Single-loop absolute encoder speed measurement and processing method and system

Abstract

The invention relates to the technical field of industrial information automation, in particular to a single-turn absolute encoder speed measurement and processing method and system, and the method comprises the steps: S1, initializing the parameters of a single-turn absolute encoder; s2, the encoder after parameter initialization continuously outputs angular positions at a fixed time interval, and the angular positions continuously output twice are differentiated to obtain an angular velocity; s3, according to the angular velocity obtained in the step S2, identifying and correcting the abnormal angular velocity at the zero-crossing position of the angular position of the encoder to obtain the corrected angular velocity; and S4, identifying and processing the outlier of the angular velocity corrected in the step S3. The invention also relates to a single-loop absolute encoder speed measurement and processing system. According to the method, the relatively smooth and accurate angular velocity can be obtained on the basis of not additionally adding hardware.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial information automation, and in particular to a speed measurement and processing method and system for a single-turn absolute encoder. Background Art

[0002] An encoder is a precision displacement measurement sensor that can convert angular displacement or linear displacement into electrical signals. The former is called a rotary encoder and the latter is called a linear encoder. Encoders are very important for systems that require precise control of position or speed, and have been widely used in CNC machine tools, robots, medical equipment, aerospace and other industrial information automation technology fields.

[0003] Rotary encoders can be roughly divided into two categories according to different characteristics: incremental encoders and absolute encoders. Incremental encoders output two orthogonal encoding pulses and zero-phase pulses. The speed and direction can be obtained by counting the two orthogonal pulses and judging the phase pulses. Its advantage is that it is easy to achieve miniaturization, but its disadvantage is that the initial positioning is prone to data loss after power failure. Absolute encoders output binary digital signals, and each angular position has a unique code. The position information will not be lost after the system is powered on and off again. It has stronger anti-interference ability and is usually used in systems with more precise position and speed requirements.

[0004] The single-turn absolute encoder has an angular measurement range of 0 to 360 degrees. When the rotation exceeds 360 degrees, the angle value returns to the origin of zero degrees. When the differential method is used to obtain the rotation speed, there is a high fluctuation in the encoder zero position, which causes the differential method to measure the speed discontinuously and inaccurately. To obtain continuous and reliable rotation speed, a gyroscope can be installed on the encoder coaxial system, but this not only increases the structure volume and weight, but also increases the additional cost, which is unacceptable in many cases.

[0005] If you want to use only a single-turn absolute encoder for speed measurement, especially when the rotating shaft system requires the encoder to pass through zero or even requires multiple turns of continuous rotation, you must consider the continuity and reliability of the speed measurement. Summary of the invention

[0006] In view of this, it is necessary to provide a single-turn absolute encoder speed measurement and processing method and system, which can obtain a relatively smooth and accurate angular velocity without adding additional hardware.

[0007] The present invention provides a single-turn absolute encoder speed measurement and processing method, the method comprising the following steps: S1, initializing the parameters of the single-turn absolute encoder; S2, the encoder after the parameters are initialized continuously outputs the angular position at a fixed time interval, and differentiates the angular positions outputted twice in succession to obtain the angular velocity; S3, according to the angular velocity obtained in step S2, identifying and correcting the abnormal angular velocity at the zero-crossing position of the encoder angular position, to obtain the corrected angular velocity; S4, identifying and processing the wild value of the corrected angular velocity in step S3.

[0008] Preferably, the step S1 comprises: Define the single-turn absolute encoder data output time interval as T; Define the angle value of the single-turn absolute encoder output in real time as , and initialized to zero, that is , the value range is ; Define the angular position of two consecutive differences in step S2 as the current angular position and the angular position at the previous moment , and initialized to zero, that is , ; Define the temporary variable of the current angular position of the single-turn absolute encoder , and initialized to zero, that is ; Initialize the signed integer data N of the differential angular velocity anomaly at the zero-crossing angular position of the single-turn absolute encoder to zero, that is, N=0; The threshold value of the abnormal differential angular velocity at the zero crossing of the angular position of the single-turn absolute encoder is defined as , and according to the maximum speed of the actual encoder used in the device ,initialization ; Define the angular velocity obtained in step S2 as , and initialized to zero, that is ; Define the angular velocity corrected in step S3 as , and initialized to zero, that is ; Define the angular velocity in step S3 The count value of continuous small wild values ​​is M, and is initialized to zero, that is, M=0; Define the angular velocity after processing in step S4 as , and initialized to zero, that is .

[0009] Preferably, step S2 comprises: Calculate the temporary variable of the current angular position ,Right now ; The angular velocity is calculated by the difference method ,Right now .

[0010] Preferably, step S3 comprises: like and , then increase the N by 1, that is, N=N+1; like and , then subtract 1 from N, that is, N=N-1; Update and correct the current angular position ,Right now ; Update and correct the angular velocity by difference method ,Right now ; Update the previous moment angular position ,Right now .

[0011] Preferably, step S4 comprises: like , then the current angular velocity For abnormal wild values, directly change the current Eliminate and update the angular velocity ,Right now ; like , and meets the conditions , then determine the current angular velocity At least isolated small outliers, the current Eliminate and update the angular velocity ,Right now , and increase the M by 1, that is, M=M+1, and then determine whether the M is greater than or equal to 3: If , then determine the current angular velocity For small outliers of the plaque, recalibrate the angular velocity , update the angular velocity ,Right now , and at the same time, the M value is set to zero, that is, M=0; like , and meets the conditions , then determine the current angular velocity is a normal value, and updates the angular velocity ,Right now , and at the same time set the M value to zero, that is, M=0.

[0012] The present invention also provides a single-turn absolute encoder speed measurement and processing system, which includes an initialization module, a differential module, a correction module, and a processing module, wherein: The initialization module is used to initialize the parameters of the single-turn absolute encoder; The differential module is used for the encoder to continuously output the angular position at a fixed time interval after the parameters are initialized, and to perform a differential operation on the angular positions outputted twice in succession to obtain the angular velocity; The correction module is used to identify and correct the abnormal angular velocity at the zero-crossing position of the encoder angular position according to the angular velocity obtained by the differential module, so as to obtain a corrected angular velocity; The processing module is used to identify and process wild values ​​of the angular velocity corrected by the correction module.

[0013] Preferably, the initialization module is specifically used for: Define the single-turn absolute encoder data output time interval as T; Define the angle value of the single-turn absolute encoder output in real time as , and initialized to zero, that is , whose value is updated by the encoder angular position output data at time interval T, and its value range is ; Define the angular position of two consecutive differentials of the differential module as the current angular position and the angular position at the previous moment , and initialized to zero, that is , ; Define the temporary variable of the current angular position of the single-turn absolute encoder , and initialized to zero, that is ; Initialize the signed integer data N of the differential angular velocity anomaly at the zero-crossing angular position of the single-turn absolute encoder to zero, that is, N=0; The threshold value of the abnormal differential angular velocity at the zero crossing of the angular position of the single-turn absolute encoder is defined as , and according to the maximum speed of the actual encoder used in the device ,initialization ; Define the angular velocity obtained by the differential module as , and initialized to zero, that is ; Define the angular velocity corrected by the correction module as , and initialized to zero, that is ; Define the angular velocity of the correction module The count value of continuous small wild values ​​is M, and is initialized to zero, that is, M=0; Define the angular velocity after processing by the processing module as , and initialized to zero, that is .

[0014] Preferably, the differential module is specifically used for: Calculate the temporary variable of the current angular position ,Right now ; The angular velocity is calculated by the difference method ,Right now .

[0015] Preferably, the correction module is specifically used for: like and , then increase the N by 1, that is, N=N+1; like and , then subtract 1 from N, that is, N=N-1; Update and correct the current angular position ,Right now ; Update and correct the angular velocity by the difference method ,Right now ; Update the previous moment angular position ,Right now .

[0016] Preferably, the processing module is specifically used for: like , then the current angular velocity For abnormal wild values, directly change the current Eliminate and update the angular velocity ,Right now ; like , and meets the conditions , then determine the current angular velocity At least isolated small outliers, the current Eliminate and update the angular velocity ,Right now , and increase the M by 1, that is, M=M+1, and then determine whether the M is greater than or equal to 3: If , then determine the current angular velocity For small outliers of the plaque, recalibrate the angular velocity , update the angular velocity ,Right now , and at the same time, the M value is set to zero, that is, M=0; like , and meets the conditions , then determine the current angular velocity is a normal value, and updates the angular velocity ,Right now , and at the same time set the M value to zero, that is, M=0.

[0017] The present application can not only accurately identify the zero-crossing state of the encoder angular position and correct the differential speed, but also identify and process the encoder noise field value, thereby obtaining a relatively smooth and accurate angular velocity without adding additional hardware. The method is widely applicable to the absolute encoder differential speed measurement in the field of industrial information automation technology, especially to the continuous differential speed measurement of a single-turn absolute encoder. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flow chart of the speed measurement and processing method of the single-turn absolute encoder of the present invention; Figure 2 A schematic flow chart of a single-turn absolute encoder speed measurement and processing method provided in an embodiment of the present invention; Figure 3 The hardware architecture diagram of the single-turn absolute encoder speed measurement and processing system of the present invention. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical scheme and advantages of the invention clearer, the invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the invention and do not constitute a limitation to the invention. Similar components in different embodiments use associated similar component numbers. In the following embodiments, many detailed descriptions are to enable the invention to be better understood. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other components, materials, and methods. In some cases, some operations related to the invention are not shown or described in the specification, in order to avoid the core part of the invention being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations according to the description in the specification and the general technical knowledge in the art.

[0020] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to form various implementation methods. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a necessary sequence, unless otherwise specified that a certain sequence must be followed.

[0021] In the description of the invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the invention, unless otherwise specified, the meaning of "multiple" is two or more.

[0022] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0023] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0024] See also Figure 1 The figure is a flowchart of a preferred embodiment of the single-turn absolute encoder speed measurement and processing method of the present invention. Figure 2 : Step S1, initializing the parameters of the single-turn absolute encoder. Specifically: Define the single-turn absolute encoder data output time interval as T; Define the angle value of the single-turn absolute encoder output in real time as , and initialized to zero, that is , whose value is updated by the encoder angular position output data at time interval T, and its value range is ; Define the angular position of two consecutive differences in step S2 as the current angular position and the angular position at the previous moment , and initialized to zero, that is , ; Define the temporary variable of the current angular position of the single-turn absolute encoder , and initialized to zero, that is ; Initialize the signed integer data N of the differential angular velocity anomaly at the zero-crossing angular position of the single-turn absolute encoder to zero, that is, N=0; The threshold value of the abnormal differential angular velocity at the zero crossing of the angular position of the single-turn absolute encoder is defined as , and according to the maximum speed of the actual encoder used in the device ,initialization ; Define the angular velocity obtained in step S2 as , and initialized to zero, that is ; Define the angular velocity corrected in step S3 as , and initialized to zero, that is ; Define the angular velocity in step S3 The count value of continuous small wild values ​​is M, and is initialized to zero, that is, M=0; Define the angular velocity after processing in step S4 as , and initialized to zero, that is .

[0025] Step S2, the encoder after initialization of parameters continuously outputs the angular position at a fixed time interval, and the angular position outputted twice in succession is differentiated to obtain the angular velocity. Specifically: Calculate the temporary variable of the current angular position ,Right now ; The angular velocity is calculated by the difference method ,Right now .

[0026] Step S3, based on the angular velocity obtained in step S2, identifying and correcting the abnormal angular velocity at the zero-crossing position of the encoder angular position, to obtain a corrected angular velocity. Specifically: If satisfied and If the condition is met, then N is increased by 1, that is, N=N+1; If satisfied and If the condition is met, then the N is subtracted by 1, that is, N=N-1; Update and correct the current angular position ,Right now ; Update and correct the angular velocity by the difference method ,Right now ; Update the previous moment angular position ,Right now .

[0027] Step S4, identifying and processing the wild value of the angular velocity corrected in step S3. Specifically: like , then the current angular velocity For abnormal wild values, directly change the current Eliminate and update the angular velocity ,Right now ; like , and meets the conditions , then determine the current angular velocity At least isolated small outliers, the current Eliminate and update the angular velocity ,Right now , and increase the M by 1, that is, M=M+1, and then determine whether the M is greater than or equal to 3: If , then determine the current angular velocity For small outliers of the plaque, recalibrate the angular velocity , update the angular velocity ,Right now , and at the same time, the M value is set to zero, that is, M=0; like , and meets the conditions , then determine the current angular velocity is a normal value, and updates the angular velocity ,Right now , and at the same time set the M value to zero, that is, M=0.

[0028] See also Figure 3 , is a hardware architecture diagram of a single-turn absolute encoder speed measurement and processing system 10 of the present invention. The system includes: an initialization module 101, a difference module 102, a correction module 103, and a processing module 104. Among them: The initialization module 101 is used to initialize the parameters of the single-turn absolute encoder. Specifically: Define the single-turn absolute encoder data output time interval as T; Define the angle value of the single-turn absolute encoder output in real time as , and initialized to zero, that is , whose value is updated by the encoder angular position output data at time interval T, and its value range is ; Define the angular position of two consecutive differences of the difference module 102 as the current angular position and the angular position at the previous moment , and initialized to zero, that is , ; Define the temporary variable of the current angular position of the single-turn absolute encoder , and initialized to zero, that is ; Initialize the signed integer data N of the differential angular velocity anomaly at the zero-crossing angular position of the single-turn absolute encoder to zero, that is, N=0; The threshold value of the abnormal differential angular velocity at the zero crossing of the angular position of the single-turn absolute encoder is defined as , and according to the maximum speed of the actual encoder used in the device ,initialization ; The angular velocity obtained by the differential module 102 is defined as , and initialized to zero, that is ; The angular velocity corrected by the correction module 103 is defined as , and initialized to zero, that is ; Define the angular velocity of the correction module 103 The count value of continuous small wild values ​​is M, and is initialized to zero, that is, M=0; The angular velocity after processing by the processing module 104 is defined as , and initialized to zero, that is .

[0029] The difference module 102 is used to differentiate the angular positions outputted two times continuously after the encoder outputs the angular position at a fixed time interval after the parameters are initialized, so as to obtain the angular velocity. Specifically: The difference module 102 calculates the temporary variable of the angular position at the current moment ,Right now ; The difference module 102 calculates the angular velocity by a difference method. ,Right now .

[0030] The correction module 103 is used to identify and correct the abnormal angular velocity at the zero-crossing position of the encoder angular position according to the angular velocity obtained by the difference module 102, and obtain the corrected angular velocity. Specifically: If satisfied and If the condition is met, the correction module 103 increases the N by 1, that is, N=N+1; If satisfied and If the condition is met, the correction module 103 subtracts 1 from N, that is, N=N-1; Correction module 103 updates and corrects the current angular position ,Right now ; The correction module 103 updates and corrects the angular velocity by using the difference method ,Right now ; Correction module 103 updates the angular position at the previous moment ,Right now .

[0031] The processing module 104 is used to identify and process the wild value of the angular velocity corrected by the correction module 103. Specifically: like , then the current angular velocity is an abnormal wild value, the processing module 104 directly converts the current Eliminate and update the angular velocity ,Right now ; like , and meets the conditions , then determine the current angular velocity At least an isolated tiny wild value, the processing module 104 Eliminate and update the angular velocity ,Right now , and increase the M by 1, that is, M=M+1, and then determine whether the M is greater than or equal to 3: If , then determine the current angular velocity For small outliers of the plaque, recalibrate the angular velocity , update the angular velocity ,Right now , and at the same time, the M value is set to zero, that is, M=0; like , and meets the conditions , then determine the current angular velocity is a normal value, the processing module 104 updates the angular velocity ,Right now , and at the same time set the M value to zero, that is, M=0.

[0032] Although the present invention has been described with reference to the current preferred embodiments, those skilled in the art should understand that the above-mentioned preferred embodiments are only used to illustrate the present invention and are not used to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the scope of protection of the present invention.

Claims

1. A single-turn absolute encoder speed measurement and processing method, characterized in that: The method comprises the following steps: S1, initialize the parameters of the single-turn absolute encoder; S2, the encoder after initialization of parameters continuously outputs the angular position at a fixed time interval, and the angular position outputted twice in succession is differentiated to obtain the angular velocity; S3, according to the angular velocity obtained in step S2, identifying and correcting the abnormal angular velocity at the zero-crossing position of the encoder angular position to obtain a corrected angular velocity; S4, identifying and processing the wild value of the angular velocity corrected in step S3.

2. The single-turn absolute encoder speed measurement and processing method according to claim 1, characterized in that: The step S1 comprises: Define the single-turn absolute encoder data output time interval as T; Define the angle value of the single-turn absolute encoder output in real time as , and initialized to zero, that is , the value range is ; Define the angular position of two consecutive differences in step S2 as the current angular position and the angular position at the previous moment , and initialized to zero, that is , ; Define the temporary variable of the current angular position of the single-turn absolute encoder , and initialized to zero, that is ; Initialize the signed integer data N of the differential angular velocity anomaly at the zero-crossing angular position of the single-turn absolute encoder to zero, that is, N=0; The threshold value of the abnormal differential angular velocity at the zero crossing of the angular position of the single-turn absolute encoder is defined as , and according to the maximum speed of the actual encoder used in the device ,initialization ; Define the angular velocity obtained in step S2 as , and initialized to zero, that is ; Define the angular velocity corrected in step S3 as , and initialized to zero, that is ; Define the angular velocity in step S3 The count value of continuous small wild values ​​is M, and is initialized to zero, that is, M=0; Define the angular velocity after processing in step S4 as , and initialized to zero, that is .

3. The single-turn absolute encoder speed measurement and processing method as claimed in claim 2, characterized in that: The step S2 comprises: Calculate the temporary variable of the current angular position ,Right now ; The angular velocity is calculated by the difference method ,Right now .

4. The single-turn absolute encoder speed measurement and processing method as claimed in claim 3, characterized in that: The step S3 comprises: like and , then increase the N by 1, that is, N=N+1; like and , then subtract 1 from N, that is, N=N-1; Update and correct the current angular position ,Right now ; Update and correct the angular velocity by difference method ,Right now ; Update the previous moment angular position ,Right now .

5. The single-turn absolute encoder speed measurement and processing method as claimed in claim 4, characterized in that: The step S4 comprises: like , then the current angular velocity For abnormal wild values, directly change the current Eliminate and update the angular velocity ,Right now ; like , and meets the conditions , then determine the current angular velocity At least isolated small outliers, the current Eliminate and update the angular velocity ,Right now , and increase the M by 1, that is, M=M+1, and then determine whether the M is greater than or equal to 3: If , then determine the current angular velocity For small outliers of the plaque, recalibrate the angular velocity , update the angular velocity ,Right now , and at the same time, the M value is set to zero, that is, M=0; like , and meets the conditions , then determine the current angular velocity is a normal value, and updates the angular velocity ,Right now , and at the same time set the M value to zero, that is, M=0.

6. A single-turn absolute encoder speed measurement and processing system, characterized in that: The system includes an initialization module, a difference module, a correction module, and a processing module, wherein: The initialization module is used to initialize the parameters of the single-turn absolute encoder; The differential module is used for the encoder to continuously output the angular position at a fixed time interval after the parameters are initialized, and to perform a differential operation on the angular positions outputted twice in succession to obtain the angular velocity; The correction module is used to identify and correct the abnormal angular velocity at the zero-crossing position of the encoder angular position according to the angular velocity obtained by the differential module, so as to obtain a corrected angular velocity; The processing module is used to identify and process wild values ​​of the angular velocity corrected by the correction module.

7. The single-turn absolute encoder speed measurement and processing system as claimed in claim 6, characterized in that: The initialization module is specifically used for: Define the single-turn absolute encoder data output time interval as T; Define the angle value of the single-turn absolute encoder output in real time as , and initialized to zero, that is , whose value is updated by the encoder angular position output data at time interval T, and its value range is ; Define the angular position of two consecutive differentials of the differential module as the current angular position and the angular position at the previous moment , and initialized to zero, that is , ; Define the temporary variable of the current angular position of the single-turn absolute encoder , and initialized to zero, that is ; Initialize the signed integer data N of the differential angular velocity anomaly at the zero-crossing angular position of the single-turn absolute encoder to zero, that is, N=0; The threshold value of the abnormal differential angular velocity at the zero crossing of the angular position of the single-turn absolute encoder is defined as , and according to the maximum speed of the actual encoder used in the device ,initialization ; Define the angular velocity obtained by the differential module as , and initialized to zero, that is ; Define the angular velocity corrected by the correction module as , and initialized to zero, that is ; Define the angular velocity of the correction module The count value of continuous small wild values ​​is M, and is initialized to zero, that is, M=0; Define the angular velocity after processing by the processing module as , and initialized to zero, that is .

8. The single-turn absolute encoder speed measurement and processing system according to claim 7, characterized in that: The differential module is specifically used for: Calculate the temporary variable of the current angular position ,Right now ; The angular velocity is calculated by the difference method ,Right now .

9. The single-turn absolute encoder speed measurement and processing system as claimed in claim 8, characterized in that: The correction module is specifically used for: like and , then increase the N by 1, that is, N=N+1; like and , then subtract 1 from N, that is, N=N-1; Update and correct the current angular position ,Right now ; Update and correct the angular velocity by difference method ,Right now ; Update the previous moment angular position ,Right now .

10. The single-turn absolute encoder speed measurement and processing system according to claim 9, characterized in that: The processing module is specifically used for: like , then the current angular velocity For abnormal wild values, directly change the current Eliminate and update the angular velocity ,Right now ; like , and meets the conditions , then determine the current angular velocity At least isolated small outliers, the current Eliminate and update the angular velocity ,Right now , and increase the M by 1, that is, M=M+1, and then determine whether the M is greater than or equal to 3: If , then determine the current angular velocity For small outliers of the plaque, recalibrate the angular velocity , update the angular velocity ,Right now , and at the same time, the M value is set to zero, that is, M=0; like , and meets the conditions , then determine the current angular velocity is a normal value, and updates the angular velocity ,Right now , and at the same time set the M value to zero, that is, M=0.

Images