A measuring device and testing method for separation impulse eccentricity

Abstract

The present invention provides a device and method for measuring the eccentricity of a separation impulse. The device for measuring the eccentricity of a separation impulse comprises: a support column, a ball head, a ball socket adapted for the ball head, a separation body mounting flange, and a six-axis inertial measurement mechanism for measuring the eccentricity of the separation impulse. The ball socket is mounted on the top of the support column, the ball head is floatingly mounted in the ball socket, the separation body mounting flange is mounted on the ball head, the six-axis inertial measurement mechanism is mounted on the ball head, the support column is vertically arranged, the ball head is located above the ball socket, the separation body mounting flange is located above the ball head, and the six-axis inertial measurement mechanism is located between the ball head and the separation body mounting flange. A spherical concentric rotating concentric rotating structure with frictionless air flotation is used to achieve accurate testing of the eccentricity of the separation impulse.

Description

Technical Field

[0001] The present invention relates to the technical field of separation motion testing equipment, and in particular to a measuring device and a testing method for separation impulse eccentricity. Background Art

[0002] With the vigorous development of small satellite technology and commercial aerospace, there are various space separation bodies carried by microsatellites, cubic satellites, etc. in orbit. Among them, for small separation bodies and separation mechanisms, since the mass of microsatellites and cubic satellites is very small, the mass characteristics of the separation bodies are usually comparable to the mass and inertia of the platform. The impact of separation shock interference on satellite attitude is greater than that of large satellite platforms. Usually, microsatellite platforms do not have complex chemical propulsion systems, which will cause rolling in orbit.

[0003] Due to various process limitations, the separation impulse of the separation mechanism has eccentricity in angle and point of action. Most microsatellites or cubic satellites that rely solely on reaction wheels for attitude control have only tens of millinewtons (mNm-s). The separation shock not only causes a certain amount of impact interference, but when the eccentricity increases further, such as exceeding the reserve angular momentum of the wheels, it will directly cause the attitude of the microsatellite platform to continue to lose control and roll. Therefore, the eccentricity measurement and control of the separation mechanism are crucial to the impact on microsatellites, and a full-degree-of-freedom impulse eccentricity test must be performed before entering orbit.

[0004] Traditionally, suspension systems or horizontal free-fall schemes are more commonly used in aerospace systems. This form is widely used in the industry, but for separation systems with small mass and small impulse, not only is the degree of freedom in the horizontal plane limited, but there are also problems such as poor horizontal adjustment accuracy, large measurement inconsistency errors, and inability to measure deployment or flexible separation bodies. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a measuring device and a testing method for separation impulse eccentricity in view of the deficiencies in the prior art.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A device for measuring the eccentricity of a separation impulse, comprising: a support column, a ball head, a ball socket adapted for the ball head, a separation body mounting flange, and a six-axis inertial measurement mechanism for measuring the eccentricity of the separation impulse, the ball socket being mounted on the top of the support column, the ball head being floatingly mounted in the ball socket, the separation body mounting flange being mounted on the ball head, the six-axis inertial measurement mechanism being mounted on the ball head, the support column being vertically arranged, the ball head being located above the ball socket, the separation body mounting flange being located above the ball head, and the six-axis inertial measurement mechanism being located between the ball head and the separation body mounting flange.

[0007] The beneficial effects of the technical solution of the present invention are: the use of a frictionless air-floated spherical concentric rotating concentric rotating structure can achieve accurate testing of the separation impulse eccentricity. The rotation imposed on the separation body mounting flange by the instantaneous reaction of the separation of the separation body is the result of the inertial test, which does not change the state of the instantaneous separation of the separation body. At the moment when the separation action of the separation body ends, the inertial angle and angular velocity of the separation body are measured with high-speed sampling, which are used to record the rotational motion process of the measuring device under the combined action of the small offset state of the center of gravity and the center of rotation after the instantaneous disturbance of the separation action, and the calculation of the separation eccentric impulse is obtained according to the change of the kinematic process. The floating setting of the ball head allows the ball head to rotate and has three degrees of freedom, so the relevant data can be measured in one experiment. The six-axis inertial measurement mechanism is installed in the measuring device, and there is no need to install the six-axis inertial measurement mechanism on the separation body, so it will not affect the mass distribution of the separation body.

[0008] Furthermore, it also includes: a floating mechanism for adjusting the center of mass and the horizontality, and the floating mechanism is installed around the ball head so as to be slidable in the vertical direction and the horizontal direction.

[0009] The beneficial effect of adopting the above-mentioned further technical solution is: by adjusting the center of mass offset through the floating mechanism, accurate testing of the separation impulse eccentricity can be achieved. The floating mechanism is equivalent to a vertical pendulum, which combines the vertical pendulum with the ball head and ball socket air flotation system. By selecting the screw holes of the upper frame and the lower frame, the center of mass of the ball head and ball socket air flotation system is adjusted downward in steps and located below the center of the rotating sphere. Through the reaction of the separation body to the separation body mounting flange when the separation body leaves, the six-axis inertial measurement mechanism measures the corresponding three-axis acceleration, three-axis angle, and three-axis angular rate information. Based on the rotating structure of the ball head and ball socket, using the dynamic laws of rigid body kinematics and gravity, a micro-short-range, self-recovering two-dimensional pendulum system is constructed.

[0010] Furthermore, the floating mechanism includes: an upper frame, a lower frame for adjusting the center of mass and horizontality, and a plurality of inclined beams. The upper frame and the lower frame are both annular structures. The upper frame is arranged around the ball head. One end of the plurality of inclined beams is connected to the ball head, and the other end of the plurality of inclined beams is connected to the upper frame. The lower frame can be slidably installed at the bottom of the upper frame in the vertical and horizontal directions.

[0011] The beneficial effects of adopting this further technical solution are as follows: the floating mechanism acts as a vertical pendulum, combining the vertical pendulum with a ball-and-socket air flotation system. By selecting screw holes in the upper and lower frames, the center of mass of the ball-and-socket air flotation system is gradually adjusted downward, positioned below the center of the rotating sphere. The six-axis inertial measurement mechanism measures the corresponding three-axis acceleration, three-axis angle, and three-axis angular rate information through the reaction of the separation body on the separation body's mounting flange. Based on the rotating structure of the ball-and-socket, a micro-short-range, self-recovering two-dimensional pendulum system is constructed by utilizing the dynamic laws of rigid body kinematics and gravity. The vertical downward sliding of the lower frame lowers the center of mass of the measuring device, placing it below the center of rotation. This allows the measuring device to return to its original position after oscillation, while reducing but not completely eliminating gravitational interference. The suspended ball head acts as a pendulum-like structure. If the separation body is too large, the vertical offset of the separation body's center of gravity is compensated by adjusting the vertical displacement of the lower frame. By adjusting the counterweight of the separation body longitudinally, a suitable mass ratio is required, and the vertical travel of the two-dimensional adjustment stage is precisely adjusted to achieve micron-level center of gravity accuracy. If a tilt component occurs, horizontal adjustments are interspersed. Based on the offset longitudinal displacement setting, the oscillation period after longitudinal offset is measured. Based on the overall inertia after loading, dynamic methods are used to accurately measure the longitudinal displacement of the entire air flotation after loading.

[0012] Furthermore, the lower frame is connected to the upper frame through a plurality of two-dimensional adjustment platforms, and the lower frame is located below the upper frame.

[0013] The beneficial effects of adopting this further technical solution are: the floating mechanism acts as a vertical pendulum, combining the vertical pendulum with a ball-and-socket air flotation system. By selecting screw holes in the upper and lower frames, the center of mass of the ball-and-socket air flotation system can be gradually adjusted downward, positioned below the center of the rotating sphere. The short-range distance of the pendulum can be adjusted longitudinally via a two-dimensional adjustment platform. By setting the distance between the longitudinal center of mass and the center of the moving sphere, the oscillation period of dynamic motion is obtained, forming a vertical air flotation swing force system adjustable from a few microns to several hundred microns. The two-dimensional adjustment platform is used to adjust the lower frame up and down, thereby changing the center of mass of the suspension system. Adjustment in different directions can also change the horizontality of the separator's mounting flange. The distance between the upper and lower frames can be changed by turning a knob, and the position of the lower frame can be adjusted via the holes in the two-dimensional adjustment platform, ensuring adaptive adjustment of the separator's mass over a wide range and simultaneously facilitating vertical center of mass adjustment over a wide range. According to the horizontal tilt component of the lateral acceleration component of the digital six-axis inertial measurement mechanism on the measuring device, the horizontal position of the center of mass of the platform moving part and the measured separated body is adjusted by the horizontal adjustment platform on the frame and the displacement of the measuring device separated body; under the resistance of gravity and air film, longitudinal adjustment is achieved through the two-dimensional adjustment platform, and the adjustment accuracy depends on the weight ratio design of the counterweight on the two-dimensional adjustment platform and the output measurement accuracy of the six-axis inertial measurement mechanism.

[0014] Furthermore, the six-axis inertial measurement mechanism is connected to a battery pack for powering the six-axis inertial measurement mechanism, the battery pack is installed on the ball head, the battery pack is located above the ball head, and a wireless transmission device is integrated inside the six-axis inertial measurement mechanism.

[0015] The beneficial effect of adopting the above-mentioned further technical solution is as follows: the six-axis inertial measurement mechanism is fixed on the measurement device of the separation impulse eccentricity. As the separation body is released, it rotates with the separation body mounting flange to collect posture information, and can output the system's three-axis acceleration, three-axis angle, and three-axis angular rate information at high speed. The six-axis inertial measurement mechanism transmits real-time measurement and control data to an external processing system wirelessly, via Bluetooth point-to-point or WIFI transparent transmission, completely eliminating external influences such as bending moment and additional torque caused by the bending of the connected umbilical cable.

[0016] Furthermore, an air path interface for connecting to an air source is provided in the ball socket.

[0017] The beneficial effects of adopting the above-mentioned further technical solution are as follows: the air circuit interface can be directly connected to the gas source of compressed air, and an air film of about 10 microns is formed between the ball head and the socket through an external air or nitrogen gas source. Under the action of the air film between the ball head and the socket, the rotating system has a center of mass below the center of the ball. Therefore, compared with the commonly used ball head system for simulating on-track torque, its processing accuracy requirements are low, it can be processed and ground using common materials such as low-cost resins, the system leveling process is fast, and the cost is controllable. Between the ball head and the socket is an air film blown out by the air circuit interface, which puts the ball head and other devices in a suspended state, effectively reducing the interference of gravity and friction. The setting of the air circuit interface makes it easy for an external air source to blow air between the ball head and the socket to form an air film, thereby realizing the suspension and rotation of the ball head.

[0018] Furthermore, a gap is provided between the ball head and the ball socket, and a value range of the gap is 5-15 microns.

[0019] The beneficial effects of this further technical solution are: an external air or nitrogen source forms an air film approximately 10 microns thick between the ball head and socket. Because the center of mass of the rotating system is below the center of the ball, the system requires less machining precision than conventional ball head systems designed to simulate on-track torque. The system can be machined and ground from common materials such as low-cost resins, resulting in faster system leveling and manageable costs. The gap facilitates the formation of the air film, enabling the ball head to levitate and rotate.

[0020] Furthermore, the ball head is a hemispherical structure, the top of the ball socket is provided with a groove adapted to the ball head, the ball head is floatingly installed in the groove, and the ball head and the ball socket are both made of resin.

[0021] The beneficial effects of this further technical solution are: an external air or nitrogen source forms an air film approximately 10 microns thick between the ball head and socket. Because the center of mass of the rotating system is below the center of the ball, the system requires less machining precision than conventional ball head systems that simulate on-track torque. The system can be machined and ground from common materials such as low-cost resins, resulting in faster system leveling and manageable costs. The grooves also facilitate installation and maintenance of the ball head.

[0022] Furthermore, the separation body mounting flange is mounted on the ball head through a bracket, the top end of the bracket is connected to the separation body mounting flange, the bottom end of the bracket is connected to the top of the ball head, the bracket is located between the separation body mounting flange and the ball head, and the six-axis inertial measurement mechanism is located in the bracket.

[0023] The beneficial effect of adopting the above further technical solution is that the provision of the bracket facilitates the installation of the separation body mounting flange on the ball head, thereby facilitating the installation and maintenance of the six-axis inertial measurement mechanism.

[0024] In addition, the present invention also provides a method for testing separation impulse eccentricity. Based on any one of the above-mentioned separation impulse eccentricity measuring devices, the method for testing separation impulse eccentricity includes:

[0025] Install the separation body on the top of the separation body mounting flange;

[0026] The horizontality of the separation body mounting flange is adjusted through the six-axis inertial measurement mechanism;

[0027] Conduct separation tests;

[0028] The separation impulse eccentricity is measured by a six-axis inertial measurement mechanism.

[0029] The beneficial effect of adopting the technical solution of the present invention is: in order to test the small separation body that stores energy of the elastic element, after the separation body is connected to the separation body mounting flange, the center of gravity of the entire system needs to be adjusted laterally and offset longitudinally. The lateral adjustment of the center of gravity is achieved through the horizontal tilt angles output by the horizontal component of the six-axis inertial measurement mechanism, and the corresponding counterweight is used according to the horizontal component of the two-dimensional adjustment table to achieve horizontal adjustment and ensure the horizontality of the entire table surface.

[0030] Advantages of additional aspects of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is one of the structural schematic diagrams of the device for measuring separation impulse eccentricity provided by an embodiment of the present invention.

[0032] Figure 2 This is a second structural schematic diagram of the device for measuring separation impulse eccentricity provided in an embodiment of the present invention.

[0033] Figure 3 This is a third structural schematic diagram of the device for measuring separation impulse eccentricity provided in an embodiment of the present invention.

[0034] Figure 4 This is a fourth structural schematic diagram of the device for measuring separation impulse eccentricity provided in an embodiment of the present invention.

[0035] Figure 5 This is the fifth structural schematic diagram of the device for measuring separation impulse eccentricity provided in an embodiment of the present invention.

[0036] Figure 6 This is the sixth structural schematic diagram of the device for measuring separation impulse eccentricity provided in an embodiment of the present invention.

[0037] Figure 7 This is the seventh structural schematic diagram of the device for measuring separation impulse eccentricity provided in an embodiment of the present invention.

[0038] Figure 8 A schematic flow chart of a method for testing separation impulse eccentricity provided in an embodiment of the present invention.

[0039] Explanation of the accompanying numbers: 1. Support column; 2. Ball head; 3. Ball socket; 4. Separator mounting flange; 5. Six-axis inertial measurement mechanism; 6. Floating mechanism; 7. Upper frame; 8. Lower frame; 9. Inclined beam; 10. Two-dimensional adjustment table; 11. Battery pack; 12. Bracket. DETAILED DESCRIPTION

[0040] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0041] like Figures 1 to 7 As shown, an embodiment of the present invention provides a device for measuring the eccentricity of a separation impulse, which includes: a support column 1, a ball head 2, a ball socket 3 adapted to the ball head 2, a separation body mounting flange 4, and a six-axis inertial measurement mechanism 5 for measuring the eccentricity of the separation impulse, wherein the ball socket 3 is mounted on the top of the support column 1, the ball head 2 is floatingly mounted in the ball socket 3, the separation body mounting flange 4 is mounted on the ball head 2, and the six-axis inertial measurement mechanism 5 is mounted on the ball head 2, the support column 1 is vertically arranged, the ball head 2 is located above the ball socket 3, the separation body mounting flange 4 is located above the ball head 2, and the six-axis inertial measurement mechanism 5 is located between the ball head 2 and the separation body mounting flange 4.

[0042] The beneficial effects of the technical solution of the present invention are: the use of a frictionless air-floated spherical concentric rotating concentric rotating structure can achieve accurate testing of the separation impulse eccentricity. The rotation imposed on the separation body mounting flange by the instantaneous reaction of the separation of the separation body is the result of the inertial test, which does not change the state of the instantaneous separation of the separation body. At the moment when the separation action of the separation body ends, the inertial angle and angular velocity of the separation body are measured with high-speed sampling, which are used to record the rotational motion process of the measuring device under the combined action of the small offset state of the center of gravity and the center of rotation after the instantaneous disturbance of the separation action, and the calculation of the separation eccentric impulse is obtained according to the change of the kinematic process. The floating setting of the ball head allows the ball head to rotate and has three degrees of freedom, so the relevant data can be measured in one experiment. The six-axis inertial measurement mechanism is installed in the measuring device, and there is no need to install the six-axis inertial measurement mechanism on the separation body, so it will not affect the mass distribution of the separation body.

[0043] Among them, the model of the six-axis inertial measurement mechanism can be selected from commercial models. The selection of specific models is common knowledge and will not be elaborated here. It can also be customized according to actual conditions.

[0044] The six-axis inertial measurement unit (IMU) is fixed to an adapter flange (i.e., bracket) on the suspension mechanism. The bracket is mounted above and connected to the ball head. The mounting flange of the separator is mounted above and connected to the bracket. As the separator is released, the six-axis inertial measurement unit rotates with the suspension mechanism to collect attitude information. The six-axis inertial measurement unit is used to obtain relevant attitude data. Based on this known data, the attitude of the entire structure is adjusted using a two-dimensional adjustment table. The six-axis inertial measurement unit is connected to the adapter flange on the measurement device, which can be bolted.

[0045] The three degrees of freedom of the ball head means that the ball head can rotate forward and reverse horizontally in the ball socket, and can tilt up and down in the vertical direction and then rotate.

[0046] like Figures 1 to 7 As shown, further, it also includes: a floating mechanism 6 for adjusting the center of mass and the horizontality, and the floating mechanism 6 is installed around the ball head 2 so as to be slidable in the vertical direction and the horizontal direction.

[0047] The beneficial effect of adopting the above-mentioned further technical solution is: by adjusting the center of mass offset through the floating mechanism, accurate testing of the separation impulse eccentricity can be achieved. The floating mechanism is equivalent to a vertical pendulum, which combines the vertical pendulum with the ball head and ball socket air flotation system. By selecting the screw holes of the upper frame and the lower frame, the center of mass of the ball head and ball socket air flotation system is adjusted downward in steps and located below the center of the rotating sphere. Through the reaction of the separation body to the separation body mounting flange when the separation body leaves, the six-axis inertial measurement mechanism measures the corresponding three-axis acceleration, three-axis angle, and three-axis angular rate information. Based on the rotating structure of the ball head and ball socket, using the dynamic laws of rigid body kinematics and gravity, a micro-short-range, self-recovering two-dimensional pendulum system is constructed.

[0048] Among them, the entire suspension system (measuring device) rotates due to the rotation of the ball head. The ball head and the ball socket are approximately concentric, so the rotational swing process of the suspension system is equivalent to a vertical pendulum; the function of the ball socket is only to make the suspension system including the ball head suspended in the air.

[0049] like Figures 1 to 7 As shown, further, the floating mechanism 6 includes: an upper frame 7, a lower frame 8 for adjusting the center of mass and horizontality, and a plurality of inclined beams 9. The upper frame 7 and the lower frame 8 are both annular structures. The upper frame 7 is arranged around the ball head 2. One end of the plurality of inclined beams 9 is connected to the ball head 2, and the other end of the plurality of inclined beams 9 is connected to the upper frame 7. The lower frame 8 can be slidably installed at the bottom of the upper frame 7 in the vertical and horizontal directions.

[0050] The beneficial effects of adopting this further technical solution are as follows: the floating mechanism acts as a vertical pendulum, combining the vertical pendulum with a ball-and-socket air flotation system. By selecting screw holes in the upper and lower frames, the center of mass of the ball-and-socket air flotation system is gradually adjusted downward, positioned below the center of the rotating sphere. The six-axis inertial measurement mechanism measures the corresponding three-axis acceleration, three-axis angle, and three-axis angular rate information through the reaction of the separation body on the separation body's mounting flange. Based on the rotating structure of the ball-and-socket, a micro-short-range, self-recovering two-dimensional pendulum system is constructed by utilizing the dynamic laws of rigid body kinematics and gravity. The vertical downward sliding of the lower frame lowers the center of mass of the measuring device, placing it below the center of rotation. This allows the measuring device to return to its original position after oscillation, while reducing but not completely eliminating gravitational interference. The suspended ball head acts as a pendulum-like structure. If the separation body is too large, the vertical offset of the separation body's center of gravity is compensated by adjusting the vertical displacement of the lower frame. By adjusting the counterweight of the separation body longitudinally, a suitable mass ratio is required, and the vertical travel of the two-dimensional adjustment stage is precisely adjusted to achieve micron-level center of gravity accuracy. If a tilt component occurs, horizontal adjustments are interspersed. Based on the offset longitudinal displacement setting, the oscillation period after longitudinal offset is measured. Based on the overall inertia after loading, dynamic methods are used to accurately measure the longitudinal displacement of the entire air flotation after loading.

[0051] like Figures 1 to 7 As shown, further, the lower frame 8 is connected to the upper frame 7 through a plurality of two-dimensional adjustment platforms 10 , and the lower frame 8 is located below the upper frame 7 .

[0052] The beneficial effects of adopting this further technical solution are: the floating mechanism acts as a vertical pendulum, combining the vertical pendulum with a ball-and-socket air flotation system. By selecting screw holes in the upper and lower frames, the center of mass of the ball-and-socket air flotation system can be gradually adjusted downward, positioned below the center of the rotating sphere. The short-range distance of the pendulum can be adjusted longitudinally via a two-dimensional adjustment platform. By setting the distance between the longitudinal center of mass and the center of the moving sphere, the oscillation period of dynamic motion is obtained, forming a vertical air flotation swing force system adjustable from a few microns to several hundred microns. The two-dimensional adjustment platform is used to adjust the lower frame up and down, thereby changing the center of mass of the suspension system. Adjustment in different directions can also change the horizontality of the separator's mounting flange. The distance between the upper and lower frames can be changed by turning a knob, and the position of the lower frame can be adjusted via the holes in the two-dimensional adjustment platform, ensuring adaptive adjustment of the separator's mass over a wide range and simultaneously facilitating vertical center of mass adjustment over a wide range. According to the horizontal tilt component of the lateral acceleration component of the digital six-axis inertial measurement mechanism on the measuring device, the horizontal position of the center of mass of the platform moving part and the measured separated body is adjusted by the horizontal adjustment platform on the frame and the displacement of the measuring device separated body; under the resistance of gravity and air film, longitudinal adjustment is achieved through the two-dimensional adjustment platform, and the adjustment accuracy depends on the weight ratio design of the counterweight on the two-dimensional adjustment platform and the output measurement accuracy of the six-axis inertial measurement mechanism.

[0053] There's a gap between the upper and lower frames, with the top of the 2D adjustment platform connected to the upper frame and the bottom to the lower frame. The 2D adjustment platform is located on the outer walls of the upper and lower frames and is used to achieve relative displacement between the two frames, specifically horizontal or vertical movement of the lower frame relative to the upper frame. The structure and principles of the 2D adjustment platform are prior art and will not be elaborated on here.

[0054] like Figures 1 to 7 As shown, further, the six-axis inertial measurement mechanism 5 is connected to a battery pack 11 for powering the six-axis inertial measurement mechanism 5, the battery pack 11 is installed on the ball head 2, and the battery pack 11 is located above the ball head 2, and a wireless transmission device is integrated inside the six-axis inertial measurement mechanism 5.

[0055] The beneficial effect of adopting the above-mentioned further technical solution is as follows: the six-axis inertial measurement mechanism is fixed on the measurement device of the separation impulse eccentricity. As the separation body is released, it rotates with the separation body mounting flange to collect posture information, and can output the system's three-axis acceleration, three-axis angle, and three-axis angular rate information at high speed. The six-axis inertial measurement mechanism transmits real-time measurement and control data to an external processing system wirelessly, via Bluetooth point-to-point or WIFI transparent transmission, completely eliminating external influences such as bending moment and additional torque caused by the bending of the connected umbilical cable.

[0056] The structure and circuit of the wireless transmission device integrated inside the six-axis inertial measurement mechanism 5 belong to the existing technology and will not be described in detail here.

[0057] like Figures 1 to 7 As shown, further, the ball socket 3 is provided with an air path interface for connecting to an air source.

[0058] The beneficial effects of adopting the above-mentioned further technical solution are as follows: the air circuit interface can be directly connected to the gas source of compressed air, and an air film of about 10 microns is formed between the ball head and the socket through an external air or nitrogen gas source. Under the action of the air film between the ball head and the socket, the rotating system has a center of mass below the center of the ball. Therefore, compared with the commonly used ball head system for simulating on-track torque, its processing accuracy requirements are low, it can be processed and ground using common materials such as low-cost resins, the system leveling process is fast, and the cost is controllable. Between the ball head and the socket is an air film blown out by the air circuit interface, which puts the ball head and other devices in a suspended state, effectively reducing the interference of gravity and friction. The setting of the air circuit interface makes it easy for an external air source to blow air between the ball head and the socket to form an air film, thereby realizing the suspension and rotation of the ball head.

[0059] The air path interface passes through the ball socket and is located on the side wall of the ball socket. An air path connector can be installed at the air path interface, and the user can select the air path connector according to actual needs.

[0060] like Figures 1 to 7 As shown, further, a gap is provided between the ball head 2 and the ball socket 3, and the value range of the gap is 5-15 microns.

[0061] The beneficial effects of this further technical solution are: an external air or nitrogen source forms an air film approximately 10 microns thick between the ball head and socket. Because the center of mass of the rotating system is below the center of the ball, the system requires less machining precision than conventional ball head systems designed to simulate on-track torque. The system can be machined and ground from common materials such as low-cost resins, resulting in faster system leveling and manageable costs. The gap facilitates the formation of the air film, enabling the ball head to levitate and rotate.

[0062] The gap mentioned here refers to the gap between the ball head and the ball socket when the ball head floats when the air path interface is ventilated.

[0063] like Figures 1 to 7 As shown, further, the ball head 2 is a hemispherical structure, and the top of the ball socket 3 is provided with a groove adapted to the ball head 2, and the ball head 2 is floatingly installed in the groove. The ball head 2 and the ball socket 3 are both made of resin.

[0064] The beneficial effects of this further technical solution are: an external air or nitrogen source forms an air film approximately 10 microns thick between the ball head and socket. Because the center of mass of the rotating system is below the center of the ball, the system requires less machining precision than conventional ball head systems that simulate on-track torque. The system can be machined and ground from common materials such as low-cost resins, resulting in faster system leveling and manageable costs. The grooves also facilitate installation and maintenance of the ball head.

[0065] The groove may be a hemispherical groove, and the ball head may be a hemispherical structure.

[0066] like Figures 1 to 7 As shown, further, the separation body mounting flange 4 is installed on the ball head 2 through a bracket 12, the top end of the bracket 12 is connected to the separation body mounting flange 4, the bottom end of the bracket 12 is connected to the top of the ball head 2, the bracket 12 is located between the separation body mounting flange 4 and the ball head 2, and the six-axis inertial measurement mechanism 5 is located in the bracket 12.

[0067] The beneficial effect of adopting the above further technical solution is that the provision of the bracket facilitates the installation of the separation body mounting flange on the ball head, thereby facilitating the installation and maintenance of the six-axis inertial measurement mechanism.

[0068] The present invention performs vertical rotation offset on the three-axis air-floating rotation system of the existing satellite attitude control simulation system, utilizes the motion characteristics of the dynamic system for transformation, and designs a high-precision concentric rotation, center of mass offset separation mechanism impulse eccentricity test platform, that is, a separation impulse eccentricity measurement device, which overcomes the problems of the existing method and can realize the accurate test of separation impulse eccentricity.

[0069] The present invention is based on the actual needs of testing and can be applied not only to vertical separation tests of rigid objects, but also to flexible separation bodies such as fabrics. It has been applied to a rope net flexible separation test and achieved good results. The present invention combines the vertical pendulum with the ball head and ball socket air flotation system. By selecting the screw holes of the upper frame and the lower frame, the center of mass of the system (i.e., the device for measuring the eccentricity of the separation impulse) is adjusted downward step by step. It is located below the center of the rotating ball. The commonly used low-cost civilian components are processed and matched at a low cost to construct a concentrically rotating separation mechanism impulse eccentricity test platform, i.e., a device for measuring the eccentricity of the separation impulse. The measuring device has the following advantages:

[0070] The ball head and socket can be made of resin material. An air film of about 10 microns is formed between the ball head and socket through an external air or nitrogen gas source. Under the action of the air film between the ball head and socket, the center of mass of the rotating system is below the center of the ball. Therefore, compared with the commonly used ball head system for simulating on-track torque, the processing accuracy requirement is lower, and it can be processed and ground with common materials such as low-cost resin. The system leveling process is fast and the cost is controllable.

[0071] By mounting the separator on the upper separator mounting flange, this system (i.e., the separation impulse eccentricity measurement device) is used to test vertical separation on a time scale of hundreds of milliseconds. The rotation imposed on the separation impulse eccentricity measurement device by the instantaneous reaction of the separator separation is the result of inertial testing and does not change the instantaneous separation state of the separator. At the moment of separation, the inertial angle and angular velocity of the separator are sampled at high speed and recorded. The rotational motion of the measurement device under the combined effect of small center of gravity and center of rotation offsets after the separation is disturbed, and the separation eccentricity impulse is calculated based on the changes in the kinematic process. This system also overcomes the shortcomings of horizontal projection measurement that cannot adapt to deformation or stretching of flexible separators during deployment, as well as the aforementioned shortcomings of vertical suspension, such as the limited horizontal degrees of freedom and low test consistency when rotating in different directions. Through the reaction of the separator's departure on the measurement device, the measurement device measures the corresponding three-axis acceleration, three-axis angle, and three-axis angular rate information, and the calculation method is basically consistent with existing solutions. The measuring device of the present invention differs primarily from existing vertical suspension systems in that the ball head is floating and therefore rotatable, providing three degrees of freedom, enabling the measurement of relevant data in a single experiment. Furthermore, the present invention differs primarily from existing horizontal projection measurement systems in that a six-axis inertial measurement mechanism is installed within the measuring device to measure the reaction of the separation of the separated body, without requiring the six-axis inertial measurement mechanism to be mounted on the separated body, thereby unaffecting the mass distribution of the separated body. Because the six-axis inertial measurement mechanism only needs to measure three-axis rotational data to determine relevant data, its installation position does not interfere with the measurement.

[0072] Based on the rotating structure of a ball head and socket, this invention utilizes the kinematics of rigid bodies and the dynamic laws of gravity to construct a micro-short-distance, self-recovering two-dimensional pendulum system. Three-axis air-floating platforms are often used to simulate weightlessness in space. To eliminate the effects of gravity, the center of mass of the suspended system should coincide with the center of rotation. For measurement purposes, the present invention sets the system center of mass below the center of rotation. This reduces but does not completely eliminate gravitational interference, allowing the system to return to its original position after oscillation. The suspended ball head and other overall systems resemble pendulum structures. The micro-short distance, defined as the eccentricity between the system center of mass and the center of rotation, is not required to be zero. By adjusting the distance between the longitudinal center of mass and the center of the moving ball, the oscillation period of the dynamic motion is determined, forming a vertical air-floating swing force system adjustable from a few microns to several hundred microns. Except for the middle supporting column and ball socket, the upper frame, lower frame, separator mounting flange, two-dimensional adjustment platform, etc. connected to the ball head are all suspended. Between the ball head and the ball socket is an air film blown out by the air path interface, which makes the ball head and other devices suspended in the air, which can effectively reduce the interference of gravity and friction.

[0073] According to the composition of the movement, it is divided into three parts: (1) The fixed part on the ground is composed of a support column and a ball socket. The ball socket has an air path interface and can be directly connected to the gas source of compressed air; (2) The floating movement part is composed of a ball head with high smoothness and precision. The ball head is connected to a fixed upper frame through 8 inclined beams and connected to the lower frame through 8 commercial two-dimensional adjustment platforms on the sides. The purpose of the two-dimensional adjustment platform is to adjust the lower frame up and down, thereby changing the center of mass of the suspension system. At the same time, adjustment in different directions can also change the horizontality of the platform (separator mounting flange). The distance between the upper frame and the lower frame can be changed by the knob. The internal structure can be made of civilian products. The position of the lower frame can be adjusted by the hole position of the two-dimensional adjustment platform to ensure the adaptive adjustment of the mass of the separation body in a wide range, and at the same time, it can play the role of vertical center of mass adjustment in a wide range; (3) The motion measurement part on the two-dimensional adjustment platform includes a commercial standard 18650 lithium battery pack power supply and an inertial measurement unit (IMU) for measuring 6-axis output. The IMU is powered by a battery pack and is fixed to the suspension system. As the detached body is released, the IMU rotates with the suspension to collect attitude information. It can output the system's three-axis acceleration, three-axis angle, and three-axis angular rate information at high speed. The IMU transmits real-time measurement and control data to an external processing system wirelessly (Bluetooth point-to-point) or via Wi-Fi transparent transmission, completely eliminating external influences such as bending moment and additional torque caused by the bending of the connected umbilical cable.

[0074] According to the horizontal tilt component of the lateral acceleration component of the digital IMU on the measuring device, the horizontal position of the center of mass of the moving part of the platform and the measured separated body is adjusted through the horizontal adjustment platform on the side frame and the displacement of the separated body on the two-dimensional adjustment platform; under the resistance of gravity and air film, it is achieved through its longitudinal adjustment, and the accuracy of the adjustment depends on the weight ratio design of the counterweight on the two-dimensional adjustment platform and the output measurement accuracy of the inertial sensor IMU.

[0075] The two commonly used horizontal separation test methods each have different scopes of application. The innovations and key points of the present invention are reflected in the following aspects:

[0076] Through the vertical separation test of the direct separation mechanism, the eccentric characteristics of the impulse acting on the platform are directly tested; the spherical concentric rotation of the frictionless air float is combined with the two-dimensional pendulum motion in the form of macro; it is suitable for the separation and separation body test in rigid form, expanded form and flexible form.

[0077] like Figure 8 As shown, in addition, the present invention also provides a method for testing separation impulse eccentricity. Based on any one of the above-mentioned separation impulse eccentricity measuring devices, the method for testing separation impulse eccentricity includes:

[0078] S1. Install the separation body on the top of the separation body mounting flange;

[0079] S2. Adjust the horizontality of the mounting flange of the separation body through the six-axis inertial measurement mechanism;

[0080] S3, perform separation test;

[0081] S4. Measure the separation impulse eccentricity through a six-axis inertial measurement mechanism.

[0082] The beneficial effect of adopting the technical solution of the present invention is: in order to test the small separation body that stores energy of the elastic element, after the separation body is connected to the separation body mounting flange, the center of gravity of the entire system needs to be adjusted laterally and offset longitudinally. The lateral adjustment of the center of gravity is achieved through the horizontal tilt angles output by the horizontal component of the six-axis inertial measurement mechanism, and the corresponding counterweight is used according to the horizontal component of the two-dimensional adjustment table to achieve horizontal adjustment and ensure the horizontality of the entire table surface.

[0083] The measuring device can be a measuring platform, a test platform, a measuring system or a test system. In order to test a small separation body with energy storage of elastic elements, the separation body needs to be connected to the separation body mounting flange. The center of gravity of the entire system needs to be adjusted horizontally and offset vertically:

[0084] Lateral adjustment of the system's center of gravity: Lateral leveling is achieved by using the horizontal tilt and roll angles output by the IMU's horizontal component and by counterweighting the two-dimensional adjustment platform accordingly to ensure the horizontality of the entire platform (i.e., the measuring device and the separation mounting flange).

[0085] The system's center of gravity offset is adjusted in three steps in the longitudinal direction: (1) When the separation body is too large, the vertical offset of the separation body's center of gravity is compensated by adjusting the vertical displacement of the lower frame; (2) The system can achieve micron-level accuracy of the center of gravity by precisely adjusting the vertical stroke of the two-dimensional adjustment table that adjusts the separation body's counterweight (which needs to be equipped with a suitable mass ratio); if a tilting component occurs, horizontal adjustment needs to be interspersed. (3) According to the offset longitudinal displacement setting, the oscillation period after the longitudinal offset is measured, and according to the overall inertia after loading, the dynamic method is used to obtain the precise measurement of the longitudinal displacement of the entire air flotation after loading.

[0086] Different free bodies (i.e., separated bodies or loads) are placed on the platform. First, according to the IMU measurement, the control console can be adjusted based on the measurement information to ensure the horizontality of the system platform. Once the horizontality is met, the center of mass of the suspension system and the center of rotation are on the same vertical line. The next step is longitudinal adjustment. As mentioned above, the center of mass of the suspension system is required to be slightly lower than the center of rotation. This can achieve self-recovery while eliminating some gravity interference and making it more stable. The specific amount of longitudinal adjustment depends on the actual situation. In the specific experiment, it can be changed in real time according to the swing period to obtain satisfactory experimental results. Among them, the suspension system includes a ball head, a separated body mounting flange, a six-axis inertial measurement mechanism, a floating mechanism, an upper frame, a lower frame, an inclined beam, a two-dimensional adjustment table, a battery pack, and a bracket.

[0087] After the adjusted system has achieved the set longitudinal offset, the corresponding separation test can be carried out. The test measurement data can be processed and compared using the following two methods:

[0088] Direct method: The separation weight eccentricity is obtained by directly multiplying the gyro's angular velocity reading by the system inertia. However, due to the influence of the separation shock, the elastic dynamics of the entire air flotation system are disturbed by the high-frequency oscillation of the impact. The angular velocity obtained by IMU measurement has many oscillation factor errors due to factors such as zero bias and angular velocity measurement.

[0089] Dynamic method: Based on the integral form of the differential equation solution of the dynamic system of concentric two-dimensional oscillatory motion, the gyroscope angle data sequence is used for processing; the gyroscope angle data is the integral link of the angular velocity, which reduces the influence of the system noise. Moreover, since it is the amplitude data of the oscillation process, the separation eccentricity data of the separation body is obtained according to the angular momentum of the system.

[0090] The direct and dynamic methods described above are essentially similar to existing technologies, with the parameters and measurements being consistent. These methods are state-of-the-art, and those skilled in the art will readily understand how to process and calculate the data, so we will not elaborate on them here. The present invention focuses on improving the corresponding measurement environment and conditions, such as reaction, and enabling simultaneous measurement of multiple degrees of freedom.

[0091] The present invention designs a measuring device with a center offset suspended above the air film, utilizes the horizontal adjustment and longitudinal center of gravity offset provided on the two-dimensional adjustment table, and through a single experiment, can measure the entire eccentric impulse component of the separation impulse eccentricity of a general separation system in the longitudinal or near-longitudinal direction relative to the center reference point of the installation.

[0092] In the aerospace field, with the development of commercial aerospace and micro-satellite technology, elastic energy storage micro-separation mechanisms using pyrotechnics or hot knife locking have been widely used, such as the in-orbit separation of micro-aircraft such as nanosatellites and cubic satellites, the separation of tethered satellites from their parent satellites, the separation of space debris capture nets from satellite platforms, the separation of re-entry vehicle separation bodies from satellite platforms, etc. The separation test can cover small and medium-sized separation bodies of rigidity and flexibility of tens of kilograms and kilograms.

[0093] By setting the longitudinal eccentricity range, a 10 -2 ~10 2 Testing of different types of separations with a wide range of eccentricity characteristics in Newton-second-millimeters.

[0094] Full-degree-of-freedom simulation tests can be conducted using weightless aircraft and microgravity drop towers. my country has few aircraft and corresponding experimental opportunities for weightless zero-gravity flight. Zero-gravity flights abroad must be applied for through international cooperation. Their free-flight time can reach 20 seconds, but commercial companies rarely have access to flight opportunities. my country's microgravity drop towers, utilizing large-scale national scientific experimental facilities such as these, can conduct motion tests of separation characteristics with full degrees of freedom. The free-fall time within the experimental chamber of the drop tower is relatively short, only a few seconds, allowing for the release of all degrees of freedom. However, the chamber's space is not suitable for separation testing of flexible objects.

[0095] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A device for measuring separation impulse eccentricity, characterized in that: include: A support column, a ball head, a ball socket adapted to the ball head, a separator mounting flange, and a six-axis inertial measurement mechanism for measuring the eccentricity of the separation impulse, wherein the ball socket is mounted on the top of the support column, the ball head is floatingly mounted in the ball socket, the separator mounting flange is mounted on the ball head, and the six-axis inertial measurement mechanism is mounted on the ball head. The support column is vertically arranged, the ball head is located above the ball socket, the separator mounting flange is located above the ball head, and the six-axis inertial measurement mechanism is located between the ball head and the separator mounting flange; and further comprising: a floating mechanism for adjusting the center of mass and horizontality, the floating mechanism being mounted on the ball head around and slidable in the vertical and horizontal directions. Around; the floating mechanism includes: an upper frame, a lower frame for adjusting the center of mass and horizontality, and a plurality of inclined beams, the upper frame and the lower frame are both annular structures, the upper frame is arranged around the ball head, one end of the plurality of inclined beams is connected to the ball head, and the other end of the plurality of inclined beams is connected to the upper frame, and the lower frame can be slidably installed on the bottom of the upper frame along the vertical and horizontal directions; the separator mounting flange is installed on the ball head through a bracket, the top end of the bracket is connected to the separator mounting flange, the bottom end of the bracket is connected to the top of the ball head, the bracket is located between the separator mounting flange and the ball head, and the six-axis inertial measurement mechanism is located in the bracket.

2. The device for measuring separation impulse eccentricity according to claim 1, characterized in that: The lower frame is connected to the upper frame through a plurality of two-dimensional adjustment platforms, and the lower frame is located below the upper frame.

3. The device for measuring separation impulse eccentricity according to claim 1, characterized in that: The six-axis inertial measurement mechanism is connected to a battery pack for powering the six-axis inertial measurement mechanism. The battery pack is installed on the ball head and located above the ball head. A wireless transmission device is integrated inside the six-axis inertial measurement mechanism.

4. The device for measuring separation impulse eccentricity according to claim 1, characterized in that: An air path interface for connecting to an air source is provided in the ball socket.

5. The device for measuring separation impulse eccentricity according to claim 1, characterized in that: A gap is provided between the ball head and the ball socket, and a value range of the gap is 5-15 microns.

6. The device for measuring separation impulse eccentricity according to claim 1, characterized in that: The ball head is a hemispherical structure, and a groove adapted to the ball head is provided on the top of the ball socket. The ball head is floatingly installed in the groove. The ball head and the ball socket are both made of resin.

7. A method for testing separation impulse eccentricity, characterized in that: Based on the device for measuring separation impulse eccentricity according to any one of claims 1 to 6, the method for testing separation impulse eccentricity includes: Install the separation body on the top of the separation body mounting flange; The horizontality of the separation body mounting flange is adjusted through the six-axis inertial measurement mechanism; Conduct separation tests; The separation impulse eccentricity is measured by a six-axis inertial measurement mechanism.

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