A coaxial integrated macro-micro composite driver and control method thereof

Abstract

The present invention discloses a coaxial integrated macro-micro composite driver and a control method thereof, which has the functions of millimeter-level macro-motion and micron-level micro-motion. Under the macro-motion working condition, the macro-motion coil of the driver is turned on, and interacts with the fixed permanent magnet through the magnetic field, driving all internal parts except the fixed part to roll along the axial direction to generate macro-motion displacement. Under the micro-motion working condition, the micro-motion coil of the driver is turned on to generate a magnetic field, so that the thin rod made of giant magnetostrictive material arranged on the central axis is deformed at the non-fixed front end under the action of the magnetic field, and the micro-motion rod is pushed to generate micro-motion displacement along the axial direction. The mutual influence of the two coils when they are turned on is isolated by the magnetic isolation cylinder arranged between them. At the same time, the control method used is also specifically described. The advantages of the coaxial integrated macro-micro composite driver of the present invention are: it can meet the characteristics of large stroke, high precision, heavy load, fast response, no connection error, etc. in the process of precise positioning driving, and at the same time, the overall structure is simple and easy to manufacture.

Description

Technical Field

[0001] The present invention relates to a driving device in the field of precision positioning technology, and more specifically to a coaxial integrated macro-micro composite driver and a control method thereof. Background Art

[0002] With the rapid development of high-end equipment manufacturing industry, the demand for precision positioning worktables with large stroke, high precision, heavy load and fast response is increasing. The macro-micro composite drive mode is the main means to solve the contradiction between large stroke and high precision in precision positioning technology, and is increasingly being adopted in engineering applications. At present, the macro-micro composite drive mode usually adopts a series superposition installation method to arrange the macro-micro two-stage motion structure, that is, the micro-motion mechanism is directly placed on the macro-motion mechanism. This not only makes the overall structure of the worktable complex, but also causes the connection error between the macro-micro two-stage drive due to the installation error. Piezoelectric ceramic drive is the earliest and most mature driving device. In the existing precision positioning worktable with macro-micro composite drive, the micro-displacement drive mainly adopts piezoelectric ceramic drive, but the output force of the piezoelectric ceramic drive is small and it is difficult to meet the demand for heavy load. Therefore, in order to meet the demand of my country's high-end equipment manufacturing industry for precision positioning devices, it is necessary to design a new type of macro-micro composite drive with large stroke, high precision and large thrust and a control method with high precision. Summary of the invention

[0003] The present invention mainly solves the problems existing in the existing drivers, thereby providing a coaxial integrated macro-micro composite driver and its control method which has the characteristics of large stroke, high precision, heavy load, fast response, no connection error, etc. in the process of precise positioning driving, and at the same time has a simple overall structure, is easy to manufacture, and has high control accuracy.

[0004] The above technical problems of the present invention are mainly solved by the following technical solutions:

[0005] A coaxial integrated macro-micro composite driver, comprising a macro-dynamic coil frame, a micro-dynamic coil frame, and a GMM rod, characterized in that: a macro-dynamic coil, a fixed sleeve, and a shell are arranged on the outside of the macro-dynamic coil frame, and a yoke sleeve is arranged on the inside; the macro-dynamic coil is wound in the groove on the outside of the macro-dynamic coil frame, and its positive and negative poles are respectively connected to a wire group; a rolling steel ball row is arranged along its axial direction every sixty degrees around the fixed sleeve, and is nested and arranged on the inside of the shell; the upper surface of the rolling steel ball row is in contact with the shell, and the lower surface is in contact with the macro-dynamic coil, the macro-dynamic coil frame The rear part of the frame contacts with the rear part of the yoke sleeve, so that the macro-dynamic coil can be turned on by the energized wire group and interact with the fixedly arranged arc-shaped permanent magnet through the magnetic field, driving all the components nested in the macro-dynamic coil frame to roll along the axis direction along the lower surface of the rolling steel ball row and generate macro-dynamic displacement toward the front end. A rear end cover is arranged at the rear end of the shell, and six arc-shaped permanent magnets are evenly and fixedly arranged on the inside. The rear end cover is fixedly connected to the shell and the fixed sleeve through a bolt group. A front end cover is tightly arranged at the front end of the yoke sleeve and is nested in the inner side of the macro-dynamic coil frame and the fixed sleeve.

[0006] A micro-motion coil, an inner magnetic yoke tube, a magnetic isolation tube and a magnetic conductive ring are arranged on the outer side of the micro-motion coil skeleton. The micro-motion coil is wound in the groove on the outer side of the micro-motion coil skeleton, and its positive pole and negative pole are respectively connected to the second wire group. The inner magnetic yoke tube is nested in the magnetic isolation tube, and the magnetic isolation tube is nested on the inner side of the magnetic yoke sleeve to avoid mutual influence between the magnetic fields generated when the macro-motion coil and the micro-motion coil are turned on. The magnetic conductive ring is arranged in close contact with the front end of the micro-motion coil skeleton and is nested in the inner magnetic yoke tube.

[0007] The GMM rod is made of giant magnetostrictive material, and a magnetic block group is arranged at its front and rear ends. A micro-motion rod is arranged at the front end of the magnetic block group, and a center bolt is arranged at the rear end. A disc spring is arranged at the front end of the annular end of the micro-motion rod, and they are arranged together in the center groove of the magnetic ring, and keep a certain distance from the rear end of the front end cover. The center bolt fixes the magnetic block group, the GMM rod and the rear end of the micro-motion rod together in the center groove of the micro-motion coil skeleton through the rear end, and can generate a magnetic field when the second wire group of the micro-motion coil is energized, so that the GMM rod is deformed at the non-fixed front end under the action of the magnetic field, pushing the annular end of the micro-motion rod to compress the disc spring and generate micro-motion displacement along the axial direction.

[0008] A control method for a coaxial integrated macro-micro composite actuator, characterized by comprising the following steps:

[0009] S1: Establish macro displacement Xma The current I ma Mathematical model between X ma (I ma ), micro displacement X mi The current I mi Mathematical model between X mi (I mi );

[0010] S2: Find X ma (I ma )The inverse function of the function I ma (X ma ), X mi (I mi )The inverse function of the function I mi (X mi );

[0011] S3: Assume that the distance to be positioned is X0. According to the stroke size of macro-motion and micro-motion, X0 is decomposed into macro-motion displacement X 0a and micro displacement X 0i ;

[0012] S4: According to the inverse function obtained in step S2, the macro coil current I a (X 0a ) and the micro-coil current I i (X 0i );

[0013] S5: Pass current I through the macro coil a , the micro-coil is fed with current I i ;

[0014] S6: Use displacement sensors to detect the size of macro displacement and micro displacement respectively (X 0ac , X 0ic ), and with the set value (X 0a , X 0i ) is compared, and then the feedback control algorithm is used to adjust the error, and finally the positioning distance of X0 is achieved.

[0015] The coaxial integrated macro-micro composite driver and control method thereof of the present invention have the advantages of satisfying the characteristics of large stroke, high precision, heavy load, fast response, no connection error, etc. during the precise positioning driving process, while having a simple overall structure, easy manufacturing, and high control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. It is obvious that the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of a coaxial integrated macro-micro composite actuator of the present invention;

[0018] Figure 2 for Figure 1 Schematic diagram of the three-dimensional cross-sectional structure of the coaxial integrated macro-micro composite actuator;

[0019] Figure 3 for Figure 1 Schematic diagram of the three-dimensional structure of the coaxial integrated macro-micro hybrid driver without the outer shell;

[0020] Figure 4 for Figure 1 Schematic diagram of the working principle of the coaxial integrated macro-micro composite actuator;

[0021] in:

[0022] 20. Wire group 1; 21. Wire group 2;

[0023] 1. External water pipe; 2. Fixed sleeve; 3. Macro-moving coil; 4. Macro-moving coil frame; 5. Magnetic yoke sleeve; 6. Front cover; 7. Disc spring; 8. Micro-moving rod; 9. Magnetic guide ring; 10. Shell; 11. Micro-moving coil frame; 12. Inner yoke cylinder; 13. Magnetic isolation cylinder; 14. Arc permanent magnet; 15. Micro-moving coil; 16. GMM rod; 17. Magnetic guide block group; 18. Rear cover; 22. Center bolt;

[0024] 19. Rolling steel ball train; DETAILED DESCRIPTION

[0025] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

[0026] The coaxial integrated macro-micro composite driver and control method thereof of the present invention have the advantages of satisfying the characteristics of large stroke, high precision, heavy load, fast response, no connection error, etc. during the precise positioning driving process, while having a simple overall structure, easy manufacturing, and high control accuracy.

[0027] like Figure 1 , Figure 2 , Figure 3 , Figure 4 As shown, a coaxial integrated macro-micro composite driver comprises a macro-moving coil frame 4, a micro-moving coil frame 11 and a GMM rod 16. A macro-moving coil 3, a fixed sleeve 2 and a shell 10 are arranged on the outside of the macro-moving coil frame 4, and a yoke sleeve 5 is arranged on the inside. The macro-moving coil 3 is wound in the groove on the outside of the macro-moving coil frame 4, and its positive and negative poles are respectively connected to a wire group 20. A rolling steel ball row 19 is arranged along the axis direction of the fixed sleeve 2 at intervals of sixty degrees around the fixed sleeve 2, and is nested inside the shell 10. The upper surface of the rolling steel ball row 19 contacts the shell 10, and the lower surface contacts the macro-moving coil 3, the rear of the macro-moving coil frame 4 and the yoke. The rear part of the sleeve 5 is in contact, so that the macro-dynamic coil 3 can be turned on by the energized wire group 20, and interact with the fixedly arranged arc-shaped permanent magnet 14 through the magnetic field, driving all the components nested in the macro-dynamic coil skeleton 4 to roll along the lower surface of the rolling steel ball array 19 along the axial direction and generate macro-dynamic displacement toward the front end, thereby realizing millimeter-level macro-drive. A rear end cover 18 is arranged at the rear end of the shell 10, and six arc-shaped permanent magnets 14 are evenly and fixedly arranged on the inside. The rear end cover 18 is fixedly connected to the shell 10 and the fixed sleeve 2 through a bolt group 1. A front end cover 6 is tightly arranged at the front end of the yoke sleeve 5, and is nested on the inner side of the macro-dynamic coil skeleton 4 and the fixed sleeve 2.

[0028] like Figure 1 , Figure 2 As shown, a micro-motion coil 15, an inner magnetic yoke tube 12, a magnetic isolation tube 13, and a magnetic conductive ring 9 are arranged on the outer side of the micro-motion coil skeleton 11. The micro-motion coil 15 is wound in the outer groove of the micro-motion coil skeleton 11, and its positive pole and negative pole are respectively connected to the second wire group 21. The magnetic field generated when it is turned on can be isolated by the magnetic isolation tube 13 to avoid affecting the macro-motion coil 3. The inner magnetic yoke tube 12 is nested in the magnetic isolation tube 13, and the magnetic isolation tube is nested on the inner side of the magnetic yoke sleeve to avoid mutual influence between the magnetic fields generated when the macro-motion coil 3 and the micro-motion coil 15 are turned on. The magnetic conductive ring 9 is arranged closely to the front end of the micro-motion coil skeleton 11 and nested in the inner magnetic yoke tube 12.

[0029] like Figure 1 , Figure 2 , Figure 4As shown, the GMM rod 16 is made of giant magnetostrictive material, and a magnetic block group 17 is arranged at the front and rear ends thereof. A micro-motion rod 8 is arranged at the front end of the magnetic block group 17, and a center bolt 22 is arranged at the rear end. A disc spring 7 is arranged at the front end of the annular end of the micro-motion rod 8, and they are arranged together in the central groove of the magnetic ring 9, and keep a certain distance from the rear end of the front end cover 6. The center bolt 22 fixes the magnetic block group 17, the GMM rod 16 and the rear end of the micro-motion rod 8 together in the central groove of the micro-motion coil skeleton 11 through the rear end, and can generate a magnetic field when the wire group 21 energized by the micro-motion coil 15 is turned on, so that the GMM rod 16 is deformed at the non-fixed front end under the action of the magnetic field, and the annular end of the micro-motion rod 8 is pushed to press the disc spring 7 and generate micro-motion displacement along the axial direction, thereby realizing micro-drive at the micron level.

[0030] A control method for a coaxial integrated macro-micro composite driver, the control method comprising the following steps:

[0031] S1: Establish macro displacement X ma The current I ma Mathematical model between X ma (I ma ), micro displacement X mi The current I mi Mathematical model between X mi (I mi );

[0032] S2: Find X ma (I ma )The inverse function of the function I ma (X ma ), X mi (I mi )The inverse function of the function I mi (X mi );

[0033] S3: Assume that the distance to be positioned is X0. According to the stroke size of macro-motion and micro-motion, X0 is decomposed into macro-motion displacement X 0a and micro displacement X 0i ;

[0034] S4: According to the inverse function obtained in step S2, the macro coil current I a (X 0a ) and the micro-coil current I i (X 0i );

[0035] S5: Pass current I through the macro coil a , the micro-coil is fed with current I i ;

[0036] S6: Use displacement sensors to detect the size of macro displacement and micro displacement respectively (X 0ac , X 0ic ), and with the set value (X 0a , X 0i ) is compared, and then the feedback control algorithm is used to adjust the error, and finally the positioning distance of X0 is achieved.

[0037] like Figure 1 , Figure 2 , Figure 4 As shown, the specific working principle of the coaxial integrated macro-micro composite driver is:

[0038] Macro-dynamic part: The six arc-shaped permanent magnets 14 will generate a constant magnetic field B along the radial direction. Assuming the length of the macro-dynamic coil 3 is L, when the current I is passed through the macro-dynamic coil 3 ma According to Ampere's law, the macro coil 3 will be acted upon by Ampere's force F, whose magnitude is BI ma L, according to the left-hand rule, its direction is along the axial direction of the driver. Under the action of force F, the macro-motion coil frame 4 and all its internal components move along the axial direction with the macro-motion coil 3 to achieve macro-motion. By adjusting I ma The value of I can control the magnitude of the force F. Since the macro-motion coil frame 4 is made of iron, it will be subject to the electromagnetic force F1 of the arc-shaped permanent magnet 14, which prevents it from moving outward. F1 increases as the distance the macro-motion coil frame moves outward increases. When F1 is equal to F, the macro-motion reaches equilibrium. Therefore, the I can be adjusted to ma The value controls the macro displacement value.

[0039] Micro-motion part: Current I is passed through the micro-motion coil 15 mi , it will form an energized solenoid, and generate an axial magnetic field H inside it. Since the GMM rod 16 has a magnetostrictive effect, under the action of the magnetic field strength H, the GMM rod 16 will stretch and deform, pushing the micro-motion rod 8 to compress the disc spring 7, so that the micro-motion rod 8 produces an output displacement, generating micro-motion, and adjusting I mi The value can control the size of the magnetic field H, and then adjust the elongation of the GMM rod 16, so as to achieve micro-movement. ma and I mi The size is worth it, which can realize ultra-precision positioning of the newly designed macro-micro secondary actuator within a large travel range.

[0040] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that are not conceived through creative work should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope defined in the claims.

Claims

1. A control method for a coaxial integrated macro-micro composite actuator, characterized in that The following device is used: comprising a macro-moving coil frame (4), a micro-moving coil frame (11), and a GMM rod (16); a macro-moving coil (3), a fixed sleeve (2), and a shell (10) are arranged outside the macro-moving coil frame (4); a yoke sleeve (5) is arranged inside the macro-moving coil frame (4); the macro-moving coil (3) is wound in a groove outside the macro-moving coil frame (4); its positive pole and negative pole are respectively connected to a wire group (20); a rolling steel ball row (19) is arranged along its axial direction at intervals of sixty degrees around the fixed sleeve (2), and is nested inside the shell (10); the upper surface of the rolling steel ball row (19) is in contact with the shell (10), and the lower surface is in contact with the macro-moving coil (3) and the rear of the macro-moving coil frame (4). and the rear part of the yoke sleeve (5), so that the macro-dynamic coil (3) can be conducted by the energized wire group (20) and interact with the fixedly arranged arc-shaped permanent magnet (14) through the magnetic field, driving all the components nested in the macro-dynamic coil frame (4) to roll along the lower surface of the rolling steel ball array (19) along the axial direction and generate macro-dynamic displacement towards the front end. A rear end cover (18) is arranged at the rear end of the shell (10), and six arc-shaped permanent magnets (14) are evenly and fixedly arranged inside. The rear end cover (18) is fixedly connected to the shell (10) and the fixed sleeve (2) through a bolt group (1). A front end cover (6) is arranged closely at the front end of the yoke sleeve (5) and is nested inside the macro-dynamic coil frame (4) and the fixed sleeve (2); The micro-motion coil frame (11) is installed inside the macro-motion coil frame (4) and shares a central axis with the macro-motion coil frame (4). A micro-motion coil (15), an inner magnetic yoke tube (12), a magnetic isolation tube (13), and a magnetic conductive ring (9) are arranged on the outside of the micro-motion coil frame (11). The micro-motion coil (15) is wound in the outer groove of the micro-motion coil frame (11). Its positive pole and negative pole are respectively connected to the second wire group (21). The inner magnetic yoke tube (12) is nested in the magnetic isolation tube (13). The magnetic isolation tube (13) is nested inside the magnetic yoke sleeve (5) to avoid mutual influence between the magnetic fields generated when the macro-motion coil (3) and the micro-motion coil (15) are turned on. The magnetic conductive ring (9) is arranged in close contact with the front end of the micro-motion coil frame (11) and is nested in the inner magnetic yoke tube (12). The GMM rod (16) is made of giant magnetostrictive material, installed inside the micro-motion coil frame (11), and has a common central axis with the micro-motion coil frame (11). A magnetic block group (17) is arranged at the front and rear ends of the GMM rod (16). A micro-motion rod (8) is arranged at the front end of the magnetic block group (17), and a central bolt (22) is arranged at the rear end. A disc spring (7) is arranged at the front end of the annular end of the micro-motion rod (8), and they are arranged together in the central groove of the magnetic ring (9), and are connected to the rear end of the front cover (6). Keeping a certain distance, the central bolt (22) fixes the magnetic block group (17), the GMM rod (16) and the rear end of the micro-motion rod (8) through the rear end and arranges them together in the central groove of the micro-motion coil frame (11), and the wire group 2 (21) that is energized in the micro-motion coil (15) is turned on to generate a magnetic field, so that the GMM rod (16) is deformed at the non-fixed front end under the action of the magnetic field, pushing the annular end of the micro-motion rod (8) to press the disc spring (7) and generate micro-motion displacement along the axial direction; The control method comprises the following steps: S1: Establish macro displacement X ma The current I ma Mathematical model between X ma (I ma ), micro displacement X mi The current I mi Mathematical model between X mi (Imi); S2: Find X ma (I ma )The inverse function of the function I ma (X ma ), X mi (I mi )The inverse function of the function I mi (X mi ); S3: Assume that the distance to be positioned is X0. According to the stroke size of macro-motion and micro-motion, X0 is decomposed into macro-motion displacement X 0a and micro displacement X 0i ; S4: According to the inverse function obtained in step S2, the macro coil current I a (X 0a ) and the micro-coil current I i (X 0i ); S5: Pass current I through the macro coil a , the micro-coil is fed with current I i ; S6: Use displacement sensors to detect the size of macro displacement and micro displacement respectively (X 0ac , X 0ic ), and with the set value (X 0a , X 0i ) is compared, and then the feedback control algorithm is used to adjust the error, and finally the positioning distance of X0 is achieved.

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