Dual-actuated vibration isolation device and vibration isolation control method thereof

Abstract

The present application belongs to the field of vibration isolation, and particularly relates to a double-actuator vibration isolation device and a vibration isolation control method thereof. The present application constructs a systematic solution of "series topology, sensing configuration and decoupling control". By arranging piezoelectric ceramic actuators and voice coil actuators in a dynamic series along a main transmission path, and based on a multi-point information fusion cooperative control strategy, high-performance integrated suppression of full-band vibration from low frequency to medium-high frequency is realized in principle, while ensuring extremely high static and dynamic support stiffness of the system. The present application ingeniously solves the inherent limitations of single actuators in physical characteristics based on the hybrid actuation mode of voice coil actuators and piezoelectric ceramic actuators. The characteristics of large output force and high stiffness of piezoelectric ceramic actuators are used to actively compensate for the foundation vibration in a wide frequency range; the characteristics of large stroke and fast response speed of voice coil actuators are used to actively suppress the system resonance peak, thereby improving the vibration isolation performance of the system in a wide frequency range.

Description

Technical Field

[0001] This invention belongs to the field of vibration isolation technology, and particularly relates to a dual-actuation vibration isolation device and its vibration isolation control method. Background Technology

[0002] With the rapid development of advanced manufacturing fields such as precision manufacturing, optical instruments, and aerospace, the requirements for vibration control in the working environment have reached extremely high levels. Wideband vibration isolation performance usually requires the system to have a low natural frequency, while disturbance rejection capability requires the system to have high stiffness. This inherent contradiction in physical characteristics often causes traditional systems to fail in one aspect when facing complex working conditions with high disturbance rejection and wide frequency range, and may even lead to system instability due to insufficient stiffness.

[0003] Traditional passive vibration isolation systems are limited by physical laws. While they exhibit good attenuation capabilities at high frequencies, they inevitably possess a resonance amplification region at low frequencies, making it difficult to meet the stringent requirements of modern precision instruments for full-frequency vibration isolation. To overcome the limitations of passive vibration isolation, active vibration isolation technology has emerged. Currently, the mainstream active vibration isolation actuators mainly employ piezoelectric ceramics and voice coil motors. However, both have significant single-stage limitations in their physical characteristics: piezoelectric ceramic actuators, while possessing advantages such as high stiffness and large thrust, can effectively suppress low-frequency, high-volume vibrations transmitted from the foundation. However, their inherent hysteresis characteristics introduce nonlinear features in the mid-to-high frequency range, limiting the system's performance in wideband vibration control. Voice coil motors, on the other hand, have excellent linearity and a wide response bandwidth, performing well in compensating for mid-to-high frequency vibrations. However, their zero-stiffness characteristics result in insufficient suppression of low-frequency disturbances.

[0004] To balance high disturbance rejection capability with wide-band vibration isolation performance, existing technologies combine actuators to achieve complementary advantages. However, while current vibration isolation technologies have attempted to combine different actuators, most lack system-level dynamic matching and in-depth collaborative control strategies, failing to resolve the fundamental contradictions at the system architecture and control level. These solutions often result in complex force transmission path coupling and mutual interference in control loops, failing to truly achieve the complementarity and synergy of the two actuator advantages. Essentially, they remain performance compromises with unsatisfactory results. Summary of the Invention

[0005] In view of this, the present invention aims to provide a dual-actuation vibration isolation device and its vibration isolation control method to solve the problems of limited single drive performance, failure of the hybrid actuation architecture, uncontrollable intermediate stage state and severe control coupling in the prior art. The present invention adopts a hybrid actuation strategy of voice coil motor and piezoelectric ceramic, combining the advantages of both, and provides an ideal ultra-static and stable working environment for the system at the active control level.

[0006] To achieve the above objectives, the technical solution created by this invention is implemented as follows: A dual-actuation vibration isolation device includes: a dual-stage actuation vibration isolation unit, a signal acquisition module, and a hierarchical collaborative control module; The dual-stage actuation vibration isolation unit includes a base, an intermediate platform, a load platform, a piezoelectric ceramic vibration isolation unit and a rigid guide connected in parallel between the base and the intermediate platform, and a voice coil motor vibration isolation unit and a flexible guide connected in parallel between the intermediate platform and the load platform. The signal acquisition module includes a first velocity sensor mounted on the base, a second velocity sensor mounted on the intermediate platform, and a third velocity sensor mounted on the load platform. Each sensor is used to acquire vibration signals at its respective location. The hierarchical collaborative control module includes a feedforward control loop, a displacement servo feedback control loop, and a velocity feedback control loop. The feedforward control loop is based on the acquisition results of the first velocity sensor, the displacement servo feedback control loop is based on the acquisition results of the second velocity sensor, and the velocity feedback control loop is based on the acquisition results of the third velocity sensor, to perform feedforward and feedback composite control on the two-stage actuation vibration isolation unit.

[0007] Furthermore, the piezoelectric ceramic vibration isolation unit is connected to the base through no fewer than three rigid guide members; the voice coil motor vibration isolation unit is connected to the intermediate platform through no fewer than three flexible guide members.

[0008] Furthermore, the piezoelectric ceramic vibration isolation unit includes a piezoelectric housing for mounting an intermediate platform, and a piezoelectric ceramic actuator disposed inside the piezoelectric housing, the actuating displacement of the piezoelectric ceramic actuator acting between the piezoelectric housing and the base.

[0009] Furthermore, the voice coil motor vibration isolation unit includes a voice coil housing and a voice coil actuator disposed inside the voice coil housing. The voice coil housing is used to mount the load platform. The mover and stator of the voice coil actuator are respectively mounted on the intermediate platform and the inner surface of the voice coil housing. The output force of the voice coil motor acts between the voice coil housing and the intermediate platform.

[0010] Furthermore, the flexible guide includes a flexible hinge, one end of which is fixedly connected to the voice coil housing, and the other end of which is fixedly connected to the intermediate platform; one end of the rigid guide is fixedly connected to the piezoelectric housing, and the other end of which is fixedly connected to the base.

[0011] A vibration isolation control method for a dual-actuation vibration isolation device, which utilizes the dual-actuation vibration isolation device, specifically includes the following steps: S1: The dual-actuation vibration isolation device starts working. At time i, the first velocity sensor collects the disturbance velocity signal at the foundation, the second velocity sensor collects the first absolute motion velocity signal, and the third velocity sensor collects the second absolute motion velocity signal. S2: The feedforward control loop drives the piezoelectric ceramic actuator to generate a displacement opposite to the direction of the disturbance based on the disturbance velocity signal at the base. The displacement servo feedback control loop integrates the first absolute motion velocity signal and converts it into a displacement signal, driving the piezoelectric ceramic actuator to output the actuation displacement. S3: The speed feedback control loop drives the voice coil motor actuator to apply active damping based on the second absolute motion speed signal; S4: Replace time i with time i+1, and repeat steps S1-S3 until the dual-actuated vibration isolation device finishes working, thus completing the vibration isolation control of the dual-actuated vibration isolation device.

[0012] Furthermore, the dynamic model of the feedforward control loop is as follows: ; in, This is the feedforward control output signal. This is the feedforward control transfer function. Let be the transfer function of a first-order low-pass filter. This is for feedforward control of the output displacement of the piezoelectric ceramic actuator. For feedforward gain, The perturbation velocity signal at the base.

[0013] Furthermore, the dynamic model of the displacement servo feedback control loop is as follows: ; in, This is the output signal for displacement servo feedback control. This is the transfer function for displacement servo feedback control. Let be the transfer function of a first-order low-pass filter. The displacement is output by the piezoelectric ceramic actuator for displacement servo feedback control. For displacement servo feedback gain, For Laplace variables, This is the first absolute velocity signal.

[0014] Furthermore, the dynamic model of the speed feedback control loop is as follows: ; in, For speed feedback control output signal, For the velocity feedback transfer function, Here is the transfer function of the high-pass filter. For speed signal, For speed feedback gain, This is the second absolute velocity signal.

[0015] Compared with the prior art, the present invention can achieve the following beneficial effects: (1) The dual-actuator vibration isolation device and its vibration isolation control method described in this invention solve the inherent contradiction between wideband vibration isolation performance and high anti-interference capability in principle. This invention enables the piezoelectric ceramic actuator to fully utilize its high-frequency response and high-power output characteristics in the high-stiffness path, focusing on disturbance feedforward cancellation and low-frequency suppression; at the same time, it enables the voice coil actuator to utilize its advantages of large stroke and high linearity in the low-stiffness path, focusing on high-frequency suppression and damping injection. Through the above design, the system can significantly extend the effective vibration isolation frequency band downward while maintaining extremely high static support stiffness, achieving comprehensive performance that cannot be achieved by traditional single-actuator mode or simple composite architecture.

[0016] (2) The dual-actuation vibration isolation device and its vibration isolation control method described in this invention cleverly solve the inherent limitations of the physical characteristics of a single actuator by using a hybrid actuation mode of voice coil actuator and piezoelectric ceramic actuator. The large output and high stiffness characteristics of the piezoelectric ceramic actuator are used to compensate for low-frequency large-amplitude shaking and static displacement; the zero friction and high response characteristics of the voice coil actuator are used to isolate mid-to-high frequency micro-amplitude vibrations, thereby achieving wide-band efficient isolation.

[0017] (3) The dual-actuator vibration isolation device and its vibration isolation control method described in this invention adopt a feedforward and feedback composite control strategy, comprehensively utilizing multi-source sensor information installed at the base, intermediate platform, and load platform to design a collaborative control strategy for the voice coil actuator and the piezoelectric ceramic actuator. Through frequency domain separation technology, the coupling interference between the two actuators is resolved, enabling the piezoelectric ceramic actuator to achieve pre-cancellation of feedforward control and control of low-frequency vibration, while the voice coil actuator achieves suppression of system resonance, thereby achieving the collaborative vibration isolation task in the target frequency band.

[0018] (4) The dual-actuator vibration isolation device and its vibration isolation control method described in this invention encapsulate the piezoelectric-voice coil collaborative architecture into a self-contained, self-stabilizing, and interface-standard functional module. This vibration isolation system has achieved a strategy of decoupling the dynamic frequency domain function at the physical level and coordinating control of the dual actuators. Therefore, when splicing vibration isolation systems, no new harmful couplings or stiffness conflicts are introduced between the various vibration isolation systems. This allows multiple vibration isolation systems to be quickly and reliably spliced ​​into a three-degree-of-freedom translational or six-degree-of-freedom full-dimensional vibration isolation platform simply through a mechanical connection and a unified electrical bus. The entire expansion process does not require complex overall redesign or tedious coupling debugging, thereby greatly reducing the engineering integration complexity, time, and cost of high-end vibration isolation systems while ensuring system performance. This strongly demonstrates that the dual-actuator scheme not only has superior performance but also excellent engineering practicality and scalability. Attached Figure Description

[0019] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 A schematic diagram of the structure of the two-stage actuation vibration isolation device described in the embodiment of the present invention; Figure 2 A schematic diagram of the dynamic model of the two-stage actuation vibration isolation device described in the embodiment of the present invention; Figure 3 A schematic diagram illustrating the configuration of each sensor described in the embodiments of the present invention; Figure 4 A flowchart of the hierarchical collaborative control module described in the embodiments of the present invention; Figure 5 A schematic diagram of the structure of the flexible guide described in the embodiment of the present invention; Figure 6 A schematic diagram of the rigid guide member described in the embodiment of the present invention; Figure 7 A schematic diagram of the anti-torsion groove structure described in the embodiment of the present invention; Figure 8 A schematic diagram of the structure of the base described in the embodiment of the present invention; Figure 9 A schematic diagram of the structure of the three-degree-of-freedom vibration isolation system described in the embodiment of the present invention; Figure 10 A schematic flowchart of the vibration isolation control method of the dual-actuator vibration isolation device described in the embodiments of the present invention; Figure 11 Experimental effect diagram of the dual-actuation vibration isolation device described in the embodiment of the present invention.

[0020] Explanation of reference numerals in the attached figures: 1. Voice coil motor vibration isolation unit; 2. Flexible guide component; 3. Intermediate platform; 4. Rigid guide component; 5. Piezoelectric ceramic vibration isolation unit; 6. Base; 7. Anti-torsion groove structure; 8. Upper platform; 9. Lower platform; 10. Support leg rigid guide mechanism; 51. Piezoelectric housing. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0026] like Figure 1 As shown, the present invention proposes a dual-actuation vibration isolation device comprising: a dual-stage actuation vibration isolation unit, a signal acquisition module, and a hierarchical collaborative control module; The dual-stage actuation vibration isolation unit includes a base 6, an intermediate platform 3, a load platform, a piezoelectric ceramic vibration isolation unit 5 and a rigid guide 4 connected in parallel between the base 6 and the intermediate platform 3, and a voice coil motor vibration isolation unit 1 and a flexible guide 2 connected in parallel between the intermediate platform 3 and the load platform. The signal acquisition module includes a first velocity sensor mounted on the base 6, a second velocity sensor mounted on the intermediate platform 3, and a third velocity sensor mounted on the load platform. Each sensor is used to acquire vibration signals at its respective position. The hierarchical collaborative control module includes a feedforward control loop, a displacement servo feedback control loop, and a velocity feedback control loop. The feedforward control loop is based on the acquisition results of the first velocity sensor, the displacement servo feedback control loop is based on the acquisition results of the second velocity sensor, and the velocity feedback control loop is based on the acquisition results of the third velocity sensor, to perform feedforward and feedback composite control on the two-stage actuation vibration isolation unit.

[0027] It should be noted that this invention constructs a three-in-one systematic solution of "serial topology, sensor configuration, and decoupled control". By dynamically arranging the piezoelectric ceramic actuator and the voice coil actuator in series along the main transmission path, and cooperating with a collaborative control strategy based on multi-point information fusion, high-performance integrated suppression of vibrations across the entire frequency range from low to mid-high frequencies is achieved in principle, while ensuring extremely high static and dynamic support stiffness of the system.

[0028] Specifically, this invention employs a dynamic series topology, placing the piezoelectric ceramic actuator in a high-stiffness path to perform rigid support and low-frequency compensation tasks, while placing the voice coil actuator in a low-stiffness path to perform flexible connection and high-frequency energy absorption tasks. This creates an optimal working environment for both actuators from a physical architecture perspective, achieving excellent vibration isolation performance across the entire frequency range and laying the hardware foundation for frequency domain functional separation. Furthermore, by arranging sensors at multiple key points such as the base 6, intermediate platform 3, and load platform, a multi-layered information sensing network capable of simultaneously sensing disturbance input, internal state, and final output is constructed, providing data support for precise collaborative control. In addition, a collaborative control strategy centered on feedforward-feedback is proposed. The piezoelectric ceramic actuator primarily undertakes low-frequency compensation and rigid support functions based on feedforward and internal feedback, while the voice coil actuator primarily undertakes high-frequency energy absorption and system damping injection functions based on absolute feedback, thereby achieving integrated, high-performance active vibration suppression across the entire frequency range from low to mid-high frequencies.

[0029] Furthermore, such as Figure 2As shown, the dual-stage actuated vibration isolation unit is a series-type dual-stage active vibration isolation dynamic model. This model abstracts the dual-actuated vibration isolation device as follows: the foundation is connected to the intermediate mass (M1, in dynamic modeling, the intermediate platform 3 and the piezoelectric shell 51 are equivalent to the intermediate mass M1) via a parallel dual-actuated vibration isolation device consisting of a large stiffness spring (K1) and a piezoelectric ceramic actuator (PZT); the intermediate mass (M1) is then connected to the load mass (M2, i.e., the load platform) via a parallel dual-actuated vibration isolation device consisting of a small stiffness spring (K2) and a voice coil actuator (VCM). This model intuitively reveals the dynamic series topology and stiffness differentiation design concept of this invention: the lower high-stiffness path uses a large stiffness elastic support connected in parallel with a large thrust displacement actuator to construct a rigid displacement compensation channel to follow and offset the large-amplitude low-frequency vibration of the foundation; the upper low-stiffness path uses a small stiffness elastic support connected in parallel with a zero-stiffness voice coil actuator to construct a flexible force control channel to block high-frequency transmission and suppress system resonance. By configuring differentiated structural stiffness, the mechanical support structure is adapted to the physical characteristics of the dual actuators, laying the foundation for the collaborative operation of the dual actuators.

[0030] like Figure 3 As shown, to achieve accurate state perception and decoupled control of the above dynamic model, this invention arranges a high-precision velocity sensor on the base 6, the intermediate mass, and the load platform respectively. Specifically: the first velocity sensor (VS1) is arranged on the base 6 to measure the ground input disturbance and serve as a feedforward control signal source; the second velocity sensor (VS2) is arranged on the intermediate mass (M1) to monitor the absolute motion state of the intermediate level, that is, to monitor the dynamic state inside the two-stage actuator series structure. The signal is integratored to obtain the displacement signal, which serves as the displacement servo feedback signal; the third velocity sensor (VS3) is arranged on the load platform (M2) to evaluate the final vibration isolation effect and serve as the absolute velocity feedback signal. Ce is the equivalent damping of the voice coil motor, and Cc is the equivalent damping of the piezoelectric ceramic. Based on the design layout of the three-point absolute vibration sensing, the entire link state information from disturbance input, internal transmission to final output is completely depicted, providing an information basis for the efficient realization of feedforward and feedback composite control. Its upper flexible and lower rigid guiding design ensures that the dual actuators work in the optimal dynamic environment.

[0031] like Figure 4As shown, based on the aforementioned dynamic model and sensor configuration, this invention proposes a multi-point sensor information fusion feedforward-feedback composite hierarchical control system to achieve differentiated and precise coordination of two-stage actuators. According to the characteristics of the sensor signals and actuators, the control strategy is implemented as three parallel control paths. Feedforward control loop: Based on the signal from the first velocity sensor (VS1), the feedforward controller drives the piezoelectric ceramic actuator (PZT) to generate a reverse displacement, cutting off the transmission path of the basic disturbance at the physical source, aiming to keep the intermediate inertial stage stationary relative to the inertial space. Displacement servo feedback control loop: Based on the signal from the second velocity sensor (VS2), the signal is converted into a displacement signal by an integrator, driving the piezoelectric ceramic actuator (PZT) to precisely adjust the low-frequency residual vibration of the intermediate mass, maintaining internal attitude stability. Absolute velocity feedback loop: Based on the signal from the third velocity sensor (VS3), the voice coil actuator (VCM) applies virtual damping between the load and the inertial space, strongly suppressing system resonance peaks and attenuating mid-to-high frequency micro-amplitude disturbances. The three control paths work together to achieve full-link, wide-frequency-domain high-performance active vibration isolation, which includes pre-elimination at the source, fine adjustment in the transmission path, and damping at the load end.

[0032] In some embodiments, the piezoelectric ceramic vibration isolation unit 5 is connected to the base 6 via no less than three rigid guide members 4; the voice coil motor vibration isolation unit 1 is connected to the intermediate platform 3 via no less than three flexible guide members 2.

[0033] Flexible guide 2 and rigid guide 4 are respectively as follows Figure 5 and Figure 6 As shown.

[0034] Furthermore, the rigid guide 4 and the flexible guide 2 are used to uniformly constrain the double-layer vibration isolation unit in the circumference, suppress lateral coupling displacement and overturning rotation, thereby ensuring that the double-acting vibration isolation device achieves strict single-degree-of-freedom motion during operation.

[0035] The rigid guide 4 employs a three-leg structure with high rigidity, arranged at 120° intervals along the circumference. This high-rigidity leg structure is designed to accommodate the high-rigidity output characteristics of the piezoelectric ceramic actuator, providing stable guidance and rigid support for the piezoelectric ceramic vibration isolation unit 5. Furthermore, the high-rigidity leg structure itself suppresses internal disturbances transmitted by the voice coil motor vibration isolation unit 1.

[0036] The flexible guide 2 employs a three-leg structure with leaf spring-type flexible hinges, arranged at 120° intervals along the circumference. This flexible guide 2 utilizes a leaf spring-type flexible hinge leg structure to adapt to the actuation characteristics of the voice coil motor, providing a certain degree of flexibility to the voice coil motor isolation unit 1 while ensuring guiding accuracy. Simultaneously, by controlling the fundamental frequency of the piezoelectric ceramic isolation unit 5 at 25 Hz, the flexible guide 2 possesses both necessary stiffness and disturbance rejection capability to meet the dynamic response and stable support requirements of the voice coil motor isolation unit 1. It is important to emphasize that the design target for the fundamental frequency of the voice coil motor isolation unit 1 is 25 Hz, aiming to achieve the optimal balance between passive flexibility and structural disturbance rejection capability. Based on the fact that the stiffness of a dual-actuation vibration isolation device is proportional to the square of its natural frequency, compared to a typical 1 Hz ultra-low frequency vibration isolation system, the 25 Hz fundamental frequency design significantly amplifies the equivalent stiffness by 625 times under the same load-bearing mass. This moderately enhanced stiffness characteristic enables it to effectively resist dynamic disturbances caused by internal moving parts or external sudden loads in dual-actuated vibration isolation devices, thereby reducing the effectiveness of passive high-frequency vibration isolation.

[0037] In some embodiments, the piezoelectric ceramic vibration isolation unit 5 includes a piezoelectric housing 51 for mounting the intermediate platform 3, and a piezoelectric ceramic actuator disposed inside the piezoelectric housing 51, wherein the actuation displacement of the piezoelectric ceramic actuator acts between the piezoelectric housing 51 and the base 6.

[0038] It should be noted that the top of the piezoelectric ceramic actuator is fitted with the piezoelectric housing 51 through the anti-torsion groove structure 7 to prevent torsion, and its bottom is fixed to the base 6 by a gasket.

[0039] It should be noted that, due to the very low torsional strength of piezoelectric ceramic actuators, an anti-torsion groove structure 7 matching the top structure of the piezoelectric ceramic actuator is provided inside the piezoelectric housing 51. The anti-torsion groove is a positioning structure used in mechanical connections to limit relative rotation and transmit torque. Its core function is to prevent circumferential rotation of components after assembly, ensuring the reliability and positioning accuracy of the connection. Figure 8 As shown, a square (or rectangular) groove (anti-torsion groove) is formed on the inner wall of the central inner hole, and a corresponding key, pin or boss of the connected part can be matched in the groove.

[0040] In some embodiments, the voice coil motor vibration isolation unit 1 includes a voice coil housing and a voice coil actuator disposed inside the voice coil housing. The voice coil housing is used to mount a load platform. The mover and stator of the voice coil actuator are respectively mounted on the intermediate platform 3 and the inner surface of the voice coil housing. The output force of the voice coil motor acts between the voice coil housing and the intermediate platform 3.

[0041] It should be noted that the stator of the voice coil actuator is mounted on the inner surface of the voice coil housing, and the mover of the voice coil actuator is mounted on the intermediate platform 3, or the mover of the voice coil actuator is mounted on the inner surface of the voice coil housing, and the stator of the voice coil actuator is mounted on the intermediate platform 3.

[0042] Furthermore, the base 6 has the same structure as the intermediate platform 3, and the structure of the base 6 is as follows: Figure 7 As shown.

[0043] In some embodiments, the flexible guide 2 includes a flexible hinge, one end of the flexible guide 2 is fixedly connected to the voice coil housing, and the other end of the flexible guide 2 is fixedly connected to the intermediate platform 3; one end of the rigid guide 4 is fixedly connected to the piezoelectric housing 51, and the other end of the rigid guide 4 is fixedly connected to the base 6.

[0044] Example 1 like Figure 9 As shown, this invention provides a three-degree-of-freedom vibration isolation system. The system includes an upper platform 8 (when the three-degree-of-freedom vibration isolation system is constructed using three dual-actuator vibration isolation devices, the three dual-actuator devices share the same load platform, referred to here as the upper platform 8), a lower platform 9, and a three-legged rigid guide mechanism 10 (i.e., a dual-actuator vibration isolation device). In each leg-mounted rigid guide mechanism 10, flexible guide members 2 and rigid guide members 4 are evenly distributed at 120° intervals along the circumference and are respectively connected to the corresponding component's housing and base 6, thereby providing low-stiffness guidance for the voice coil motor vibration isolation unit 1 and high-stiffness support for the piezoelectric ceramic vibration isolation unit 5. In the voice coil motor vibration isolation unit 1, the mover of the voice coil motor is fixed inside the voice coil housing, and the stator is fixed on the intermediate platform 3. In the piezoelectric ceramic vibration isolation unit 5, the top of the piezoelectric ceramic actuator engages with the piezoelectric housing 51 through an anti-torsion groove structure 7 to prevent torsion, and its bottom is fixed to the base 6 through a gasket. This structure achieves physical integration of a large-stroke, low-stiffness upper layer with a high-stiffness, high-precision lower layer support. This example employs a reconfigurable vibration isolation system consisting of two connected layers, one flexible and one rigid, utilizing its physical frequency domain separation characteristics to simultaneously meet the requirements of wide-frequency domain vibration isolation and high-stiffness support.

[0045] This invention defines the aforementioned integrated dual-actuated vibration isolation device as a standardized active actuator. Based on the principle of parallel mechanism topology, multiple sets of these actuators are arranged between the upper platform 8 and the lower platform 9 to construct a spatial support system. For a three-degree-of-freedom vibration isolation system, three dual-actuated vibration isolation devices are vertically mounted on a common base plate with their standardized bottom interfaces, and their tops are connected to a rigid platform. By coordinating the control of the three vibration isolation systems, three-dimensional translational vibration isolation of the load platform can be achieved.

[0046] Specifically, three dual-actuated vibration isolation devices are vertically installed between the common base and the load platform. Through coordinated control, each outrigger achieves vibration isolation, thus forming a stable platform with translational vibration isolation capabilities in the X, Y, and Z directions. Furthermore, following the Stewart platform configuration, six dual-actuated vibration isolation devices are installed at a specific spatial angle between the upper and lower platforms 9. The six dual-actuated vibration isolation devices share the same load platform. Each dual-actuated vibration isolation device acts as an intelligent active outrigger integrating sensing, actuation, and control. The central controller calculates the required extension and high-frequency compensation for each system based on the six-degree-of-freedom motion error. Through the kinematic calculation and coordinated control of the central controller, a fully active vibration isolation system capable of simultaneously suppressing vibrations in all six degrees of freedom can be constructed. Since the dynamic paths of the dual actuators within each dual-actuated vibration isolation device are decoupled, no additional harmful control coupling is introduced when multiple dual-actuated vibration isolation devices are spliced ​​together, making the system reconfiguration process quick, reliable, and with predictable performance. At the control level, a two-way mapping model from the local physical quantities of each leg to the overall attitude of the platform is constructed using the kinematic Jacobian matrix. This seamlessly extends the hierarchical collaborative strategy of "feedforward pre-isolation-position servo-ceiling damping" in the single-axis dimension to the multi-dimensional space. By globally decoupling and allocating the piezoelectric and voice coil actuation forces of each leg, precise locking of the six-degree-of-freedom attitude of the load platform and wideband omnidirectional vibration suppression are achieved.

[0047] like Figure 10 As shown, the present invention provides a vibration isolation control method for a dual-actuation vibration isolation device, which is implemented using a dual-actuation vibration isolation device, and specifically includes the following steps: S1: The dual-actuation vibration isolation device starts working. At time i, the first velocity sensor collects the disturbance velocity signal at the foundation, the second velocity sensor collects the first absolute motion velocity signal, and the third velocity sensor collects the second absolute motion velocity signal. S2: The feedforward control loop drives the piezoelectric ceramic actuator to generate a displacement opposite to the direction of the disturbance based on the disturbance velocity signal at the base. The displacement servo feedback control loop integrates the first absolute motion velocity signal and converts it into a displacement signal, driving the piezoelectric ceramic actuator to output the actuation displacement. S3: The speed feedback control loop drives the voice coil motor actuator to apply active damping based on the second absolute motion speed signal; S4: Replace time i with time i+1, and repeat steps S1-S3 until the dual-actuated vibration isolation device finishes working, thus completing the vibration isolation control of the dual-actuated vibration isolation device.

[0048] It should be noted that this invention proposes a composite hierarchical collaborative control strategy, achieving vibration isolation through three collaborative control paths. For the first-stage control of the piezoelectric ceramic actuator (PZT): this stage employs a composite mode with feedforward cancellation as the primary method and displacement servo as a secondary method. The feedforward control loop receives the signal from the first velocity sensor (VS1), generates a drive signal through a feedforward filter, and drives the piezoelectric ceramic actuator to produce a displacement opposite to the predicted disturbance direction, achieving proactive isolation of the foundation vibration. The displacement servo feedback control loop simultaneously receives the signal from the second velocity sensor (VS2), which is transmitted to a low-pass filter with integration function. This filter integrates the velocity signal within the effective frequency band to obtain the displacement information of the intermediate platform 3. A correction signal is generated through servo algorithms such as PID, finely adjusting the low-frequency residual vibration that is not completely canceled by the feedforward to maintain internal attitude stability. For the second-stage control of the voice coil actuator (VCM): this stage employs an absolute velocity feedback (ceiling damping) mode. The velocity feedback control loop receives signals from the third velocity sensor (VS3) and, based on the ceiling damping control law, drives the voice coil actuator to output a force proportional to the absolute velocity of the load, in the opposite direction. This strategy is physically equivalent to connecting a virtual damper between the load and the inertial space, effectively suppressing structural resonance peaks and attenuating mid-to-high frequency micro-amplitude vibrations. Therefore, in the physically connected dual-layer vibration isolation architecture, the lower-layer piezoelectric ceramic actuator and the upper-layer voice coil motor actuator form a frequency-domain decoupled, functionally complementary cooperative control mechanism. The lower-layer piezoelectric ceramic actuator is mainly used for feedforward isolation of foundation disturbances and servo adjustment of low-frequency attitude. The upper-layer voice coil motor actuator is mainly used to inject active damping into the dual-actuated vibration isolation device to suppress system resonance peaks. Both are controlled based on composite sensor information and control laws, forming a synergistic effect in different frequency bands, ultimately enabling the entire dual-actuated vibration isolation device to possess high-performance active vibration isolation capabilities across the entire frequency range from low to mid-to-high frequencies.

[0049] In some embodiments, the dynamic model of the feedforward control loop is: ; in, This is the feedforward control output signal. This is the feedforward control transfer function. Let be the transfer function of a first-order low-pass filter. This is for feedforward control of the output displacement of the piezoelectric ceramic actuator. For feedforward gain, The perturbation velocity signal at the base.

[0050] It should be noted that, in order to achieve better vibration isolation performance, feedforward control is introduced on the basis of feedback control. Vibration signals at 6 points on the base are directly collected, and an active displacement opposite to the vibration signal is output through a piezoelectric ceramic actuator, so as to achieve early response and suppression of vibration signals and synchronous cancellation of measurable disturbances.

[0051] In some embodiments, the dynamic model of the displacement servo feedback control loop is as follows: ; in, This is the output signal for displacement servo feedback control. This is the transfer function for displacement servo feedback control. Let be the transfer function of a first-order low-pass filter. The displacement is output by the piezoelectric ceramic actuator for displacement servo feedback control. For displacement servo feedback gain, For Laplace variables, This is the first absolute velocity signal.

[0052] It should be noted that the displacement servo feedback control loop determines the operating frequency band through a first-order low-pass filter and sets the cutoff frequency fc to 10 Hz. This value represents an optimal trade-off between balancing low-frequency vibration isolation performance and multi-loop decoupling: if fc is set too low, the effective control bandwidth will be excessively compressed, resulting in insufficient suppression of low-frequency vibrations in the critical 1-10 Hz frequency band; conversely, if fc is set too high, the displacement feedback frequency band will extend into the mid-to-high frequencies, causing frequency domain overlap and phase interference with the velocity feedback control loop. Therefore, the 10 Hz setting ensures both low-frequency vibration isolation performance and effectively cuts off coupling interference to the mid-to-high frequency control loop. After determining the operating frequency band, the velocity signal of the intermediate platform 3 is collected using a second velocity sensor and integrated to obtain the inertial displacement. Vibration isolation performance is improved by increasing the feedback gain. The feedback acts on the lower piezoelectric ceramic actuator, controlling its extension and retraction to achieve inertial stabilization of the intermediate mass level.

[0053] In some embodiments, the dynamic model of the velocity feedback control loop is: ; in, For speed feedback control output signal, For the velocity feedback transfer function, Here is the transfer function of the high-pass filter. For speed signal, For speed feedback gain, This is the second absolute velocity signal.

[0054] It should be noted that the speed feedback control loop, as the inner loop of the composite control system, aims to suppress the resonance peaks of the passive system by introducing active damping, thereby providing a stable controlled object for subsequent control loops. The speed feedback control loop uses the absolute speed of the load platform as the feedback signal. After being limited to the control frequency band by a first-order high-pass filter with a cutoff frequency of 100 Hz, a speed feedback gain is applied. Generate control force.

[0055] like Figure 11 As shown, the upper curve with resonance peaks is the vibration transmissibility curve of the system in a purely passive state; the lower curve is the vibration transmissibility curve of the system after applying the complete feedforward-feedback composite control strategy of this invention. Figure 11 As can be seen, after adopting the composite control strategy of the present invention, the vibration transmissibility of the dual-actuator vibration isolation device in the target frequency band is significantly reduced, the resonance peak is effectively suppressed, and the system's isolation capability against external vibration excitation is significantly enhanced. Simultaneously, the overall curve shifts downward and becomes flatter after control, indicating that the control strategy not only improves the vibration suppression effect near resonance but also enhances the overall vibration isolation performance over a wider frequency range.

[0056] It should be understood that the various forms of processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this invention disclosure can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution disclosed in this invention can be achieved, and this is not limited herein.

[0057] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A dual-actuation vibration isolation device, characterized in that: include: Two-stage actuation vibration isolation unit, signal acquisition module, and hierarchical collaborative control module; The dual-stage actuation vibration isolation unit includes a base, an intermediate platform, a load platform, a piezoelectric ceramic vibration isolation unit and a rigid guide connected in parallel between the base and the intermediate platform, and a voice coil motor vibration isolation unit and a flexible guide connected in parallel between the intermediate platform and the load platform. The signal acquisition module includes a first velocity sensor mounted on the base, a second velocity sensor mounted on the intermediate platform, and a third velocity sensor mounted on the load platform. Each sensor is used to acquire vibration signals at its respective location. The hierarchical collaborative control module includes a feedforward control loop, a displacement servo feedback control loop, and a velocity feedback control loop. The feedforward control loop is based on the acquisition results of the first velocity sensor, the displacement servo feedback control loop is based on the acquisition results of the second velocity sensor, and the velocity feedback control loop is based on the acquisition results of the third velocity sensor, to perform feedforward and feedback composite control on the two-stage actuation vibration isolation unit.

2. The dual-actuation vibration isolation device according to claim 1, characterized in that: The piezoelectric ceramic vibration isolation unit is connected to the base through no less than three rigid guide members; the voice coil motor vibration isolation unit is connected to the intermediate platform through no less than three flexible guide members.

3. The dual-actuation vibration isolation device according to claim 1, characterized in that: The piezoelectric ceramic vibration isolation unit includes a piezoelectric housing for mounting an intermediate platform, and a piezoelectric ceramic actuator disposed inside the piezoelectric housing. The actuation displacement of the piezoelectric ceramic actuator acts between the piezoelectric housing and the base.

4. The dual-actuation vibration isolation device according to claim 3, characterized in that: The voice coil motor vibration isolation unit includes a voice coil housing and a voice coil actuator disposed inside the voice coil housing. The voice coil housing is used to mount the load platform. The mover and stator of the voice coil actuator are respectively mounted on the intermediate platform and the inner surface of the voice coil housing. The output force of the voice coil motor acts between the voice coil housing and the intermediate platform.

5. The dual-actuation vibration isolation device according to claim 4, characterized in that: The flexible guide includes a flexible hinge, one end of which is fixedly connected to the voice coil housing, and the other end of which is fixedly connected to the intermediate platform. One end of the rigid guide is fixedly connected to the piezoelectric housing, and the other end of the rigid guide is fixedly connected to the base.

6. A vibration isolation control method for a dual-actuation vibration isolation device, implemented using the dual-actuation vibration isolation device as described in claim 1, characterized in that: Specifically, the steps include the following: S1: The dual-actuation vibration isolation device starts working. At time i, the first velocity sensor collects the disturbance velocity signal at the foundation, the second velocity sensor collects the first absolute motion velocity signal, and the third velocity sensor collects the second absolute motion velocity signal. S2: The feedforward control loop drives the piezoelectric ceramic actuator to generate a displacement opposite to the direction of the disturbance based on the disturbance velocity signal at the base. The displacement servo feedback control loop integrates the first absolute motion velocity signal and converts it into a displacement signal, driving the piezoelectric ceramic actuator to output the actuation displacement. S3: The speed feedback control loop drives the voice coil motor actuator to apply active damping based on the second absolute motion speed signal; S4: Replace time i with time i+1, and repeat steps S1-S3 until the dual-actuated vibration isolation device finishes working, thus completing the vibration isolation control of the dual-actuated vibration isolation device.

7. The vibration isolation control method of the dual-actuation vibration isolation device according to claim 6, characterized in that: The dynamic model of the feedforward control loop is as follows: ； in, This is the feedforward control output signal. This is the feedforward control transfer function. The transfer function of a first-order low-pass filter. This is for feedforward control of the output displacement of the piezoelectric ceramic actuator. For feedforward gain, The perturbation velocity signal at the base.

8. The vibration isolation control method of the dual-actuation vibration isolation device according to claim 6, characterized in that: The dynamic model of the displacement servo feedback control loop is as follows: ； in, This is the output signal for displacement servo feedback control. This is the transfer function for displacement servo feedback control. Let be the transfer function of a first-order low-pass filter. The displacement is output by the piezoelectric ceramic actuator for displacement servo feedback control. For displacement servo feedback gain, For Laplace variables, This is the first absolute velocity signal.

9. The vibration isolation control method of the dual-actuation vibration isolation device according to claim 6, characterized in that: The dynamic model of the speed feedback control loop is as follows: ； in, For speed feedback control output signal, For the velocity feedback transfer function, Here is the transfer function of the high-pass filter. For speed feedback signal, For speed feedback gain, This is the second absolute velocity signal.

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