阅读说明：本技术 一种卫星用光电编码器单点可靠性冗余方法 (Single-point reliability redundancy method of photoelectric encoder for satellite ) 是由 孙丹峰 申友涛 魏新生 周承豫 裴堃 于 2019-09-11 设计创作，主要内容包括：一种卫星用光电编码器单点可靠性冗余方法,计算绝对角度数据、增量角度数据和中精码增量数据,如果绝对角度数据等于增量角度数据,则光电编码器输出绝对角度数据,如果是因为精码通道异常引起绝对角度数据不等于增量角度数据,则光电编码器输出中精码增量数据,如果是因为粗码通道或中精码通道异常引起绝对角度数据不等于增量角度数据,则光电编码器输出增量角度数据。本发明使绝对式光电编码器具备内部任意的光电管及其信号通路失效时绝对模式自主切换为增量模式的功能,实现卫星用光电编码器单点可靠性冗余,使产品可靠性得到提升。(A single-point reliability redundancy method for a photoelectric encoder for a satellite calculates absolute angle data, incremental angle data and precise code incremental data, if the absolute angle data is equal to the incremental angle data, the photoelectric encoder outputs the absolute angle data, if the absolute angle data is not equal to the incremental angle data due to the abnormity of a precise code channel, the photoelectric encoder outputs medium precise code incremental data, and if the absolute angle data is not equal to the incremental angle data due to the abnormity of a coarse code channel or a medium precise code channel, the photoelectric encoder outputs the incremental angle data. The absolute photoelectric encoder has the function of automatically switching the absolute mode into the incremental mode when any internal photoelectric tube and a signal path thereof fail, realizes single-point reliability redundancy of the photoelectric encoder for the satellite, and improves the reliability of products.)

1. A single-point reliability redundancy method for a photoelectric encoder for a satellite is characterized by comprising the following steps: calculating absolute angle data, incremental angle data and precise code incremental data, and if the absolute angle data is equal to the incremental angle data, outputting the absolute angle data by the photoelectric encoder; if the absolute angle data is not equal to the incremental angle data due to the abnormal fine code channel, outputting the intermediate fine code incremental data by the photoelectric encoder; and if the absolute angle data is not equal to the incremental angle data due to the abnormity of the coarse code channel or the medium-fine code channel, the photoelectric encoder outputs the incremental angle data.

2. The method for single-point reliability redundancy of a photoelectric encoder for a satellite of claim 1, wherein the absolute angle data is binary data obtained by superimposing a coarse code, a medium-fine code and a fine code after photoelectric conversion of a position angle after signal shaping processing.

3. The method of single point reliability redundancy in a satellite based optical-electrical encoder of claim 1, wherein the incremental angle data is obtained by incremental accumulation of the fine code signal data.

4. The single-point reliability redundancy method for the photoelectric encoder of the satellite as claimed in claim 3, wherein the clear is implemented by the internal software of the photoelectric encoder when the precise code signal data is accumulated to 360 °, and the initial value of the incremental angle data is the absolute angle data collected when the photoelectric encoder is powered on and works.

5. The method of claim 1, wherein the intermediate fine code incremental data is a 4-times multiplied incremental binary count of two orthogonal code channels, a13A and a13B, of the last bit of the intermediate fine code.

6. The method for single-point reliability redundancy of a photoelectric encoder for a satellite of claim 5, wherein the initial value of the middle-fine code incremental data is the first 13 bit value of the absolute angle data collected when the photoelectric encoder is powered on.

Technical Field

The invention relates to the field of inertial actuating mechanisms of satellite attitude and orbit control systems, in particular to a single-point reliability redundancy technology of a photoelectric encoder for controlling a moment gyroscope.

Background

The control moment gyro is composed of a momentum wheel and a frame system, vector pointing control is carried out on angular momentum with constant magnitude through frame rotation, the angular momentum fast exchange is carried out with a satellite, the functions of maneuvering and stable control of the satellite attitude are realized, and the control moment gyro has the advantages of large output moment, small mass, low power consumption and the like.

The working principle of the control moment gyroscope is known, high-precision frame pointing control is the key for realizing high moment precision of the control moment gyroscope, and the reliability of the whole control moment gyroscope product is directly determined by the reliability of the frame high-precision position sensor technology.

The control moment gyro usually adopts an absolute type photoelectric encoder as a high-precision position sensor of a frame thereof. The control moment gyro product is constrained by space and weight, and the photoelectric tube and the signal path in the absolute photoelectric encoder used by the control moment gyro product are in a series mode, so that the reliability is low, and the risk of single-point failure exists (namely, the signal output of the whole absolute photoelectric encoder is abnormal due to the failure of any photoelectric tube and signal path in the absolute photoelectric encoder, so that the function failure of the control moment gyro product is caused).

Disclosure of Invention

The invention provides a single-point reliability redundancy method for a photoelectric encoder for a satellite, which enables an absolute type photoelectric encoder to have a function of switching an incremental mode in an absolute mode, realizes single-point reliability redundancy of the photoelectric encoder for the satellite and improves the reliability of products.

In order to achieve the above object, the present invention provides a single-point reliability redundancy method for a satellite photoelectric encoder, comprising the steps of: calculating absolute angle data, incremental angle data and precise code incremental data, and if the absolute angle data is equal to the incremental angle data, outputting the absolute angle data by the photoelectric encoder; if the absolute angle data is not equal to the incremental angle data due to the abnormal fine code channel, outputting the intermediate fine code incremental data by the photoelectric encoder; and if the absolute angle data is not equal to the incremental angle data due to the abnormity of the coarse code channel or the medium-fine code channel, the photoelectric encoder outputs the incremental angle data.

The absolute angle data is binary data obtained by superposing a coarse code, a medium fine code and a fine code after photoelectric conversion of the position angle after signal shaping processing.

The incremental angle data is obtained by incremental accumulation of the fine code signal data.

And when the precise code signal data are accumulated to 360 degrees, the precise code signal data are cleared by internal software of the photoelectric encoder, and the initial value of the incremental angle data is absolute angle data acquired when the photoelectric encoder is electrified and works.

The increment data of the middle fine code utilizes 4-frequency multiplication increment binary counting of two orthogonal code channels of A13A and A13B of the last bit in the middle fine code.

The initial value of the intermediate fine code incremental data is the first 13 bit value of the absolute angle data acquired when the photoelectric encoder is powered on.

The incremental angle data Dz and the middle precision code incremental data D13 obtained by operation are used as backup data of the absolute angle data Dj and are used for controlling closed-loop operation of the moment gyro, so that the absolute photoelectric encoder has the function of automatically switching the incremental mode in the absolute mode, single-point reliability redundancy of the photoelectric encoder for the satellite is realized, and the reliability of products is improved.

Drawings

Fig. 1 is a flowchart of a single-point reliability redundancy method for a satellite photoelectric encoder according to the present invention.

Fig. 2 is a schematic diagram of the frequency multiplication of the medium fine code 4.

Fig. 3 is a hardware architecture diagram of the present invention.

Detailed Description

The following description will specifically describe a preferred embodiment of the present invention with reference to fig. 1 to 3, using a 21-bit absolute type photoelectric encoder.

As shown in fig. 1, the present invention provides a single-point reliability redundancy method for a satellite photoelectric encoder, comprising the following steps:

step S1, absolute angle data Dj (21-bit binary data), incremental angle data Dz (21-bit binary data), and precise code incremental data D13 (13-bit binary data) are calculated.

In general, an absolute photoelectric encoder is used as an angle measuring component to realize photoelectric conversion of a position angle through a grating, and finally binary digital output is obtained.

The absolute angle data Dj (21-bit binary data) is obtained by directly superposing a coarse code (front 8 bits), a middle fine code (middle 5 bits) and a fine code (rear 8 bits) after photoelectric conversion of position and angle.

The increment angle data Dz (21-bit binary data) is obtained by increment accumulation of fine code signal data; and resetting by internal software of the photoelectric encoder when the data are accumulated to 360 degrees, wherein the initial value of the incremental angle data Dz is absolute angle data acquired when the photoelectric encoder is electrified and works.

As shown in fig. 2, the intermediate fine code incremental data D13 (13-bit binary data) uses 4-frequency multiplication incremental binary counts of two orthogonal code tracks (the code track depicts 2048 lines) of a13A and a13B of the last bit (i.e., the most precise bit in the intermediate fine code) in the intermediate fine code, and the initial value of the intermediate fine code incremental data D13 is the first 13-bit value of the absolute angle data acquired when the photoelectric encoder is powered on.

Step S2, determine whether the absolute angle data Dj is equal to the incremental angle data Dz, if yes, the photoelectric encoder outputs the absolute angle data Dj, otherwise, go to step S3.

And step S3, judging the reason for causing the absolute angle data Dj and the incremental angle data Dz to be unequal, if the absolute angle data Dj and the incremental angle data Dz are caused by the abnormality of the fine code channel, outputting medium fine code incremental data D13 by the photoelectric encoder, and if the absolute angle data Dj and the incremental angle data Dz are caused by the abnormality of the coarse code channel or the medium fine code channel, outputting the incremental angle data Dz by the photoelectric encoder.

Specifically, the data switching principle of the photoelectric encoder is as follows: after the photoelectric encoder is powered on and reset, outputting absolute angle data Dj by default; meanwhile, the photoelectric encoder compares whether the absolute angle data Dj is equal to the incremental angle data Dz or not in each operation period of internal software, outputs the absolute angle data Dj when Dj is equal to Dz, and switches the output data to the incremental angle data Dz when Dj is not equal to Dz; after the output data of the photoelectric encoder is switched to the increment angle data Dz, whether the increment angle data Dz or the medium-precision code increment data D13 should be output is further judged, if Dj ≠ Dz is caused by the abnormality of the precision code channel (i.e. the first 13 bit value of the increment angle data Dz ≠ medium-precision code increment data D13), the output data of the photoelectric encoder is switched from the increment angle data Dz to the medium-precision code increment data D13, and if Dj ≠ Dz is caused by the abnormality of the coarse code channel or the medium-precision code channel (i.e. the first 13 bit value of the increment angle data Dz is the medium-precision code increment data D13), the output data of the photoelectric encoder maintains the output increment angle data Dz.

As shown in fig. 3, in an embodiment of the present invention, the data calculating module calculates absolute angle data Dj, incremental angle data Dz, and middle precision code incremental data D13, the condition determining and data outputting module determines whether the photocell and its signal path inside the absolute photoelectric encoder are normal, and realizes correct switching between three sets of data calculated by the data calculating module according to the determination, so as to ensure normal operation of the photoelectric encoder. The data calculation module and the condition judgment and data output module are realized by an FPGA chip, the invention only needs to update on FPGA software, and a hardware circuit is not changed.

The incremental angle data Dz and the middle precision code incremental data D13 obtained by operation are used as backup data of absolute angle data Dj and are used for closed-loop operation of controlling the position or speed of a moment gyro frame, so that the absolute photoelectric encoder has the function of automatically switching an absolute mode into an incremental mode when any photoelectric tube in the absolute photoelectric encoder and a signal path of the photoelectric tube fail, single-point reliability redundancy of the photoelectric encoder for the satellite is realized, and the reliability of a product is improved.

While the present invention has been described in detail with reference to the preferred embodiments, it should be understood that the above description should not be taken as limiting the invention. Various modifications and alterations to this invention will become apparent to those skilled in the art upon reading the foregoing description. Accordingly, the scope of the invention should be determined from the following claims.