when describing the same kind of elements without distinguishing them, the common part (part other than the branch number) of the reference numeral including the branch number may be used, and when describing the same kind of elements with distinction, the reference numeral including the branch number may be used. For example, when describing the shooting area without distinguishing them, it is recorded as "brightness mark 150", while when describing the measurement parts (shooting areas) with distinction, it is recorded as "brightness mark 150-1" or "brightness mark 150-2".

[0037] (1) Implementation Method 1

[0038] (1-1) Structure of Elevator System 10

[0039] Figure 1 This is a diagram showing a configuration example of an elevator system 10 according to Embodiment 1 of the present invention.

[0040] like Figure 1 As shown, the elevator system 10 is configured to include a measuring system 100, and the measuring system 100 is configured to include a measuring device 110 mounted on the upper part of an elevator car 120, and the elevator car 120 is raised and lowered in a shaft (a moving path of a moving body) of a building (not shown); and a plurality of brightness marks 150 (individually, for example, brightness marks 150-1 and 150-2) provided to indicate a reference position in the shaft. In addition, as shown Figure 1 As shown, the elevator system 10 includes an elevator car 120 , an elevator control unit 130 , or a guide rail 140 , but at least any one of these components may be included in the measurement system 100 .

[0041] The measuring device 110 outputs signal information useful for controlling the operation of the elevator car 120 (for example, signal information related to the position, moving speed, acceleration, etc. of the elevator car 120) to the elevator control unit 130. The elevator control unit 130 controls the operation of the elevator car 120 and controls the safety device. The configuration position of the measuring device 110 is not limited to the upper part of the elevator car 120, and can also be configured at a position other than the upper part, such as the side part, the lower part, etc.

[0042] The guide rail 140 is an example of a stationary structure arranged in the hoistway, and is arranged along the moving direction ( Figure 1The guide rail 140 is arranged in the hoistway (in the y-axis direction) and contacts the guide roller (not shown) of the elevator car 120 to support the movement of the moving body (elevator car 120). In addition, the brightness marks 150 are arranged at predetermined intervals on the top or side of a certain surface of the guide rail 140 (for example, the sliding surface in contact with the guide roller), the flange surface fastened to the wall surface by the bolts of the guide rail 140, or the neck located at the boundary between the sliding surface and the flange surface.

[0043] For example, the brightness mark 150 is attached in the form of a sticker, but it can also be realized by processing the guide rail 140 through mechanical engraving or laser marking, which has strong resistance to interference such as stains or rust caused by aging. Alternatively, an indicator such as an LED pre-embedded in the guide rail 140 can be used for the brightness mark 150, which has high brightness and can be identified with a high S / N ratio.

[0044] Figure 2 1 is a diagram showing a configuration example of the measurement system 100. Figure 2 As shown in FIG. 1 , the measuring device 110 is configured to include a light transmitting unit 210, an imaging unit 220, a photographing unit 230, and an image processing unit 240. Figure 2 In the figure, the light path is shown by the dotted line with an arrow, and the path of the electrical signal is shown by the solid line with an arrow.

[0045] The light transmitting unit 210 includes a light source (not shown) and is configured to irradiate light to the guide rail 140 as a photographed object and the brightness mark 150 provided on the guide rail 140. The light source of the light transmitting unit 210 may be a temporally and spatially incoherent light source such as an LED (Light Emitting Diode) or a halogen lamp, or a temporally and spatially coherent light source such as a laser light source.

[0046] The imaging unit 220 is configured as an optical system that images scattered light on the imaging surface of the imaging unit 230. The scattered light is obtained by scattering the light irradiated from the light sending unit 210 toward the surface of the guide rail 140 or the brightness mark 150 of the guide rail 140, i.e., the outgoing light (outgoing light), by the surface of the guide rail 140 or the brightness mark 150.

[0047] The photographing unit 230 converts the optical signal from the imaging unit 220 (the optical signal representing the scattered brightness distribution on the surface of the guide rail 140 or the surface of the brightness mark 150), that is, the optical signal imaged on the photographing surface including a plurality of pixels (pixels), into an electrical signal corresponding to the brightness of the pixel, and sends the converted electrical signal to the image processing unit 240 as an image signal representing a dark field image. In addition, in the present embodiment, the image signal sent from the photographing unit 230 to the image processing unit 240 is not limited to representing a dark field image, but may also represent, for example, a bright field image. For example, a CCD (Charge Coupled Device) image sensor, a CMOS (Complementary Metal Oxide Semiconductor) image sensor, or the like may be used for the photographing unit 230. In addition, the photographing unit 230 may be a two-dimensional area sensor, or a one-dimensional line sensor having a spatial decomposition function in the lifting direction of the car 120.

[0048] In addition, the measuring system 100 may also provide a wavelength selective filter such as a bandpass filter outside the imaging unit 220 in the path of the outgoing light and the scattered light from the light transmitting unit 210 to remove external light other than the desired wavelength. In addition, in order to protect the measuring device 110, the measuring system 100 may provide a window material or the like in the path of the incident light and the scattered light so that sand, dust, etc. do not enter the measuring device 110.

[0049] The image processing unit 240 performs a predetermined image processing on the image signal (an electrical signal obtained by converting the optical signal formed on the imaging surface) received from the imaging unit 230, calculates information related to the movement of the elevator car 120 (car movement related information) and information related to the reference position of the brightness mark 150 (reference position related information) based on the captured image generated by the image processing, and sends the information to the elevator control unit 130. The image processing unit 240 may be composed of an information processing storage medium such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit) or a microcontroller, or may be composed of a logic circuit element such as an FPGA (Field-Programmable Gate Array).

[0050] (1-2) Configuration of the Image Processing Unit 240 and Measurement Processing by the Image Processing Unit 240

[0051] Next, the internal structure of the image processing unit 240 and the processing performed by the image processing unit 240 will be described in detail.

[0052] Figure 3 2 is a diagram showing an example of the internal structure of the image processing unit 240. Figure 3 As shown, the image processing unit 240 is configured to include a control unit 310 , a movement amount calculation unit 320 , a brightness mark recognition unit 330 , and a communication unit 340 .

[0053] The control unit 310 generates a plurality of strobe signals (strobe pulse signals), sends one of the generated strobe signals to the light transmitting unit 210, and sends another strobe signal to the imaging unit 230. The strobe signal sent to the light transmitting unit 210 is used as a timing signal that specifies the driving time of the light source in the light transmitting unit 210. The strobe signal sent to the imaging unit 230 is used as a timing signal that specifies the exposure time in the imaging unit 230. Then, the control unit 310 performs a prescribed image processing on the electrical signal from the imaging unit 230, and sends the image processed image to the movement amount calculation unit 320 and the brightness mark recognition unit 330. In addition, the image processing of the control unit 310 is specifically, for example, a process for spatially decomposing the electrical signal (for example, an image signal representing a dark field image) from the imaging unit 230 into an image corresponding to the scattered brightness distribution on the surface of the guide rail 140.

[0054] The movement amount calculation unit 320 calculates information related to the movement of the elevator car 120 (car movement related information) based on the image processing result received from the control unit 310, and sends the calculated signal information to the communication unit 340. Specifically, the car movement related information includes information indicating the position and movement speed of the car 120, for example.

[0055] The brightness mark recognition unit 330 performs image recognition processing for recognizing the brightness mark 150 on the image after image processing received from the control unit 310, calculates information related to the reference position of the brightness mark 150 (reference position associated information), and transmits the calculated signal information to the communication unit 340. Specifically, the reference position associated information includes, for example, information indicating the presence or absence of the brightness mark 150 as a reference, an ID (hereinafter described in detail as an "ID pattern") for identifying the reference position of the brightness mark 150 (the reference position assigned to each brightness mark 150), and the like.

[0056] The communication unit 340 converts the car movement related information received from the movement amount calculation unit 320 and the reference position related information received from the brightness mark recognition unit 330 according to a communication protocol receivable by the elevator control unit 130 (for example, a protocol of CAN (Controller Area Network) communication, etc.), and outputs the converted signal information to the elevator control unit 130.

[0057] Figure 4 : is a flowchart showing an example of the processing procedure of the measurement process performed by the image processing unit 240 .

[0058] according to Figure 4 , the image processing unit 240 starts the measurement based on the selection signal generated by the control unit 310, and the control unit 310 obtains the image I(i) sent from the shooting unit 230 through the electrical signal for each frame i (step S101). Frame i is preferably a time that is an integer multiple of the frame period Δt described later. In addition, as described above, the image I(i) is, for example, a dark field image. Then, in step S101, the control unit 310 stores the acquired image I(i) in a storage element (memory) within the control unit 310. The storage element for storing the image I(i) may use a volatile memory such as a register possessed by the image processing unit 240, or may use a non-volatile memory configured externally.

[0059] After the process of step S101, the processes of steps S102 to S104 and the process of step S105 are executed in parallel. In addition, as described later, in step S104, the process result of step S105 is used.

[0060] In steps S102 to S104, the movement amount calculation unit 320 calculates, for example, the position of the car 120 (the total movement amount of the car 120 from the reference position of the brightness mark 150) and the movement speed V of the car 120 as the car movement related information.

[0061] First, the movement amount calculation unit 320 reads the image I(i) of the i-th frame stored in the storage element from the storage element in step S101, and reads the image I(ik) of the ik-th frame stored in the storage element k frames before the i-th frame (k is an integer greater than 1) from the storage element, and calculates the movement amount Δy of the car 120 from the ik-th frame to the i-th frame based on the difference between the image I(i) and the image I(ik) (process S102).

[0062] The calculation of the movement amount Δy of the car 120 in step S102 will be described later. Figure 5 In the figure, more specific images are supplemented by showing examples of captured images.

[0063] In addition, in step S102, the method for selecting the image I(ik) that is the difference from the latest image I(i) may select an image i frames ago (k=1), or may select an image multiple frames ago (k=an integer greater than or equal to 2). In addition, in the method for calculating the movement amount Δy of the car 120, for example, the cross-correlation function, which is an indicator of the similarity between the image I(i) and the image I(ik), is calculated, and the y component of the peak coordinate position of the cross-correlation function (the component in the same direction as the lifting direction of the car 120) is estimated as the movement amount Δy of the car 120. In addition, the method for estimating the movement amount Δy based on the y component of the peak coordinate position is not limited to a specific method. For example, it can be estimated based on the peak coordinates of the maximum position, or it can be estimated by using a few points near the maximum position for least squares fitting, etc.

[0064] Next, the movement amount calculation unit 320 calculates the elapsed time k×Δt from image I(ik) to image I(i), and calculates the moving speed V of the car 120 by taking the ratio of the movement amount Δy to the time k×Δt (moving speed V=Δy / (k×Δt)) (step S103).

[0065] In addition, the movement amount calculation unit 320 sequentially accumulates and adds the movement amount Δy of the car 120 to the reference position of the brightness mark 150, thereby calculating the total movement amount of the car 120 starting from the above-mentioned reference position. The reference position of the brightness mark 150 is identified as the reference for movement amount calculation by the brightness mark identification unit 330 in step S105 (step S104).

[0066] On the other hand, in step S105 , the luminance marker recognition unit 330 calculates reference position related information using the luminance marker 150 included in the image I(i) of the i-th frame as a reference for calculating the movement amount.

[0067] More specifically, the brightness mark recognition unit 330 reads the image I(i) of the i-th frame from the storage element, and determines whether the brightness mark 150 is present in the image I(i) by performing image recognition processing on the image I(i). When the brightness mark 150 is present in the image I(i), the brightness mark recognition unit 330 uses the brightness mark 150 as a new reference for the movement amount calculation to recalculate the reference position associated information. Specifically, the brightness mark recognition unit 330 calculates the reference position of the brightness mark 150 newly used as the reference for the movement amount calculation, and the ID ( Figure 8 ID pattern 820) etc. On the other hand, when the brightness mark 150 does not exist in the image I(i), the brightness mark recognition unit 330 does not update the reference for movement amount calculation, and continues to use the reference position association information calculated by the most recent measurement processing.

[0068] By performing the processing of step S105 in this manner, the brightness mark recognition unit 330 can calculate the reference position related information using the latest brightness mark 150 included in the image I(i) that changes according to the movement of the car 120 as a reference for calculating the movement amount. Figure 1 Specifically, for example, when the car 120 (measuring device 110) rises in the y-axis direction, until the car 120 exceeds the brightness mark 150-1 and reaches the brightness mark 150-2, the brightness mark 150-1 becomes the reference for calculating the amount of movement, and the reference position related information based on the brightness mark 150-1 is calculated. In addition, after the car 120 (measuring device 110) reaches the brightness mark 150-2, until it reaches the next brightness mark 150, the brightness mark 150-2 becomes the reference for calculating the amount of movement, and the reference position related information based on the brightness mark 150-2 is calculated.

[0069] When step S104 and step S105 are completed, the control unit 310 (or the communication unit 340) transmits the car movement related information calculated in steps S102 to S104 and the reference position related information calculated in step S105 to the elevator control unit 130 via the communication unit 340 (step S106). Then, the control unit 310 increases the value of the frame number "i" by 1 (step S107).

[0070] Then, the control unit 310 checks whether the measuring device 110 is powered (step S108). As long as the power is supplied in step S108 ("Yes" in step S108), the image processing unit 240 repeats the processing of steps S101 to S107. If the power is cut off ("No" in step S108), the measurement process ends.

[0071] exist Figure 4 In the measurement process shown, as described above, the brightness mark 150 (more strictly speaking, the reference position of the brightness mark 150) identified by the image recognition processing of the brightness mark recognition unit 330 is set as the reference position, and the movement amount of the car 120 starting from the reference position is accumulated to identify the absolute position between the reference positions of the car 120. Therefore, when the car is running, errors may accumulate during the period until the reference position of the next brightness mark 150 is reached. In this case, when the car 120 travels back and forth in a section without a reference position, errors may always continue to accumulate, which is undesirable in terms of the measurement accuracy of the absolute position. In order to eliminate such accumulation of errors, in the present embodiment, at least one brightness mark 150 is set between floors. Specifically, for example, when the interval between floors is 4 meters, the setting interval of the brightness mark 150 is set to less than 4 meters.

[0072] As described above, in the elevator system 10, by performing measurement processing by the image processing unit 240 of the measurement system 100 (measuring device 110), when the elevator car 120 moves, the absolute position of the elevator car 120 can be calculated by accumulating and adding the relative movement amount Δy starting from the reference position of the brightness mark 150 serving as a reference.

[0073] Next, as a supplement to the above measurement process, refer to Figure 5 The calculation image of the movement amount Δy of the car 120 by the movement amount calculation unit 320 will be described. In addition, as a supplementary explanation related to the captured image (image (i)) which is the object of the measurement process, Figure 6 and Figure 7 The following describes the design of the exposure time of the imaging unit 230 for preventing the occurrence of subject shake in the captured image.

[0074] Figure 5 This is a diagram for explaining the changes in the captured image when the car 120 moves. Strictly speaking, as described above, the imaging unit 230 reads the optical signal formed on the imaging surface and converts it into an electrical signal, and the image processing unit 240 (control unit 310) performs image processing on the electrical signal to generate a captured image. However, for the sake of simplicity, in the following description, the electrical signal converted by the imaging of the imaging unit 230 is sometimes replaced by the "captured image" that has been image-processed by the control unit 310 for processing. Figure 5 , an example is shown in which the image of the brightness mark 150 is not included in the captured image, but the captured image may include the image of the brightness mark 150.

[0075] When the guide rail 140 as the object is photographed from the car 120 moving at a moving speed V, as shown in FIG. Figure 5 As shown, at time t and time (t+k×Δt), there is a deviation in the moving direction (y-axis direction) between the two captured images 520-1 and 520-2 of the scattered brightness distribution 510 on the surface of the object (the surface of the guide rail 140). In addition, Δt represents the frame period, k is an integer value, and represents the number of unit frames passing when the specified timing is used as the starting point (k=0). At this time, the displacement amount Δy representing the deviation is equivalent to the movement amount Δy of the car 120. Therefore, as in Figure 4 As described in steps S102 to S104 of the present invention, the movement amount calculation unit 320 can calculate the movement amount of the car 120 by performing comparison processing on captured images between different frames.

[0076] Figure 6 1 is a diagram showing an example of a timing chart of a strobe signal transmitted from the control section 310 to the imaging section 230 .

[0077] like Figure 6 As shown, the control unit 310 of the image processing unit 240 sends a strobe signal 610 ( Figure 6 In response to the pulse of the strobe signal 610 sent from the control unit 310, the shooting unit 230 performs exposure only during the pulse width T (exposure time T), and shoots the light signal imaged on the shooting surface. In addition, in the measuring device 110 of the present embodiment, in parallel with the strobe signal 610 being sent from the control unit 310 to the shooting unit 230, the strobe signal 610 may be sent from the control unit 310 to the light transmitting unit 210, and the light transmitting unit 210 that receives the strobe signal 610 may light up the light source only during the exposure time T. By performing such lighting control, the average output power per unit time of the light transmitting unit 210 can be reduced, thereby achieving the effect of suppressing the power required for driving and heat dissipation.

[0078] Figure 7 is a diagram showing an example of brightness distribution of a captured image during exposure time. In more detail, Figure 7 2 shows an example of brightness distribution of a captured image when scattered light emitted from the brightness mark 150 provided on the guide rail 140 is formed on the imaging unit 230 during one exposure time T. FIG.

[0079] exist Figure 7 In FIG. 7 , since the exposure time is set to T, if the start time in the exposure time is set to t, the end time in the exposure time is represented by t+T. The scattered light brightness distribution 710-1 is the brightness distribution of the scattered light on the imaging surface at the start time t in the exposure time T, and the scattered light brightness distribution 710-2 is the brightness distribution of the scattered light on the imaging surface at the end time t+T in the exposure time T. Figure 7 It can be seen from the scattered light brightness distributions 710-1 and 710-2 that, during the period of the selection signal 610 sent from the control unit 310 to the imaging unit 230, the brightness distribution of the scattered light imaged on the light receiving surface (imaging surface) of the imaging unit 230 moves along the moving direction (y-axis direction) of the car 120. As a result, the subject shakes in the y-axis direction in the captured image 720 during this period (exposure time T).

[0080] The above-mentioned subject shaking is caused by the accumulation of images of the scattered light brightness distribution that continuously changes from the start time t within the exposure time T to the scattered light brightness distribution 710-2 at the end time t+T within the exposure time T, thereby causing "blurring" in the moving direction (y-axis direction) of the exposed captured image 720. That is, in the captured image 720, the amplitude of V×T, which is proportional to the exposure time T in the imaging unit 230, or more strictly speaking, the product of the moving speed V of the car 120 and the exposure time T, is blurred. In addition, the following problem can be conceived: if image processing is performed in a state where the above-mentioned subject shaking (blurring) occurs in the captured image 720, the moving speed or position of the car 120 cannot be accurately calculated.

[0081] Regarding the above problem, in order to suppress the shaking of the subject in the moving direction (y-axis direction) of the car 120, it is necessary to consider the moving speed V of the car 120 and make the exposure time T sufficiently small (short). Therefore, in this embodiment, the spatial resolution δ of the pixels of the imaging unit 230 is set to x The maximum moving speed V of the car 120 max The time shorter (smaller) than the time obtained by the above method is set as the exposure time T of the imaging unit 230. That is, by using the required spatial resolution δ x and the maximum moving speed V of the car 120 max To determine the exposure time T, to satisfy "T < δ x / V max " Specifically, for example, for an elevator car 120 requiring a maximum moving speed of 300 m per minute, when a spatial resolution of 0.5 mm is required, the exposure time may be required to be controlled below 100 μs.

[0082] (1-3) Characteristics of Brightness Mark 150

[0083] The features of the brightness mark 150 that can be used in the measurement system 100 of this embodiment will be described in detail below.

[0084] First, the shape of the brightness mark 150 will be described.

[0085] Figure 8 is a diagram showing a specific example of the brightness mark 150 . Figure 8 As a specific example of brightness marks 150 of different shapes, in Figure 8 (A) shows an example of a brightness mark 151. Figure 8 (B) shows an example of a brightness mark 152. Figure 8 (C) shows an example of a brightness mark 153. The features of each of the brightness marks 151 to 153 will be described later, and first, the common structure of the brightness mark 150 will be described.

[0086] like Figure 8 As shown in the various views in FIG. 1 , the brightness mark 150 includes a reference line 810 as a reference for an absolute position and an ID pattern 820 for distinguishing a reference position by combining the configuration of light and dark brightness. The ID pattern 820 has a different identification signal for each pattern. In addition, a blank space of a predetermined amount or more is set outside the print area of ​​the brightness mark 150. By providing this blank space, even if the car 120 shakes in the vertical direction (x-axis direction) orthogonal to the moving direction (y-axis direction) during travel, the camera unit 230 can recognize the brightness mark 150 without causing the print area to deviate outside the filming area. That is, in order for the camera unit 230 to reliably converge the print area of ​​the brightness mark 150 within the filming area even if the car 120 shakes in the x-axis direction during travel, the length of the side of the brightness mark 150 in the x-axis direction is less than the length obtained by subtracting the displacement of the maximum shaking in the x-axis direction that can occur in the car 120 from the length of the side of the filming area in the x-axis direction. Specifically, for example, when the measuring device 110 having an imaging area of ​​13 mm is used for the car 120 capable of generating a car shake of 5 mm in the x-axis direction, the length of the side of the brightness mark 150 in the x-axis direction is required to be at least 8 mm or less.

[0087] The brightness mark 150 (brightness marks 151 to 153) of this embodiment has a characteristic brightness change at least in the x-axis direction. By utilizing this brightness change, the measuring device 110 can improve the detection accuracy by minimizing the influence of the shaking of the object even when the car 120 moves at high speed in the y-axis direction. Fig. 9 A specific example for illustrating the effect of improving detection accuracy is shown in FIG.

[0088] Fig. 9 1 is a diagram showing an example of brightness distribution of a captured image of a brightness mark 151. Figure 7 Similarly, in Fig. 9 In Figure 8 The brightness mark 151 shown as an example in (A) is an object, and shows an example of the brightness distribution of the captured image during one exposure time T. As described above, Figure 7 When the car 120 moves at high speed, the subject may also shake in the moving direction (y-axis direction) in the captured image. Fig. 9In the exposure time T, the scattered light brightness distribution 910-1 at the start time t within the exposure time T to the scattered light brightness distribution 910-2 at the end time t+T within the exposure time T, the image of the scattered light brightness distribution that changes continuously every moment is accumulated, so that the subject shakes in the moving direction (y-axis direction) of the captured image 920 after exposure. However, the brightness mark 150 (for example, the brightness mark 151) of the present embodiment has a characteristic brightness change in the x-axis direction, so that even if the subject shakes in the moving direction (y-axis direction) of the car 120 on the captured image 920, the pattern of brightness change (brightness and darkness of the edge) in the x-axis direction is not affected (refer to Fig. 9 That is, even if the subject shakes in the y-axis direction in the captured image 920, the measuring device 110 (image processing unit 240) can detect the bright and dark edges set in the x-axis direction where the subject shake does not occur, thereby improving the detection accuracy of the ID pattern 820.

[0089] In the brightness mark 150 (brightness marks 151 to 153) of the present embodiment, the interval of brightness change of the ID pattern 820 is larger than the spatial resolution δx determined by the pixels of the imaging unit 230. This is because, assuming that the interval of brightness change of the ID pattern 820 is larger than the spatial resolution δx determined by the pixels of the imaging unit 230, x When the spatial resolution δ of the imaging unit 230 is smaller (fine), the imaging unit 230 cannot distinguish the brightness change. x When the period of the ID pattern 820 is 0.5 mm, the period of the light and dark brightness change is at least greater than 0.5 mm.

[0090] In addition, the combination of the ID pattern 820 in the brightness mark 150 (brightness mark 151-153) of the present embodiment has a combination number sufficient to distinguish the reference position information in the same shaft. Specifically, for example, when the brightness mark 150 is set every 4m in a shaft with a total height of 100m, at least 25 brightness marks 150 are set, so the ID pattern 820 needs a combination number of at least 25 patterns.

[0091] In addition, in the brightness mark 150 (brightness marks 151 to 153) of the present embodiment, the ID pattern 820 does not have periodicity in the moving direction (y-axis direction). This is because the image processing (movement amount calculation processing) of the movement amount calculation unit 320 described above is performed even for the place where the brightness mark 150 is set. Therefore, assuming that the ID pattern 820 of the brightness mark 150 has periodicity in the moving direction (y-axis direction) of the car 120, the periodicity is reflected in the movement amount calculation processing, so that the calculated movement amount Δy of the car 120 (and the total movement amount) has uncertainty corresponding to the period, and the movement amount may not be uniquely estimated.

[0092] Next, explain Figure 8 (A)~ Figure 8 (C) Characteristics of each of the brightness marks 151 to 153. Each of these brightness marks 151 to 153 has the characteristics of the brightness mark 150 of the present embodiment described above.

[0093] Figure 8 The brightness mark 151 shown in (A) is an example of a brightness mark 150 in which the reference line 810 is separated from the ID pattern 820. The ID pattern 820-1 of the brightness mark 151 is composed of a one-dimensional bar code with different light and dark in the x-axis direction. In the case of the brightness mark 151, by detecting the position of the light and dark edge in the ID pattern 820-1, the information of the ID used to distinguish the reference position can be identified. By detecting the position where the brightness difference is greater than a specified threshold value using the light and dark brightness difference as an indicator, the light and dark edge can be identified. Similarly, by detecting the coordinate (y coordinate) where the brightness changes sharply in the y-axis direction, the position of the reference line 810-1 can also be identified.

[0094] In this embodiment, by using the brightness mark 151 described above, it is possible to have the characteristics of the brightness mark 150 of the present embodiment described above and to realize a brightness mark with a simpler structure.

[0095] Figure 8 The brightness mark 152 shown in (B) is an example of the brightness mark 150 in which the reference line 810 and the ID pattern 820 are integrated. The ID pattern 820-2 of the brightness mark 152 is composed of a two-dimensional light and dark mosaic pattern in the xy axis direction, and the reference line 810-2 is formed as one side of the above light and dark mosaic pattern. Figure 8 (A) shows a one-dimensional barcode ID pattern 820-1 with light and dark. Similarly, a light and dark mosaic pattern like ID pattern 820-2 can detect light and dark by brightness difference detection, and as a result, the pattern combination can be identified. In addition, by detecting the corner position of the rectangle of brightness mark 152, the position of reference line 810-2 can be determined.

[0096] In this embodiment, when the brightness mark 152 is used, the number of pattern combinations can be increased in the y-axis direction compared to the ID pattern 820-1 composed of a one-dimensional barcode in the x-axis direction, thereby increasing the amount of information that can be written (for example, layer height information, etc.). In addition, even for partial pattern defects caused by stains attached to the pattern, partial peeling of the pattern, saturation of pixel values ​​caused by external light, etc., the redundant structure of the pattern can be easily obtained by increasing the number of pattern combinations, thereby realizing a more robust brightness mark.

[0097] Figure 8 The brightness mark 153 shown in (C) is an example of the brightness mark 150 after the baseline 810 and the ID pattern 820 are integrated. The ID pattern 820-3 of the brightness mark 153 is composed of numbers and characters. When using the brightness mark 153, before measuring the position of the car 120, for example, the image processing unit 240 learns each ID pattern 820-3 through processing such as machine learning, assigns position information to the feature points of each ID pattern 820-3 obtained by learning and stores it, so that when measuring the position of the car 120, the image processing unit 240 can read the information (numbers or characters) contained in the ID pattern 820-3 in the captured image. In addition, like the baseline 810-2, the baseline 810-3 is configured as one side of the rectangle of the brightness mark 153, so the position can be determined by detecting the corner position of the rectangle of the brightness mark 153.

[0098] In the present embodiment, when the brightness mark 153 as described above is used, since a person can easily recognize the information included in the ID pattern 820-3 from the image captured by the brightness mark 153 of the imaging unit 230, the brightness mark 153 can be used for purposes other than the object of the reading process of the measuring device 110. For example, the brightness mark 153 can be used to distinguish the number and position of components such as the guide rail 140 when installing, constructing or inspecting the guide rail 140.

[0099] In addition, in the measurement system 100 of the present embodiment, in order to improve the recognition accuracy of the brightness mark 150, in addition to the ID pattern 820 formed by the artificially provided tape or notch, stains or scratches naturally attached to the guide rail 140 can also be used as the ID pattern 820. In this case, the stains and scratches can be stored in the measurement device 110 or the elevator control unit 130 in advance, and can be used by associating the stains and scratches with their position information.

[0100] Next, the size of the brightness mark 150 will be described.

[0101] In this embodiment, the length L of the side of the brightness mark 150 in the y-axis direction is mark The length L of the side in the y-axis direction passing through the imaging region of the imaging unit 230 is obs Subtract the maximum moving speed V of the moving object (car 120) max Multiply by the frame time Δt corresponding to the generation cycle of the strobe signal 610 (refer to Figure 6 ) and the length obtained after the size is less than that obtained. That is, it is composed of "L mark ≤L obs -V max ×Δt” holds true (the equal sign in the above inequality can be excluded). With such a structure, the image processing unit 240 can obtain a complete captured image of the brightness mark 150 in at least one frame between two consecutive frames. Fig.10 This is to illustrate the necessity that the size of the brightness mark 150 satisfies the above relationship.

[0102] Fig.10 1 is a diagram for explaining the size relationship between the brightness mark 150 and the imaging area of ​​the measuring device 110. Fig.10 , an example is shown in which the length L of the side in the y-axis direction of the brightness mark 150 is mark The relationship "L mark ≤L obs -V max ×Δt” structure, a complete captured image of the brightness mark 150 cannot be obtained in at least one frame between two consecutive frames. The image processing unit 240 (control unit 310) sets the frame period of the electrical signal of the captured image obtained from the imaging unit 230 to Δt.

[0103] like Fig.10 As shown in FIG. 1 , when two consecutive frames (the first frame and the second frame) pass, the photographing area 1010 of the measuring device 110 (photographing unit 230) moves along the moving direction of the car 120, that is, the y-axis direction. Specifically, Fig.10 , moves from the photographing area 1010 - 1 at the start time t of the first frame to the photographing area 1010 - 2 at the start time t+Δt of the second frame.

[0104] Here, the maximum moving distance between frames is L max The maximum moving speed V of the car 120 can be used max and the frame period Δt to express (L max =V max ×Δt). In addition, the length of the side of the imaging region 1010 in the moving direction (y-axis direction) is denoted as L obsWhen , the length of the side in the y-axis direction of the region where the photographing regions 1010 in two consecutive frames overlap is given by “L obs -L max ” given.

[0105] exist Fig.10 In the figure, the length of the side in the moving direction (y-axis direction) of the overlapping area is shown as an example. obs -L max " is smaller than the size of the brightness mark 150 (the length of the side in the moving direction) L mark The situation, that is, "L mark >L obs -V max ×Δt” is established, then, if Fig.10 As shown, in either the first frame (time t) or the second frame (time t+Δt), sometimes the brightness mark 150 cannot be completely contained within the shooting area 1010, and only a portion of the brightness mark 150 is captured. As a result, the image processing unit 240 fails to read the brightness mark 150 from the captured image.

[0106] Above, Fig.10 As a counter-example, in this embodiment, in order to completely capture the entire brightness mark 150 in at least one of the captured images of two consecutive frames (time t, time t+Δt), the size L of the brightness mark is required to be mark For "L obs -V max ×Δt” or less. For example, when the frame period (Δt) is 1 mm / s and the length of the side (L) in the moving direction (y-axis direction) of the imaging region 1010 is obs ) is 13 mm to identify the brightness mark 150, for the required maximum moving speed (V max ) is the length (L) of the side in the moving direction (y-axis direction) at the brightness mark 150 of the car 120 at 300 m / min. mark ) is required to be at least 8mm.

[0107] In addition, in this embodiment, for the purpose of redundancy, multiple brightness marks 150 representing the same ID pattern 820 can also be arranged. In this case, the overall size of the multiple brightness marks 150 arranged does not need to meet the above-mentioned requirement "L mark ≤L obs -V max×Δt", but in at least one of the multiple brightness marks 150 representing the same ID pattern 820, the above requirements are required to be met. In addition, considering the ease of setting, for example, when the brightness mark 150 is affixed to the guide rail 140 by a sticker, etc., only the brightness mark 150 printed on the inside of the sticker satisfies the above requirements, and the size of the sticker can be sufficiently larger than that of the brightness mark 150.

[0108] As described above, according to the measurement system 100 of this embodiment, when the moving body (elevator car 120) moves, the measurement device 110 mounted on the moving body measures the reference Figure 8 to Figure 10 The captured image of the characteristic brightness mark 150 is performed Figure 4 The measurement processing shown in the figure can calculate the absolute position information of the moving body on the moving path at high speed and high precision. That is, according to the measurement system 100 of this embodiment, the reference position set in the shaft is highly accurately identified from the moving body moving at high speed, and the absolute position of the moving body in the shaft can be measured at high speed and high precision by sequentially accumulating the moving distance of the moving body from the reference position. Moreover, the specified control unit (elevator control unit 130) can perform operation control of the moving body and control of the safety device based on the absolute position information of the moving body calculated by the measurement device 110.

[0109] (1-4) Return operation control of mobile objects when power is restored

[0110] In addition, by using the measurement system 100 of the present embodiment, the elevator system 10 can implement operation control for moving the moving body to a specified return position when power is restored after a power outage such as a power outage (specifically, return operation control for returning the elevator car 120 that has stopped due to a power outage to the nearest floor).

[0111] Fig.11 1 is a conceptual diagram for explaining the process of the return operation control of the elevator car 120. Fig.11 , describing the process of returning the elevator car 120 that has stopped at the stop position 1111 due to power outage to the nearest floor 1120 when power is restored.

[0112] First, when the elevator system 10 is installed, a floor height table is prepared in advance, which corresponds the reference position 1112 where the brightness mark 150 is set and the floor position 1113 of each floor, for example, the elevator control unit 130 stores the floor height table in advance. The reference position 1112 is the height corresponding to the reference line 810 provided by each brightness mark 150, and the floor position 1113 is the height of the measuring device 110 when the car 120 stops at the corresponding floor (for example, the floor 1120).

[0113] However, in the elevator system 10, when the power is cut off due to a power outage or the like, the movement of the car 120 and the like stops, and at this time, the position information of the car 120 measured by the measuring device 110 before the power is cut off may be lost due to the power cut off. Therefore, when the elevator control unit 130 returns the car 120 to the nearest floor 1120 after the power is restored, if the car 120 is returned to the nearest floor 1120 based on the position information measured before the power is cut off, a large error may occur.

[0114] In order to solve the above problem, in the elevator system 10 of the present embodiment, when recovering from power failure, the elevator control unit 130 first raises or lowers the car 120 from the position when power was restored (the stop position 1111 when power was cut off), and searches for the brightness mark 150 located at the shortest distance. That is, Fig.11 In the process, as shown by arrow 1131, the car 120 is moved from the stop position 1111 to the reference position 1112 where the brightness mark 150 is provided.

[0115] Next, the measuring device 110 reads the ID pattern 820 using a combination of light and dark brightness changes from the captured image of the brightness mark 150 having a reference position 1112, obtains the position information related to the reference position 1112 (in other words, the reference line 810 of the brightness mark 150), and sends it to the elevator control unit 130.

[0116] The elevator control unit 130 calculates the moving distance of the measuring device 110 to the floor position 1113 when the car 120 is moved to the nearest floor 1120 based on the position information of the reference position 1112 acquired by the measuring device 110 and the pre-stored floor height table. Therefore, the elevator control unit 130 moves the car 120 by the calculated moving distance, such as Fig.11 As shown by the arrow 1132 in FIG. 1 , the car 120 can accurately return to the nearest floor 1120 .

[0117] (2) Implementation Method 2

[0118] Fig.12 The diagram shows a measuring device 1200 according to Embodiment 2 of the present invention, focusing on an example of the internal structure of an imaging unit 1220. The measuring device 1200 according to Embodiment 2 is characterized in that it has a measuring device capable of measuring the z-axis direction (see FIG. Figure 1 ) is shaken while keeping the imaging magnification in the shooting unit 230 unchanged, but the other structures are the same as the measuring device 110 of embodiment 1, so the detailed description is omitted.

[0119] exist Fig.12 In FIG. 1 , scattered light from the guide rail 140 and the brightness mark 150 is shown by dashed lines with arrows (eg, scattered light 1211 to 1213). Fig.12 As shown, the imaging unit 1220 images the scattered light from the guide rail 140 and the brightness mark 150 onto the shooting unit 230. Specifically, the imaging unit 1220 is configured to include an objective lens 1221 (first lens), an aperture 1222, and a focusing lens 1223 (second lens). The objective lens 1221 is arranged opposite to the guide rail 140, and focuses the scattered light scattered by the guide rail 140. The aperture 1222 limits the amount of scattered light (scattered light 1211 to 1213) focused by the objective lens 1221. The focusing lens 1223 is arranged between the aperture 1222 and the shooting unit 230, focuses the scattered light whose amount is limited by the aperture 1222, and sends the focused scattered light to the shooting surface of the shooting unit 230.

[0120] In the imaging unit 1220 of the present embodiment, in order to eliminate the influence of the change in magnification when the guide rail 140 as the photographed object (detection object) shakes relative to the car 120 in the z-axis direction, at least the object side (the guide rail 140 side) is telecentrically configured, and in order to suppress the geometric aberration generated in the imaging unit 230, an image is formed on the imaging unit 230 through two or more lenses. In addition, the imaging unit 1220 may also have a telecentric optical configuration on the image side (the imaging unit 230 side), and in this case, the imaging unit 1220 plays a role in expanding the dimensional tolerance in the z-axis direction (the installation tolerance in the z-axis direction) when the imaging unit 230 is installed.

[0121] That is, in the measuring device 1200 of the present embodiment, the center of the imaging surface of the imaging unit 230, the optical axis of the condensing lens 1223, the center of the aperture 1222, and the optical axis of the objective lens 1221 are arranged to be located on the same straight line, and the aperture 1222 is arranged at the focal position of the objective lens 1221 on the imaging unit 230 side, and is arranged at the focal position of the condensing lens 1223 on the objective lens 1221 side.

[0122] In addition, if Fig.12 As shown, in this embodiment, after the scattered light from the guide rail 140 passes through the objective lens 1221, it is imaged on the imaging surface of the imaging unit 230 via the condenser lens 1223, and the scattered light rays 1211 to 1213 in the above-mentioned scattered light are the principal rays of this imaging optical system. That is, the objective lens 1221, the aperture 1222 and the condenser lens 1223 are arranged so that the scattered light rays 1211 to 1213 pass through the center of the aperture 1222, so that the scattered light rays 1211 to 1213 are always emitted from the scattering surface of the guide rail 140 in parallel with the optical axis of the objective lens 1221, and are always incident on the imaging unit 230 in parallel with the optical axis of the condenser lens 1223.

[0123] As described above, according to the measuring device 1200 of the present embodiment, even if the image of the guide rail 140 shakes in the optical axis direction (z-axis direction), the magnification of the image formed on the imaging surface of the imaging unit 230 can be kept constant, and even if the mounting position of the imaging unit 230 in the z-axis direction is offset, the magnification of the image formed on the imaging surface of the imaging unit 230 can be kept constant. As a result, the dimensional tolerance when the imaging unit 2220 and the imaging unit 230 are mounted can be made larger, and a more robust optical system can be constructed. In addition, by using two lenses including the objective lens 2221 and the condenser lens 2223 for the imaging unit 2220, it is also expected that the influence of the geometric aberration of the imaging unit 2220 generated in the imaging unit 230 can be reduced.

[0124] In addition, in the present embodiment, in the imaging unit 220, both sides of the objective lens 2221 can be spherical, or one side of the objective lens 2221 can be spherical and the other side can be flat, and can also be configured as a glass lens. In addition, the shape of the surface through which the light of the condenser lens 2223 passes can be configured to have both sides spherical, or one side can be spherical and the other side can be flat, and can be configured as a glass lens. With such a configuration, in the measuring device 1200 of the present embodiment, a more inexpensive and more durable imaging unit 2220 can be configured.

[0125] (3) Implementation Method 3

[0126] Fig.13 This figure shows a measuring device 1300 according to Embodiment 3 of the present invention, focusing on an example of the internal structure of an imaging unit 1320. The measuring device 1300 according to Embodiment 3 has the same structure as the measuring device 1200 according to Embodiment 2, except that a part of the internal structure of the imaging unit 1320 is different, and detailed description of the points common to Embodiment 2 is omitted.

[0127] exist Fig.13 In FIG. 1 , scattered light from the guide rail 140 and the brightness mark 150 is shown by dashed lines with arrows (eg, scattered light 1311 to 1313). Fig.13 As shown, the imaging unit 1320 images the scattered light from the guide rail 140 and the brightness mark 150 to the shooting unit 230. Fig.12 Similar to the imaging unit 1220 of the embodiment 2 shown, the imaging unit 1320 is configured to include an objective lens 1321 (first lens), an aperture 1322 and a focusing lens 1323 (second lens), and as a structure unique to this embodiment, the imaging unit 1320 includes a mirror 1324.

[0128] Here, the structures and functions of the objective lens 1321, the aperture 1322 and the focusing lens 1323 are respectively Fig.12The objective lens 1221, aperture 1222 and condenser lens 1223 shown in the figure have the same structure and function, and are optically arranged telecentrically on the object side (guide rail 140 side), and are optically arranged telecentrically on the image side (photographing unit 230 side). In addition, the mirror 1324 is arranged to face the guide rail 140, and the scattered light scattered by the guide rail 140 is reflected toward the objective lens 1321.

[0129] The measuring device 1300 of this embodiment has the above-mentioned structure, and thus can obtain the same effect as the measuring device 1200 of the second embodiment. In addition, the measuring device 1300 of this embodiment can realize a more compact structure by using the mirror 1324. Fig.13 and Fig.12 By comparison, in the measuring device 1300, the imaging unit 1320, the shooting unit 230 and the image processing unit 240 (not shown) can be arranged close to the top of the car 120, so that the measuring device 1300 can be placed on the top of the car 120 without using a special clamp.

[0130] (4) Implementation Method 4

[0131] Fig.14 This figure shows a measuring device 1400 according to a fourth embodiment of the present invention, focusing on an example of the internal structure of an imaging unit 1420. The measuring device 1400 according to the fourth embodiment differs from the measuring device 1200 according to the second embodiment in which the imaging unit 1220 is configured in a dark-field optical configuration in that the imaging unit 1420 is configured in a bright-field optical configuration. However, the measuring device 1400 according to the fourth embodiment has a substantially similar structure to that of the second embodiment, and detailed description of the common points with the second embodiment is omitted.

[0132] exist Fig.14 In FIG. 1 , scattered light from the guide rail 140 and the brightness mark 150 is shown by dashed lines with arrows (eg, scattered light 1411 to 1413). Fig.14 As shown, the imaging unit 1420 is configured in a bright field optical configuration to image the scattered light of the illumination light from the light transmitting unit 210 to the shooting unit 230. Specifically, the imaging unit 1420 is configured to include an objective lens 1421 (first lens), an aperture 1422, and a focusing lens 1423 (second lens). The objective lens 1421 is configured on the guide rail 140 in a direction to perform regular reflection on the emitted light from the light transmitting unit 210 of the shooting unit 230, and focuses the scattered light in the guide rail 140. In addition, the structures and functions of the objective lens 1421, the aperture 1422, and the focusing lens 1423 are respectively similar to those of FIG. Fig.12The objective lens 1221, aperture 1222 and condenser lens 1223 shown have the same structure and function, and are optically arranged telecentrically on the object side (guide rail 140 side) and also on the image side (imaging unit 230 side).

[0133] The measuring device 1400 of the present embodiment has the above-described structure, and thus can obtain the same effects as the measuring device 1200 of Embodiment 2. Furthermore, in the measuring device 1400 of the present embodiment, by configuring the imaging unit 1420 in a bright field optical configuration, the amount of scattered light incident on the imaging unit 230 can be increased, and thus the effect of improving the processing accuracy of the movement amount calculation processing and the brightness mark recognition processing performed by the image processing unit 240 can be obtained.

[0134] (5) Implementation Method 5

[0135] In this embodiment, a measurement system 1500 is described in which the internal structure (light transmission unit 210, imaging unit 220, imaging unit 230, image processing unit 240) of the measurement device 110 and the brightness mark 150 in the measurement system 100 of Embodiment 1 are made redundant.

[0136] Fig.15 1 is a diagram showing a configuration example of a measurement system 1500 according to Embodiment 5 of the present invention. Fig.15 As shown, the measuring system 1500 is composed of: a measuring device 1510 having two or more measuring units 1511 (respectively measuring units 1511-A and 1511-B); a determining unit 1520 disposed between the measuring device 1510 and the elevator control unit 130; and two or more brightness marks 150 (respectively brightness marks 150-A and 150-B) attached to at least two or more positions of the guide rail 140. In addition, although Fig.15 The measurement system 1500 shown has a duplex structure and a redundant structure. However, in the present embodiment, the redundant structure of the measurement system 1500 is not limited to the duplex structure, and may be a triple or higher redundant structure.

[0137] In the measuring device 1510, the measuring parts 1511-A and 1511-B respectively have the same internal structure as the measuring device 110. Specifically, the measuring part 1511-A includes a light transmitting part 210-A, an imaging part 220-A, a shooting part 230-A, and an image processing part 240-A, and the measuring part 1511-B includes a light transmitting part 210-B, an imaging part 220-B, a shooting part 230-B, and an image processing part 240-B.

[0138] In the measuring device 1510 constructed as described above, the measuring units 1511-A and 1511-B independently perform the same measurement processing as the measuring device 110 on the brightness marks 150 (brightness mark 150-A in the case of the measuring unit 1511-A and brightness mark 150-B in the case of the measuring unit 1511-B) which are the shooting objects of each measuring unit 1511 among two or more brightness marks 150 affixed to at least two or more positions of the guide rail 140. That is, the light transmitting unit 210 irradiates the brightness mark 150 as the imaging object with emitted light, the imaging unit 220 images the scattered light of the brightness mark 150 on the imaging surface of the imaging unit 230, the imaging unit 230 converts the optical signal coupled to the imaging surface into an electrical signal corresponding to the brightness of the pixel, and the image processing unit 240 calculates information related to the movement of the car 120 (car movement related information) and information related to the reference position of the brightness mark 150 as the imaging object (reference position related information) based on the captured image generated by performing image processing on the electrical signal. However, as a point different from the measuring device 110, each measuring unit 1511-A, 1511-B sends the calculation results of each image processing unit 240 to the determination unit 1520 instead of the elevator control unit 130.

[0139] Then, the determination unit 1520 performs the comparison processing described in the next paragraph on the signal information (car movement related information and reference position related information) sent respectively from the multiple measuring units 1511 of the measuring device 1510 (in detail, the image processing unit 240), thereby determining the abnormality related to the multiple measuring units 1511 and the brightness mark 150.

[0140] As the comparison process, the determination unit 1520 determines whether at least two pieces of signal information received from the measuring device 1510 are identical. When the determination results in that the two pieces of signal information are identical, the determination unit 1520 can determine that the measuring device 1510 and the brightness marker 150 are operating normally. On the other hand, when the determination results in that any piece of signal information is different from the other pieces of signal information, the determination unit 1520 can determine that at least one of the measuring device 1510 and the brightness marker 150 is abnormal.

[0141] In addition, in the present embodiment, "the signal information is the same" may mean that the content of the signal information as the comparison object is completely consistent, but it may also mean that the content of the signal information as the comparison object is almost consistent (approximately consistent). As a case of complete consistency, for example, the position of the car 120-A sent from the image processing unit 240-A and the position of the car 120-B sent from the image processing unit 240-B have the same value. In addition, as a case of approximate consistency, for example, the difference between the position of the car 120-A sent from the image processing unit 240-A and the position of the car 120-B sent from the image processing unit 240-B is within a predetermined range (for example, the range of allowable error).

[0142] In addition, when the measuring device 1510 has more than three measuring units 1511, in the comparison processing of the determination unit 1520, for example, it is determined whether all pairs of signal information are the same. When it is determined that all pairs of signal information are the same, it is determined that the operation is normal. When it is determined that more than one pair of signal information is different, it is determined that at least one of the measuring device 1510 or the brightness mark 150 has an abnormality.

[0143] As a result of the comparison processing as described above, when it is determined that the measuring device 1510 and the brightness mark 150 are operating normally, the determination unit 1520 sends the signal information received from the measuring unit 1511 (which may be one of the same signal information) and the signal information indicating the determination result that the measuring unit 1511 is operating normally (information indicating normal determination) to the elevator control unit 130.

[0144] On the other hand, when the result of the comparison process is that at least one of the measuring device 1510 or the brightness mark 150 is abnormal, the determination unit 1520 sends signal information indicating the determination result of the abnormal operation of the measuring unit 1511 (information indicating abnormal determination) to the elevator control unit 130. In addition, in addition to the above-mentioned determination of the presence or absence of abnormality, the determination unit 1520 can also identify the type of abnormality by analyzing information related to the captured images obtained by each measuring unit 1511, information related to the movement of the car 120 (car movement related information), information related to the reference position of the brightness mark 150 (reference position related information), etc. In the analysis method, since a known analysis method can be appropriately used, detailed description is omitted, but by identifying the type of abnormality, for example, damage to the components of the measuring device 1510, abnormal vibration caused by looseness or damage of the mounting fixture, deviation of the mounting position, tilt, corrosion, contamination, adhesion of foreign matter, and defect of the brightness mark 150 can be detected.

[0145] As described above, according to the measurement system 1500 of the present embodiment, by adopting a redundant structure, even when an abnormality such as a failure, dirt, or defect occurs in the measurement device 1510 (measurement unit 1511) or the brightness mark 150, the occurrence of the abnormality can be safely detected without causing an obstruction to the operation of the elevator car 120. In addition, when the occurrence of an abnormality is detected, the type of the abnormality can be identified by analyzing the information obtained from the measurement device 1510, so that appropriate recovery work can be quickly performed.

[0146] (6) Other Implementation Methods

[0147] In each of the above-mentioned Embodiments 1 to 5, the case where the present invention is applied to the measuring device of the elevator car 120 in the elevator system is described, but the present invention is not limited thereto and can be widely applied to various other systems, devices, methods and programs.

[0148] For example, the measuring device 110 of Embodiment 1 (or the measuring device of other embodiments) can be applied not only to the operation of elevators, but also to the purpose of detecting the position or speed with high accuracy in vehicles traveling at high speeds such as cars or trains. For example, in an autonomous driving vehicle, the measuring device 110 can be applied to the purpose of position monitoring / speed monitoring on highways, or to the purpose of high-accuracy positioning in parking lots, gas stations, or charging stations.

[0149] Fig.16 1 is a diagram showing a configuration example of a vehicle positioning system 1600 in which the measurement device 110 is applied to a vehicle. Fig.16 (A) shows an example in which the brightness mark 150 is pasted on the road surface 1620. Fig.16 (B) shows an example in which the brightness mark 150 is attached to a wall surface 1630 of a highway.

[0150] like Fig.16 As shown, in the vehicle positioning system 1600, the measuring device 110 is arranged on the side or upper part of a vehicle 1610 (for example, a car or a train), and the vehicle 1610 travels on a road surface 1620. The measuring device 110 outputs signal information useful for controlling the operation of the vehicle 1610 to a vehicle control unit (not shown). The vehicle control unit is provided to, for example, enable the vehicle 1610 that performs automatic driving to move / stop safely.

[0151] In addition, a brightness mark 150 indicating a reference position in the road is attached to a predetermined stationary structure ( Fig.16 (A) The road surface 1620 and Fig.16 (B) on the wall 1630). Fig.16, but in fact, a plurality of brightness marks 150 may be arranged on a stationary structure along the moving direction of the moving body, and each brightness mark 150 includes a corresponding reference line 810 and an ID pattern 820. Specifically, for example, the brightness mark 150 is attached to a wall surface 1630 in front of a traffic light where the vehicle 1610 needs to be stopped safely, or to a road surface 1620 where the vehicle 1610 needs to be positioned and stopped with high precision, such as in a parking lot or a gas station. For example, when the application object of the measuring device 110 is a train, the brightness mark 150 may be arranged along the track on which the train travels.

[0152] By applying the measuring device 110 to the autonomous driving vehicle (vehicle 1610) as described above, Fig.16 The vehicle positioning system 1600 of (A) can use the brightness mark 150 arranged on the road surface 1620 to measure the position of the vehicle 1610 with high accuracy, thereby helping to control the vehicle 1610 to stop at a specified destination (parking lot, gas station, charging station, etc.) with high accuracy. Fig.16 The vehicle positioning system 1600 of (B) can measure the position of the vehicle 1610 with high accuracy using the brightness mark 150 arranged on the wall surface 1630, and can therefore contribute to control to stop the vehicle 1610 safely at a predetermined location (in front of a traffic light, etc.).

[0153] For example, the measuring device 110 of the first embodiment (which may be a measuring device of another embodiment) can also be applied to the operation control of a crane.

[0154] Fig.17 FIG. 1 is a diagram showing a configuration example of a crane positioning system 1700 in which the measuring device 110 is applied to a crane. Fig.17 In the crane positioning system 1700 shown, the measuring device 110 is arranged on the side or the top of a crane 1710 that moves in a single axis direction along a track 1720. Fig.17 In the figure, the track 1720 is equivalent to a stationary structure on which the brightness mark 150 is configured, and the brightness mark 150 is configured along the moving direction of the crane 1710.

[0155] In the crane positioning system 1700, the measuring device 110 captures the wall surface of the rail 1720, measures the movement amount and speed of the crane 1710 (information related to the movement of the crane 1710), and acquires information related to the reference position of the brightness mark 150 by reading the brightness mark 150 attached to the rail 1720. The crane control unit (not shown) of the crane 1710 monitors the operation of the crane 1710 based on the above information useful for controlling the operation of the crane 1710 (i.e., information related to the movement of the crane 1710 and information related to the reference position of the brightness mark 150), and detects position abnormality and speed abnormality.

[0156] As described above, by applying the measuring device 110 to the crane 1710 , the crane positioning system 1700 can improve the safety of the operation control of the crane 1710 during the operation control of the crane 1710 .

[0157] In addition, the above-mentioned embodiments are intended to explain the present invention in an easy-to-understand manner and do not limit the scope of the present invention. In addition, with respect to a part of the structure of each embodiment, other structures may also be added, deleted, replaced, etc. In addition, the above-mentioned structures, functions, processing units, processing units, etc. may also be partially or entirely implemented using hardware obtained, for example, by integrated circuit design. In addition, the above-mentioned structures, functions, etc. may also be interpreted as programs that implement each function respectively by a processor, and are implemented in the form of software by executing the program. Information such as programs, tables, files, etc. that implement each function can be placed in a recording device such as a memory, a hard disk, an SSD (Solid State Drive), or a recording medium such as an IC card, an SD card, or a DVD.

[0158] In addition, the control lines and information lines necessary for explanation are shown in the figure, but not all the control lines and information lines necessary for the product are shown. In fact, it can be considered that almost all the structures are connected to each other.

[0159] Description of symbols

[0160] 10 Elevator System

[0161] 100 Measurement Systems

[0162] 110 Measuring device

[0163] 120 Elevator car (car)

[0164] 130 Elevator Control Unit

[0165] 140 Guide Rail

[0166] 150(151~153) Brightness mark

[0167] 210 Optical transmission unit

[0168] 220 Imaging Department

[0169] 230 Photography Department

[0170] 240 Image Processing Department

[0171] 310 Control Department

[0172] 320 Movement amount calculation unit

[0173] 330 Brightness mark recognition unit

[0174] 340 Ministry of Communications

[0175] 510 Scattered brightness distribution

[0176] 520 captured images

[0177] 610 Strobe signal

[0178] 710, 910 Scattered light brightness distribution

[0179] 720, 920 capture images

[0180] 810 Baseline

[0181] 820 ID pattern

[0182] 1010 Shooting Area

[0183] 1111 Stop position

[0184] 1112 Reference position

[0185] 1113 Floor Location

[0186] 1120 Nearest floor

[0187] 1200, 1300, 1400 measuring devices

[0188] 1211~1213、1311~1313、1411~1413 Scattered light

[0189] 1220, 1320, 1420 Imaging Department

[0190] 1221, 1321, 1421 objective lens

[0191] 1222, 1322, 1422 aperture

[0192] 1223, 1323, 1423 Condenser lens

[0193] 1324 Mirror

[0194] 1500 Measurement System

[0195] 1510 Measuring device

[0196] 1511 Measurement Department

[0197] 1520 Judgment Department

[0198] 1600 Vehicle Positioning System

[0199] 1610 Vehicles

[0200] 1620 Road surface

[0201] 1630 wall

[0202] 1700 Crane Positioning System

[0203] 1710 Crane

[0204] 1720 Guide Rails.

Claims

1. A measuring device, which is arranged on a moving body moving on a moving path and measures the position of the moving body, characterized in that: include: a light transmitting unit that transmits light for irradiating a stationary structure disposed on the moving path in a first direction parallel to the moving direction of the moving body in response to a strobe signal generated at a predetermined period; an imaging unit that images the scattered light from the stationary structure generated by the light on a shooting surface; a photographing unit that acquires a light signal of the scattered light imaged on the photographing surface within an exposure time specified by the strobe signal and converts the light signal into an electrical signal; as well as an image processing unit that generates the strobe signal at the predetermined period, performs image processing on the electrical signal converted by the imaging unit to generate an image, and calculates information related to the absolute position of the moving body based on the image. The image processing unit comprises: a marker recognition process, in which, when the captured image includes an image of a marker disposed on the stationary structure, a reference line representing a reference of an absolute position of the marker is determined using a change in brightness in a second direction perpendicular to the first direction in the captured image; as well as A movement amount calculation process is performed to calculate the movement amount of the moving body from the reference line determined by the marker recognition process.

2. The measuring device according to claim 1, characterized in that The exposure time is set to a value smaller than a time calculated from a ratio between a spatial resolution of an image formed on the imaging plane and a maximum moving speed of the moving object.

3. The measuring device according to claim 1, characterized in that In the movement amount calculation process, the image processing unit generates the captured image of each frame from the electrical signal converted by the imaging unit at a frame period equivalent to the generation period of the strobe signal. In the generated captured images of the plurality of frames, a deviation in an image between a first measurement object image included in a captured image of a previous first frame and a second measurement object image included in a captured image of a second frame subsequent to the first frame is calculated, thereby calculating a moving distance of the moving object from the first frame to the second frame. The moving speed of the moving object is calculated based on the ratio of the calculated moving distance to the time difference between the first frame and the second frame.

4. The measuring device according to claim 1, characterized in that The imaging unit includes a first lens, which focuses scattered light from the stationary structure; an aperture, the aperture limiting the amount of the scattered light obtained after focusing by the first lens; as well as a second lens disposed between the aperture and the imaging surface and configured to focus the scattered light whose light quantity is limited by the aperture, At least the first lens disposed on the stationary structure side is optically arranged in a telecentric manner.

5. A measuring system for measuring the position of a moving object moving on a moving path, characterized in that: include: a measuring device, the measuring device being arranged on the moving body; as well as a marker, wherein the marker is disposed on a stationary structure arranged along a first direction parallel to the moving direction of the moving body on the moving path, and at least one marker is disposed at predetermined intervals along the first direction, The measuring device comprises: a light transmitting unit that transmits light for irradiating a stationary structure arranged on the moving path in a first direction parallel to the moving direction of the moving body in response to a strobe signal generated at a predetermined period; an imaging unit that images the scattered light from the stationary structure generated by the light on a shooting surface; an imaging unit that acquires a light signal of the scattered light imaged on the imaging surface within an exposure time specified by the strobe signal and converts the light signal into an electrical signal; and an image processing unit that generates the strobe signal at the predetermined period, performs image processing on the electrical signal converted by the imaging unit to generate an image, and calculates information related to the absolute position of the moving object based on the image. The image processing unit comprises: Marker recognition processing, in which, when the captured image contains an image of any of the marks, a reference line representing a reference of the absolute position of the mark is determined by using changes in brightness in a second direction perpendicular to the first direction in the captured image; and A movement amount calculation process is performed to calculate the movement amount of the moving body from the reference line determined by the marker recognition process.

6. The measuring system according to claim 5, characterized in that The moving body is an elevator car moving in a hoistway in an elevator system. At least one of the markings is provided on the stationary structure disposed in the hoistway between each floor along the first direction.

7. The measuring system according to claim 5, characterized in that The length of the side of the mark in the first direction is less than the length obtained by subtracting the value obtained by multiplying the maximum moving speed of the moving body by the frame time corresponding to the generation period of the selection signal from the length of the side of the imaging area of ​​the imaging unit in the first direction.

8. The measuring system according to claim 5, characterized in that The length of the side of the mark in the first direction is 8 mm or less.

9. The measuring system according to claim 5, characterized in that The length of the side of the mark in a second direction perpendicular to the first direction is set to be less than the length obtained by subtracting the maximum shaking displacement that can be generated on the moving body in the second direction from the length of the side of the imaging area of ​​the imaging unit in the second direction.

10. The measuring system according to claim 5, characterized in that The marks arranged at different positions on the moving path in the first direction respectively have: said reference line as a reference for the absolute position of the mark; as well as The ID pattern is a pattern that uses a combination of light and dark brightness changes that are different for each of the marks to represent the absolute position information of the reference line. In the mark recognition process, the image processing unit recognizes the ID pattern assigned to the mark relative to the image of the mark contained in the captured image, and performs a decoding process, wherein the decoding process obtains the absolute position information represented by the ID pattern from the recognized ID pattern.

11. The measuring system according to claim 10, characterized in that In the mark, the minimum period of light and dark brightness changes in the ID pattern is greater than the spatial resolution of the image imaged on the shooting surface, and the number of combinations of light and dark brightness changes in the ID pattern is greater than the total number of the marks set at different positions in the first direction on the moving path.

12. The measuring system according to claim 10, characterized in that The ID pattern given to the mark is composed of a combination of light and dark brightness changes arranged in a one-dimensional arrangement in the first direction, In the mark recognition process, the image processing unit performs a decoding process of the ID pattern using the light-dark brightness change in the mark in the first direction as an index.

13. The measuring system according to claim 10, characterized in that The ID pattern given to the mark is composed of a combination of light and dark brightness changes arranged in a two-dimensional arrangement in the first direction and in a second direction perpendicular to the first direction, In the mark recognition process, the image processing unit performs a decoding process of the ID pattern using the light and dark brightness changes in the mark in the first direction and the second direction as an index.

14. The measuring system according to claim 10, characterized in that The image processing unit learns the ID pattern assigned to the marker before performing the decoding process, assigns the corresponding absolute position information of the marker to the feature point of each ID pattern obtained by learning and stores the absolute position information, In the marker recognition process, the feature point recognition process is performed on the captured image, and the ID pattern decoding process is performed using the feature point recognized in the recognition process as an index.

Images