CN109883639B - Three-degree-of-freedom electro-hydraulic control type micro-excitation system - Google Patents
Three-degree-of-freedom electro-hydraulic control type micro-excitation system Download PDFInfo
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- CN109883639B CN109883639B CN201910226045.3A CN201910226045A CN109883639B CN 109883639 B CN109883639 B CN 109883639B CN 201910226045 A CN201910226045 A CN 201910226045A CN 109883639 B CN109883639 B CN 109883639B
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Abstract
The invention discloses a three-degree-of-freedom electro-hydraulic control type micro-excitation system which comprises a base, an excitation platform and three excitation arms, wherein the three excitation arms are arranged at intervals along the circumferential direction. The excitation arm comprises an outer cylinder sleeve, a variable cross-section cylinder, a plug sleeve, a main driving device and an auxiliary driving device. The micro-excitation system can realize vibration excitation in a plurality of directions, namely front and back, left and right, up and down, the output of the excitation platform has 3 translational degrees of freedom, and the micro-excitation system has large-amplitude excitation in a main excitation driving mode and accurate micro-excitation in an auxiliary excitation driving mode so as to meet the requirement of excitation precision.
Description
Technical Field
The invention belongs to the technical field of fluid pressure actuating mechanisms, and particularly relates to a three-degree-of-freedom electro-hydraulic control type micro-excitation system.
Background
In the field of fine operation, performance tests of vibration performance, reliability, high sensitivity and the like are technical problems in the field of high-precision mechanical tests with the characteristics of small structure size, high precision and the like of micro machines (such as micro satellites, micro engines, micro robots and the like), micro devices (micro gyroscopes, micro accelerometers and micro sensors) and the like in the field of aerospace.
At present, in most engineering micro-excitation tests, excitation is provided by adopting an approximate simple one-dimensional (such as a piezoelectric ceramic exciter) or an approximate few-dimensional vibration synthesis micro-vibration table, and vibration excitation in a micro-motion range is difficult to simulate really, so that the problem of how to construct a multi-dimensional micro-vibration excitation table used in a micro-miniature mechanical multi-dimensional vibration test is urgently needed to be solved in the engineering field.
Disclosure of Invention
The invention provides a three-degree-of-freedom electro-hydraulic control type micro-excitation system, which can realize vibration excitation in multiple directions of front and back, left and right, up and down, has 3 translation degrees of freedom in the output of an excitation platform, and has large-amplitude excitation in a main excitation driving mode and accurate micro-excitation in an auxiliary excitation driving mode so as to meet the requirement on excitation precision.
In order to solve the technical problems, the invention adopts the following technical scheme:
a three-degree-of-freedom electro-hydraulic control type micro-excitation system comprises a base, an excitation platform and three excitation arms, wherein the three excitation arms are arranged at intervals along the circumferential direction; the excitation arm comprises an outer cylinder sleeve, a variable cross-section cylinder, a plug sleeve, a main driving device and an auxiliary driving device; wherein the content of the first and second substances,
one end of the outer cylinder sleeve is connected to the base in a sealing mode, one end of the plug sleeve is connected to the excitation platform in a sealing mode through a spherical hinge, the outer side of the other end of the plug sleeve is connected with the other end of the outer cylinder sleeve in a sliding and sealing mode, the inner side of the other end of the plug sleeve is connected with one end of the variable cross-section cylinder in a sliding and sealing mode, and the other end of the variable cross-section cylinder is fixedly connected to the base; one end of the variable cross-section cylinder extending into the plug sleeve is an open end, the auxiliary driving device is arranged on the inner side of the other end of the variable cross-section cylinder, and the main driving device is arranged on the outer side of the other end of the variable cross-section cylinder; and
the main driving device comprises a main piezoelectric ceramic driver and a main annular baffle plate which are of an integrated structure, and the main annular baffle plate is connected to the outer cylinder sleeve and the variable cross-section cylinder through a main flexible hinge; the micro-driving device comprises an auxiliary piezoelectric ceramic driver and an auxiliary circular baffle which are of an integrated structure, and the auxiliary circular baffle is connected to the variable cross-section cylinder through an auxiliary flexible hinge; the main piezoelectric ceramic driver and the auxiliary piezoelectric ceramic driver are both fixedly connected to the base;
the variable cross-section cylinder comprises a large driving section, an amplifying section and a micro-driving section, the micro-driving section is connected to the base, the diameter of the large driving section is larger than that of the micro-driving section, and the diameter of the amplifying section gradually decreases from the large driving section to the micro-driving section;
the plug sleeve and the outer cylinder sleeve are connected to an oil tank through a first switch valve and a second switch valve respectively.
In a preferred embodiment, the excitation platform is approximately in the shape of an equilateral triangle.
In a preferred embodiment, the base includes a base approximately in the shape of an equilateral triangle and a support portion extending obliquely from three ends of the base, and the excitation arm is connected to the support portion.
In a preferred embodiment, the excitation arm is vertically connected with the supporting part.
In a preferred embodiment, the three-degree-of-freedom electro-hydraulic control type micro-excitation system further includes a controller, and the controller is electrically connected to the main piezoelectric ceramic driver and the auxiliary piezoelectric ceramic driver of the three excitation arms, respectively.
In a preferred embodiment, the control information output by the controller is a pulse signal with adjustable frequency.
In a preferred embodiment, the main drive surrounds the variable cross-section cylinder.
In a preferred embodiment, the side surface of the enlarged section of the variable cross-section cylinder is arc-shaped or conical.
In a preferred embodiment, in an initial working state, an included angle of 120 degrees is formed between the excitation arm and the excitation platform.
In a preferred embodiment, the movement locus of the sleeve comprises a linear reciprocating movement locus and a movement locus linearly moving to the target point.
The invention has the following beneficial effects:
1. the three-degree-of-freedom electro-hydraulic control type micro-excitation system disclosed by the invention adopts a main excitation mode (in the working state of the main piezoelectric ceramic driver) and an auxiliary excitation mode (in the working state of the auxiliary piezoelectric ceramic driver), integrates large-amplitude excitation in the main excitation driving mode and accurate micro-excitation in the auxiliary excitation driving mode, and meets the requirement on excitation precision.
2. The three excitation arms are connected with the excitation platform at obtuse angles (preferably 120 degrees in an initial working state), so that the size of the micro-excitation system can be reduced, the space is compact, and accurate excitation and large-amplitude excitation under the limited volume can be simultaneously ensured in the micro-excitation.
Drawings
Fig. 1 is a schematic structural diagram of a three-degree-of-freedom electro-hydraulic control type micro-excitation system according to an embodiment of the present invention;
FIG. 2 is a schematic partial cross-sectional view of a three-degree-of-freedom electro-hydraulic control type micro-excitation system;
fig. 3 is a schematic cross-sectional view of the excitation arm.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1 to 3, the invention discloses a three-degree-of-freedom electro-hydraulic control type micro-excitation system, which comprises a base 10, an excitation platform 20 and three excitation arms 30. In the embodiment shown in the drawings, the excitation platform 20 is approximately in the shape of an equilateral triangle, and the base 10 includes a base 11 approximately in the shape of an equilateral triangle and a support 4 extending obliquely from three ends of the base 11.
The three excitation arms 30 are uniformly arranged at intervals along the circumferential direction, and two ends of the excitation arms 30 respectively correspond to the end part of the excitation platform 20 and the end part of the base 10. The excitation arm 30 is of a cylindrical structure as a whole, adopts a dual-drive and electro-hydraulic control mode, and comprises an outer cylinder sleeve 1, a variable-section cylinder 2, a plug sleeve 3, a main drive device and an auxiliary drive device.
One end of the outer cylinder sleeve 1 is hermetically connected to the supporting part 4 (the circumferential direction of the exciting arm 30 is perpendicular to the surface of the supporting part 4), and one end of the plug sleeve 3 is hermetically connected to the end of the exciting platform 20 through a spherical hinge, so that a closed oil-filled cavity is formed inside the exciting arm 30. The outer side of the other end of the plug sleeve 3 is connected with the other end of the outer cylinder sleeve 1 in a sliding and sealing mode, the inner side of the other end of the plug sleeve 3 is connected with one end of the variable-section cylinder 2 in a sliding and sealing mode, and the sliding seals at the two positions are matched to achieve the vibration excitation action of the plug sleeve 3 better.
The end of the variable cross-section cylinder 2 extending into the plug bush 3 is an open end, the open end provides oil for the plug bush 3 to realize micro-displacement excitation, and the oil is driven by an auxiliary driving device arranged on the inner side of the other end of the variable cross-section cylinder 2. The main driving device is arranged on the outer side of the other end of the variable cross-section cylinder 2 and is used for driving oil liquid on the outer side of the variable cross-section cylinder 2 to realize large-displacement excitation of the plug bush 3.
The main driving device comprises a main piezoelectric ceramic driver 51 and a main annular baffle 52 which are of an integrated structure, and the main annular baffle 52 is connected to the outer cylinder sleeve 1 and the variable-section cylinder 2 through a main flexible hinge 53; the micro-driving device comprises an auxiliary piezoelectric ceramic driver 61 and an auxiliary circular baffle 62 which are of an integrated structure, and the auxiliary circular baffle 62 is connected to the variable-section cylinder 2 through an auxiliary flexible hinge 63; the main piezoelectric ceramic driver 51 and the auxiliary piezoelectric ceramic driver 61 are both fixedly connected to the support portion 4. The main flexible hinge 53 and the auxiliary flexible hinge 63 are respectively used for restoring the main circular baffle 52 and the auxiliary circular baffle 62 to the original state when the main piezoelectric ceramic driver 51 and the auxiliary piezoelectric ceramic driver 61 stop working.
In a particular embodiment, the main drive surrounds the variable-section cylinder 2.
The variable cross-section cylinder 2 comprises a large driving section, an amplifying section and a micro-driving section, the micro-driving section is connected to the supporting part 4, the diameter of the large driving section is larger than that of the micro-driving section, and the diameter of the amplifying section is gradually decreased from the large driving section to the micro-driving section. The different diameters of the variable section cylinder 2 are designed for the purpose of:
1) when oil flows into the large-diameter large-driving-section inner chamber from the small-diameter micro-driving-section inner chamber, the displacement of the plug sleeve 3 is reduced compared with that of the auxiliary circular baffle 62 because the cross section through which the oil flows is changed from small to large;
2) when oil flows into the outer cavity of the large driving section from the outer cavity of the micro driving section, the cross section through which the oil flows is reduced, so that the displacement of the plug bush 3 is amplified compared with that of the main annular baffle 52.
In a particular embodiment, the lateral surface of the enlargement section of the variable-section cylinder 2 is curved or tapered to achieve different enlargement/reduction factors.
Although the internal chamber of the excitation arm 30 is of a closed structure, in order to achieve linear reciprocating motion of the sleeve 3 (i.e., positive and negative displacement excitation), the flow continuity of the oil is maintained, and therefore, the sleeve 3 and the outer cylinder liner 1 are connected to the oil tank 7 through the first switching valve 71 and the second switching valve 72, respectively.
In order to precisely excite the excitation arms 30 and the combined excitation between the excitation arms 30 to control the operating states of the main piezoelectric ceramic driver 51 and the auxiliary piezoelectric ceramic driver 61, the micro excitation system further includes a controller (e.g., a PID controller) electrically connected to the main piezoelectric ceramic driver 51 and the auxiliary piezoelectric ceramic driver 61, respectively. The single excitation arm 30 can generate excitation in a single direction, that is, precise excitation motion of the object to be excited can be realized; for some complex excitation modes, different combinations of 2 or 3 excitation arms 30 are needed to perform multi-degree-of-freedom combined excitation, that is, the excitation requirements are met by changing the outputs of different excitation arms 30. Specifically, the control information output by the controller is a pulse signal with adjustable frequency to match different excitation requirements.
In one embodiment, the movement trajectory of the sleeve 3 includes a linear reciprocating movement trajectory (excitation mode) and a movement trajectory that moves linearly to a target point (fine positioning control).
It is to be understood that the exemplary embodiments described herein are illustrative and not restrictive. Although one or more embodiments of the present invention have been described with reference to the accompanying drawings, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims.
Claims (10)
1. The three-degree-of-freedom electro-hydraulic control type micro-excitation system is characterized by comprising a base, an excitation platform and three excitation arms, wherein the three excitation arms are arranged at intervals along the circumferential direction; the excitation arm comprises an outer cylinder sleeve, a variable cross-section cylinder, a plug sleeve, a main driving device and an auxiliary driving device; wherein the content of the first and second substances,
one end of the outer cylinder sleeve is connected to the base in a sealing mode, one end of the plug sleeve is connected to the excitation platform in a sealing mode through a spherical hinge, the outer side of the other end of the plug sleeve is connected with the other end of the outer cylinder sleeve in a sliding and sealing mode, the inner side of the other end of the plug sleeve is connected with one end of the variable cross-section cylinder in a sliding and sealing mode, and the other end of the variable cross-section cylinder is fixedly connected to the base; one end of the variable cross-section cylinder extending into the plug sleeve is an open end, the auxiliary driving device is arranged on the inner side of the other end of the variable cross-section cylinder, and the main driving device is arranged on the outer side of the other end of the variable cross-section cylinder; and
the main driving device comprises a main piezoelectric ceramic driver and a main annular baffle plate which are of an integrated structure, and the main annular baffle plate is connected to the outer cylinder sleeve and the variable cross-section cylinder through a main flexible hinge; the auxiliary driving device comprises an auxiliary piezoelectric ceramic driver and an auxiliary circular baffle which are of an integrated structure, and the auxiliary circular baffle is connected to the variable cross-section cylinder through an auxiliary flexible hinge; the main piezoelectric ceramic driver and the auxiliary piezoelectric ceramic driver are both fixedly connected to the base;
the variable cross-section cylinder comprises a large driving section, an amplifying section and a micro-driving section, the micro-driving section is connected to the base, the diameter of the large driving section is larger than that of the micro-driving section, and the diameter of the amplifying section gradually decreases from the large driving section to the micro-driving section;
the plug sleeve and the outer cylinder sleeve are connected to an oil tank through a first switch valve and a second switch valve respectively.
2. The three degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 1, wherein the excitation platform is approximately in an equilateral triangle.
3. The three-degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 2, wherein the base comprises a base approximately in the shape of an equilateral triangle and support portions extending obliquely from three ends of the base, and the excitation arm is connected to the support portions.
4. The three-degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 3, wherein the excitation arm is vertically connected with the support part.
5. The three-degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 1, further comprising a controller, wherein the controller is electrically connected to the main piezoelectric ceramic driver and the auxiliary piezoelectric ceramic driver of the three excitation arms, respectively.
6. The three degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 5, wherein the control information output by the controller is a pulse signal with adjustable frequency.
7. The three degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 1, wherein the main driving device surrounds the variable cross-section cylinder.
8. The three-degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 1, wherein the side surface of the amplification section of the variable cross-section cylinder is arc-shaped or conical.
9. The three-degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 1, wherein in an initial working state, an included angle of 120 degrees is formed between the excitation arm and the excitation platform.
10. The three-degree-of-freedom electro-hydraulic control type micro-excitation system as claimed in claim 1, wherein the motion trail of the plug bush comprises a straight reciprocating motion trail and a motion trail of the straight motion to a target point.
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| CN201910226045.3A CN109883639B (en) | 2019-03-25 | 2019-03-25 | Three-degree-of-freedom electro-hydraulic control type micro-excitation system |
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| CN201910226045.3A CN109883639B (en) | 2019-03-25 | 2019-03-25 | Three-degree-of-freedom electro-hydraulic control type micro-excitation system |
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