High-precision roll angle measuring system and method

Abstract

The invention discloses a high-precision roll angle measurement system and method, and relates to the technical field of precision measurement, and the system comprises a rotary table, a rotary receiver is rotatably connected with the rotary table, and the rotary receiver is used for detecting and outputting a roll angle sequence with a timestamp; the FPGA module is used for generating sampling pulses with fixed time intervals and triggering an encoder on the motor to output rotor position information through the sampling pulses; the positioning receiver is used for outputting accurate time information measured by each sampling pulse; and the upper computer software generates a reference rotor position sequence with a timestamp, accurately compares and analyzes the reference rotor position sequence and the roll angle sequence, and counts and calculates a roll angle measurement accuracy index of the rotary receiver. By adopting the scheme, the time and angle dual high precision of the reference roll angle is ensured, and a reliable reference is provided for accurately evaluating the roll angle performance of the tested rotary receiver.

Description

Technical Field

[0001] The present invention relates to the field of precision measurement technology, and in particular to a high-precision roll angle measurement system and method. Background Art

[0002] Rotating receivers are essential devices for measuring vehicle attitude (including roll angle) using signals from satellite navigation systems (such as Beidou and GPS). They are widely used in aviation, navigation, surveying, and mapping. Rotating receivers typically calculate the vehicle's roll angle by analyzing the periodic changes in received satellite signal strength, phase, or carrier Doppler frequency as the vehicle rotates. Accurate roll angle measurements are crucial for vehicle navigation, control, and mission completion.

[0003] To evaluate the roll angle measurement performance of rotating receivers, a measurement system that can provide a more accurate roll angle reference is required. Existing measurement methods may have the following shortcomings: First, the accuracy of the reference device is limited or the cost is too high, such as using a high-end inertial measurement unit (IMU). Second, the time synchronization accuracy is low, making it difficult to precisely align the reference angle with the measured angle, affecting the accurate assessment of dynamic measurement accuracy. Third, the system is complex to set up and inconvenient to operate, making it difficult to meet the requirements of fast, convenient, and low-cost testing.

[0004] Therefore, how to build a system and method that is simple in structure, cost-controlled, easy to implement, and can provide high-precision roll angle measurement is an urgent problem to be solved in the current technical field. Summary of the Invention

[0005] To address the deficiencies of the prior art, the present invention aims to provide a high-precision roll angle measurement system and method. This solution utilizes an FPGA to generate highly stable synchronous sampling pulses, combined with high-precision timing from a positioning receiver and precise position feedback from an encoder. This ensures high precision in both the time and angle of the reference roll angle, providing a reliable benchmark for accurately evaluating the roll angle performance of the rotating receiver under test.

[0006] The present invention is achieved through the following technical solutions: A high-precision roll angle measurement system, comprising: A turntable, on which is mounted a rotating receiver and a motor for driving the rotating receiver to rotate about its own axis, the rotating receiver being rotatably connected to the turntable, and the rotating receiver being used to measure and output a roll angle sequence with its own time stamp; An FPGA module is used to generate sampling pulses with fixed time intervals, and can trigger the encoder on the motor to output rotor position information through the sampling pulses; A positioning receiver, which is used to measure the precise time information of each sampling pulse; The host computer software is used to associate the precise time information with the corresponding rotor position information, generate a reference rotor position sequence with a timestamp, accurately compare and analyze the reference rotor position sequence and the roll angle sequence, and calculate the roll angle measurement accuracy index of the rotating receiver.

[0007] For further optimization, the output end of the motor and the end of the fixture on which the rotating receiver is mounted are both provided with gears, and the two gears mesh with each other for transmission.

[0008] For further optimization, the positioning receiver adopts a general satellite navigation receiver.

[0009] For further optimization, the host computer software also has a data storage module and a data display module. The data storage module is used to store the received information, and the data display module is used to provide data analysis tools and a graphical interface to display the information and analysis results.

[0010] Further optimized, the accuracy of the encoder is above 2500 lines / turn.

[0011] For further optimization, the FPGA module can generate a sampling pulse signal with a fixed period, and the period is adjustable, generally 1ms.

[0012] Further solutions: The present invention also provides a high-precision roll angle measurement method, comprising the following steps: S1: Set the test parameters and start the motor and FPGA module, so that the FPGA module generates sampling pulses at the set time interval; S2: The sampling pulse synchronously triggers the encoder on the motor to sample the rotor angular position and outputs the rotor position information to the host computer software; the positioning receiver synchronously receives the sampling pulse and outputs the precise time information of each sampling pulse measured by it to the host computer software; S3: The host computer software associates the precise time information with the corresponding rotor position information to generate a reference rotor position sequence with a timestamp; S4: The host computer software accurately compares and analyzes the reference rotor position sequence and the roll angle sequence output by the rotating receiver based on time synchronization, and calculates and calculates the roll angle measurement accuracy index of the rotating receiver.

[0013] For further optimization, step S3 further includes the following specific steps: The host computer software internally matches the sampling pulse sequence number or time by aligning the sampling pulse sequence number or time, and makes a strict one-to-one correspondence between the rotor position information obtained from the encoder and the precise time information obtained from the positioning receiver, thereby generating a reference rotor position sequence with a timestamp.

[0014] For further optimization, step S4 further includes the following specific steps: S41: The host computer software performs data preprocessing on the collected data; S42: Then, coarse synchronization is performed using the time information output by the rotating receiver itself and the precise UTC timestamp provided by the positioning receiver; S43: Then, using an interpolation algorithm, interpolate the reference rotor position sequence to the same time point as the roll angle output by the rotating receiver; S44: At the same precise time point, comparing the reference roll angle obtained by interpolation with the roll angle output by the rotation receiver, and calculating the roll angle error at each moment; S45: Finally, statistical analysis is performed on the error sequence within a period of time to calculate the roll angle measurement accuracy index of the rotating receiver.

[0015] For further optimization, after calculating the roll angle measurement accuracy of the rotating receiver, the host computer software stores all data through the data storage module, and provides a graphical user interface through the data display module to display the received data and various statistical accuracy indicators in real time or playback.

[0016] Compared with the prior art, the present invention has the following advantages and beneficial effects: 1. This invention provides a high-precision roll angle measurement system and method. This system uses an FPGA to generate highly stable synchronous sampling pulses, combined with a positioning receiver for high-precision timing of these pulses and precise rotor position feedback from a high-resolution motor encoder (over 2500 lines / turn). This ensures high-precision both the time and angle of the reference roll angle, providing a reliable benchmark for accurately evaluating the roll angle performance of the rotating receiver under test. 2. This invention provides a high-precision roll angle measurement system and method. The system primarily consists of a general-purpose FPGA module, a positioning receiver with external event input, a standard motor turntable, and a host computer. This eliminates the need for expensive high-precision inertial devices as a reference, significantly reducing the cost of building the test system. 3. This invention provides a high-precision roll angle measurement system and method. The host computer software integrates multiple functions, including data acquisition, time synchronization, comparative analysis, turntable control, data storage, and display, achieving automation and intelligent testing, and simple and fast operation. The host computer software also includes built-in algorithms for data interpolation and error statistics, and provides data storage and visualization analysis capabilities, facilitating in-depth analysis and traceability of test results. 4. The present invention provides a high-precision roll angle measurement system and method with adjustable FPGA sampling pulse interval and controllable turntable speed, which can adapt to the testing requirements of different types of rotating receivers and can be expanded with other sensors or analysis modules as needed. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the examples. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can also derive other relevant drawings based on these drawings without inventive effort. In the drawings: Figure 1 A schematic structural diagram of the high-precision roll angle measurement system provided by the present invention; Figure 2 A schematic diagram of the process flow of the high-precision roll angle measurement method provided by the present invention; Figure 3 This is a test result diagram in Example 3 provided by the present invention.

[0018] Markings and corresponding parts names in the accompanying drawings: 10-turntable, 11-encoder, 20-FPGA module, 30-positioning receiver, 40-host computer software, 50-rotation receiver. DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with examples and drawings. The exemplary embodiments of the present invention and their descriptions are only used to explain the present invention and are not intended to limit the present invention.

[0020] Embodiment 1: This embodiment 1 provides a high-precision roll angle measurement system, including: A motor-driven turntable supports the rotating receiver under test and can precisely rotate at a preset angular velocity or position. The turntable's motor is equipped with a high-resolution encoder with an accuracy of at least 2500 lines per revolution, which accurately outputs the turntable's rotor angular position in real time.

[0021] FPGA (Field Programmable Gate Array) module: Used to generate sampling pulses with a configurable fixed interval. The interval is typically, but not limited to, 1 millisecond. The sampling pulses serve as a reference signal for synchronizing multiple devices within the system.

[0022] Positioning Receiver: This receiver can be a general-purpose satellite navigation receiver. Equipped with an external event input interface and precise timing, it receives the sampling pulses generated by the FPGA module and performs high-precision time measurement of the precise arrival moment of each sampling pulse, with a time measurement accuracy better than 50 nanoseconds. The positioning receiver may also need to receive rotor position information from the turntable motor servo system or processed by the FPGA module, though this depends primarily on the specific system integration solution. Its core function is to provide accurate timestamps.

[0023] Host computer software: It is installed and run in the computer, connected to the motor-driven turntable, FPGA module (or the encoder data interface controlled by it) and positioning receiver through the communication interface, and is used to: (a) receiving rotor position information output by a motor encoder triggered by a sampling pulse generated by the FPGA module; (b) receiving precise time information measured by the positioning receiver for each sampling pulse; (c) associating the precise time information with the corresponding rotor position information to generate a reference rotor position sequence with a high-precision time stamp, which serves as a precise reference roll angle of the turntable; (d) receiving data output from a rotating receiver containing information such as position, velocity, time and roll angle; (e) using data processing methods such as interpolation algorithms, based on time synchronization, to accurately compare and analyze the reference rotor position sequence (i.e., reference roll angle) with the high-precision timestamp and the roll angle sequence output by the rotating receiver, and to statistically calculate the roll angle measurement accuracy of the rotating receiver; (f) controlling the speed, direction, start and stop of the turntable driven by the motor; (g) Storing and managing the collected reference rotor position data, precise time information, rotating receiver data, and accuracy analysis results; (h) Graphically display and analyze the collected data and analysis results.

[0024] Example 2: This example 2 is further optimized based on example 1. Figure 2 As shown, a high-precision roll angle measurement method is provided, comprising the following steps: Step 1: System Initialization and Synchronization Pulse Generation: Start the motor-driven turntable, FPGA module, positioning receiver, and host computer software. The FPGA module generates sampling pulses with a configurable fixed interval (typically 1 millisecond).

[0025] Step 2: Obtain reference roll angle data and accurate timestamp: (a) The sampling pulse synchronously triggers the turntable motor encoder to sample the rotor angular position; (b) The host computer software receives and records the rotor position information output by the motor encoder; (c) The sampling pulses are synchronously input to a positioning receiver, which accurately measures the arrival time of each sampling pulse (with an accuracy better than or equal to 50 nanoseconds) and reports the measured precise time information to the host computer software; (d) The host computer software associates the received precise time information with the corresponding rotor position information to generate a reference rotor position sequence with a high-precision timestamp as a high-precision reference roll angle.

[0026] Step 3: Data acquisition of the rotating receiver under test: The host computer software synchronously receives the roll angle and other data with time stamps output in real time by the rotating receiver under test.

[0027] Step 4: Roll Angle Comparison and Accuracy Assessment: Based on the timestamp information, the host computer software uses algorithms such as interpolation to precisely align the reference roll angle sequence with a high-precision timestamp on the time axis with the roll angle sequence output by the rotating receiver. The software then compares the two point by point, calculating the difference between the two and using statistical analysis to obtain the rotating receiver's roll angle measurement accuracy indicators (such as standard deviation).

[0028] Step 5: Turntable control: The host computer software controls the motor speed, direction, start and stop according to the test requirements.

[0029] Step 6: Data storage, analysis, and display: The host computer software stores all collected raw data, timestamp information, processed reference roll angle sequence, rotation receiver data, and final accuracy assessment results, and provides data analysis tools and a graphical interface to display various information and analysis results.

[0030] Example 3: This example 3 is based on Example 2 and combines Figure 1-Figure 3 , provides a specific implementation method.

[0031] Reference Figure 1A high-precision roll angle measurement system provided in Example 3 of the present invention primarily includes a motor-driven turntable 10, an FPGA module 20, a positioning receiver 30, and host computer software 40. Positioning receiver 30 utilizes a general-purpose satellite navigation receiver. A rotation receiver 50 to be measured is mounted on the motor-driven turntable 10.

[0032] The motor-driven turntable 10 carries the rotating receiver 50 and rotates precisely at the speed set by the host computer software 40. The turntable 10's motor is equipped with a high-resolution encoder 11, with a resolution of at least 2500 lines per revolution, which outputs the precise rotor angular position of the turntable 10 in real time. This rotor angular position information can be used directly or after simple conversion as the instantaneous reference roll angle.

[0033] The FPGA module 20 generates highly stable periodic sampling pulses. The pulse interval T can be set by the host computer software 40; a typical interval is 1 millisecond. These sampling pulses trigger the turntable encoder 11 (or its data acquisition interface) to lock and output the current rotor position data upon pulse arrival. Furthermore, these sampling pulses are input as external event signals to the positioning receiver 30.

[0034] The positioning receiver 30 is a satellite navigation receiver with external event input and high-precision timing capabilities. When its external event input port receives a sampling pulse sent by the FPGA module 20, the positioning receiver 30 uses its internal satellite timing function to mark the arrival time of the pulse with a high-precision UTC timestamp, with a time accuracy of 50 nanoseconds or better. The positioning receiver 30 sends this information (sampling pulse sequence number, precise timestamp) to the host computer software 40 via a data interface (such as an RS232 serial port or Ethernet port). At the same time, the positioning receiver 30 may also need to receive rotor position information processed by the turntable motor servo system or FPGA module, but this mainly depends on the specific system integration solution. The core function is to provide a precise timestamp. In this preferred embodiment, the rotor position information is directly obtained by the host computer software from the encoder interface or FPGA.

[0035] The host computer software 40 is the control and data processing core of this system and runs on a PC or industrial computer. Its main functional modules and workflow are as follows: System control module: Send instructions to the motor-driven turntable 10 to control its start, stop, rotation direction and rotation speed; Configuration instructions can be sent to the FPGA module 20 to set parameters such as the interval of the sampling pulse.

[0036] Data acquisition and time synchronization module: The rotor position data output by the motor encoder 11 triggered by the FPGA sampling pulse is collected in real time through a corresponding interface (such as a high-speed data acquisition card, a serial port or a network interface); Receive accurate time stamp information corresponding to each sampling pulse reported by the positioning receiver 30 in real time through the communication interface; Receive in real time through the communication interface the roll angle reading including the time stamp, the raw satellite observation value (if analysis is required), and possible self-positioning and timing information output by the rotation receiver 50 to be tested; The host computer software 40 internally matches the rotor position data obtained from the encoder with the precise timestamp data obtained from the positioning receiver 30 by aligning the sampling pulse sequence number or time, thereby forming a high-precision (time, reference roll angle) sequence.

[0037] Data processing and accuracy assessment module: Data preprocessing: Perform necessary format conversion, filtering (if necessary), and other processing on the collected data.

[0038] Time alignment and interpolation: Since the time reference of the roll angle output by the rotating receiver 50 may be different from the UTC time reference provided by the positioning receiver 30, the upper computer software 40 uses the time information output by the rotating receiver 50 itself and the precise timestamp provided by the positioning receiver 30 to first perform coarse synchronization, and then uses a high-precision interpolation algorithm (such as linear interpolation, polynomial interpolation or spline interpolation) to interpolate the high-precision (time, reference roll angle) sequence to the same time point as the roll angle output by the rotating receiver 50.

[0039] Error calculation and statistics: At the same precise time point, the interpolated reference roll angle is compared with the roll angle output by the rotating receiver 50 to calculate the roll angle error at each moment. Statistical analysis is then performed on the error sequence over a period of time to calculate accuracy metrics such as mean error, standard deviation, root mean square error (RMS), and maximum error.

[0040] Data storage and display module: All raw data (encoder data, BeiDou timestamps, rotating receiver data), processed intermediate data (such as aligned sequences), and final accuracy assessment results are stored in a hard disk file in a certain format for easy reference and analysis. A graphical user interface (GUI) is provided to display the reference roll angle curve of the turntable, the roll angle curve output by the rotating receiver 50, the error curve between the two, and various statistical accuracy indicators in real time or in playback.

[0041] Example of method implementation process (refer to Figure 2 ): S201: System preparation and initialization: The operator sets the test parameters, such as the rotation speed of the turntable, sampling pulse interval, etc., through the host computer software 40 and starts each device.

[0042] S202: FPGA generates synchronous sampling pulses: FPGA module 20 starts to generate sampling pulses at a set interval (such as 1ms).

[0043] S203: Reference Data Acquisition and Time Calibration: Each sampling pulse triggers encoder 11 to output the rotor position, which is recorded by host computer software 40. Simultaneously, the pulse is sent to positioning receiver 30, which adds a high-precision UTC timestamp to it and uploads it to host computer software 40. Host computer software 40 associates the rotor position with the precise timestamp to form a reference roll angle sequence.

[0044] S204: Measured Data Acquisition: The host computer software 40 synchronously collects the roll angle data and its time information output by the rotation receiver 50. The host computer software 40 internally aligns the sampling pulse numbers or times to match the rotor position data obtained from the encoder with the precise timestamp data obtained from the positioning receiver 30, forming a highly accurate (time, reference roll angle) sequence.

[0045] S205: Data processing and accuracy analysis: Data pre-processing: The host computer software 40 performs necessary format conversion, filtering (if necessary), and other processing on the collected data; Time alignment and interpolation: Because the time reference of the roll angle output by the rotating receiver 50 may differ from the UTC time reference provided by the positioning receiver 30, and the sampling times may not be completely consistent, the host computer software 40 uses the time information output by the rotating receiver 50 itself and the precise UTC timestamp provided by the positioning receiver 30 to first perform coarse synchronization. Then, using a high-precision interpolation algorithm (such as linear interpolation, polynomial interpolation, or spline interpolation), the high-precision (time, reference roll angle) sequence is interpolated to the same time point as the roll angle output by the rotating receiver 50, or vice versa. Error calculation and statistics: At the same precise time point, the interpolated reference roll angle is compared with the roll angle output by the rotating receiver 50 to calculate the roll angle error at each moment. Statistical analysis is then performed on the error sequence over a period of time to calculate accuracy metrics such as mean error, standard deviation, root mean square error (RMS), and maximum error.

[0046] S206: Turntable control: During the test process or during the test interval, the host computer software 40 can adjust the motion state of the turntable 10 as needed.

[0047] S207: Result display and storage: The host computer software 40 displays the test curve and results in real time (reference Figure 3 ) and save all relevant data after the test.

[0048] The system and method described above utilizes an FPGA to generate a unified, highly stable sampling pulse as a time reference. The positioning receiver then assigns a highly precise time meaning to this reference, resulting in a turntable-provided reference roll angle with extremely high temporal and angular accuracy. The host computer software, through sophisticated synchronization and data processing algorithms, accurately assesses the roll angle accuracy of the rotating receiver under test, providing an effective technical means for performance testing and calibration of rotating receivers.

[0049] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-precision roll angle measurement system, characterized in that: include: A turntable (10), wherein a rotation receiver (50) and a motor for driving the rotation receiver (50) to rotate around its own axis are mounted on the turntable (10), the rotation receiver (50) and the turntable (10) are rotationally connected, and the rotation receiver (50) is used to measure and output a roll angle sequence with a time stamp; An FPGA module (20) is used to generate sampling pulses with a fixed time interval, and can trigger the encoder (11) on the motor to output rotor position information through the sampling pulses; A positioning receiver (30) for measuring precise time information of each sampling pulse; The host computer software (40) is used to associate the precise time information with the corresponding rotor position information, generate a reference rotor position sequence with a time stamp, accurately compare and analyze the reference rotor position sequence and the roll angle sequence, and calculate and calculate the roll angle measurement accuracy index of the rotating receiver (50).

2. A high-precision roll angle measurement system according to claim 1, characterized in that: The output end of the motor and the end of the fixture connected to the rotating receiver (50) are both provided with gears, and the two gears mesh with each other for transmission.

3. The high-precision roll angle measurement system according to claim 1, characterized in that: The positioning receiver (30) adopts a general satellite navigation receiver.

4. The high-precision roll angle measurement system according to claim 1, characterized in that: The host computer software (40) also has a data storage module and a data display module. The data storage module is used to store various received information, and the data display module is used to provide a data analysis tool and a graphical interface to display various information and analysis results.

5. The high-precision roll angle measurement system according to claim 1, characterized in that: The encoder (11) has an accuracy of more than 2500 lines / turn.

6. The high-precision roll angle measurement system according to claim 1, characterized in that: The FPGA module (20) can generate a sampling pulse signal with a fixed period.

7. The measurement method of a high-precision roll angle measurement system according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1: setting test parameters, and starting the motor and the FPGA module (20), so that the FPGA module (20) generates sampling pulses according to the set time interval; S2: The encoder on the motor is synchronously triggered by the sampling pulse to sample the rotor angular position, and the rotor position information is output to the host computer software (40); the positioning receiver (30) synchronously receives the sampling pulse and outputs the precise time information of each sampling pulse to the host computer software (40); S3: The host computer software (40) associates the precise time information with the corresponding rotor position information to generate a reference rotor position sequence with a timestamp; S4: The host computer software (40) accurately compares and analyzes the reference rotor position sequence and the roll angle sequence output by the rotating receiver (50) based on time synchronization, and statistically calculates the roll angle measurement accuracy index of the rotating receiver (50).

8. The measurement method of a high-precision roll angle measurement system according to claim 7, characterized in that: The step S3 further includes the following specific steps: The host computer software (40) internally matches the sampling pulse sequence number or time, and makes a strict one-to-one correspondence between the rotor position information obtained from the encoder (11) and the precise time information obtained from the positioning receiver (30), thereby generating a reference rotor position sequence with a timestamp.

9. The measurement method of a high-precision roll angle measurement system according to claim 7, characterized in that: The step S4 further comprises the following specific steps: S41: the host computer software (40) performs data preprocessing on the collected data; S42: Then, coarse synchronization is performed using the time information output by the rotation receiver (50) itself and the precise UTC timestamp provided by the positioning receiver (30); S43: Then, by using an interpolation algorithm, the reference rotor position sequence is interpolated to the same time point as the roll angle output by the rotating receiver (50); S44: at the same precise time point, comparing the reference roll angle obtained by interpolation with the roll angle output by the rotation receiver (50), and calculating the roll angle error at each moment; S45: Finally, statistical analysis is performed on the error sequence within a period of time to calculate the roll angle measurement accuracy index of the rotation receiver (50).

10. The measurement method of a high-precision roll angle measurement system according to claim 7, characterized in that: After calculating the roll angle measurement accuracy of the rotating receiver (50), the host computer software (40) stores all data through the data storage module and provides a graphical user interface through the data display module to display the received data and various statistical accuracy indicators in real time or in playback.

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