Three-axis rotating device and rocket sled test system

Abstract

The invention discloses a three-axis rotating device and a rocket sled testing system, and relates to the technical field of rocket sled. The three-axis rotating device comprises a pair of yaw rotating limiting blocks used for being connected with a rocket sled, a pair of yaw rotating fan-shaped blocks, a pitching rotating ring and a plurality of transverse rolling rotating supports used for being connected with test pieces, and the two yaw rotating fan-shaped blocks are connected to the two yaw rotating limiting blocks in the mode that the two yaw rotating fan-shaped blocks can rotate along the horizontal plane respectively. The two ends of the pitching rotating ring can be connected to the two yaw rotating fan-shaped blocks in the mode of rotating along the horizontal axis, and the rolling rotating support can be connected to the pitching rotating ring in the mode of rotating around the axis of the pitching rotating ring. According to the three-axis rotating device and the rocket sled test system provided by the invention, the test piece can be stably fixed on the rocket sled to realize a test under three axial rotation degrees of freedom, and the problem that an existing rocket sled cannot perform a cylindrical projectile body test piece attitude control system-level test is solved.

Description

Technical Field

[0001] The present application relates to the field of rocket sled technology, and in particular to a three-axis rotating device and a rocket sled test system. Background Art

[0002] The rocket sled test device is a device that uses a rocket engine as power and uses a sled as a test platform to carry test pieces and test equipment and slide at high speed along a special slide rail to simulate the dynamic working conditions of the test piece in working sections such as startup, air flight, and function realization. It is a comprehensive large-scale dynamic test device that obtains the performance parameters of the test piece through a test system and conducts performance verification, identification, evaluation, and failure mode analysis of the test piece based on this.

[0003] In order to verify the attitude control system of a relatively slender body structure test piece in flight, it is necessary to realize the three-axis rotation function of the test piece during the operation of the rocket sled. At the same time, the mass and moment of inertia of the three-axis rotation device attached to the test piece should be as small as possible, while also being able to transmit various loads during the test, including acceleration, braking, aerodynamics and attitude control.

[0004] However, the current rocket sled test process is limited by the structure of the rocket sled body installed on the ground track. At the same time, in order to reduce the aerodynamic drag and torque during high-speed testing, the test piece is generally installed on the rocket sled body with a fixed attitude angle and as close to the track surface as possible. As a result, the test piece can only achieve a single-axis roll along the heading axis at most, and cannot achieve three-axis rotation of the test piece at the same time. Therefore, it is impossible to simulate the system-level verification test including the control system in a free state. Summary of the invention

[0005] The purpose of the present application is to provide a three-axis rotation device and a rocket sled test system, which can stably fix the test piece on the rocket sled to realize the test under three-axis rotational degrees of freedom, thereby solving the problem that the existing rocket sled cannot perform test of the test piece attitude control system level.

[0006] This application is implemented as follows:

[0007] The present application provides a three-axis rotation device, which includes a pair of yaw rotation limit blocks for connecting a rocket sled, a pair of yaw rotation sector blocks, a pitch rotation ring and a plurality of roll rotation brackets for connecting a test piece, wherein the two yaw rotation sector blocks can be rotatably connected to the two yaw rotation limit blocks along a horizontal plane, the two ends of the pitch rotation ring can be rotatably connected to the two yaw rotation sector blocks along a horizontal axis, and the roll rotation bracket can be rotatably connected to the pitch rotation ring around the axis of the pitch rotation ring.

[0008] In some optional embodiments, a waist-shaped hole is provided on the yaw rotating sector block, and the yaw rotating limit block is connected to a central axis passing through the corresponding waist-shaped hole. When the yaw rotating sector block rotates along the horizontal plane, the central axis moves along the waist-shaped hole, and the two ends of the pitch rotating ring are respectively connected to the two yaw rotating limit blocks through a pitch rotating shaft and can be rotatably connected along the horizontal axis.

[0009] In some optional embodiments, at least one first arc-shaped boss is provided on the top and / or bottom of the yaw rotating sector block, and the yaw rotating limit block is connected to at least one first limit ball bearing, so that when the yaw rotating sector block rotates along the horizontal plane, the first limit ball bearing rolls and presses against the first arc-shaped boss.

[0010] In some optional embodiments, at least one second arc-shaped boss is provided on the side of the yaw rotation sector block, and the yaw rotation limit block is connected to at least one second limit ball bearing that rolls and presses against the second arc-shaped boss, and the second limit ball bearing is used to limit the outward movement of the yaw rotation sector block.

[0011] In some optional embodiments, at least one third limiting ball bearing is provided on the central shaft for rolling and pressing against the inner wall of the waist-shaped hole, and the third limiting ball bearing is used for limiting the inward movement of the yaw rotating sector block.

[0012] In some optional implementation schemes, the yaw rotation limit block is connected to at least one supporting seat by bolts, an adjusting gasket is provided between the supporting seat and the yaw rotation limit block, and the third limiting ball bearing is provided on the supporting seat.

[0013] In some optional embodiments, each pitch axis is rotatably connected to the corresponding yaw rotation limit block via at least two axis ball bearings with different diameters, and / or, at least one side outer wall of the pitch rotation ring is provided with a plurality of load-reducing grooves arranged at intervals along its circumference.

[0014] In some optional embodiments, the inner wall of the pitch rotating ring is provided with at least two convex rings extending along its circumference, and the roll rotating bracket is connected with at least two radial limiting ball bearings that roll and press against the convex rings.

[0015] In some optional embodiments, the inner wall of the pitch rotating ring is provided with at least one limiting groove extending along its circumference, and the roll rotating bracket is connected with at least one axial limiting ball bearing, and the axial limiting ball bearings respectively roll against the side walls of the limiting groove.

[0016] The present application also provides a rocket sled test system, comprising the above-mentioned three-axis rotation device and a rocket sled, wherein two yaw rotation limit blocks of the three-axis rotation device are connected to the rocket sled.

[0017] The beneficial effects of the present application are as follows: the three-axis rotation device provided by the present application includes a pair of yaw rotation limit blocks for connecting to a rocket sled, a pair of yaw rotation sector blocks, a pitch rotation ring and a plurality of roll rotation brackets for connecting to a test piece, the two yaw rotation sector blocks can be respectively connected to the two yaw rotation limit blocks rotatably along a horizontal plane, the two ends of the pitch rotation ring can respectively be connected to the two yaw rotation sector blocks rotatably along a horizontal axis, and the roll rotation bracket can be connected to the pitch rotation ring rotatably around the pitch rotation ring axis. The three-axis rotation device and rocket sled test system provided by the present application can stably fix the test piece on the rocket sled to realize the test under three-axis rotational degrees of freedom, solving the problem that the existing rocket sled cannot perform test of the test piece attitude control system level. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A schematic diagram of the structure of a three-axis rotating device provided in an embodiment of the present application;

[0020] Figure 2 A schematic diagram of the structure of a yaw rotation limit block in a three-axis rotation device provided in an embodiment of the present application;

[0021] Figure 3 A schematic diagram of the structure of a yaw rotating sector block in a three-axis rotating device provided in an embodiment of the present application;

[0022] Figure 4 A schematic diagram of the structure of a pitch rotation ring in a three-axis rotation device provided in an embodiment of the present application;

[0023] Figure 5 A schematic diagram of the structure of a rolling rotating bracket in a three-axis rotating device provided in an embodiment of the present application.

[0024] In the figure: 100, yaw rotation limit block; 110, middle axis; 120, first limit ball bearing; 130, second limit ball bearing; 140, third limit ball bearing; 150, support bracket; 160, adjustment gasket; 200, yaw rotation sector block; 210, waist-shaped hole; 220, first arc-shaped boss; 230, second arc-shaped boss; 240, step hole; 250, cover plate; 300, pitch rotation ring; 310, pitch rotation axis; 320, rotation axis ball bearing; 330, load-reducing groove; 340, convex ring; 350, limit groove; 360, reinforcing rib; 400, roll rotation bracket; 410, radial limit ball bearing; 420, axial limit ball bearing; 430, rotary joint; 440, sliding assembly; 450, ear plate. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0027] 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.

[0028] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the application is usually placed when in use. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0029] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0030] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0031] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0032] The features and performances of the three-axis rotating device and rocket sled test system of the present application are further described in detail below in conjunction with the embodiments.

[0033] like Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, an embodiment of the present application provides a three-axis rotation device, which includes a pair of yaw rotation limit blocks 100 for connecting a rocket sled, a pair of yaw rotation sector blocks 200, a pitch rotation ring 300 and six roll rotation brackets 400 for connecting a test piece, the two yaw rotation sector blocks 200 can be rotatably connected to the two yaw rotation limit blocks 100 along a horizontal plane, respectively, the two ends of the pitch rotation ring 300 can be rotatably connected to the two yaw rotation sector blocks 200 along a horizontal axis, respectively, and each roll rotation bracket 400 can be rotatably connected to the inner wall of the pitch rotation ring 300 around the axis of the pitch rotation ring 300.

[0034] Among them, the two yaw rotating sector blocks 200 are respectively provided with waist-shaped holes 210 passing through the top and bottom surfaces thereof, and the two yaw rotating limit blocks 100 are respectively connected with the central axis 110 passing through the waist-shaped holes 210 on the corresponding yaw rotating sector blocks 200. When the yaw rotating sector block 200 rotates along the horizontal plane, the central axis 110 moves along the waist-shaped holes 210; the top and bottom of the yaw rotating sector block 200 are respectively provided with a first arc-shaped boss 220, and the top two ends and the bottom two ends of the yaw rotating limit block 100 are respectively connected with a first limiting ball bearing 120; when the yaw rotating sector block 200 rotates along the horizontal plane, the two first limiting ball bearings 120 at the top of the yaw rotating limit block 100 and the two first limiting ball bearings 120 at the bottom respectively roll and press the top of the yaw rotating sector block 200 The yaw rotation sector block 200 is provided with two second arc-shaped bosses 230 arranged at intervals up and down on the side thereof, and two ends of the yaw rotation limit block 100 are respectively connected to two second limit ball bearings 130 arranged up and down; when the yaw rotation sector block 200 rotates along the horizontal plane, the second limit ball bearings 130 connected to the upper and lower parts of the two ends of the yaw rotation limit block 100 roll and press against the upper and lower second arc-shaped bosses 230 respectively to limit the yaw rotation sector block 200 from moving outward; two third limit ball bearings 140 arranged up and down are provided on the central axis 110, and when the yaw rotation sector block 200 rotates along the horizontal plane, the third limit ball bearings 140 roll and press against the inner wall of the waist-shaped hole 210 to limit the yaw rotation sector block 200 from moving inward. The two ends of the yaw rotation limit block 100 are respectively connected to a support bracket 150 that penetrates the side wall of the yaw rotation limit block 100 through four bolts, an adjustment gasket 160 is provided between the support bracket 150 and the yaw rotation limit block 100, and the two second limiting ball bearings 130 at the two ends of the yaw rotation limit block 100 are respectively provided on the two support brackets 150.

[0035] The two ends of the pitch rotating ring 300 are respectively connected to a pitch rotating shaft 310, and the pitch rotating shafts 310 at the two ends of the pitch rotating ring 300 can be rotatably connected to the two yaw rotating limit blocks 100 along the horizontal axis. Each pitch rotating shaft 310 is connected to two rotating shaft ball bearings 320 with different diameters. The yaw rotating limit block 100 is provided with a step hole 240 that rolls with the two rotating shaft ball bearings 320. The end of the step hole 240 is connected to a cover plate 250 for limiting the position of the rotating shaft ball bearings 320. The outer walls of both sides of the pitch rotating ring 300 are respectively provided with 19 load-reducing grooves 330 arranged at intervals along the circumference thereof. A convex ring 340 extending along the circumference is respectively provided at both ends of the inner wall, a limiting groove 350 extending along the circumference is provided in the middle part of the inner wall of the pitch rotating ring 300, the roll rotating bracket 400 includes a rotating joint 430 and a sliding assembly 440 connected to the rotating joint 430 by bolts, the rotating joint 430 is provided with two ear plates 450 for connecting the test piece, the sliding assembly 440 is connected to two radial limiting ball bearings 410 that roll and press against the two convex rings 340 and an axial limiting ball bearing 420 that rolls and presses against the side walls of both sides of the limiting groove 350, and the axial limiting ball bearing 420 is located between the two radial limiting ball bearings 410.

[0036] When the three-axis rotation device provided in the embodiment of the present application is used, the test piece is respectively fixed to the ear plates 450 on the rotating joints 430 in the six roll rotating brackets 400 by bolts, and then the two yaw rotating limit blocks 100 are respectively connected to the rocket sled by bolts. The rocket sled can be used to drive the three-axis rotation device and the test piece for testing. During the test, the six roll rotating brackets 400 are synchronously rotated around the axis of the pitch rotating ring 300 and drive the test piece to rotate around the axis of the pitch rotating ring 300, and the pitch rotating ring 300 drives the two pitch rotating axes 310 to rotate around the horizontal axis. Finally, the pitch rotating ring 300 is rotated through two The two yaw rotation sector blocks 200 connected to the pitch axis 310 rotate along the horizontal plane relative to the two yaw rotation limit blocks 100, so that during the operation of the rocket sled, the test piece can be rotated around three axes through the three-axis rotation device to realize the test under three-axis rotational degrees of freedom, which solves the problem that the existing rocket sled cannot perform attitude control system-level tests on the test piece. It has a high degree of fit with the projectile structure test piece, and the structural dimensions can be adjusted according to the diameter and load requirements of the test piece. When the three-axis rotation device is made of aluminum alloy material, the moment of inertia attached to the projectile structure test piece with a slenderness ratio exceeding 5 can be made not to exceed 0.5% of the moment of inertia of the test piece itself.

[0037] Among them, the two yaw rotating sector blocks 200 are respectively provided with waist-shaped holes 210 passing through the top and bottom surfaces thereof, and the two yaw rotating limit blocks 100 are respectively connected with the central axis 110 passing through the waist-shaped holes 210 on the corresponding yaw rotating sector blocks 200. When the yaw rotating sector blocks 200 rotate along the horizontal plane, the central axis 110 moves along the waist-shaped holes 210, so that the waist-shaped holes 210 are used to limit the deflection angle of the central axis 110, ensuring that the two yaw rotating limit blocks 100 are stably rotated by a preset angle in the horizontal direction relative to the two yaw rotating limit blocks 100, so as to avoid excessive yaw rotation of the test piece, resulting in interference and collision between the test piece with a large aspect ratio projectile structure and the rocket sled body structure, and at the same time, the top and bottom of the yaw rotating sector block 200 are respectively A first arc-shaped boss 220 is provided, and a first limiting ball bearing 120 is respectively connected to the top and bottom ends of the yaw rotation limit block 100. When the yaw rotation sector block 200 rotates along the horizontal plane, the two first limiting ball bearings 120 at the top and the two first limiting ball bearings 120 at the bottom of the yaw rotation limit block 100 respectively roll and press the first arc-shaped boss 220 at the top and the bottom of the yaw rotation sector block 200. On the one hand, the first limiting ball bearings 120 connected to the top and the bottom of the yaw rotation limit block 100 can be used to press and limit the position of the yaw rotation sector block 200, and on the other hand, the first limiting ball bearings 120 and the first arc-shaped boss 220 can cooperate to achieve stable rotation of the yaw rotation sector block 200.

[0038] The side of the yaw rotation sector block 200 is provided with two second arc-shaped bosses 230 arranged at intervals in the upper and lower parts. The two ends of the yaw rotation limit block 100 are respectively connected to two second limit ball bearings 130 arranged in the upper and lower parts. The second limit ball bearings 130 can be used to roll and press the second arc-shaped bosses 230 respectively to limit the yaw rotation sector block 200 from moving outward; two third limit ball bearings 140 arranged in the upper and lower parts are provided on the central axis 110. When the yaw rotation sector block 200 rotates along the horizontal plane, the third limit ball bearings 140 roll and press the inner wall of the waist-shaped hole 210 to limit the yaw rotation sector block 200 from moving inward. Both ends of the yaw rotation limit block 100 are connected to a support bracket 150 that penetrates the side wall of the yaw rotation limit block 100 through four bolts, and an adjusting gasket 160 is provided between the support bracket 150 and the yaw rotation limit block 100. The two second limiting ball bearings 130 at both ends of the yaw rotation limit block 100 are respectively provided on the two support brackets 150. The contact clearance requirement between the yaw rotation limit block 100 and the second arc-shaped boss 230 on the yaw rotation sector block 200 can be adjusted by replacing the adjusting gasket 160, which not only limits the lateral displacement of the yaw rotation sector block 200 but also ensures the flexible rotation of the yaw rotation sector block 200.

[0039] The inner wall of the pitch rotating ring 300 is provided with two convex rings 340 extending along its circumference and a limiting groove 350 extending along its circumference. The sliding assembly 440 of the roll rotating bracket 400 is connected to two radial limiting ball bearings 410 that roll and press against the two convex rings 340 to provide radial constraints on the roll rotation of the roll rotating bracket 400. The sliding assembly 440 of the roll rotating bracket 400 is connected to an axial limiting ball bearing 420 that rolls and presses against the side walls of the limiting groove 350 to withstand the heading load during the operation of the rocket sled while reducing the influence of friction. The two convex rings 340 and the limiting groove 350 on the inner wall of the pitch rotating ring 300 are arranged in a "J" shape. In the "J"-shaped outer wall, reinforcing ribs 360 can be designed in the limiting groove 350 according to strength requirements to meet the axial and radial limiting requirements, and can also meet the load-bearing requirements during the dynamic test of the rocket sled.

[0040] Nineteen load-reducing grooves 330 are arranged at intervals along the circumference of the pitch rotating ring 300 on the outer walls on both sides to reduce the pitch rotating ring 300. Each pitch rotating shaft 310 is connected to two rotating shaft ball bearings 320 with different diameters to realize the rotation around the pitch rotating shaft 310. The yaw rotating limit block 100 is provided with a step hole 240 that rolls with the two rotating shaft ball bearings 320 to improve the installation accuracy of the pitch rotating shaft 310; the end of the step hole 240 is connected to a cover plate 250 for limiting the position of the rotating shaft ball bearing 320 to prevent the rotating shaft ball bearing 320 from falling out. The rotating joint 430 and the sliding assembly 440 of the roll rotating bracket 400 can be connected by bolts to achieve radial fine-tuning to ensure installation accuracy.

[0041] In the embodiment of the present application, the fan angle of the waist-shaped hole 210 is 20 degrees. In other optional embodiments, the fan angle of the waist-shaped hole 210 can be set according to the situation to achieve limit adjustment of the set yaw angle.

[0042] In other optional embodiments, the number of the rolling and rotating brackets 400 for connecting the test piece may also be three, four, five or more than six.

[0043] In other optional embodiments, the number of the first arc-shaped bosses 220 may be two or more.

[0044] In other optional embodiments, the number of the first limiting ball bearings 120 may also be two, three or more than four.

[0045] In other optional embodiments, the number of the second arc-shaped bosses 230 may be one, two, or more than two.

[0046] In other optional embodiments, the number of the second limiting ball bearings 130 may also be one, two, or more than two.

[0047] In other optional embodiments, the number of the third limiting ball bearings 140 may also be one, two, or more than two.

[0048] In other optional embodiments, the number of the rotating shaft ball bearing 320 can also be one or more.

[0049] The embodiment of the present application also provides a rocket sled test system, which includes the above-mentioned three-axis rotation device and a rocket sled, and the two yaw rotation limit blocks 100 of the three-axis rotation device are connected to the rocket sled by bolts.

[0050] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

Claims

1. A three-axis rotating device, characterized in that: It includes a pair of yaw rotation limit blocks for connecting the rocket sled, a pair of yaw rotation sector blocks, a pitch rotation ring and a plurality of roll rotation brackets for connecting the test piece. The two yaw rotation sector blocks can be rotatably connected to the two yaw rotation limit blocks along the horizontal plane, the two ends of the pitch rotation ring can be rotatably connected to the two yaw rotation sector blocks along the horizontal axis, and the roll rotation bracket can be rotatably connected to the pitch rotation ring around the axis of the pitch rotation ring.

2. The three-axis rotating device according to claim 1, characterized in that: The yaw rotating sector block is provided with a waist-shaped hole, and the yaw rotating limit block is connected with a central axis passing through the corresponding waist-shaped hole. When the yaw rotating sector block rotates along the horizontal plane, the central axis moves along the waist-shaped hole, and the two ends of the pitch rotating ring are respectively connected to the two yaw rotating limit blocks through a pitch rotating shaft and can be rotatably connected along the horizontal axis.

3. The three-axis rotating device according to claim 1, characterized in that: At least one first arc-shaped boss is provided on the top and / or bottom of the yaw rotating sector block, and the yaw rotating limit block is connected to at least one first limit ball bearing, so that the first limit ball bearing rolls and presses against the first arc-shaped boss when the yaw rotating sector block rotates along the horizontal plane.

4. The three-axis rotating device according to claim 1, characterized in that: At least one second arc-shaped boss is provided on the side of the yaw rotation sector block, and the yaw rotation limit block is connected with at least one second limit ball bearing that rolls and presses against the second arc-shaped boss, and the second limit ball bearing is used to limit the yaw rotation sector block from moving outward.

5. The three-axis rotating device according to claim 2, characterized in that: At least one third limiting ball bearing is provided on the central shaft and rolls against the inner wall of the waist-shaped hole. The third limiting ball bearing is used to limit the yaw rotating sector block from moving inward.

6. The three-axis rotating device according to claim 5, characterized in that: The yaw rotation limit block is connected to at least one support seat by bolts, an adjusting gasket is arranged between the support seat and the yaw rotation limit block, and the third limiting ball bearing is arranged on the support seat.

7. The three-axis rotating device according to claim 1, characterized in that: Each of the pitch rotation axes is rotatably connected to the corresponding yaw rotation limit block via at least two rotation axis ball bearings with different diameters, and / or at least one side outer wall of the pitch rotation ring is provided with a plurality of load-reducing grooves spaced apart along its circumference.

8. The three-axis rotating device according to claim 1, characterized in that: The inner wall of the pitch rotating ring is provided with at least two convex rings extending along the circumference thereof, and the roll rotating bracket is connected with at least two radial limiting ball bearings rolling and pressing the convex rings.

9. The three-axis rotating device according to claim 8, characterized in that: The inner wall of the pitch rotating ring is provided with at least one limiting groove extending along its circumference, and the roll rotating bracket is connected with at least one axial limiting ball bearing, and the axial limiting ball bearing rolls and presses against the side walls of the limiting groove respectively.

10. A rocket sled test system, characterized in that: It comprises a three-axis rotating device and a rocket sled as described in any one of claims 1 to 9, wherein the two yaw rotation limit blocks of the three-axis rotating device are connected to the rocket sled.

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