A multi-light circuit combined light curtain based on time-of-flight measurement of the object being measured

Abstract

The present invention provides a multi-optical circuit combined light curtain for measuring an object to be measured based on time of flight, comprising: at least one light curtain, each of the light curtains comprising a plurality of pairs of laser transceiver units and a calculation unit, each of the laser transceiver units comprising a pair of corresponding laser emitting units and laser receiving units, the laser transceiver units being in a pairing channel mode, a mirror channel mode or a TOF channel mode; at certain moments, the emitted laser is emitted by the laser emitting unit, if the emitted laser contacts the surface of the object to be measured, the surface of the object to be measured reflects the emitted laser to form a return laser, and the laser receiving unit receives the return laser; the calculation unit calculates the target value according to the emitted laser, the return laser, the emitted laser parameters, and the return laser parameters. The multi-optical circuit combined light curtain for measuring an object to be measured based on time of flight provided by the present invention can simply, quickly and accurately calculate a variety of parameters of the object to be measured.

Description

Technical Field

[0001] The invention belongs to the field of optical measurement, and in particular relates to a multi-light circuit combined light curtain for measuring a measured object based on time of flight. Background Art

[0002] The measuring light curtain is a high-precision, non-contact measuring tool that is widely used in industrial automation, robot navigation, traffic monitoring, medical and other fields. It is based on optical principles and measures the position, shape, size and other information of the target object through the changes in the light beam transmission between the transmitter and the receiver; the light beam emitted by the transmitter in the light curtain forms a light curtain on the object to be measured, and the object will block or change the light beam when passing through. The receiver detects these changes and analyzes and processes them through the signal processing device to finally obtain the measurement results. This light curtain can be a light array of a single set or multiple sets of sensors, forming a light curtain, which works in a counter-scanning manner, and cooperates with the controller and its software to achieve the measurement of the object's external dimensions. However, in the prior art, a parameter of the object to be measured is usually measured by a light curtain, such as distance or side length, and multiple parameters of the object to be measured are not measured simultaneously by a measuring light curtain; in a multi-light curtain combination product, there is a synchronization error in the measurement between each light curtain, resulting in inaccurate measurement results of the object to be measured.

[0003] Based on the above, this application provides a technical solution to solve the above technical problems. Summary of the invention

[0004] In view of the defects of the measuring light curtain in the prior art, the present invention provides a multi-light circuit combined light curtain for measuring the measured object based on the time of flight, comprising:

[0005] At least one light curtain, each of which includes a plurality of pairs of laser transceiver units and a computing unit, each of which includes a pair of corresponding laser emitting units and laser receiving units, the laser emitting units are arranged opposite to the laser receiving units, and the laser transceiver units are in a pairing channel mode, a mirror channel mode or a TOF channel mode;

[0006] At certain moments, the emitted laser is emitted from the laser emitting unit. If the emitted laser contacts the surface of the object to be measured, the surface of the object to be measured reflects the emitted laser to form a return laser, and the laser receiving unit receives the return laser.

[0007] The calculation unit calculates one or more target values ​​simultaneously according to the emitted laser, the returned laser, the emitted laser parameters, and the returned laser parameters.

[0008] In a specific embodiment of the present invention, the object to be measured and the multi-optical circuit combination light curtain are relatively stationary, and the target value is the distance between the light curtain and the object to be measured, the emitting laser parameter is the moment t1 when the emitting laser is emitted, and the returning laser parameter is the moment t2 when the returning laser returns to the light curtain, and the distance of the object to be measured s=0.5*(t2-t1)*c, where c is the speed of light.

[0009] In a specific embodiment of the present invention, the multi-optical circuit combined light curtain includes a light curtain, the laser transceiver unit of the light curtain used to measure the distance of the object to be measured is set to TOF channel mode, and the laser transceiver units of the remaining parts are in opposite channel mode.

[0010] In a specific embodiment of the present invention, the multi-optical circuit combined light curtain also includes a mirror, which is arranged parallel to the light curtain and is used to reflect the emission laser emitted by the laser emitting unit. The laser transceiver unit is a mirror reflection unit.

[0011] In a specific embodiment of the present invention, the multi-optical circuit combined light curtain includes a main light curtain and a slave light curtain parallel to each other, the target value includes one or more of the distance d1 between the main light curtain and the object to be measured, the distance d2 between the slave light curtain and the object to be measured, the width D1 of the object to be measured, and the shape of the object to be measured, and the measurement of each target value is carried out simultaneously, and the main light curtain and the slave light curtain work independently of each other.

[0012] In a specific embodiment of the present invention, a synchronization module is further included, and the synchronization module controls the main light curtain and the slave light curtain to perform a double synchronization test before the measurement starts. The double synchronization test includes an optical synchronization test and a bus synchronization test. The optical synchronization test includes sequentially lighting up the laser emitting units in the main light curtain and the slave light curtain, and then sequentially turning on the laser receiving units of the main light curtain and the slave light curtain to receive the laser emitted by the laser emitting units.

[0013] In a specific embodiment of the present invention, the width D1 of the object to be measured is L-d1-d2, L is the distance between the main light curtain and the slave light curtain; when the target value includes the shape of the object to be measured, the light curtain is scanned and calculated based on the time-of-flight TOF method, and the shape of the object to be measured is obtained based on the data modeling of each edge of the object to be measured, and the object to be measured can be in any shape.

[0014] In a specific embodiment of the present invention, the relative motion between the object under test and the multi-light circuit combined light curtain includes uniform motion, non-uniform motion, linear motion, and curved motion, and the target value is the motion displacement and average motion speed of the object under test.

[0015] In a specific embodiment of the present invention, the multi-optical circuit combined light curtain includes a main light curtain and a slave light curtain parallel to each other. When the target value includes the motion trajectory of the object to be measured, the distance d1 between the main light curtain and the object to be measured and the distance d2 between the slave light curtain and the object to be measured are continuously measured at each moment, and the motion trajectory of the object to be measured is restored based on the values ​​of d1 and d2 at each moment.

[0016] In a specific embodiment of the present invention, when the target value includes the motion displacement and / or average motion speed of the object to be measured, the position A of the preset point in the object to be measured at the measurement start time T1 and the position B of the preset point in the object to be measured at the measurement end time T2, as well as the measurement duration T are obtained based on the time-of-flight TOF method light curtain, T=T2-T1, the displacement S=BA of the object to be measured, and the average motion speed V=S / T of the object to be measured.

[0017] The present invention can bring at least one of the following beneficial effects: The present invention provides a multi-optical circuit combined light curtain for measuring an object to be measured based on time of flight, comprising: a plurality of light curtains comprising a computing unit and a plurality of pairs of laser emitting units and a laser receiving unit; at a certain moment, an emitted laser is emitted by the laser emitting unit; if the emitted laser contacts the surface of the object to be measured, the surface of the object to be measured reflects the emitted laser to form a returned laser, the laser receiving unit receives the returned laser, and the computing unit calculates a target value according to the emitted laser parameters and the returned laser parameters; the multi-optical circuit combined light curtain proposed in the present invention has a simple structure and is simple to implement, and can directly and quickly calculate multiple target values ​​of the object to be measured at the same time through the light curtain, including one or more of the distance between the light curtain and the object to be measured, the width of the object to be measured, the shape of the object to be measured, the motion state, displacement, and speed of the object to be measured, and can quickly reconstruct and model the object to be measured according to the target value. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The preferred implementation scheme will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and their implementation methods.

[0019] Figure 1 Schematic diagram of the structure of a multi-light circuit combined light curtain in an embodiment of the present invention;

[0020] Figure 2 It is a schematic structural diagram of a preferred embodiment of the present invention;

[0021] Figure 3 It is a schematic structural diagram of a preferred embodiment of the present invention;

[0022] Figure 4 It is a schematic structural diagram of a preferred embodiment of the present invention;

[0023] FIG5(A) is a schematic diagram of a light synchronization test between a master light curtain and a slave light curtain in a preferred embodiment of the present invention;

[0024] FIG. 5(B) is a schematic diagram of a bus synchronization test of a master light curtain and a slave light curtain in a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0025] Various aspects of the present invention are described in further detail below.

[0026] Unless otherwise defined or indicated, all professional and scientific terms used herein have the same meanings as those familiar to those skilled in the art. In addition, any methods and materials similar or equivalent to those described herein can be applied to the present invention.

[0027] The following is an explanation of the terms.

[0028] It is to be understood that although the terms "first", "second", etc. may be used herein to describe different elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Therefore, the first element may be referred to as the second element without departing from the teachings of the present invention.

[0029] In the present invention, the terms "comprising", "including" or "comprising" indicate that various components can be applied together in the mixture or composition of the present invention. Therefore, the term "consisting mainly of..." is included in the terms "comprising", "including" or "comprising".

[0030] Unless otherwise clearly specified and limited, the terms "connected", "connected" and "connection" in the present invention should be understood in a broad sense, for example, it can be a fixed connection, or it can be connected through an intermediary medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] For example, if an element (or component) is referred to as being on, coupled to, or connected to another element, the element may be directly formed on, coupled to, or connected to the other element, or there may be one or more intervening elements between them. In contrast, if the expressions "directly on," "directly coupled to," and "directly connected to" are used herein, then no intervening elements are indicated. Other words used to describe the relationship between elements should be similarly interpreted, such as "between" and "directly between," "attached" and "directly attached," "adjacent" and "directly adjacent," and the like.

[0032] It should also be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the drawings. The words "inner" and "outer" used refer to directions toward or away from the geometric center of a particular component, respectively. It can be understood that these terms are used here to describe the relationship of one element, layer or region relative to another element, layer or region as shown in the drawings. In addition to the orientations described in the drawings, these terms should also include other orientations of the device.

[0033] Other aspects of the present invention will be apparent to those skilled in the art in view of the disclosure herein.

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0035] It should also be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. The drawings only show the components related to the present application and are not drawn according to the number, shape and size of the components in actual implementation. The type, quantity and proportion of each component in actual implementation may be changed arbitrarily, and the component layout may also be more complicated. For example, the thickness of the components in the drawings may be exaggerated for the sake of clarity.

[0036] Example

[0037] In view of the defects of the measuring light curtain in the prior art, the present invention provides a multi-light circuit combined light curtain for measuring the measured object based on the time of flight, comprising:

[0038] At least one light curtain, each of which includes a plurality of pairs of laser transceiver units and a computing unit, each of which includes a pair of corresponding laser emitting units and laser receiving units, the laser emitting units are arranged opposite to the laser receiving units, and the laser transceiver units are in a pairing channel mode, a mirror channel mode or a TOF channel mode;

[0039] At certain moments, the emitted laser is emitted from the laser emitting unit. If the emitted laser contacts the surface of the object to be measured, the surface of the object to be measured reflects the emitted laser to form a return laser, and the laser receiving unit receives the return laser.

[0040] The calculation unit calculates one or more target values ​​simultaneously according to the emitted laser, the returned laser, the emitted laser parameters, and the returned laser parameters.

[0041] In a preferred embodiment of the present invention, the object to be measured and the multi-optical circuit combination light curtain are relatively stationary, and the target value is the distance between the light curtain and the object to be measured, the emitting laser parameter is the moment t1 when the emitting laser is emitted, and the returning laser parameter is the moment t2 when the returning laser returns to the light curtain, and the distance of the object to be measured s=0.5*(t2-t1)*c, where c is the speed of light.

[0042] In a preferred embodiment of the present invention, Figure 2 As shown, the multi-optical circuit combination light curtain includes a main control module, and the laser transceiver unit defaults to the opposite channel mode. The main control module is used to change the laser transceiver unit in the light curtain opposite to the object to be measured to the TOF mode when the emitted laser contacts the object to be measured.

[0043] In a preferred embodiment of the present invention, Figure 3 As shown, the multi-optical circuit combined light curtain also includes a mirror, which is arranged parallel to the light curtain and is used to reflect the emission laser emitted by the laser emission unit, and the laser transceiver unit is a mirror reflection unit. Preferably, the mirror is a honeycomb mirror.

[0044] In a preferred embodiment of the present invention, Figure 4 As shown, the multi-optical circuit combined light curtain includes a main light curtain and a slave light curtain which are parallel to each other, and the target value includes one or more of the distance d1 between the main light curtain and the object to be measured, the distance d2 between the slave light curtain and the object to be measured, the width D1 of the object to be measured, and the shape of the object to be measured. The measurement of each target value is carried out simultaneously, and the main light curtain and the slave light curtain work independently of each other.

[0045] Among them, MB1, ..., MB5 represent five laser emitting units, SB1, ..., SB5 represent five laser receiving units, and the TOF channel, i.e., the time of flight channel, is used to measure the object to be measured.

[0046] Preferably, the combined light curtain includes a main control module, and the laser transceiver unit defaults to the opposite channel mode. The main control module is used to change the main light curtain opposite to the object to be measured and the laser transceiver unit in the slave light curtain to TOF mode when the emitted laser contacts the object to be measured.

[0047] Preferably, the width D1 of the object to be measured = L-d1-d2, L is the distance between the main light curtain and the slave light curtain; when the target value includes the shape of the object to be measured, the light curtain scans and calculates each edge of the object to be measured (such as Figure 4 The shape of the object to be measured is obtained by modeling based on the data of each edge of the object to be measured, and the object to be measured can be in any shape.

[0048] For example, the calculation unit calculates that H1 = H2 = 3 cm, and the height of the object to be measured is 3 cm.

[0049] It should be noted that Figure 4 The combined light curtain structure and the shape of the object to be measured are only for illustration. In actual applications, the laser emitting units and laser receiving units can be of other numbers, and the arrangement method can also be other denser or sparser arrangements. The object to be measured can also be of any other form. The present invention does not limit this. Other forms of laser transceiver units and objects to be measured should also be regarded as the protection scope of the present invention.

[0050] Optionally, the object under test and the multi-light circuit combined light curtain move relative to each other, including uniform motion, non-uniform motion, linear motion, and curved motion, and the target value is the motion displacement and average motion speed of the object under test.

[0051] Preferably, the multi-optical circuit combined light curtain includes a main light curtain and a slave light curtain parallel to each other. When the target value includes the motion trajectory of the object to be measured, the distance d1 between the main light curtain and the object to be measured and the distance d2 between the slave light curtain and the object to be measured are continuously measured at each moment, and the motion trajectory of the object to be measured is restored based on the values ​​of d1 and d2 at each moment.

[0052] More specifically, when the target value includes the motion displacement and / or average motion speed of the object under test, the light curtain obtains the position A of the preset point in the object under test at the measurement start time T1 and the position B of the preset point in the object under test at the measurement end time T2, as well as the measurement duration T based on the time-of-flight TOF method, T=T2-T1, the displacement S=BA of the object under test, and the average motion speed V=S / T of the object under test.

[0053] Preferably, Figure 5A - Figure 5B As shown, it also includes a synchronization module, which controls the master light curtain and the slave light curtain to perform a double synchronization test before the measurement starts, and the double synchronization test includes an optical synchronization test ( Figure 5A ) and bus synchronization test ( Figure 5B ), the bus synchronization test further monitors the stability of the optical synchronization test. The optical synchronization test includes sequentially lighting up the laser emitting units in the main light curtain and the slave light curtain, and then sequentially turning on the laser receiving units of the main light curtain and the slave light curtain to receive the laser emitted by the laser emitting units.

[0054] More preferably, the bus synchronization test includes but is not limited to industrial buses such as RS485 and CAN.

[0055] In summary, the present invention has achieved the following effects:

[0056] The present invention provides a multi-light circuit combined light curtain for measuring an object to be measured based on time of flight, comprising: a plurality of light curtains comprising a calculation unit and a plurality of pairs of laser emitting units and a laser receiving unit, wherein at a certain moment, an emitted laser is emitted by the laser emitting unit, if the emitted laser contacts the surface of the object to be measured, the surface of the object to be measured reflects the emitted laser to form a return laser, the laser receiving unit receives the return laser, and the calculation unit calculates a target value according to the emitted laser parameter and the return laser parameter; the multi-light circuit combined light curtain proposed by the present invention has a simple structure and is simple to implement, and can directly and quickly calculate multiple target values ​​of the object to be measured at the same time through the light curtain, including one or more of the distance between the light curtain and the object to be measured, the width of the object to be measured, the shape of the object to be measured, the motion state of the object to be measured, the displacement, and the speed, and can quickly reconstruct and model the object to be measured according to the target value.

[0057] Based on this application, it should be understood by those skilled in the art that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspect described herein can be used to implement the device and / or practice the method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this device and / or practice this method.

[0058] Those skilled in the art know that, in addition to realizing the system and its various devices, modules, and units provided by the present invention in a purely computer-readable program code, it is entirely possible to realize the same functions in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system and its various devices, modules, and units provided by the present invention can be considered as a hardware component, and the devices, modules, and units included therein for realizing various functions can also be regarded as structures within the hardware component; the devices, modules, and units for realizing various functions can also be regarded as both software modules for realizing the method and structures within the hardware component.

[0059] It should be noted that the above embodiments can be freely combined as needed. The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered as the protection scope of the present invention.

[0060] All documents mentioned in the present invention are cited as references in this application, just as each document is cited as reference separately. In addition, it should be understood that after reading the above content of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the claims attached to this application.

Claims

1. A multi-light circuit combined light curtain for measuring an object to be measured based on time of flight, characterized in that: include: A plurality of light curtains, the plurality of light curtains comprising a main light curtain and a slave light curtain parallel to each other, each of the light curtains comprising a plurality of pairs of laser transceiver units and a calculation unit; Each of the laser transceiver units includes a pair of corresponding laser emitting units and laser receiving units, and the laser transceiver units are in a pairing channel mode or a TOF channel mode; when the laser transceiver unit is in a pairing channel mode, the laser emitting unit on the main light curtain and the laser receiving unit on the slave light curtain are arranged opposite to each other; at certain moments, the emitted laser is emitted by the laser emitting unit, and if the emitted laser contacts the surface of the object to be measured, the surface of the object to be measured reflects the emitted laser to form a return laser, and the laser receiving unit receives the return laser; The calculation unit calculates multiple target values ​​simultaneously according to the emitted laser, the returned laser, the emitted laser parameters, and the returned laser parameters; wherein, The combined light curtain also includes a main control module, which is used to change the main light curtain and the laser transceiver unit in the slave light curtain opposite to the object to be measured into TOF mode when the emitted laser contacts the object to be measured when the laser transceiver unit is in the opposite channel mode; The object to be measured and the multi-light circuit combined light curtain move relative to each other, including curved motion, and the target value is the motion displacement and average motion speed of the object to be measured.

2. The multi-light circuit combined light curtain for measuring the object to be measured based on time of flight according to claim 1, characterized in that: When the object to be measured and the multi-optical circuit combined light curtain are relatively still and the target value is the distance between the light curtain and the object to be measured, the emitted laser parameter is the moment t1 when the emitted laser is emitted, and the returned laser parameter is the moment t2 when the returned laser returns to the light curtain. The distance of the object to be measured s=0.5*(t2-t1)*c, where c is the speed of light.

3. The multi-light circuit combined light curtain for measuring the object to be measured based on time of flight according to claim 2, characterized in that: The multi-optical circuit combined light curtain includes a light curtain, the laser transceiver unit of the light curtain used to measure the distance of the measured object is set to the TOF channel mode, and the laser transceiver units of the remaining parts are in the opposite channel mode.

4. The multi-light circuit combined light curtain for measuring the object to be measured based on time of flight according to claim 2, characterized in that: The multi-optical circuit combined light curtain includes a main light curtain and a slave light curtain which are parallel to each other. The target value includes one or more of the distance d1 between the main light curtain and the object to be measured, the distance d2 between the slave light curtain and the object to be measured, the width D1 of the object to be measured, and the shape of the object to be measured. The measurement of each target value is carried out simultaneously, and the main light curtain and the slave light curtain work independently of each other.

5. The multi-light circuit combined light curtain for measuring the object to be measured based on time of flight according to claim 4, characterized in that: It also includes a synchronization module, which controls the main light curtain and the slave light curtain to perform a double synchronization test before the measurement starts. The double synchronization test includes an optical synchronization test and a bus synchronization test. The optical synchronization test includes sequentially lighting up the laser emitting units in the main light curtain and the slave light curtain, and then sequentially turning on the laser receiving units of the main light curtain and the slave light curtain to receive the laser emitted by the laser emitting units.

6. The multi-light circuit combined light curtain for measuring the object to be measured based on time of flight according to claim 4, characterized in that: The width D1 of the object to be measured is L-d1-d2, where L is the distance between the main light curtain and the slave light curtain. When the target value includes the shape of the object to be measured, the light curtain is scanned and calculated based on the time-of-flight TOF method, and the shape of the object to be measured is obtained based on the data modeling of each edge of the object to be measured. The object to be measured can be in any shape.

7. The multi-light circuit combined light curtain for measuring the object to be measured based on time of flight according to claim 1, characterized in that: The relative motion between the object to be measured and the multi-light circuit combined light curtain also includes uniform motion, non-uniform motion, and linear motion.

8. The multi-light circuit combined light curtain for measuring the object to be measured based on time of flight according to claim 7, characterized in that: When the target value includes the motion trajectory of the object to be measured, the distance d1 between the main light curtain and the object to be measured and the distance d2 between the slave light curtain and the object to be measured are continuously measured at each moment, and the motion trajectory of the object to be measured is restored based on the values ​​d1 and d2 at each moment.

9. The multi-light circuit combined light curtain for measuring the object to be measured based on time of flight according to claim 8, characterized in that: When the target value includes the motion displacement and / or average motion speed of the object under test, the light curtain obtains the position A of the preset point in the object under test at the measurement start time T1 and the position B of the preset point in the object under test at the measurement end time T2 based on the time-of-flight TOF method, as well as the measurement duration T, T=T2-T1, the displacement S=BA of the object under test, and the average motion speed V=S / T of the object under test.

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