A converging six-degree-of-freedom passive isolation system

Abstract

This invention discloses a convergent six-degree-of-freedom passive vibration isolation system, relating to the field of aerospace technology. It includes an upper support and a lower support; six passive vibration isolators are arranged between the upper and lower supports; each passive vibration isolator includes a cylinder, an upper end plate, a lower end plate, a piston rod, a piston plate, an upper pressure plate, and a lower pressure plate; the upper and lower pressure plates are distributed on the upper and lower sides of the piston plate; the upper pressure plate is connected to the upper end plate by an upper spring, and the lower pressure plate is connected to the lower end plate by a lower spring; an upper rubber ring is sandwiched between the upper pressure plate and the piston plate, and a lower rubber ring is sandwiched between the lower pressure plate and the piston plate. This invention uses the cooperation of rubber rings and springs for micro-vibration isolation, effectively reducing the amplitude during resonance.

Description

Technical Field

[0001] This invention relates to the field of aerospace technology, and in particular to a convergent six-degree-of-freedom passive vibration isolation system. Background Technology

[0002] With the rapid development of aerospace technology, the environmental requirements for imaging stability of satellite platforms by optically sensitive payloads are constantly increasing. When spacecraft are operating in orbit, functional components such as reaction wheels, control moment gyroscopes, and antenna drive mechanisms experience a series of small-amplitude, wide-bandwidth micro-vibrations. These vibrations can cause image blurring, significantly affecting image quality. Therefore, micro-vibration isolation and testing technologies have gradually become crucial for ensuring high-quality imaging.

[0003] Reaction wheels are commonly used attitude control devices in modern high-resolution optical satellites. Due to factors such as rotor dynamic and static imbalance, reaction wheels generate complex harmonic disturbances and noise during operation, leading to decreased imaging stability of the optical payload. This makes the reaction wheel the primary source of disturbance. To reduce the impact of micro-vibrations on the satellite, vibration isolation of the reaction wheel is necessary. Passive vibration isolation technology offers advantages such as high reliability and no need for external power, making it suitable for the complex space environment. D. Kamesh et al. proposed a vibration isolation platform technology based on a folded beam structure, conducted corresponding theoretical analysis and research, and verified the effectiveness of this scheme in isolating the reaction wheel. Pendergast et al. designed a six-legged vibration isolation platform for each reaction wheel on the Chandra telescope, consisting of vibration isolation units composed of elastic materials and mechanical springs. Test results showed that the vibration isolation platform had a good vibration reduction effect. Zhou et al. designed a folded beam passive vibration isolation system, established a dynamic model of the reaction wheel and the isolation system, and effectively suppressed high-frequency disturbances; however, disturbance amplification occurred in some operating conditions. While the above vibration isolation schemes offer good vibration isolation performance, they primarily rely on the low stiffness of the isolation system to reduce the disturbance of the reaction wheel under high-speed rotation. Isolation based solely on low stiffness cannot effectively reduce the amplitude at resonance. Summary of the Invention

[0004] The main objective of this invention is to provide a convergent six-degree-of-freedom passive vibration isolation system to solve the above-mentioned problems.

[0005] To achieve the above objectives, the present invention provides a convergent six-degree-of-freedom passive vibration isolation system, comprising an upper support for connection to a reaction wheel and a lower support for connection to a satellite body; six passive vibration isolators are arranged between the upper and lower supports; the six passive vibration isolators are divided into three groups, each group consisting of two passive vibration isolators arranged in a figure-eight pattern, and the three groups of passive vibration isolators are evenly distributed on the circumference, wherein the circumference diameter of the end of the passive vibration isolator connected to the upper support is smaller than the circumference diameter of the end of the passive vibration isolator connected to the lower support;

[0006] The passive vibration isolator includes a cylinder with an upper end plate at its upper end. A through hole is provided in the middle of the upper end plate, and a piston rod is slidably disposed within the through hole. A piston plate is slidably disposed in the middle of the cylinder. The upper end of the piston rod is universally hinged to an upper support, and the lower end is connected to the piston plate. A lower end plate is provided at the lower end of the cylinder, and a support rod is provided at the lower part of the lower end plate. The lower end of the support rod is universally hinged to a lower support. An upper pressure plate and a lower pressure plate are also slidably disposed within the cylinder. The upper and lower pressure plates are distributed on the upper and lower sides of the piston plate. The upper pressure plate is connected to the upper end plate via an upper spring, and the lower pressure plate is connected to the lower end plate via a lower spring. An upper rubber ring is sandwiched between the upper pressure plate and the piston plate, and a lower rubber ring is sandwiched between the lower pressure plate and the piston plate.

[0007] Furthermore, the upper and lower pressure plates are provided with annular relief grooves on the side facing the piston plate, and an annular plate is slidably disposed in the annular relief groove. The annular plate is connected to the bottom of the annular relief groove by multiple fine-tuning springs.

[0008] Furthermore, both the upper and lower springs are manganese-copper high-damping alloy springs.

[0009] Furthermore, the hinge points of the six passive vibration isolators and the lower support are evenly distributed on the lower support.

[0010] Furthermore, a passive vibration isolator is universally hinged between the centers of the upper and lower supports.

[0011] The present invention has the following beneficial effects:

[0012] This invention uses a combination of rubber rings and springs for micro-vibration isolation, effectively reducing the amplitude during resonance. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a convergent six-degree-of-freedom passive vibration isolation system according to the present invention.

[0014] Figure 2 This is a schematic diagram of a passive vibration isolator in a convergent six-degree-of-freedom passive vibration isolation system according to the present invention.

[0015] Among them, 1-reaction wheel; 2-upper bracket; 3-passive vibration isolator; 4-lower bracket; 31-piston rod; 32-upper end plate; 33-upper spring; 34-cylinder; 35-upper pressure plate; 36-upper rubber ring; 37-piston plate; 38-lower rubber ring; 39-lower pressure plate; 40-lower spring; 41-lower end plate; 391-annular relief groove; 392-fine adjustment spring; 393-annular plate. Detailed Implementation

[0016] To achieve the above objectives and effects, the technical means and structure adopted by the present invention will be described in detail with reference to the accompanying drawings, focusing on the features and functions of the preferred embodiments of the present invention.

[0017] like Figure 1-2 As shown, this invention provides a convergent six-degree-of-freedom passive vibration isolation system, including an upper support 2 for connecting to a reaction wheel 1 and a lower support 4 for connecting to the satellite body; six passive vibration isolators 3 are arranged between the upper support 2 and the lower support 4; the six passive vibration isolators 3 are divided into three groups, each group consisting of two passive vibration isolators 3 arranged in a figure-eight pattern, and the three groups of passive vibration isolators 3 are evenly distributed on the circumference. The circumference diameter of the end of the passive vibration isolator 3 connected to the upper support 2 is smaller than the circumference diameter of the end of the passive vibration isolator 3 connected to the lower support 4, so that the six passive vibration isolators 3 tilt inward and converge to form a six-degree-of-freedom structure;

[0018] The passive vibration isolator 3 includes a cylinder 34, with an upper end plate 32 at the upper end of the cylinder 34. A through hole is provided in the middle of the upper end plate 32, and a piston rod 31 is slidably disposed within the through hole. A piston plate 37 is slidably disposed in the middle of the cylinder 34. The upper end of the piston rod 31 is universally hinged to the upper bracket 2, and the lower end is connected to the piston plate 37. A lower end plate 41 is provided at the lower end of the cylinder 34, and a support rod 42 is provided at the lower part of the lower end plate 41. The lower end of the support rod 42 is connected to the lower bracket. 4. Universal hinge; an upper pressure plate 35 and a lower pressure plate 39 are also slidably disposed inside the cylinder 34; the upper pressure plate 35 and the lower pressure plate 39 are distributed on the upper and lower sides of the piston plate 37; the upper pressure plate 35 is connected to the upper end plate 32 by an upper spring 33, and the lower pressure plate 39 is connected to the lower end plate 41 by a lower spring 40; an upper rubber ring 36 is sandwiched between the upper pressure plate 35 and the piston plate 37, and a lower rubber ring 38 is sandwiched between the lower pressure plate 39 and the piston plate 37.

[0019] The vibration generated by the reaction wheel 1 during operation is transmitted to the upper support 2. Under vibration, the upper support 2 stretches or compresses the piston rod 31 of the passive vibration isolator 3. The piston rod 31 drives the piston plate 37 to move within the cylinder 34, thereby compressing the upper rubber ring 36 or the lower rubber ring 38. The upper rubber ring 36 or the lower rubber ring 38 deforms, thus providing the elastic restoring force and damping force required for micro-vibration isolation. Under large-amplitude vibration, the upper spring 33 or the lower spring 40 is further compressed, causing deformation. Together with the upper rubber ring 36 or the lower rubber ring 38, the upper spring 33 or the lower spring 40 provides the elastic restoring force and damping force required for large-amplitude vibration isolation.

[0020] In another embodiment, both the upper pressure plate 35 and the lower pressure plate 39 are provided with annular relief grooves 391 on the side facing the piston plate 37. An annular plate 393 is slidably disposed within the annular relief groove 391, and the annular plate 393 is connected to the bottom of the annular relief groove 391 by a plurality of fine-tuning springs 392. When the upper rubber ring 36 or the lower rubber ring 38 deforms, the upper rubber ring 36 or the lower rubber ring 38 will compress the annular plate 393 and push it into the annular relief groove 391, so that the upper rubber ring 36 or the lower rubber ring 38 and the fine-tuning springs 392 move in coordination, further eliminating micro-vibrations.

[0021] In another embodiment, both the upper spring 33 and the lower spring 10 are manganese copper high-damping alloy springs. Manganese copper high-damping alloy has the characteristics of high damping on the basis of the advantages of traditional metal materials. When subjected to vibration from a vibration source, it can drive the twin cross section inside the material to produce sliding motion, convert mechanical energy into heat energy, cut off the vibration propagation path, and efficiently suppress micro-vibrations.

[0022] In another embodiment, the hinge points of the six passive vibration isolators 3 and the lower support 4 are evenly distributed on the circumference of the lower support 4, so that the lower support 4 is subjected to uniform force.

[0023] In another embodiment, a passive vibration isolator 3 is universally hinged between the center of the upper support 2 and the lower support 4, thereby forming a reaction force with the other six passive vibration isolators 3, so that all the passive vibration isolators 3 are under stress, the upper support is in a state of force balance, and no large vibration will be generated when the reaction wheel 1 starts or stops.

[0024] The above description is only a preferred embodiment of the present invention and not all embodiments. Anyone should know that structural changes made under the guidance of the present invention, and any technical solutions that are the same as or similar to the present invention, are within the protection scope of the present invention.

Claims

1. A convergent six-degree-of-freedom passive vibration isolation system, characterized in that, It includes an upper support for connecting to the reaction wheel and a lower support for connecting to the satellite body; six passive vibration isolators are provided between the upper support and the lower support; the six passive vibration isolators are divided into three groups, each group consisting of two passive vibration isolators arranged in a figure-eight shape, and the three groups of passive vibration isolators are evenly distributed on the circumference, and the circumference diameter of the end of the passive vibration isolator connected to the upper support is smaller than the circumference diameter of the end of the passive vibration isolator connected to the lower support; The passive vibration isolator includes a cylinder with an upper end plate at its upper end. A through hole is provided in the middle of the upper end plate, and a piston rod is slidably disposed within the through hole. A piston plate is slidably disposed in the middle of the cylinder. The upper end of the piston rod is universally hinged to an upper support, and the lower end is connected to the piston plate. A lower end plate is provided at the lower end of the cylinder, and a support rod is provided at the lower part of the lower end plate. The lower end of the support rod is universally hinged to a lower support. An upper pressure plate and a lower pressure plate are also slidably disposed within the cylinder. The upper and lower pressure plates are distributed on the upper and lower sides of the piston plate. The upper pressure plate is connected to the upper end plate via an upper spring, and the lower pressure plate is connected to the lower end plate via a lower spring. An upper rubber ring is sandwiched between the upper pressure plate and the piston plate, and a lower rubber ring is sandwiched between the lower pressure plate and the piston plate. The upper and lower pressure plates are provided with annular relief grooves on the side facing the piston plate. An annular plate is slidably disposed in the annular relief groove, and the annular plate is connected to the bottom of the annular relief groove by multiple fine-tuning springs.

2. The convergent six-degree-of-freedom passive vibration isolation system as described in claim 1, characterized in that, Both the upper and lower springs are manganese-copper high-damping alloy springs.

3. A convergent six-degree-of-freedom passive vibration isolation system as described in claim 1 or 2, characterized in that, The hinge points of the six passive vibration isolators and the lower support are evenly distributed on the lower support.

4. The convergent six-degree-of-freedom passive vibration isolation system as described in claim 3, characterized in that, A passive vibration isolator is also universally hinged between the centers of the upper and lower supports.

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