CN108169872B - A high precision and high stability mirror adjustment device based on flexible hinge - Google Patents

Abstract

The invention discloses a high-precision and high-stability mirror adjustment device based on a flexible hinge, comprising at least three flexible support mechanisms, and the flexible support mechanisms have the same structure, including a motor, a flexible hinge, a differential thread reducer and a displacement sensor. At both ends of the shaft, the motor is fixedly connected to the flexible hinge at the connection with the shell of the differential thread reducer, and the shells of the differential thread reducer can slide relative to each other. The shape of the flexible hinge is an octagonal structure with four faces in the orthogonal direction. It is a non-deformable mounting surface, and the other four surfaces of the flexible hinge are deformable thin-plate structures; the motor drives the differential thread reducer housing to move axially, and then drives the flexible hinge deformable thin plate to change the angle to realize the non-deformable mounting surface of the flexible hinge. The radial movement, through the three-dimensional adjustment between the flexible support mechanisms, realizes the adjustment of the mirror installed on the non-deformable installation surface.

Description

A high precision and high stability mirror adjustment device based on flexible hinge

technical field

The invention relates to a high-precision and high-stability reflecting mirror adjustment device based on a flexible hinge, which belongs to the field of precision machinery and can be used in the adjustment links of space optical remote sensing cameras and ground precision instruments requiring high precision and high stability.

Background technique

In most cases, during the ground installation of space optical instruments, the mirror assembly is adjusted in place with the help of a universal multi-dimensional adjustment platform or an industrial manipulator, and the reflection mirror assembly is adjusted by grinding the spacer between the mirror assembly and the structural body of the optical instrument. The mirror assembly is effectively secured, then the universal adjustment mechanism is removed. The advantage of this solution is that it is simple to implement, but the disadvantage is that residual positional deviation will occur during the component fixing process. In addition, this method is a one-time adjustment and cannot be corrected on-orbit;

Some domestic research institutes use the Hexapod-type platform mechanism as the mirror adjustment mechanism. This mechanism is somewhat flexible in the adjustment freedom and high precision. There is a strong coupling between them, the control process is complicated, the mechanism is large in size and weight, and the mechanical environment resistance is poor. There is no practical example of on-orbit application.

SUMMARY OF THE INVENTION

The technical problem solved by the present invention is: in order to overcome the deficiencies of the prior art, a high-precision and high-stability mirror adjustment device based on a flexible hinge is provided to realize three degrees of freedom adjustment of the mirror assembly on the rail and on the ground.

The technical solution of the present invention is:

A high-precision, high-stability mirror adjustment device based on a flexible hinge, comprising at least three flexible support mechanisms, the flexible support mechanisms have the same structure, including a motor, a flexible hinge, a differential thread reducer and a displacement sensor, and the motor is placed on two sides of the shaft. At the end, the motor is fixedly connected with the flexible hinge at the connection with the housing of the differential thread reducer, and the housings of the differential thread reducer can slide relative to each other.

The shape of the flexible hinge is an octagonal structure, the four faces in the orthogonal direction are non-deformable mounting faces, and the other four faces of the flexible hinge are deformable sheet structures;

The motor drives the differential thread reducer housing to move axially, and then drives the flexible hinge deformable sheet to change the angle, so as to realize the radial movement of the non-deformable mounting surface of the flexible hinge. adjustment of the reflector.

Two of the four non-deformable mounting surfaces in the orthogonal direction are fixedly connected with the motor and the differential thread reducer shell respectively, and the other two opposite surfaces are connected with the displacement measurement surface. Sensing changes in radial displacement of flexible hinges.

The differential thread reducer is dual redundant and coaxially fixed.

Two reverse threads are arranged on the shaft. The rotation of the motor drives the shaft of the differential thread reducer to rotate, and the steering member of the differential thread reducer drives the differential thread reducer housing to move axially.

The two-dimensional rotation is realized by the combination of one-dimensional movements in the radial direction of each flexible support mechanism, and the three-dimensional adjustment of the mirror is realized by one-dimensional movement along the axial direction of the mirror under the condition of consistent radial movement.

The thickness of the deformable sheet is 1-2mm.

There are three flexible support mechanisms, and the three are distributed at an angle of 120°.

The advantages of the present invention compared with the prior art are:

(1) The present invention not only ensures the release of the degree of freedom in the adjustment direction, but also ensures a small driving torque requirement, and ensures that the mirror can be adjusted without gaps through three points of flexible hinge design in different directions; The distribution of angles ensures the realization of the overall support stiffness of the adjusted reflector, and ensures that the overall structure can withstand the harsh launch mechanics environment of space loads;

(2) The present invention adopts three-position one-dimensional straight line adjustment, which satisfies the two-dimensional rotation of the entire assembly around the X axis and the Y axis and the one-dimensional translation adjustment along the Z axis. The adjustment control process and structural design are simple, and the engineering is realized. It is easy and fully meets the adjustment requirements of the optical system on-orbit;

(3) The single set of flexible support mechanism of the present invention realizes the mutual backup design of two sets of mechanisms through the parallel design of two-way motors, greatly improves the reliability of the mechanism, and meets the high reliability requirements of space optical instruments.

Description of drawings

Fig. 1 is the structure diagram of the flexible support mechanism of the present invention;

FIG. 2 is a sectional view of the structure of the flexible support mechanism of the present invention;

3 is a structural diagram of a mirror adjustment device of the present invention;

FIG. 4 is a schematic diagram of the adjustment of the mirror adjustment device of the present invention.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings.

A high-precision and high-stability mirror adjustment device based on a flexible hinge includes at least three flexible support mechanisms, preferably three flexible support mechanisms, and the three are distributed at an angle of 120°, as shown in FIG. 3 .

The flexible support mechanism has the same structure, including motor 1, flexible hinge 2, differential thread reducer 3 and displacement sensor 4. As shown in Figure 1 and Figure 2, each end of the shaft is coaxially connected to a motor 1, and the motor 1 is connected to The connection between the shells of the differential thread reducer 3 is fixedly connected with the flexible hinge 2, and the shells of the differential thread reducer 3 can slide relative to each other.

The shape of the flexible hinge 2 is an octagonal structure, and the four surfaces in the orthogonal direction are non-deformable installation surfaces. Two of the opposite surfaces are respectively connected to the motor 1 and the differential thread reducer 3. The shell connection is fixedly connected, and the other two opposite surfaces are connected to each other. There is a displacement measurement surface, the displacement sensor 4 senses the change of the radial displacement of the flexible hinge 2 through the contact with the displacement measurement surface, and the other four surfaces of the flexible hinge 2 are deformable thin plate structures;

The differential thread reducer 3 is dual redundant and coaxially fixedly connected. Two reverse threads are provided on the shaft. The rotation of the motor drives the shaft of the differential thread reducer 3 to rotate, and is driven by the steering member of the differential thread reducer 3. The casing of the differential thread reducer 3 moves axially, which in turn drives the flexible hinge 2 deformable sheet to change the angle, so as to realize the radial movement of the non-deformable mounting surface of the flexible hinge 2. High-precision adjustment of mirrors on the face.

The two-dimensional rotation is realized by the combination of one-dimensional movements in the radial direction of each flexible support mechanism, and the three-dimensional adjustment of the mirror is realized by one-dimensional movement along the axial direction of the mirror under the condition of consistent radial movement.

The thickness of the deformable sheet is 1-2 mm, and the thickness of the deformable sheet is calculated according to the load-bearing and stiffness requirements of the structure, and is preferably 1.5 mm thick.

For the mirror that needs to be adjusted, as shown in Figure 4, an adjustment mechanism that can be adjusted in the Z direction is set at each of the three installation points A, B, and C. The three-degree-of-freedom adjustment of the optical element's rotation around X, rotation around Y and translation along the Z axis is exactly the same for the three high-precision adjustment mechanisms.

The working principle of the present invention is as follows: the mirror assembly to be adjusted is mounted on the optical lens body through a flexible hinge mechanism, and when adjustment is required, the control circuit sends an instruction to drive the motor in the control motor to rotate according to the required displacement, and the motor drives the motor in the motor to rotate. The differential thread mechanism converts the rotation of the motor into an axial linear motion, thereby pushing the left and right surfaces of the flexible hinge to move relative to each other, resulting in the deformation of the hinge, resulting in the relative motion between the mounting surface of the adjusted mirror and the mounting surface of the lens body. Finally, the adjustment of the driven load is realized.

The invention solves the problem of high-precision on-orbit adjustment of the reflector assembly of a high-resolution space optical remote sensing camera. The mechanism releases the degrees of freedom in different directions through three points, and solves the gap-free and high-stability on-orbit adjustment of the reflector. At the same time, through reasonable distribution of degrees of freedom, the overall support rigidity of the mirror assembly is ensured. Thereby making the mechanism resistant to mechanical environmental characteristics. In addition, the mechanism has a mechanical self-locking function by using a differential thread deceleration mechanism, and at the same time utilizes a simple and compact structure to achieve a large transmission ratio, thereby improving the accuracy of the adjustment mechanism. It provides an effective means to solve the minor changes and adjustments of the optical system after the space optical precision instrument enters orbit.

The content not described in detail in the specification of the present invention belongs to the well-known technology of those skilled in the art.

Claims (7)

1. A high-precision, high-stability mirror adjustment device based on a flexible hinge, characterized in that: it comprises at least three flexible support mechanisms, and the flexible support mechanisms have the same structure, including a motor (1), a flexible hinge (2), a differential thread The reducer (3) and the displacement sensor (4), the motor (1) is placed at both ends of the shaft, the motor (1) is fixedly connected with the flexible hinge (2) at the connection with the shell of the differential threaded reducer (3), the differential The shells of the threaded reducer (3) can slide relative to each other, The shape of the flexible hinge (2) is an octagonal structure, the four surfaces in the orthogonal direction are non-deformable mounting surfaces, and the other four surfaces of the flexible hinge (2) are deformable thin plate structures; The motor drives the casing of the differential thread reducer (3) to move axially, which in turn drives the flexible hinge (2) deformable sheet to change the angle, so as to realize the radial movement of the non-deformable mounting surface of the flexible hinge (2), through the three-dimensional adjustment between the flexible support mechanisms , to realize the adjustment of the mirror mounted on the non-deformable mounting surface. 2. A high-precision, high-stability mirror adjustment device based on a flexible hinge according to claim 1, characterized in that: two opposite surfaces of the four non-deformable mounting surfaces in the orthogonal direction are respectively connected to the motor (1 ) and the differential thread reducer (3) are fixedly connected at the housing connection, and the other two opposite surfaces are connected with displacement measurement surfaces, and the displacement sensor (4) senses the change in radial displacement of the flexible hinge (2) through contact with the displacement measurement surfaces. 3. A high-precision and high-stability mirror adjustment device based on a flexible hinge as claimed in claim 1, characterized in that the differential thread reducer (3) is dual redundant and coaxially fixedly connected. 4. A high-precision, high-stability mirror adjustment device based on a flexible hinge as claimed in claim 3, characterized in that: two reverse threads are arranged on the shaft, and the rotation of the motor drives the differential thread reducer (3 ) shaft rotates to drive the differential thread reducer (3) casing to move axially through the steering member of the differential thread reducer (3). 5. A high-precision, high-stability mirror adjustment device based on a flexible hinge as claimed in claim 1, characterized in that: two-dimensional rotation is realized by a combination of one-dimensional movements along the radial direction of each flexible support mechanism, and In the case of consistent radial movement, one-dimensional movement along the axial direction of the mirror realizes three-dimensional adjustment of the mirror. 6 . The high-precision and high-stability mirror adjustment device based on a flexible hinge according to claim 1 , wherein the thickness of the deformable sheet is 1-2 mm. 7 . 7 . The high-precision and high-stability mirror adjustment device based on a flexible hinge according to claim 1 , wherein: there are three flexible support mechanisms, and the three are distributed at an angle of 120°. 8 .

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