Proximity Detection Method, Proximity Sensor and Manipulator

Abstract

The present invention provides a proximity detection method, a proximity sensor and a robotic arm. The method includes: controlling a piezoelectric crystal transducer to output a square wave acoustic signal from a first I / O port; when a return signal is received, controlling the piezoelectric crystal transducer to output a high-level acoustic signal from a second I / O port; calculating the distance between the proximity position sensor and the target object based on the duration from the emission of the high-level acoustic signal to the reception of the return signal at the receiving end as the test distance; obtaining test distance and actual distance data detected at different positions in the above manner to form multiple sets of distance data; calculating a correction parameter based on the multiple sets of distance data; and correcting the test distance according to the correction parameter during actual detection. In the present invention, different acoustic signals are sent through different ports, thereby improving the accuracy of distance detection. And during actual application, the test distance is corrected according to the correction parameter, further improving the accuracy of the proximity position sensor detection.

Description

Technical Field

[0001] The present invention relates to the field of detection technologies, and particularly to a close-range detection method, a close-range sensor, and a robotic arm. Background Art

[0002] Distance sensors operate based on various principles and can be mainly classified into two categories: contact type and non-contact type. Contact sensors include travel switches and two-dimensional matrix position sensors, etc. Travel switches are controlled by physical contact actions and are widely used in the axial movement control of machining centers. Two-dimensional matrix position sensors are used to detect the contact positions of objects. Non-contact sensors include electromagnetic, photoelectric, eddy current, capacitive, reed switches, Hall type, etc. They emit action signals when an object approaches a set distance without direct contact with the object. For example, photoelectric position sensors detect the position of an object by emitting and receiving light. For some application scenarios, such as motor control and robotic arm control, contact sensors are not applicable, and non-contact sensors are generally used.

[0003] However, current non-contact sensors can interfere with position sensors in environments with strong interference, resulting in low accuracy, easy misjudgment, and a decline in the performance of position sensors. Summary of the Invention

[0004] To solve the above technical problems, a first objective of the present invention is to propose a close-range detection method.

[0005] A second objective of the present invention is to propose a close-range sensor.

[0006] A third objective of the present invention is to propose a robotic arm.

[0007] The technical solution adopted by the present invention is as follows:

[0008] An embodiment of the first aspect of the present invention provides a proximity detection method, including the following steps: setting a proximity position sensor and a target object in a test environment; controlling the piezoelectric crystal transducer of the proximity position sensor to output a square wave acoustic signal from a first I / O (input / output) port, and the square wave acoustic signal automatically returns to the receiving end of the proximity position sensor after encountering the target object; when the receiving end receives the returned signal, controlling the piezoelectric crystal transducer to output a high-level acoustic signal from a second I / O port, and the high-level acoustic signal automatically returns to the receiving end of the proximity position sensor after encountering the target object; calculating the distance between the proximity position sensor and the target object as the test distance according to the duration t of the high-level acoustic signal from being emitted to the receiving end receiving the returned signal, and obtaining the actual distance between the current proximity position sensor and the target object; obtaining the test distance and actual distance data of the proximity position sensor and the target object at different positions in the above manner, forming multiple sets of distance data and storing them; calculating the correction parameter of the proximity position sensor according to the multiple sets of distance data; in actual detection, correcting the test distance of the proximity position sensor according to the correction parameter to generate the detection result of the proximity position sensor.

[0009] The proximity detection method proposed above in the present invention may further have the following additional technical features:

[0010] According to an embodiment of the present invention, calculating the correction parameter of the proximity position sensor according to multiple sets of distance data specifically includes: calculating the absolute value of the difference between multiple sets of the test distance and actual distance data; forming a distance matrix A according to the absolute value of the difference, the distance matrix A includes m rows and n columns, and m and n are positive integers; randomly selecting any column in the distance matrix A as a reference column a0, calculating the Euclidean distance between the remaining columns and the reference column a0, and forming a loss matrix C according to the Euclidean distance; calculating a correction distance P according to the loss matrix C, where the correction distance is an element of matrix C, and n is a positive integer; obtaining the correction parameter of the proximity position sensor according to the correction distance.

[0011] According to an embodiment of the present invention, the square wave acoustic signal output by the piezoelectric crystal transducer includes: a square wave acoustic signal of 40 kHz with 8 cycles.

[0012] According to an embodiment of the present invention, test distance = (duration t of the high-level acoustic signal * 340 m / s) / 2.

[0013] A second aspect embodiment of the present invention provides a proximity sensor, comprising: a piezoelectric crystal transducer for outputting a square wave acoustic signal and a high-level acoustic signal; a controller for controlling the piezoelectric crystal transducer of the proximity position sensor to output a square wave acoustic signal from a first I / O port. The square wave acoustic signal automatically returns to the receiving end of the proximity position sensor after encountering a target object. When the receiving end receives the return signal, it controls the piezoelectric crystal transducer to output a high-level acoustic signal from a second I / O port. The high-level acoustic signal automatically returns to the receiving end of the proximity position sensor after encountering a target object. The controller is further configured to: obtain and store the test distances and actual distance data of the proximity position sensor and the target object at different positions in the above manner, form and store multiple sets of distance data, calculate correction parameters of the proximity position sensor according to the multiple sets of distance data, and in actual detection, correct the test distance of the proximity position sensor according to the correction parameters to generate the detection result of the proximity position sensor.

[0014] The proximity sensor proposed above in the present invention may further have the following additional technical features:

[0015] According to an embodiment of the present invention, the controller is specifically configured to: calculate the absolute value of the difference between multiple sets of the test distance and actual distance data; form a distance matrix A according to the absolute value of the difference. The distance matrix A includes m rows and n columns, where m and n are positive integers; randomly select any column in the distance matrix A as a reference column a0, calculate the Euclidean distance between the remaining columns and the reference column a0, and form a loss matrix C according to the Euclidean distance; calculate a correction distance P according to the loss matrix, where the correction distance is an element of matrix C, and n is a positive integer; obtain the correction parameters of the proximity position sensor according to the correction distance.

[0016] According to an embodiment of the present invention, the square wave acoustic signal output by the controller controlling the piezoelectric crystal transducer includes: a square wave acoustic signal of 40 kHz with 8 cycles.

[0017] According to an embodiment of the present invention, the controller specifically obtains the test distance according to the following formula: test distance = (high-level acoustic signal duration t * 340 m / s) / 2.

[0018] A third aspect embodiment of the present invention provides a robotic arm, comprising the proximity sensor described in the second aspect embodiment of the present invention.

[0019] Advantages of the present invention:

[0020] In the present invention, different acoustic wave signals are sent through different ports, thereby improving the accuracy of distance detection. During actual application, the measured distance is corrected according to the correction parameters, further improving the accuracy of the short-distance position sensor detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a flowchart of a short-distance detection method according to an embodiment of the present invention;

[0022] Figure 2 is a flowchart of a short-distance detection method according to another embodiment of the present invention;

[0023] Figure 3 is a block schematic diagram of the structure of a short-distance sensor according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0025] Figure 1 is a flowchart of a short-distance detection method according to an embodiment of the present invention, as Figure 1 shown, the method includes the following steps:

[0026] S1. Set a short-distance position sensor and a target object in the test environment.

[0027] S2. Control the piezoelectric crystal transducer of the short-distance position sensor to output a square wave acoustic wave signal from the first I / O port. After the square wave acoustic wave signal encounters the target object, it automatically returns to the receiving end of the short-distance position sensor.

[0028] S3. When the receiving end receives the return signal, control the piezoelectric crystal transducer to output a high-level acoustic wave signal from the second I / O port. After the high-level acoustic wave signal encounters the target object, it automatically returns to the receiving end of the short-distance position sensor.

[0029] S4. Calculate the distance between the short-distance position sensor and the target object as the measured distance according to the duration t of the high-level acoustic wave signal from being emitted to the receiving end receiving the return signal, and obtain the actual distance between the current short-distance position sensor and the target object.

[0030] Specifically, control the piezoelectric crystal transducer of the proximity position sensor to output a square wave acoustic signal from the first I / O port. After the square wave acoustic signal encounters the target object, it will automatically return to the receiving end of the proximity position sensor. After receiving the returned square wave signal, control the piezoelectric crystal transducer to output a high-level acoustic signal from the second I / O port. After the high-level acoustic signal encounters the target object, it will automatically return to the receiving end of the proximity position sensor. Calculate the distance between the proximity position sensor and the target object based on the duration t of the high-level acoustic signal as the test distance. The duration t of the high-level acoustic signal is the time from transmission to return of the high-level acoustic signal. For the actual distance between the front proximity position sensor and the target object, this parameter is a known quantity in the test environment.

[0031] In an embodiment of the present invention, the square wave acoustic signal output by the piezoelectric crystal transducer includes: a square wave acoustic signal of 40 kHz for 8 cycles. That is to say, it is sufficient to output the square wave acoustic signal from the first I / O port for 8 cycles to ensure the detection range. If it is a square wave acoustic signal of 40 kHz for 8 cycles, target objects within a range of 5 cm can be detected.

[0032] In an embodiment of the present invention, the test distance = (t * 340 m / s) / 2, where t is the duration of the high-level acoustic signal.

[0033] Thus, the present invention uses two ports to send and receive different acoustic signals, which can avoid interference between the two signals and prevent the problem of inaccurate distance detection caused by including the high level returned by the square wave acoustic signal in the duration of the high-level acoustic signal.

[0034] S5. Use the above method to obtain the test distance and actual distance data of the proximity position sensor and the target object at different positions, form multiple sets of distance data, and store them.

[0035] Specifically, within the set range, by changing the positions of the proximity position sensor and / or the target object, use the above method to obtain the test distance and actual distance data of the proximity position sensor and the target object at different positions, thereby forming multiple sets of distance data and storing them. The number of sets can be set in advance, for example, 500 sets.

[0036] S6. Calculate the correction parameter of the proximity position sensor according to multiple sets of distance data.

[0037] According to an embodiment of the present invention, as Figure 2 shown, calculating the correction parameter of the proximity position sensor according to multiple sets of distance data specifically includes:

[0038] S61. Calculate the absolute value of the difference between multiple sets of test distance and actual distance data.

[0039] S62. Form a distance matrix A based on the absolute value of the difference. The distance matrix A includes m rows and n columns, where m and n are positive integers.

[0040] Specifically, form the distance matrix A with the calculated absolute value of the difference. A includes m rows and n columns. m and n can be set in advance according to the number of groups of distance data.

[0041] S63. Randomly select any column in the distance matrix A as the reference column a0, calculate the Euclidean distance c between the remaining columns and the reference column a0, and form a loss matrix C based on the Euclidean distance.

[0042] C = (c1, c2,..., c n-1 ).

[0043] S64. Calculate the correction distance P based on the loss matrix C, where the correction distance c n-1 is an element of the matrix C, and n is a positive integer.

[0044] S65. Obtain the correction parameters of the short-range position sensor according to the correction distance.

[0045] Specifically, use the calculated correction distance as the correction parameter of the short-range position sensor.

[0046] S7. In actual detection, correct the test distance of the short-range position sensor according to the correction parameter to generate the detection result of the short-range position sensor.

[0047] Specifically, in the actual application of the short-range position sensor, control the piezoelectric crystal transducer of the short-range position sensor to output a square-wave acoustic signal from the first I / O port. The square-wave acoustic signal will automatically return to the receiving end of the short-range position sensor after encountering the target object. After receiving the returned square-wave signal, control the piezoelectric crystal transducer to output a high-level acoustic signal from the second I / O port. The high-level acoustic signal will automatically return to the receiving end of the short-range position sensor after encountering the target object. Calculate the distance between the short-range position sensor and the target object according to the duration t of the high-level acoustic signal. Since the acoustic signal will be refracted, scattered, or reflected multiple times during transmission, resulting in a longer received return time and a larger measurement result, therefore, in the present invention, after measuring the distance, subtract the above correction parameter from the distance to overcome the influence of the environment. Thus, in the present invention, different acoustic signals are sent through different ports, which can improve the accuracy of distance detection, and the test distance is corrected according to the correction parameter during actual application, further improving the accuracy of the short-range position sensor detection.

[0048] In summary, according to the near - distance detection method of the embodiments of the present invention, different acoustic wave signals are sent through different ports, thereby improving the accuracy of distance detection. And during actual application, the test distance is corrected according to the correction parameter, further improving the accuracy of the near - distance position sensor detection.

[0049] In addition, the present invention also provides a near - distance sensor. Since the near - distance sensor of the present invention adopts the above - mentioned near - distance detection method, for details not disclosed in the product embodiments, reference can be made to the above - mentioned method embodiments, and they will not be elaborated herein.

[0050] Figure 3 is a schematic block diagram of the structure of a near - distance sensor according to an embodiment of the present invention, as Figure 3 shown. The near - distance sensor includes: a piezoelectric crystal transducer and a controller.

[0051] Among them, the piezoelectric crystal transducer is used to output a square - wave acoustic wave signal and a high - level acoustic wave signal; the controller is used to control the piezoelectric crystal transducer of the near - distance position sensor to output a square - wave acoustic wave signal from the first I / O port. After the square - wave acoustic wave signal encounters a target object, it automatically returns to the receiving end of the near - distance position sensor. When the receiving end receives the return signal, it controls the piezoelectric crystal transducer to output a high - level acoustic wave signal from the second I / O port. After the high - level acoustic wave signal encounters a target object, it automatically returns to the receiving end of the near - distance position sensor; the above method is used to obtain the test distances and actual distance data between the near - distance position sensor and the target object at different positions and store them to form and store multiple groups of distance data, and calculate the correction parameter of the near - distance position sensor according to the multiple groups of distance data. And during actual detection, the test distance of the near - distance position sensor is corrected according to the correction parameter to generate the detection result of the near - distance position sensor.

[0052] According to an embodiment of the present invention, the controller is specifically used for: calculating the absolute value of the difference between multiple groups of test distances and actual distance data; forming a distance matrix A according to the absolute value of the difference. The distance matrix A includes m rows and n columns, where m and n are positive integers; randomly selecting any column in the distance matrix A as the reference column a0, calculating the Euclidean distance between the remaining columns and the reference column a0, and forming a loss matrix C according to the Euclidean distance; calculating a correction distance P according to the loss matrix, where the correction distance c n-1 is an element of the matrix C, and n is a positive integer; obtaining the correction parameter of the near - distance position sensor according to the correction distance.

[0053] According to an embodiment of the present invention, the square - wave acoustic wave signal controlled by the controller to be output by the piezoelectric crystal transducer includes: a 40 - khz square - wave acoustic wave signal with 8 cycles.

[0054] According to an embodiment of the present invention, the controller specifically obtains the test distance according to the following formula: test distance = (duration t of the high-level acoustic wave signal * 340 m / s) / 2.

[0055] The proximity sensor according to an embodiment of the present invention sends different acoustic wave signals through different ports, thereby improving the accuracy of distance detection, and correcting the test distance according to the correction parameter during actual application, further improving the accuracy of the proximity position sensor detection.

[0056] In addition, the present invention also provides a robotic arm including the proximity sensor described above in the present invention.

[0057] The robotic arm according to an embodiment of the present invention sends different acoustic wave signals through different ports by means of the above proximity sensor, thereby improving the accuracy of distance detection, and correcting the test distance according to the correction parameter during actual application, further improving the accuracy of the proximity position sensor detection, and thus realizing the stable control of the robotic arm.

[0058] In the description of this specification, the descriptions with reference to the terms "an embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without conflict, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0059] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0060] Any process or method description represented in a flowchart or otherwise described herein can be understood to represent a module, segment, or portion of code including one or more executable instructions for implementing a customized logic function or process, and the scope of the preferred embodiments of the present invention includes additional implementations, where functions may be executed not in the order shown or discussed, including in a substantially simultaneous manner according to the functions involved or in a reverse order, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0061] The logic and / or steps represented in a flowchart or otherwise described herein, for example, can be considered a sequenced list of executable instructions for implementing a logical function, and can be embodied specifically in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection having one or more wires (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable medium on which the program can be printed, as the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpretation, or otherwise processing as appropriate, and then stored in a computer memory.

[0062] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one of the following techniques known in the art or a combination thereof can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0063] Those of ordinary skill in the art can understand that all or part of the steps carried out in implementing the above-described embodiment methods can be completed by a program instructing relevant hardware. The said program can be stored in a computer-readable storage medium, and when executed, it includes one or a combination of the steps of the method embodiment.

[0064] In addition, in each embodiment of the present invention, each functional unit can be integrated in a processing module, or each unit can exist physically alone, or two or more units can be integrated in a module. The above-mentioned integrated module can be implemented in the form of hardware or in the form of a software functional module. When the above-mentioned integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0065] The above-mentioned storage medium can be a read-only memory, a magnetic disk or an optical disc, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A close-range detection method, characterized in that: The following steps are involved: Setting up the close-range position sensor and target object in the test environment; Controlling the piezoelectric crystal transducer of the short-distance position sensor to output a square wave acoustic signal from the first I / O port, wherein the square wave acoustic signal automatically returns to the receiving end of the short-distance position sensor after encountering a target object; When the receiving end receives the return signal, the piezoelectric crystal transducer is controlled to output a high-level sound wave signal from the second I / O port, and the high-level sound wave signal automatically returns to the receiving end of the short-range position sensor after encountering the target object; Calculate the distance between the short-range position sensor and the target object as the test distance according to the duration t from the emission of the high-level sound wave signal to the receipt of the return signal at the receiving end, and obtain the actual distance between the current short-range position sensor and the target object; The above method is used to obtain the test distance and actual distance data of the short-range position sensor and the target object at different positions, and multiple sets of distance data are formed and stored; Calculate correction parameters of a short-range position sensor based on multiple sets of distance data; In actual detection, the test distance of the short-distance position sensor is corrected according to the correction parameter to generate the detection result of the short-distance position sensor.

2. The close-range detection method according to claim 1, characterized in that: Calculate the correction parameters of the short-range position sensor based on multiple sets of distance data, including: Calculating the absolute values ​​of the differences between the test distances and the actual distance data of the plurality of groups; Form a distance matrix A according to the absolute values ​​of the differences, wherein the distance matrix A includes m rows and n columns, and m and n are positive integers; Randomly select any column in the distance matrix A as a reference column a0, calculate the Euclidean distances between the remaining columns and the reference column a0, and form a loss matrix C according to the Euclidean distances; The corrected distance P is calculated according to the loss matrix C, where the corrected distance , c n-1 is the element of matrix C, n is a positive integer; A correction parameter of the short-range position sensor is obtained according to the correction distance.

3. The close-range detection method according to claim 1, characterized in that: The square wave sound wave signal output by the piezoelectric crystal transducer includes: 8 cycles of 40 kHz square wave sound wave signal.

4. The close-range detection method according to claim 1, characterized in that: Test distance = (t*340m / s) / 2, t is the duration of the high-level sound wave signal.

5. A proximity sensor, characterized in that: include: A piezoelectric crystal transducer, wherein the piezoelectric crystal transducer is used to output a square wave sound wave signal and a high level sound wave signal; A controller, the controller is used to control the piezoelectric crystal transducer to output a square wave sound wave signal from a first I / O port, the square wave sound wave signal automatically returns to a receiving end of the short-distance position sensor after encountering a target object, and when the receiving end receives the return signal, the controller controls the piezoelectric crystal transducer to output a high-level sound wave signal from a second I / O port, the high-level sound wave signal automatically returns to the receiving end of the short-distance position sensor after encountering a target object; The controller is also used to: obtain and store the test distance and actual distance data of the short-range position sensor and the target object at different positions in the above manner, form and store multiple sets of distance data, and calculate correction parameters of the short-range position sensor based on the multiple sets of distance data; and in actual detection, correct the test distance of the short-range position sensor according to the correction parameters to generate the detection result of the short-range position sensor.

6. The proximity sensor according to claim 5, characterized in that: The controller is specifically used for: Calculating the absolute values ​​of the differences between the test distances and the actual distance data of the plurality of groups; Form a distance matrix A according to the absolute values ​​of the differences, wherein the distance matrix A includes m rows and n columns, and m and n are positive integers; Randomly select any column in the distance matrix A as a reference column a0, calculate the Euclidean distances between the remaining columns and the reference column a0, and form a loss matrix C according to the Euclidean distances; The corrected distance P is calculated according to the loss matrix, where the corrected distance , c n-1 is the element of matrix C, n is a positive integer; A correction parameter of the short-range position sensor is obtained according to the correction distance.

7. The proximity sensor according to claim 5, characterized in that: The controller controls the piezoelectric crystal transducer to output a square wave sound signal including: 8 cycles of a 40 kHz square wave sound signal.

8. The proximity sensor according to claim 5, characterized in that: The controller specifically obtains the test distance according to the following formula: Test distance = (t*340m / s) / 2, t is the duration of the high-level sound wave signal.

9. A robotic arm, characterized in that: Comprising a proximity sensor according to any one of claims 5-8.

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