Gravity unloading device for large off-axis three-mirror space camera
Technical Field
The invention relates to the technical field of ground tests of space loads, in particular to a gravity unloading device for a large off-axis three-mirror space camera.
Background
When the cantilever type aerospace structure is used for ground adjustment, the cantilever type aerospace structure is influenced by gravity, so that deformation caused by gravity participates in the adjustment process of the optical element, and when the cantilever type aerospace structure is in a microgravity environment, the camera structure rebounds after adjustment, and the position accuracy of the optical element is influenced. The distance between the reflectors of the off-axis three-lens reflex camera is larger, the error caused by gravity cannot be sufficiently compensated by improving the structural rigidity under the state that the optical axis is horizontal, and in order to improve the adjustment precision of the system, the gravity unloading is carried out on the off-axis three-lens reflex camera so as to overcome the 'sky-ground' inconsistent effect of the camera structure. When gravity unloading is carried out, various unloading schemes are generally available, and the main variable parameters are the distribution mode of the unloading force, the magnitude of the unloading force, the spatial position of the action point of the unloading force and the like. At this time, an unloading device capable of accurately and conveniently coping with different unloading schemes is needed.
The unloading method generally simulates different unloading schemes to determine a scheme with the best simulation effect, and then carries out tool design and unloading on the scheme. However, the unloading point of the designed tool can only be in the plane where the gantry support is located, the tool is limited, the tool is only directly and fixedly connected to the front mirror through the hook by a rope for unloading, the problem that the tension and the gravity are not collinear and the like due to tool errors can be caused, and the unloading precision is further reduced. Only the suspension type unloading is carried out, and the suspension tool can be caused to block light, so that inconvenience is caused. The deficiencies of most prior art/products are mainly:
(1) in the gravity unloading freedom release aspect, the defects are mainly that the freedom release is not complete, the other 5 freedom degrees except the gravity direction can not be released completely, and the compensation amount released in each freedom degree direction is less.
(2) In the aspect of applicability, any point in a limited space cannot be unloaded conveniently and quickly. And the unloading mode is single, and a device for suspending and supporting is not adopted, so that the problems of tool interference and load interference and the like when some points are unloaded can be caused.
Based on the above technical problems, a large off-axis three-lens space camera gravity unloading device with high unloading precision, small size of a fine adjustment assembly, combination of supporting unloading and suspension unloading and good adaptability needs to be developed by technical personnel in the field.
Disclosure of Invention
The invention aims to provide a large off-axis three-lens space camera gravity unloading device which is high in unloading precision, can reduce the volume of a fine adjustment assembly, can combine supporting unloading and suspension unloading and is good in adaptability.
In order to achieve the above purpose, the invention provides the following technical scheme:
the invention discloses a gravity unloading device of a large off-axis three-lens space camera, which comprises:
a base and an end seat arranged horizontally; and
the coarse adjustment mechanism comprises an upper guide rail, a lower guide rail and a sliding rod which penetrates through the upper guide rail and the lower guide rail and is connected with the base, one end, far away from the base, of the sliding rod is connected with the end seat, and the upper guide rail and the lower guide rail can move up and down through the sliding rod;
the coarse adjustment mechanism also comprises a coarse adjustment mechanism position adjustment assembly, and the coarse adjustment mechanism position adjustment assembly is used for adjusting the upper and lower positions of the upper guide rail and the lower guide rail;
the upper part and/or the lower part of the coarse adjustment mechanism is/are provided with a fine adjustment mechanism, the fine adjustment mechanism positioned on the upper part of the coarse adjustment mechanism is configured as an upper fine adjustment mechanism, and the fine adjustment mechanism positioned on the lower part of the coarse adjustment mechanism is configured as a lower fine adjustment mechanism;
the base is used for bearing the coarse adjustment mechanism and the fine adjustment mechanism.
Further, the rough adjusting mechanism further comprises an unloading base; and
a leg connected to the unloading base;
a camera connected to the unloading base through the leg;
a coarse adjustment knob is arranged at one end of the base and used for adjusting the distance from the lower guide rail to the unloading base;
specifically, the rough adjustment mechanism further comprises a length adjusting screw rod, one end of the length adjusting screw rod is connected with the upper guide rail, the other end of the length adjusting screw rod is connected with the lower guide rail, and the length adjusting screw rod is used for adjusting the distance between the upper guide rail and the lower guide rail.
Further, the position adjusting assembly of the coarse adjusting mechanism comprises a motor connected to one end of the unloading base away from the supporting leg;
the worm gear transmission mechanism is connected to the output end of the motor through a coupler;
two ends of the motor are respectively connected with a gear rack mechanism;
the coarse adjustment mechanism position adjustment assembly further comprises:
the fixed pulleys are arranged on the top of the end seat and the bottom of the base; and
and the unloading cable is connected to the gear rack mechanism and matched with the fixed pulley, and can drive the upper guide rail and the lower guide rail to move up and down.
As a preferable technical solution of this embodiment, the upper fine adjustment mechanism includes a suspension unloading device connected to the upper rail; and
a load attachment device having one end connected to the hang off-load device and the other end connected to the camera.
Specifically, the suspension unloading device comprises a suspension upper cylindrical roller assembly and a suspension lower cylindrical roller assembly;
a suspension ball hinge having one end connected to the suspension lower cylindrical roller assembly and the other end connected to the load connection device;
a movable pulley connected to the suspended lower cylindrical roller assembly through a rotating shaft; and
the suspension unloading rope is matched with the movable pulley;
a spherical hinge end cover is fixed outside the suspension spherical hinge through a screw;
the accurate force adjusting device is arranged at one end of the suspension unloading cable;
and the tension sensor is arranged at the other end of the suspension unloading rope.
Further, the suspended lower cylindrical roller assembly includes a base; and
a plurality of cylindrical rollers disposed inside the base;
a holding bracket mounted in the base, the holding bracket to carry the cylindrical roller;
and the retaining and limiting device is arranged at one end of the base through a screw.
As another preferable technical solution of this embodiment, the lower fine adjustment mechanism includes a support unloading device having one end fixed to the camera and the other end connected to the lower rail.
Specifically, the supporting and unloading device comprises a supporting upper cylindrical roller assembly and a supporting lower cylindrical roller assembly;
the limiting device is arranged in the upper cylindrical roller assembly of the support;
the supporting spherical hinge is connected to the upper part of the supporting upper cylindrical roller assembly;
the lower end of the upper cylindrical roller supporting component is fixedly connected with a pressure sensor;
and the accurate force adjusting nut penetrates through the lower supporting cylindrical roller assembly and is close to the pressure sensor.
Furthermore, the gravity unloading device also comprises a display device connected with the lower fine adjustment mechanism, and the display device can display the tension and the pressure of the fine adjustment mechanism in real time.
In the technical scheme, the gravity unloading device for the large off-axis three-lens space camera provided by the invention has the following beneficial effects:
the gravity unloading device for the large off-axis three-lens space camera greatly reduces the volume of the fine adjustment mechanism, can apply unloading force to a plurality of points at different positions in space by the mutual matching of the coarse adjustment mechanism and the fine adjustment mechanism, can use a suspension or support mode for each unloading force, and has variable quantity of fine adjustment unloading devices on each guide rail and good adaptability;
the invention can accurately provide the unloading force in the gravity direction no matter supporting unloading or suspension unloading, and each fine adjustment component is provided with the pull/pressure sensor which can monitor the value of the applied force in real time, so that the precision is high;
the coarse adjustment device and the fine adjustment device can be assembled independently and then combined, so that the assembly and disassembly are simple; the cylindrical roller assembly can release the freedom degrees in two directions of a plane and can increase the flexibility of fine adjustment of the unloading piece;
the invention can test by turning 180 degrees under the condition of connecting with the load, and can avoid the error caused by the process of disassembling, turning and re-installing the camera.
Drawings
In order to more clearly illustrate the embodiments of the present application or technical solutions in the prior art, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments described in the present invention, and other drawings can be obtained by those skilled in the art according to the drawings.
Fig. 1 is a schematic view of an overall structure of a front side of a large off-axis three-lens space camera gravity unloading device according to an embodiment of the present invention;
fig. 2 is a schematic view of an overall structure of a side surface of a large off-axis three-lens space camera gravity unloading device according to an embodiment of the present invention;
fig. 3 is a schematic view of an overall structure of a suspension unloading device in a fine adjustment mechanism of a large off-axis three-lens space camera gravity unloading device according to an embodiment of the present invention;
FIG. 4 is a schematic structural diagram of a suspended lower cylindrical roller assembly of a large off-axis three-lens space camera gravity unloading device according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a cylindrical roller and a holding bracket of a gravity unloading device of a large off-axis three-lens space camera according to an embodiment of the present invention;
fig. 6 is a schematic full-sectional view of a suspension unloading device in a fine adjustment mechanism of a large off-axis three-lens space camera gravity unloading device according to an embodiment of the present invention;
fig. 7 is a schematic view of an overall structure of a supporting and unloading device in a fine adjustment mechanism of a large off-axis three-lens space camera gravity unloading device according to an embodiment of the present invention;
fig. 8 is a schematic full-sectional view of a supporting and unloading device in a fine adjustment mechanism of a large off-axis three-lens space camera gravity unloading device according to an embodiment of the present invention.
Description of reference numerals:
1. a base; 2. an end seat; 3. a coarse adjustment mechanism; 4. a fine adjustment mechanism; 5. a display device;
301. (ii) a An upper guide rail; 302. a lower guide rail; 303. a slide bar; 304. a coarse adjustment mechanism position adjustment assembly; 305. unloading the base; 306. a support leg; 307. a camera; 308. a coarse adjustment knob; 309. adjusting the length of the screw rod;
304-1, a motor; 304-2, worm gear transmission mechanism; 304-3, a rack and pinion mechanism; 304-4, a fixed pulley; 304-5, unloading the cable;
401. an upper fine adjustment mechanism; 402. a lower fine adjustment mechanism;
401-1, hanging the unloading device; 401-2, load connection means;
401-1-1, suspending an upper cylindrical roller assembly; 401-1-2, suspending a lower cylindrical roller assembly; 401-1-3, hanging a spherical hinge; 401-1-4, a movable pulley; 401-1-5, hanging an unloading rope; 401-1-6, a ball hinge end cap; 401-1-7, a precise force adjusting device; 401-1-8, a tension sensor;
401-1-2-1, a base; 401-1-2-2, cylindrical roller; 401-1-2-3, holding rack; 401-1-2-4, keeping the stop device;
402-1, supporting and unloading device;
402-1-1, supporting an upper cylindrical roller assembly; 402-1-2, supporting a lower cylindrical roller assembly; 402-1-3, a limiting device; 402-1-4, supporting spherical hinges; 402-1-5, a pressure sensor; 402-1-6, precision force adjusting nut.
Detailed Description
In order to make the technical solutions of the present invention better understood, those skilled in the art will now describe the present invention in further detail with reference to the accompanying drawings.
See fig. 1-8;
the invention discloses a gravity unloading device of a large off-axis three-lens space camera, which comprises:
a base 1 and an end seat 2 which are horizontally arranged; and
the coarse adjustment mechanism 3 further comprises an upper guide rail 301, a lower guide rail 302 and a sliding rod 303 which penetrates through the upper guide rail 301 and the lower guide rail 302 and is connected with the base 1, one end, far away from the base 1, of the sliding rod 303 is connected with the end seat 2, and both the upper guide rail 301 and the lower guide rail 302 can move up and down through the sliding rod 303;
the coarse adjustment mechanism 3 further comprises a coarse adjustment mechanism position adjusting assembly 304, wherein the coarse adjustment mechanism position adjusting assembly 304 is used for adjusting the upper and lower positions of the upper guide rail 301 and the lower guide rail 302;
the upper part and/or the lower part of the coarse adjustment mechanism 3 is/are provided with a fine adjustment mechanism 4, the fine adjustment mechanism 4 positioned at the upper part of the coarse adjustment mechanism 3 is configured as an upper fine adjustment mechanism 401, and the fine adjustment mechanism 4 positioned at the lower part of the coarse adjustment mechanism 3 is configured as a lower fine adjustment mechanism 402;
the base 1 is used for bearing the coarse adjustment mechanism 3 and the fine adjustment mechanism 4.
Further, the coarse adjustment mechanism 3 further includes an unloading base 305; and
a leg 306 connected to the unloading base 305;
a camera 307 connected to the unloading base 305 through the legs 306;
a rough adjusting knob 308 is arranged at one end of the base 1, and the rough adjusting knob 308 is used for adjusting the distance from the lower guide rail 302 to the direction of the unloading base 305;
furthermore, the coarse adjustment mechanism 3 further includes an extension screw 309 having one end connected to the upper rail 301 and the other end connected to the lower rail 302, wherein the extension screw 309 is used for adjusting the distance between the upper rail 301 and the lower rail 302.
Further, the coarse adjustment mechanism position adjustment assembly 304 comprises a motor 304-1 connected to an end of the unloading base 305 away from the leg 306;
a worm gear transmission mechanism 304-2 connected to the output end of the motor 304-1 through a coupling;
two ends of the motor 304-1 are respectively connected with a gear rack mechanism 304-3;
the coarse adjustment mechanism position adjustment assembly 304 further comprises:
the fixed pulleys 304-4 are arranged at the top of the end seat 2 and at the bottom of the base 1; and
and a discharge rope 304-5 connected to the rack and pinion mechanism 304-3 and engaged with the fixed pulley 304-4, wherein the discharge rope 304-5 can drive the upper rail 301 and the lower rail 302 to move up and down.
As a preferable technical solution of this embodiment, the upper fine adjustment mechanism 401 includes a suspension unloading device 401-1 connected to the upper rail 301; and
a load attachment device 401-2 connected at one end to the hang off-load device 401-1 and at the other end to the camera 307.
The embodiment describes the suspension unloading device 401-1 in detail, wherein the suspension unloading device 401-1 comprises a suspension upper cylindrical roller assembly 401-1-1 and a suspension lower cylindrical roller assembly 401-1-2;
a suspension ball joint 401-1-3 having one end connected to the suspension lower cylindrical roller assembly 401-1-2 and the other end connected to the load connection means 401-2;
a movable pulley 401-1-4 connected to the suspended lower cylindrical roller assembly 401-1-2 through a rotating shaft; and
a hanging unloading rope 401-1-5 matched with the movable pulley 401-1-4;
a spherical hinge end cover 401-1-6 is fixed outside the suspension spherical hinge 401-1-3 through a screw;
a precise force adjusting device 401-1-7 arranged at one end of the suspension unloading rope 401-1-5;
a tension sensor 401-1-8 arranged at the other end of the suspension unloading rope 401-1-5.
Further, the suspended lower cylindrical roller assembly 401-1-2 comprises a base 401-1-2-1; and
a plurality of cylindrical rollers 401-1-2-2 disposed inside the base 401-1-2-1;
a holding bracket 401-1-2-3 installed in the base 401-1-2-1, the holding bracket 401-1-2-3 for carrying the cylindrical roller 401-1-2-2;
a retaining and limiting device 401-1-2-4 mounted at one end of the base 401-1-2-1 by screws.
Further, the lower fine adjustment mechanism 402 includes a support unloading device 402-1 having one end fixed to the camera 307 and the other end connected to the lower rail 302.
The present embodiment describes the supporting and unloading device 402-1 in detail, the supporting and unloading device 402-1 includes a supporting upper cylindrical roller assembly 402-1-1 and a supporting lower cylindrical roller assembly 402-1-2;
a limiting device 402-1-3 arranged inside the supporting upper cylindrical roller assembly 402-1-1;
a supporting spherical hinge 402-1-4 connected to the upper part of the supporting upper cylindrical roller assembly 402-1-1;
the lower end of the upper supporting cylindrical roller assembly 402-1-1 is fixedly connected with a pressure sensor 402-1-5;
a precision force adjusting nut 402-1-6 passing through the supporting lower cylindrical roller assembly 402-1-2 and proximate to the pressure sensor 402-1-5.
Preferably, the gravity unloading device further comprises a display device 5 connected to the lower fine adjustment mechanism 402, wherein the display device 5 can display the tension and the pressure of the fine adjustment mechanism 3 in real time.
The working principle is as follows:
the finite element analysis is carried out on the camera structure to determine various implementation schemes, and the parameters are generally the layout mode of the unloading force, the magnitude of each unloading force, the action point position of the unloading force and the like. In order to accurately apply unloading force to the pre-unloading target, firstly, the coarse adjustment knob 308 is adjusted to enable the upper guide rail 301 and the lower guide rail 302 to move to a proper distance in the horizontal direction, so that the vertical projection of the upper unloading guide rail and the lower unloading guide rail covers all unloading points, then the length adjustment screw 309 is adjusted according to the position of the unloading target to adjust the upper guide rail 301 and the lower guide rail 302 to a proper distance, and then suspension type unloading or support type unloading is provided for the unloading points according to the judgment of actual conditions; and then arranging a corresponding number of suspension or support structures on the upper guide rail 301 and the lower guide rail 302 according to the determined unloading scheme, after the unloading structure is fixedly connected with the load, adjusting the vertical positions of the upper guide rail 301 and the lower guide rail 302 by using the driving motor 304-1, and applying a proper amount of load, wherein the upper guide rail 301 and the lower guide rail 302 can be stably positioned to a preset position due to the self-locking characteristic of the worm gear transmission mechanism 304-2. Finally, the accurate force adjusting device 401-1-7 on the suspension unloading device 401-1 and the accurate force adjusting nut 402-1-6 on the supporting unloading device 402-1 are adjusted, the stress of each unloading assembly is adjusted to a set value through the display device 5, and then the reforming gravity unloading process is completed.
The suspension spherical hinge 401-1-3 in the suspension unloading device 401-1, the spherical hinge end cover 401-1-6 and the support spherical hinge 402-1-4 in the support unloading device 402-1 are fixed with a spherical hinge structure through screws, 3-direction rotation freedom degrees can be released, and the two mutually perpendicular cylindrical roller assemblies release the freedom degrees of planes in the horizontal direction and the vertical direction. And 5 degrees of freedom are released, so that only one unloading force opposite to the gravity can be provided, and the non-ideal rotation and translation caused by the inconsistency of the direction or action point of the unloading force with the ideal condition in the unloading process are avoided.
All the hanging and unloading devices 401-1 and the supporting and unloading devices 402-1 can be conveniently installed and detached from the upper guide rail 301 and the lower guide rail 302, and the number of the hanging and unloading devices 401-1 arranged on the upper guide rail 301 and the number of the supporting and unloading devices 402-1 arranged on the lower guide rail 302 can be changed.
In the technical scheme, the gravity unloading device for the large off-axis three-lens space camera provided by the invention has the following beneficial effects:
according to the gravity unloading device for the large off-axis three-lens space camera, the size of the fine adjustment mechanism is greatly reduced through the coarse adjustment device, unloading forces can be applied to a plurality of points at different positions in space through the mutual matching of the coarse adjustment mechanism and the fine adjustment mechanism, each unloading force can be in a hanging or supporting mode, the number of the fine adjustment unloading devices on each guide rail is variable, and the adaptability is good;
the invention can accurately provide the unloading force in the gravity direction no matter supporting unloading or suspension unloading, and each fine adjustment component is provided with the pull/pressure sensor which can monitor the value of the applied force in real time, so that the precision is high;
the coarse adjustment device and the fine adjustment device can be assembled independently and then combined, so that the assembly and disassembly are simple; the cylindrical roller assembly can release the freedom degrees in two directions of a plane and can increase the flexibility of fine adjustment of the unloading piece;
the invention can test by turning 180 degrees under the condition of connecting with the load, and can avoid the error caused by the process of disassembling, turning and re-installing the camera.
While certain exemplary embodiments of the present invention have been described above by way of illustration only, it will be apparent to those of ordinary skill in the art that the described embodiments may be modified in various different ways without departing from the spirit and scope of the invention. Accordingly, the drawings and description are illustrative in nature and should not be construed as limiting the scope of the invention.