One-dimensional directional precise adjustable large-mass optical load gravity unloading device

Abstract

The invention discloses a one-dimensional pointing precision adjustable large-mass optical load gravity unloading device, and belongs to the technical field of optical engineering and precision machine.The one-dimensional pointing precision adjustable large-mass optical load gravity unloading device comprises a fixed base, a fixed frame is arranged on the fixed base, a one-dimensional precision rotating mechanism is arranged on the fixed frame, and the one-dimensional precision rotating mechanism comprises a one-dimensional rotating shaft; the one-dimensional rotating shafts are symmetrically arranged in the fixing frame, and a large-mass optical load is arranged between the two one-dimensional rotating shafts. According to the one-dimensional directional precision adjustable gravity unloading device for the large-mass optical load, the gravity unloading of the large-mass optical load is realized, and the precision directional adjustment performance of the large-mass optical load in the one-dimensional direction is not influenced at all; therefore, the simulation test of the high-precision pointing adjustment performance of the large-mass optical load on the ground can be realized.

Description

Technical Field

[0001] The invention relates to the fields of optical engineering and precision mechanical technology, and in particular to a one-dimensionally pointing, precisely adjustable, large-mass optical load gravity unloading device. Background Art

[0002] In some typical space application tasks such as space gravitational wave detection and precision optical remote sensing, precision drivers are needed to drive large-mass optical payloads to perform angular deflection around one-dimensional or two-dimensional precision rotation axes, so as to achieve precise adjustment of the spatial pointing direction of the large-mass optical payload in one-dimensional or two-dimensional directions.

[0003] For example, in a typical space gravitational wave detection mission, it is necessary to form an intersatellite laser ranging interferometer between multiple satellites to accurately measure the distance change between long-distance satellites and then calculate the gravitational wave data; among them, the intersatellite laser ranging interferometer measurement optical path on each satellite is fixedly connected to form a large-mass optical payload of about 80kg, and the pointing direction of the large-mass payload needs to be precisely adjusted in two dimensions to realize the scanning and capture function of the intersatellite laser beam and the precise adjustment of the pointing direction of the intersatellite laser beam during scientific measurement. The adjustment range of the two-dimensional pointing reaches ±5mrad, and the adjustment sensitivity is better than 10nrad. In a typical precision optical remote sensing space application mission, it is necessary to adjust the pointing direction of a large-mass optical remote sensing camera weighing tens of kilograms, accurately align it with the target area and keep tracking, and the pointing alignment and tracking accuracy are required to reach the micro-arc level.

[0004] In the above-mentioned space missions, these large-mass optical payloads work in a microgravity environment after entering orbit with the spacecraft. Therefore, when a precision driver is used to drive the large-mass optical payload to deflect around a one-dimensional or two-dimensional precision axis, the precision axis is only affected by the driving force or torque generated by the driver, and is not affected by the gravity of the large-mass optical payload itself. However, the assembly and testing of such large-mass optical payloads are all carried out in a ground gravity environment. In order to test its high-precision pointing adjustment performance at the micro-radian to nano-radian level around the precision axis, it is necessary to unload the gravity of the large-mass optical payload in the ground gravity environment to avoid the gravity acting on the precision axis, and it is necessary to avoid the gravity unloading device or mechanism from affecting the pointing adjustment performance, so as to ensure that the high-precision pointing adjustment performance of the large-mass optical payload in the space microgravity environment can be accurately and reliably tested in the ground environment.

[0005] The current gravity unloading methods are divided into two categories: active gravity compensation and passive gravity compensation. Active gravity compensation uses sensors and actuators to monitor and adjust the telescope structure in real time to compensate for changes caused by gravity. The compensation accuracy is high, but the structure is complex and easy to damage, which is not suitable for space exploration missions. Passive gravity compensation uses springs, pneumatic devices, suspension wires, etc. to partially offset the impact of gravity on the detector. It can be subdivided into drop tower method, parabola method, water flotation method, air flotation method, suspension method, etc. The drop tower method and parabola method are to make the experimental device do free fall or horizontal projection to achieve a microgravity environment. The construction cost is high, and the duration of the microgravity environment is too short. The water flotation method uses the buoyancy of water to offset the gravity of the spacecraft, which can achieve a microgravity environment for any time. The disadvantage is that the experimental equipment needs to be specially waterproofed. The air flotation method uses gas to lift the experimental equipment, which requires precise control of the flow rate of the ejected airflow, and the equipment processing, installation and debugging are more troublesome. The suspension method is to use suspension wires to suspend the experimental equipment and use the tension of the suspension wires to balance gravity. It is a common way to simulate microgravity. The suspension method uses the tension of the suspension wires to balance the gravity on the detector. By accurately calculating the position of the suspension wires, the suspension method can provide accurate gravity unloading to ensure that the optical components and structures of the optical load are not deformed by gravity. The more suspension wires there are, the smaller the stress deformation near the connection point of a single suspension wire, but the more complex the suspension system. The commonly used suspension wire system currently has less than 10 suspension wires. The suspension wire method is a passive support system that does not involve active mechanical components, reduces possible mechanical vibration and interference, has a simple structure, high reliability, and low maintenance costs.

[0006] However, in space gravitational wave detection, precision optical remote sensing and other tasks, it is required that when gravity unloading is performed on a large mass optical payload, the gravity unloading device or mechanism needs to minimize the impact on the high-precision pointing adjustment performance of the large mass optical payload at the micro-radian to nano-radian level. In the above existing gravity unloading methods, when considering gravity unloading, the impact of the gravity unloading device or mechanism on the high-precision pointing adjustment performance is not considered, and it cannot meet the application requirements of ground testing of the precision pointing adjustment performance of large mass optical payloads in space gravitational wave detection, precision optical remote sensing and other tasks. Summary of the invention

[0007] The purpose of the present invention is to provide a one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device to solve the problems mentioned in the background technology.

[0008] To achieve the above-mentioned purpose, the present invention provides a one-dimensional pointing precision adjustable large-mass optical load gravity unloading device that performs gravity unloading through a steel wire rope, comprising a fixed base, a fixed frame is arranged on the fixed base, a one-dimensional precision rotating mechanism is arranged on the fixed frame, the one-dimensional precision rotating mechanism comprises a one-dimensional rotating shaft, the one-dimensional rotating shaft is symmetrically arranged in the fixed frame, and a large-mass optical load is arranged between the two one-dimensional rotating shafts.

[0009] Preferably, a connecting frame is provided on one side of the fixed frame, a precision driver is provided on the connecting frame, and the precision driver is connected to the large-mass optical payload.

[0010] Preferably, the connecting frame is arranged in a "C" shape.

[0011] Preferably, a gravity unloading fixing seat is provided above the fixed frame, and a precision rotating bearing is fixedly sleeved on the top of the gravity unloading fixing seat.

[0012] Preferably, the precision rotating bearing is coaxially arranged with the one-dimensional rotating shaft.

[0013] Preferably, a first steel wire rope and a second steel wire rope are respectively arranged on both sides of the outer wall of the precision rotating bearing, and the bottom ends of the first steel wire rope and the second steel wire rope are both connected to the large-mass optical payload.

[0014] Preferably, both the first steel wire rope and the second steel wire rope are arranged in the plane formed by the axis of the one-dimensional rotating shaft and the optical axis of the large-mass optical payload.

[0015] Preferably, a support cross bar is fixedly connected to the outer wall of the precision rotating bearing, the other end of the support cross bar is connected with a suspension steel wire rope, and the other end of the suspension steel wire rope is connected to the large-mass optical payload.

[0016] Preferably, the arrangement direction of the support cross bar is parallel to the optical axis direction of the large-mass optical payload.

[0017] Preferably, the suspension steel wire rope is located in the vertical line direction of the center of mass of the large-mass optical payload.

[0018] Therefore, by adopting the above one-dimensional pointing precision adjustable large-mass optical payload gravity unloading device, the present invention has the following beneficial effects: while realizing the gravity unloading of the large-mass optical payload, it has no influence on the precision pointing adjustment performance of the large-mass optical payload in the one-dimensional direction, so as to be able to simulate and test the high-precision pointing adjustment performance of the large-mass optical payload on the ground.

[0019] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments. Description of the Drawings

[0020] Figure 1 is the structural schematic diagram of Embodiment 1 of the present invention; Figure 2 is the top view of Embodiment 1 of the present invention; Figure 3 is the side view of Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of angle deflection in the horizontal direction according to Embodiment 1 of the present invention; Figure 5 This is a schematic diagram of the structure of Embodiment 2 of the present invention; Figure 6 is a top view of embodiment 2 of the present invention; Figure 7 It is a side view of embodiment 2 of the present invention; Figure 8 This is a schematic diagram of angle deflection in the horizontal direction according to Embodiment 2 of the present invention; Reference numerals 1. Large mass optical load; 2. One-dimensional precision rotation mechanism; 3. Precision drive; 4. Fixed frame; 5. Fixed base; 6. Gravity unloading fixed seat; 7. Wire rope one; 8. Precision rotating bearing; 9. Wire rope two; 10. Support crossbar; 11. Suspension wire rope; 12. Center of mass; T1 is the tension of wire rope one on the large mass optical load; T2, the tension of wire rope two on the large mass optical load; G, the gravity of the large mass optical load; m, the mass of the large mass optical load; g, gravitational acceleration; α, the angle of deflection of the gravity unloading device in the horizontal direction; T3, the tension of the suspension wire rope on the large mass optical load. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0023] The present invention provides a gravity unloading device for a one-dimensional pointing precision-adjustable large-mass optical payload that performs gravity unloading through a wire rope, including a fixed base 5, a fixed frame 4 is arranged on the fixed base 5, and a one-dimensional precision rotation mechanism is arranged on the fixed frame 4. The one-dimensional precision rotation mechanism 2 includes a one-dimensional rotating shaft, the one-dimensional rotating shafts are symmetrically arranged in the fixed frame 4, and a large-mass optical payload 1 is arranged between the two one-dimensional rotating shafts. The driving point of the precision driver 3 acts on the large-mass optical payload 1, and the precision driver 3 generates a driving force to drive the large-mass optical payload 1, so that the pointing direction of the large-mass optical payload 1 deflects at a high-precision angle around the one-dimensional rotating shaft of the one-dimensional precision rotation mechanism 2.

[0024] A connecting frame is arranged on one side of the fixed frame 4, and the connecting frame is arranged in a "C" shape. The precision driver 3 is arranged on the connecting frame, and the precision driver 3 is connected to the large-mass optical payload 1.

[0025] A gravity unloading fixed seat 6 is arranged above the fixed frame 4, and a precision rotating bearing 8 is fixedly sleeved on the top of the gravity unloading fixed seat 6. The precision rotating bearing 8 is coaxially arranged with the one-dimensional rotating shaft.

[0026] Embodiment 1 As Figure 1-4 shown, a wire rope one 7 and a wire rope two 9 are respectively arranged on both sides of the outer wall of the precision rotating bearing 8, and the bottom ends of the wire rope one 7 and the wire rope two 9 are both connected to the large-mass optical payload 1. The wire rope one 7 and the wire rope two 9 are both arranged in the plane formed by the axis of the one-dimensional rotating shaft and the optical axis of the large-mass optical payload 1. The pulling forces of the wire rope one 7 and the wire rope two 9 on the large-mass optical payload 1 are balanced with the gravity of the large-mass optical payload 1, realizing gravity unloading at the rotating shaft; and, during the process of precisely adjusting the pointing of the large-mass optical payload 1, the wire rope one 7 and the wire rope two 9 rotate synchronously around the axis of the one-dimensional rotating shaft following the change of the pointing of the large-mass optical payload 1, so that while the wire rope one 7 and the wire rope two 9 realize gravity unloading, they have no influence on the precision pointing adjustment performance of the large-mass optical payload 1 in the one-dimensional direction.

[0027] Embodiment 2 As Figure 5-8As shown, the outer wall of the precision rotating bearing 8 is fixedly connected with a supporting crossbar 10, the arrangement direction of the supporting crossbar 10 is parallel to the visual axis direction of the large mass optical load 1, and the other end of the supporting crossbar 10 is connected with a suspension wire rope 11, and the other end of the suspension wire rope 11 is connected to the large mass optical load 1. The suspension wire rope 11 is located in the plumb line direction where the center of mass 12 of the large mass optical load 1 is located. The tension of the suspension wire rope 11 on the large mass optical load 1 is balanced with the gravity of the large mass optical load 1, so as to realize the gravity unloading at the rotating shaft; and in the process of precisely adjusting the direction of the large mass optical load 1, the suspension wire rope 11 and the supporting crossbar 10 rotate synchronously around the one-dimensional rotating shaft axis following the change of the direction of the large mass optical load 1, so that the suspension wire rope 11 and the supporting crossbar 10 have no influence on the precision direction adjustment performance of the large mass optical load 1 in one-dimensional direction while realizing the gravity unloading.

[0028] Therefore, the present invention adopts the above-mentioned one-dimensional pointing precisely adjustable large-mass optical load gravity unloading device, which not only realizes the gravity unloading of the large-mass optical load, but also has no influence on the precise pointing adjustment performance of the large-mass optical load in the one-dimensional direction, thereby realizing the simulation test of the high-precision pointing adjustment performance of the large-mass optical load on the ground.

[0029] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A one-dimensionally pointing, precisely adjustable, large-mass optical load gravity unloading device, characterized in that: Gravity unloading is carried out through a wire rope, including a fixed base, on which a fixed frame is provided. A one-dimensional precision rotation mechanism is provided on the fixed frame. The one-dimensional precision rotation mechanism includes a one-dimensional rotating shaft, which is symmetrically arranged in the fixed frame. A large-mass optical payload is arranged between the two one-dimensional rotating shafts.

2. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 1 is characterized by: A connecting frame is provided on one side of the fixed frame. A precision driver is provided on the connecting frame, and the precision driver is connected to the large-mass optical payload.

3. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 2 is characterized by: The connecting frame is arranged in a "C" shape.

4. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 3 is characterized by: A gravity unloading fixed seat is provided above the fixed frame. A precision rotating bearing is fixedly sleeved on the top of the gravity unloading fixed seat.

5. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 4 is characterized in that: The precision rotating bearing is coaxially arranged with the one-dimensional rotating shaft.

6. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 5 is characterized by: On both sides of the outer wall of the precision rotating bearing, a wire rope one and a wire rope two are respectively provided. The bottom ends of the wire rope one and the wire rope two are both connected to the large-mass optical payload.

7. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 6, characterized in that: Both the wire rope one and the wire rope two are arranged in the plane formed by the axis of the one-dimensional rotating shaft and the optical axis of the large-mass optical payload.

8. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 5, characterized in that: A support cross bar is fixedly connected to the outer wall of the precision rotating bearing. The other end of the support cross bar is connected to a suspension wire rope, and the other end of the suspension wire rope is connected to the large-mass optical payload.

9. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 8, characterized in that: The arrangement direction of the support cross bar is parallel to the optical axis direction of the large-mass optical payload.

10. The one-dimensionally pointing precisely adjustable large-mass optical load gravity unloading device according to claim 9, characterized in that: The suspension wire rope is located in the vertical line direction of the center of mass of the large-mass optical payload.

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