A rotating scanning plume density measurement device for electric thrusters

Abstract

The application discloses a rotating scanning type plume density measuring device for an electric thruster, which comprises a hollow rotating module, a linear module, a micron tungsten wire probe, a vacuum chamber, a control module and a position detection module; the control module is further used for controlling the linear module to drive the micron tungsten wire probe to perform radial scanning according to detection information of the position detection module; the control module is further used for controlling the hollow rotating module to drive the micron tungsten wire probe to rotate, so that radial scanning is repeatedly completed at different angles; the control module is further used for matching the collected plume current signal with corresponding radial position information and angular position information, and converting the information into a plume current density two-dimensional cloud picture; the rotating scanning type plume density measuring device for the electric thruster is compact in structure, the scanning boundary is controllable, and radial scanning and angular scanning can be simultaneously realized.

Description

Technical Field

[0001] This invention relates to the field of measuring equipment technology, and specifically to a rotary scanning plume density measuring device for electric thrusters. Background Technology

[0002] Metal liquid field emission electric propulsion technology is a micro-thrust electric propulsion technology that utilizes liquid metal to form a Taylor cone under the action of a strong electric field and generate ion emission.

[0003] The spatial distribution of the plume formed during thruster operation directly affects the thrust magnitude, thrust direction, plume divergence angle, launch stability, and the risk of charge contamination and deposition between the thruster and other spacecraft components. Therefore, accurate measurement of the FEEP thruster plume density distribution is a crucial step in thruster performance evaluation, structural optimization, and life verification.

[0004] Existing FEEP plume measurement methods typically include fixed Faraday probe arrays and single-point moving probes. While these methods can obtain information on plume current or density distribution to some extent, they still have the following limitations: 1. Fixed multi-probe arrays have complex structures. Multiple probes or Faraday cups require separate wiring and connection to independent acquisition channels, resulting in large device size, complex manufacturing and assembly, difficulties in wiring within the vacuum chamber, and limitations on spatial resolution due to probe spacing.

[0005] 2. Although traditional single-probe moving scans have a relatively simple structure, they can usually only obtain data from one or a few scan lines. To obtain a complete two-dimensional distribution, a two-dimensional moving platform or multiple repeated movements are required, resulting in a long testing time and high requirements for motor displacement accuracy and repeatability in a vacuum environment. Summary of the Invention

[0006] The purpose of this invention is to provide a rotary scanning plume density measurement device for electric thrusters, which has a compact structure, controllable scanning boundaries, and can simultaneously achieve radial and angular scanning.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: A rotary scanning plume density measurement device for electric thrusters includes: a hollow rotary module, a linear module, a micron-sized tungsten wire probe, a vacuum chamber, a control module, and a position detection module.

[0008] The central area of ​​the hollow rotating module is provided with an assembly hole for mounting the thruster.

[0009] The linear module is fixedly disposed on the hollow rotating module, and the linear module is configured to be driven to rotate by the hollow rotating module; The micron-sized tungsten wire probe is used to collect plume current signals. The micron-sized tungsten wire probe is fixedly arranged on the linear module, and the linear module is used to drive the displacement of the micron-sized tungsten wire probe. The micron-sized tungsten wire probe is installed inside the vacuum chamber; Multiple of the aforementioned position detection modules are used to acquire the radial position information of the micron-sized tungsten wire probe.

[0010] The hollow rotating module, the linear module, the micron-sized tungsten wire probe, and the position detection module are all electrically connected to the control module.

[0011] The control module is used to acquire the angular position information of the hollow rotating module.

[0012] The control module is also used to control the linear module to drive the micron-sized tungsten wire probe to perform radial scanning based on the detection information of the position detection module.

[0013] The control module is also used to control the hollow rotating module to drive the micron-sized tungsten wire probe to rotate, so as to repeatedly complete the radial scan at different angles.

[0014] The control module is also used to match the acquired plume current signal with the corresponding radial and angular position information, and convert the information into a two-dimensional cloud map of plume current density.

[0015] In at least one embodiment of the present disclosure, the control module is further configured to record the plume current signal collected by the micron-sized tungsten wire probe, the radial position information collected by the position detection module, and the angular position information of the hollow rotating module.

[0016] The rotary scanning plume density measuring device for an electric thruster provided in at least one embodiment of this disclosure further includes a support frame and a connecting frame.

[0017] The support frame is used to support the hollow rotating module.

[0018] The connecting frame is configured to be fixedly connected to the linear module.

[0019] The support frame is configured to be fixedly connected to the hollow rotating module.

[0020] The connecting frame is fixedly disposed at the output end of the hollow rotating module so that the linear module rotates following the hollow rotating module.

[0021] In at least one embodiment of the present disclosure, a rotary scanning plume density measuring device for an electric thruster is provided, wherein the position detection module includes a first photoelectric limit switch, a second photoelectric limit switch, and a light shield.

[0022] The first photoelectric limit switch and the second photoelectric limit switch are both fixedly disposed on one side of the linear module, and the light-shielding plate is fixedly disposed on the movable part of the linear module.

[0023] The first photoelectric limit switch and the second photoelectric limit switch are used to obtain the position information of the light-shielding sheet.

[0024] In at least one embodiment of the present disclosure, a rotary scanning plume density measuring device for an electric thruster is provided, wherein the hollow rotary module includes a stepper motor and a hollow rotary platform.

[0025] The output end of the stepper motor is connected to the input end of the hollow rotary platform.

[0026] In at least one embodiment of the present disclosure, a rotary scanning plume density measuring device for an electric thruster is provided, wherein the micron-sized tungsten wire probe comprises a micron-sized tungsten wire and a tungsten wire support.

[0027] Both ends of the micron-sized tungsten wire are fixedly connected to the tungsten wire support, and the micron-sized tungsten wire is in a taut state.

[0028] In at least one embodiment of the present disclosure, a rotary scanning plume density measuring device for an electric thruster is provided, wherein the micron-sized tungsten filament is configured perpendicular to the linear module.

[0029] In at least one embodiment of the present disclosure, a rotary scanning plume density measuring device for an electric thruster is provided, wherein the length of the micron-sized tungsten wire is greater than the diameter of the mounting hole.

[0030] The rotary scanning plume density measuring device for an electric thruster provided in at least one embodiment of this disclosure further includes a power supply.

[0031] The power supply is used to provide stable power to the hollow rotating module, the linear module, the position detection module, and the control module.

[0032] The beneficial effects of this invention are as follows: 1. This invention uses a micron-sized tungsten wire probe to scan the plume. Compared with a fixed multi-probe array, it has a simpler structure, higher spatial resolution, and is suitable for measuring the plume of FEEP thrusters with small scale and concentrated density distribution.

[0033] 2. This invention uses a linear module to drive a micron-sized tungsten wire probe for radial scanning, which improves the positioning accuracy and repeatability of the scanning process and can effectively reduce manual adjustment errors.

[0034] 3. This invention achieves angular rotation through a hollow rotating module, enabling the tungsten wire probe to repeatedly complete radial scanning at different angles, thereby obtaining the two-dimensional distribution characteristics of the plume, rather than being limited to the measurement results on a single radial line. It can completely and reconstruct the two-dimensional distribution of the plume with high resolution.

[0035] 4. This invention converts the spatial position relationship of the tungsten wire probe into a detectable limit signal through a position detection module, thereby achieving precise control of the scanning start point, end point and return position, ensuring that each scan can cover the entire plume area.

[0036] 5. This invention can achieve plume scanning within the range of 0° to 180°, making it suitable for long-term automated testing.

[0037] 6. The present invention has a compact structure and clear adjustment logic. It can be used for laboratory plume measurement of liquid metal indium FEEP thrusters, and can also be extended to the spatial distribution testing of other micro-thrusters, ion sources, electron sources or charged particle beams. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This invention relates to a component connection frame for a rotary scanning plume density measuring device for an electric thruster.

[0040] Figure 2 This is a side view of a rotary scanning plume density measuring device for an electric thruster according to the present invention.

[0041] Figure 3 This is a schematic diagram showing the component connection between the micron-sized tungsten wire probe and the control module.

[0042] In the picture: 10. Hollow rotary module; 11. Stepper motor; 12. Hollow rotary platform; 20. Linear module; 30. Micrometer-scale tungsten wire probe; 31. Micrometer-scale tungsten wire; 32. Tungsten wire support; 40. Control module; 41. Host computer; 42. Data acquisition card; 43. Signal receiver; 50. Position detection module; 51. First photoelectric limit switch; 52. Second photoelectric limit switch; 53. Light shield; 60. Support frame; 70. Connecting bracket. Detailed Implementation

[0043] The technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments, not all embodiments.

[0044] Example like Figures 1 to 3 As shown, this embodiment provides a rotary scanning plume density measurement device for an electric thruster, including a hollow rotary module 10, a linear module 20, a micron-sized tungsten wire probe 30, a vacuum chamber (not shown), a control module 40, a position detection module 50, a support frame 60, a connecting frame 70, and a power supply (not shown). The hollow rotary module 10, linear module 20, micron-sized tungsten wire probe 30, and position detection module 50 are all electrically connected to the control module 40. The power supply provides stable power to the hollow rotary module 10, linear module 20, position detection module 50, and control module 40.

[0045] In this embodiment, the hollow rotating module 10 is provided with mounting holes (not shown), which are used to mount the thruster.

[0046] Specifically, the hollow rotary module 10 includes a stepper motor 11 and a hollow rotary platform 12. The output terminal of the stepper motor 11 is connected to the input terminal of the hollow rotary platform 12. The mounting hole is located in the central region of the hollow rotary platform 12.

[0047] In this embodiment, the micron-sized tungsten wire probe 30 is used to collect plume current signals. The micron-sized tungsten wire probe 30 is fixedly configured on the linear module 20, and the linear module 20 is used to drive the displacement of the micron-sized tungsten wire probe 30. The micron-sized tungsten wire probe 30 is installed inside the vacuum chamber.

[0048] Specifically, the micron-sized tungsten wire probe 30 includes a micron-sized tungsten wire 31 and a tungsten wire support 32. Both ends of the micron-sized tungsten wire 31 are fixedly connected to the tungsten wire support 32, and the micron-sized tungsten wire 31 is in a taut state.

[0049] Specifically, the micron-sized tungsten wire 31 is configured to be perpendicular to the linear module 20; the length of the micron-sized tungsten wire 31 is greater than the diameter of the mounting hole.

[0050] In this embodiment, the position detection module 50 is used to collect the radial position information of the micron-sized tungsten wire probe 30.

[0051] The control module 40 is used to acquire the angular position information of the hollow rotating module 10.

[0052] The control module 40 is also used to control the linear module 20 to drive the micron-sized tungsten wire probe 30 to perform radial scanning based on the detection information from the position detection module 50.

[0053] The control module 40 is also used to control the hollow rotating module 10 to drive the micron-sized tungsten wire probe 30 to rotate, so as to repeatedly complete the radial scan at different angles.

[0054] The control module 40 is also used to match the acquired plume current signal with the corresponding radial and angular position information, and convert the information into a two-dimensional cloud map of plume current density.

[0055] The control module 40 is also used to record the plume current signal collected by the micron-sized tungsten wire probe 30, the radial position information collected by the position detection module 50, and the angular position information of the hollow rotating module 10.

[0056] In this embodiment, the support frame 60 is used to support the hollow rotating module 10; the connecting frame 70 is configured to be fixedly connected to the linear module 20; and the support frame 60 is configured to be fixedly connected to the hollow rotating module 10.

[0057] The connecting frame 70 is fixedly disposed at the output end of the hollow rotating module 10, so that the linear module 20 rotates with the output end of the hollow rotating module 10.

[0058] In this embodiment, the position detection module 50 includes a first photoelectric limit switch 51, a second photoelectric limit switch 52, and a light-shielding plate 53; the first photoelectric limit switch 51 and the second photoelectric limit switch 52 are both fixedly disposed on one side of the linear module 20, and the light-shielding plate 53 is fixedly disposed on the tungsten wire support 32; the first photoelectric limit switch 51 and the second photoelectric limit switch 52 are used to obtain the position information of the light-shielding plate 53; the light-shielding plate 53 is a metal light-shielding plate.

[0059] In this embodiment, the control module 40 includes a host computer 41, a data acquisition card 42, and a signal receiver 43. The data acquisition card 42 and the signal receiver 43 are connected; the host computer 41 and the data acquisition card 42 are connected.

[0060] The following describes the measurement method of the rotary scanning plume density measuring device for electric thrusters provided in this embodiment, specifically including the following steps: 1) Installation and initial alignment of the device.

[0061] Install the FEEP thruster into the mounting hole of the hollow rotating platform, ensuring the porous tungsten needle emitter of the thruster is coaxial with the central axis of the hollow rotating platform. Adjust the tungsten wire support 32 to align the micron-sized tungsten wire with the center of the hollow rotating platform at multiple angles. Adjust the positions of the first photoelectric limit switch 51 and the second photoelectric limit switch 52 according to the position of the light-shielding plate 53 on the tungsten wire support 32, so that the midpoint of the two photoelectric limit switches corresponds to the reference position of the light-shielding plate 53, thereby completing the overall alignment of the device.

[0062] 2) Initial position setting.

[0063] The linear control module 20 drives the light-shielding plate 53 to move above the first photoelectric limit switch 51. At this time, the micron-sized tungsten wire probe 30 is located on one side of the thruster plume scanning area, which serves as the starting position for the first radial scan.

[0064] 3) First radial scan.

[0065] The linear module 20 moves at a constant speed and direction. The light-shielding plate 53 moves from above the first photoelectric limit switch 51 towards the second photoelectric limit switch 52, simultaneously driving the micron-sized tungsten wire probe 30 radially through the FEEP thruster plume region. When the light-shielding plate 53 passes the first photoelectric limit switch 51, the control module 40 does not execute a stop action, allowing the linear module 20 to continue moving towards the second photoelectric limit switch 52. When the light-shielding plate 53 continues to move and triggers the second photoelectric limit switch 52, the control module 40 reads the signal from the second photoelectric limit switch 52 and then controls the linear module 20 to decelerate and stop. During the process of passing the first photoelectric limit switch 51 and the second photoelectric limit switch 52, the micron-sized tungsten wire probe 30 completes a complete radial scan of the thruster plume. During the movement, the control module 40 reads the photoelectric limit switch signals, movement speed, and movement direction to determine the position of the tungsten wire. Furthermore, during the movement, the control module 40 records the photoelectric limit switch signals and the current signal collected by the tungsten wire.

[0066] 4) Angular rotation.

[0067] After completing one radial scan, the hollow rotating module 10 is driven to rotate 5°. Since the linear module 20, the tungsten wire support 32, and the micron-sized tungsten wire probe 30 all rotate together with the hollow rotating module 10, the scanning direction of the micron-sized tungsten wire probe 30 changes by 5° relative to the thruster emitter axis. The control module 40 records the angular rotation change.

[0068] 5) Reverse radial scan.

[0069] After the hollow rotating module 10 completes a 5° rotation, the linear module 20 moves in the opposite direction, and the light-shielding plate 53 moves from bottom to top, passing sequentially through the second photoelectric limit switch 52 and the first photoelectric limit switch 51. When the light-shielding plate 53 passes the first photoelectric limit switch 51, the control module 40 controls the linear module 20 to stop moving, completing the reverse scanning or return positioning at that angle. Subsequently, the hollow rotating module 10 is driven to rotate 5° to enter the next angular position.

[0070] 6) Cyclic scanning.

[0071] The radial scan, limit detection, angular rotation, and reverse motion processes are repeated until the hollow rotating module 10 accumulates a rotation angle of 180°. Since the plume distribution is usually symmetrical about the thruster axis, the radial and angular distribution information of the thruster plume on a complete 360° cross section can be obtained by scanning within the range of 0° to 180°.

[0072] 7) Data collection.

[0073] During the cyclic scanning process, the control module 40 records the voltage changes of the photoelectric limit switch and the current data of the micron-sized tungsten wire probe 30 throughout the entire process.

[0074] 8) Data processing.

[0075] The plume current signal collected by the micron-sized tungsten wire probe 30 at each angular position is matched with the corresponding radial and angular positions, and converted into a two-dimensional cloud map of plume current density by filtering back projection method.

[0076] Although embodiments of this application have been shown and described above, the scope of protection of this invention is not limited thereto. Any variations or substitutions that can be conceived without inventive effort should be covered within the scope of protection of this invention. Unless expressly stated otherwise, no element, action or instruction used herein should be construed as critical or necessary.

Claims

1. A rotary scanning plume density measuring device for an electric thruster, characterized in that, include: A hollow rotating module has an assembly hole in its central area, which is used to mount a thruster. A linear module is fixedly disposed on the hollow rotating module, and the linear module is configured to be driven to rotate by the hollow rotating module; A micron-sized tungsten wire probe is used to collect plume current signals. The micron-sized tungsten wire probe is fixedly disposed on the linear module, and the linear module is used to drive the displacement of the micron-sized tungsten wire probe. A position detection module is used to collect the radial position information of the micron-sized tungsten wire probe; as well as Control module; The hollow rotating module, the linear module, the micron-sized tungsten wire probe, and the position detection module are all electrically connected to the control module; The control module is used to acquire the angular position information of the hollow rotating module; The control module is also used to control the linear module to drive the micron-sized tungsten wire probe to perform radial scanning based on the detection information of the position detection module. The control module is also used to control the hollow rotating module to drive the micron-sized tungsten wire probe to rotate, so as to repeatedly complete the radial scan at different angles; The control module is also used to match the acquired plume current signal with the corresponding radial and angular position information, and convert the information into a two-dimensional cloud map of plume current density.

2. The rotary scanning plume density measuring device for an electric thruster according to claim 1, characterized in that, The control module is also used to record the plume current signal collected by the micron-sized tungsten wire probe, the radial position information collected by the position detection module, and the angular position information of the hollow rotating module.

3. The rotary scanning plume density measuring device for an electric thruster according to claim 1, characterized in that, Also includes: Support frame for supporting the hollow rotating module; as well as The connecting bracket is configured to be fixedly connected to the linear module; The support frame is configured to be fixedly connected to the hollow rotating module; The connecting frame is fixedly disposed at the output end of the hollow rotating module so that the linear module rotates following the hollow rotating module.

4. The rotary scanning plume density measuring device for an electric thruster according to claim 3, characterized in that, The position detection module includes a first photoelectric limit switch, a second photoelectric limit switch, and a light shield; The first photoelectric limit switch and the second photoelectric limit switch are both fixedly disposed on one side of the linear module, and the light shield is fixedly disposed on the movable part of the linear module; The first photoelectric limit switch and the second photoelectric limit switch are used to obtain the position information of the light-shielding sheet.

5. A rotary scanning plume density measuring device for an electric thruster according to claim 1, characterized in that, The hollow rotating module includes a stepper motor and a hollow rotating platform; The output end of the stepper motor is connected to the input end of the hollow rotary platform.

6. The rotary scanning plume density measuring device for an electric thruster according to claim 1, characterized in that, The micron-sized tungsten wire probe comprises a micron-sized tungsten wire and a tungsten wire support; Both ends of the micron-sized tungsten wire are fixedly connected to the tungsten wire support, and the micron-sized tungsten wire is in a taut state.

7. A rotary scanning plume density measuring device for an electric thruster according to claim 6, characterized in that, The micron-sized tungsten filament is configured perpendicular to the linear module.

8. A rotary scanning plume density measuring device for an electric thruster according to claim 6, characterized in that, The length of the micron-sized tungsten wire is greater than the diameter of the mounting hole.

9. A rotary scanning plume density measuring device for an electric thruster according to claim 1, characterized in that, Also includes: The power supply is used to provide stable power to the hollow rotating module, linear module, position detection module, and control module.

10. A rotary scanning plume density measuring device for an electric thruster according to claim 1, characterized in that, Also includes: The vacuum chamber contains the micron-sized tungsten wire probe.

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