An inertial system frame component static balance detection system and detection method

Abstract

The application relates to a static balance detection system of an inertial system frame component, which comprises a detection table and a control unit, the detection table comprises a left support, a right support, a torque motor, a horizontal driving shaft, a circular grating, a horizontal supporting shaft and a grating reading head, the left support and the right support are oppositely arranged, the left support is provided with the torque motor, the rotor of the torque motor drives the horizontal driving shaft, the right support is provided with the circular grating, the inner ring of the circular grating is coaxially provided with the horizontal supporting shaft, the horizontal driving shaft and the horizontal supporting shaft are coaxially arranged and horizontally provided with the frame component to be detected, and the right support is provided with the grating reading head; the control unit comprises a motion control module, a data acquisition module, an upper computer and a man-machine interface, the motion control module acquires a real-time torque detection value of the torque motor, and the grating reading head acquires a real-time angle signal. The application carries out data analysis on the collected real-time torque to obtain a mass center eccentric torque, calculates a mass center shift position, realizes automatic static balance detection, and improves the detection efficiency.

Description

Technical Field

[0001] This invention belongs to the field of inertial navigation technology, and in particular to a static balance detection system and method for inertial system frame components. Background Technology

[0002] In high-precision inertial navigation systems, a shaft rotation structure is employed, utilizing multi-axis rotation for modulation and demodulation to eliminate system errors. The smoothness and jitter of the shaft rotation can affect system accuracy. This necessitates that the center of mass of each rotation axis lie on the rotation axis to avoid impacts on the drive motor and to ensure smooth system rotation. This requires static balancing of each frame component after assembly. After detecting the eccentricity, balancing is performed to ensure the center of mass coincides with the rotation axis. Currently, a common static balancing method involves attaching process shafts to both ends of the frame component, placing it on a pair of tool holders, manually rotating the frame component back and forth, installing counterweights, adjusting their size and position until the frame component can remain naturally stationary at any angle, weighing the counterweights, measuring their installation position, calculating the center of mass, and then applying the final counterweight to achieve static balance. This method is simple and does not require sophisticated balancing structures, but it is inefficient. In mass production, static balancing becomes a bottleneck in assembly.

[0003] Therefore, it is necessary to improve the static balance detection system and detection method for inertial navigation products in order to improve processing and assembly efficiency. Summary of the Invention

[0004] The purpose of this invention is to overcome the low efficiency of static balance testing of inertial system frame components, and to provide a static balance testing system and method for inertial system frame components. Based on the structural characteristics of the frame components themselves, a control system is constructed using a motor, a circular grating, and the rotational shaft system of the frame components. The motor outputs torque to drive the frame components to rotate at a uniform speed, while the magnitude of the output torque is measured. The collected torque data is analyzed to obtain the centroid eccentricity torque, and the centroid offset position is calculated, thereby realizing automated static balance testing of the frame components and improving testing efficiency.

[0005] The technical problem solved by this invention is achieved through the following technical solution:

[0006] A static balance testing system for an inertial system frame component is characterized by comprising a testing platform and a control unit. The testing platform includes a left support, a right support, a torque motor, a horizontal drive shaft, a circular grating, a horizontal support shaft, and a grating reading head. The left and right supports are arranged opposite to each other. The torque motor is mounted on the left support, and its rotor drives the horizontal drive shaft. The circular grating is mounted on the right support, and the horizontal support shaft is coaxially mounted on the inner ring of the grating. The frame component under test is horizontally mounted on the horizontal drive shaft and the horizontal support shaft. The grating reading head is mounted on the right support. The control unit includes a motion control module, a data acquisition module, a host computer, and a human-machine interface. The motion control module is connected to the torque motor to control and acquire its motion parameters. The motion control module is connected to the grating reading head to the data acquisition module. The motion control module acquires the real-time torque detection value of the torque motor, and the grating reading head acquires the real-time angle signal. The motion control module and the data acquisition module are communicatively connected to the host computer, which has a human-machine interface.

[0007] Furthermore, a first air bearing is installed between the horizontal drive shaft and the torque motor housing, and a second air bearing is installed between the horizontal support shaft and the circular grating.

[0008] Furthermore, both the horizontal drive shaft and the horizontal support shaft are provided with symmetrical bolt connection holes, which are fixedly connected to the symmetrical connecting shafts on both sides of the frame component by bolts.

[0009] A method for static balance detection of an inertial system frame component, characterized by comprising the following steps:

[0010] 1) The inertial navigation system frame component is installed on the test bench: the connecting shafts on both sides of the inertial navigation system frame component are connected to the horizontal drive shaft and the horizontal support shaft respectively. The rotation shafts of the inertial navigation system frame component, the torque motor, and the circular grating are horizontal and coaxial.

[0011] 2) Detection system loop setup: The torque motor, frame component, circular grating, motion control module, data acquisition module and host computer constitute the detection system loop. The motion control module receives instructions from the host computer to control the torque motor and drive the frame component to rotate according to predetermined parameters.

[0012] 3) Determine the zero point position of the detection system: Mark the zero point position on the frame, and align the mark with the fixed position calibrated by the circular grating at the initial position of the frame;

[0013] 4) Rotation of inertial navigation system frame components: The motion control module controls the torque motor to drive the inertial navigation system frame components to rotate according to specified parameters, including forward rotation, reverse rotation, and at least two rotation speeds;

[0014] 5) Collect the output torque and angle output values ​​of the torque motor during rotation: When the control circuit is operating normally and the frame components are rotating uniformly, the real-time torque of the torque motor and the real-time angle output value of the circular grating are collected simultaneously. The torque motor data and the circular grating data at the same moment correspond one-to-one.

[0015] 6) Torque data analysis: Filter the raw real-time torque data, select the data after the rotational speed stabilizes, and fit the real-time torque with a sine and cosine function to form a torque sine and cosine function that is only affected by gravity.

[0016] 7) Calculation of the center of mass position: The maximum torque M and its corresponding circular grating output angle α are obtained. Based on the mass m of the frame component, the length L of the eccentric lever arm of the center of mass is calculated using the formula M = mgL. At the same time, the position of the center of mass of the frame component is obtained through the output angle of the circular grating.

[0017] Furthermore, in step 4), the torque electric rotation speed is 10r / min-120r / min. In step 6), the maximum torque generated by forward and reverse rotation is weighted and averaged to eliminate system error. The difference in the maximum output torque at different speeds is compared. When the maximum torque deviation at different speeds is within 1%, the maximum torque at the lowest speed is taken. If the error is greater than 1%, the system is adjusted to reduce friction.

[0018] The advantages and beneficial effects of this invention are as follows:

[0019] 1. The static balance detection system for the inertial system frame component of the present invention uses a torque motor, a circular grating angle sensor and the rotation axis system of the frame component to form a detection system. The torque motor outputs torque to drive the frame component to rotate at a uniform speed. At the same time, the magnitude of the output torque is measured, and the data of the collected real-time torque is analyzed to obtain the centroid eccentricity torque. The centroid offset position is calculated, realizing automated static balance detection and improving detection efficiency.

[0020] 2. The static balance detection system for the inertial system frame components of the present invention uses a motor with low friction torque, such as a brushless torque motor, due to the need for system balance accuracy. The motor has excellent performance and good linearity between output current and torque to ensure accurate torque measurement. The angle sensor is also selected in a frictionless manner, using a circular grating sensor, which transmits angle signals through photoelectric signals without contact or friction, thus ensuring detection accuracy.

[0021] 3. In the static balance detection system of the inertial system frame component of the present invention, a first air bearing is installed between the horizontal drive shaft and the torque motor housing, and a second air bearing is installed between the horizontal support shaft and the circular grating, so as to minimize the impact of friction on the detection system.

[0022] 4. The static balance detection system for the inertial system frame component of the present invention has a horizontal drive shaft, a horizontal support shaft and a symmetrical connecting shaft on both sides of the frame component, which makes installation more convenient and improves detection efficiency.

[0023] 5. The static balance detection method for the inertial system frame component of the present invention involves a motion control module controlling a torque motor to drive the inertial navigation system frame component to rotate according to specified parameters. The rotation parameters include forward rotation, reverse rotation, and at least two rotation speeds. The maximum torque generated by forward and reverse rotation is weighted and averaged to eliminate system errors. The difference in the maximum output torque at different speeds is compared. When the deviation of the maximum torque at different speeds is within 1%, the maximum torque at the lowest speed is taken to avoid the influence of system errors and improve detection accuracy.

[0024] 6. The static balance detection method for the inertial system frame components of the present invention uses a torque electric rotation speed of 10 r / min-120 r / min. The rotation speed should not be too low or too high. Too low a speed will cause creep, and too high a speed is not conducive to sampling of the motor output torque. The rotation stability should be high. After the torque sampling, filtering and data processing should be performed to obtain the maximum torque value to ensure accuracy. Depending on the actual situation, it is usually necessary to perform forward rotation, reverse rotation, speed change and other attitude control and sampling to reduce friction and system rotation accuracy error, analyze and obtain the maximum output torque value, and ensure the accuracy of the maximum torque.

[0025] 7. The static balance detection system and method for inertial system frame components of the present invention overcomes the shortcomings of low efficiency of the original method, greatly improves the detection efficiency, and has reference value for the static balance and center of mass eccentricity detection of rotating components of other non-inertial navigation systems. Attached Figure Description

[0026] Figure 1 This is a schematic block diagram of the static balance detection system for the inertial system frame components of the present invention.

[0027] Figure 2 This is a schematic diagram of the testing platform of the static balance testing system for the inertial system frame components of the present invention;

[0028] Figure 3 for Figure 2 A longitudinal sectional view;

[0029] Figure 4 for Figure 2 A transverse sectional view;

[0030] Figure 5 This is a torque data analysis diagram of the present invention.

[0031] Explanation of reference numerals in the attached figures

[0032] 1-Left support, 2-Frame component, 3-Right support, 4-Circular grating, 5-Grate reading head, 6-Base, 7-Torque motor, 8-Rotor, 9-Horizontal drive shaft, 10-Stator, 11-Torque motor housing, 12-First air bearing, 13-Connecting shaft, 14-Horizontal support shaft, 15-Second air bearing. Detailed Implementation

[0033] The present invention will be further described in detail below through specific embodiments. The following embodiments are merely descriptive and not limiting, and should not be used to limit the scope of protection of the present invention.

[0034] A static balance testing system for an inertial system frame component includes a testing platform and a control unit. Figure 1-4 As shown, the testing platform includes a left support 1, a right support 3, a torque motor 7, a horizontal drive shaft 9, a circular grating 4, a horizontal support shaft 14, and a grating reading head 5. The left and right supports are fixed to the base 6. The torque motor is mounted on the left support, and the torque motor includes a stator 10 and a rotor 8. The torque motor rotor 8 drives the horizontal drive shaft. The circular grating is mounted on the right support, and the horizontal support shaft is coaxially mounted on the inner ring of the circular grating. The test frame component 2 is horizontally mounted coaxially with the horizontal drive shaft and the horizontal support shaft. The grating reading head is mounted on the right support.

[0035] The control unit includes a motion control module, a data acquisition module, a host computer, and a human-machine interface. The motion control module is connected to the torque motor to control and acquire the motion parameters of the torque motor. The motion control module is connected to the data acquisition module via a grating reading head. The motion control module acquires the real-time torque detection value of the torque motor, and the grating reading head acquires the real-time angle signal. The motion control module and the data acquisition module are communicatively connected to the host computer, which is equipped with a human-machine interface.

[0036] A first air bearing 12 is installed between the horizontal drive shaft and the torque motor housing 11, and a second air bearing 15 is installed between the horizontal support shaft and the circular grating.

[0037] Both the horizontal drive shaft and the horizontal support shaft are provided with symmetrical bolt connection holes, and are fixedly connected to the symmetrical connecting shafts 13 on both sides of the frame component by bolts.

[0038] A method for static balance detection of an inertial system frame component, comprising the following steps:

[0039] 1) The inertial navigation system frame component is installed on the test bench: the connecting shafts on both sides of the inertial navigation system frame component are connected to the horizontal drive shaft and the horizontal support shaft respectively. The rotation shafts of the inertial navigation system frame component, the torque motor, and the circular grating are horizontal and coaxial.

[0040] 2) Detection system loop setup: The torque motor, frame component, circular grating, motion control module, data acquisition module and host computer constitute the detection system loop. The motion control module receives instructions from the host computer to control the torque motor and drive the frame component to rotate according to predetermined parameters.

[0041] 3) Determine the zero point position of the detection system: Mark the zero point position on the frame, and align the mark with the fixed position calibrated by the circular grating at the initial position of the frame;

[0042] 4) Rotation of inertial navigation system frame components: The motion control module controls the torque motor to drive the inertial navigation system frame components to rotate according to specified parameters, including forward rotation, reverse rotation, and at least two rotation speeds;

[0043] The torque electric rotation speed is 10 r / min-120 r / min.

[0044] 5) Collect the output torque and angle output values ​​of the torque motor during rotation: When the control circuit is operating normally and the frame components are rotating uniformly, the real-time torque of the torque motor and the real-time angle output value of the circular grating are collected simultaneously. The torque motor data and the circular grating data at the same moment correspond one-to-one.

[0045] 6) Torque data analysis: Filter the raw real-time torque data, select the data after the rotational speed stabilizes, and fit the real-time torque with a sine and cosine function to form a torque sine and cosine function that is only affected by gravity.

[0046] First, the raw data is filtered to form a relatively smooth curve. The initial stage should not be included in the data analysis because the data in the initial stage cannot be used to calculate the unbalanced torque due to static friction torque, moment of inertia, etc. Data after the rotational speed has stabilized should be selected, and the data should be fitted with a sine and cosine function, because theoretically the disturbance torque generated by gravity should be a sine and cosine function when rotating.

[0047] The maximum torque generated by forward and reverse rotation is weighted and averaged to eliminate system error. The difference in maximum output torque at different speeds is compared. When the deviation of the maximum torque at different speeds is within 1%, the maximum torque at the lowest speed is taken. If the error is greater than 1%, the system is adjusted to reduce friction.

[0048] 7) Calculation of the center of mass position: The maximum torque M and its corresponding circular grating output angle α are obtained. Based on the mass m of the frame component, the length L of the eccentric lever arm of the center of mass is calculated using the formula M = mgL. At the same time, the position of the center of mass of the frame component is obtained through the output angle of the circular grating.

[0049] For example, a 5kg frame component is placed in the detection system, with its left end connected to a torque motor and its right end connected to a circular grating. The rotation circuit is started at 10r / min and 60r / min for both forward and reverse rotation. Data from the torque motor and the circular grating reading head are collected by the data acquisition module. After 5Hz filtering and forward rotation fitting, the difference between the four maximum torque values ​​at the two speeds and in both forward and reverse rotation is found to be within 1%. Figure 5 As shown: the value is 0.5 Nm, the centroid offset position is in the direction at 100° with the starting position, and the radius from the rotation axis is 0.5 / (5*9.8)=0.0102m.

[0050] This invention is used to detect the static balance of the frame components of an inertial system. Simply put the frame component into the test table and rotate it a few times. The magnitude and position of the center of mass offset can be obtained through the torque motor and the circular grating sensor. The eccentricity detection of a frame component usually only takes 20-30 seconds, which greatly improves the detection efficiency and accuracy.

[0051] Although the embodiments and drawings of the present invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations and modifications are possible without departing from the spirit and scope of the invention and the appended claims. Therefore, the scope of the invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A method for static balance detection of inertial system frame components, characterized in that: Based on the static balance testing system, the static balance testing system includes a testing platform and a control unit. The testing platform includes a left support (1), a right support (3), a torque motor (7), a horizontal drive shaft (9), a circular grating (4), a horizontal support shaft (14), and a grating reading head (5). The left support (1) and the right support (3) are arranged opposite to each other. The torque motor (7) is installed on the left support (1), and the rotor (8) of the torque motor (7) drives the horizontal drive shaft (9). The circular grating (4) is installed on the right support (3), and the horizontal support shaft (14) is coaxially installed on the inner ring of the circular grating (4). The horizontal drive shaft (9) and the horizontal support shaft (14) are coaxially connected. The frame component to be tested (2) is installed horizontally on the shaft, and the grating reading head (5) is installed on the right support (3); the control unit includes a motion control module, a data acquisition module, a host computer and a human-machine interface. The motion control module is connected to the torque motor (7) to control and acquire the motion parameters of the torque motor (7). The motion control module is connected to the grating reading head (5) to the data acquisition module. The motion control module acquires the real-time torque detection value of the torque motor (7), and the grating reading head (5) acquires the real-time angle signal. The motion control module, the data acquisition module and the host computer are connected in communication. The host computer is equipped with a human-machine interface. The static balance detection method for the inertial system frame components includes the following steps: 1) The inertial navigation system frame component is installed on the test bench: the two sides of the frame component (2) of the inertial navigation system are connected to the horizontal drive shaft (9) and the horizontal support shaft (14) respectively. The frame component (2) of the inertial navigation system, the torque motor (7), and the circular grating (4) are horizontal and coaxially arranged. 2) Detection system loop setting: The torque motor (7), frame component (2), circular grating (4), motion control module, data acquisition module and host computer form a detection system loop. The motion control module receives instructions from the host computer to control the torque motor (7) and drive the frame component (2) to rotate according to predetermined parameters. 3) Determine the zero point position of the detection system: make zero point position markings on the frame component (2), and align the markings at the initial position of the frame with the fixed position calibrated by the circular grating (4); 4) Rotation of the inertial navigation system frame component: The motion control module controls the torque motor (7) to drive the inertial navigation system frame component (2) to rotate according to specified parameters, including forward rotation, reverse rotation and at least two rotation speeds; 5) Collect the output torque and angle output values ​​of the torque motor during rotation: When the control circuit is operating normally and the frame component (2) rotates uniformly, the real-time torque of the torque motor (7) and the real-time angle output value of the circular grating (4) are collected at the same time. The data of the torque motor (7) and the data of the circular grating (4) at the same time correspond one-to-one. 6) Torque data analysis: Filter the raw real-time torque data, select the data after the rotational speed stabilizes, and fit the real-time torque with a sine and cosine function to form a torque sine and cosine function that is only affected by gravity. 7) Calculation of the center of mass position: The maximum torque M and its corresponding output angle α of the circular grating (4) are obtained. Based on the mass m of the frame component (2), the length L of the eccentric lever arm of the center of mass is calculated by the formula M = mgL. At the same time, the position of the center of mass of the frame component (2) is obtained by the output angle of the circular grating (4).

2. The static balance detection method for inertial system frame components according to claim 1, characterized in that: A first air bearing (12) is installed between the horizontal drive shaft (9) and the housing of the torque motor (7), and a second air bearing (15) is installed between the horizontal support shaft (14) and the circular grating (4).

3. The static balance detection method for inertial system frame components according to claim 1, characterized in that: The horizontal drive shaft (9) and the horizontal support shaft (14) are both provided with symmetrical bolt connection holes, and are fixedly connected to the symmetrical connecting shafts (13) on both sides of the frame component (2) by bolts.

4. The static balance detection method for inertial system frame components according to claim 1, characterized in that: In step 4), the torque electric rotation speed is 10r / min-120r / min. In step 6), the maximum torque generated by forward and reverse rotation is weighted and averaged to eliminate system error. The difference in the maximum output torque at different speeds is compared. When the maximum torque deviation at different speeds is within 1%, the maximum torque at the lowest speed is taken. If the error is greater than 1%, the system is adjusted to reduce friction.

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