CN-122021315-A - Mixed optimization reverse design method and system for SAW angular velocity sensor

CN122021315ACN 122021315 ACN122021315 ACN 122021315ACN-122021315-A

Abstract

The invention belongs to the technical field of micro-electro-mechanical systems and sensors, and provides a SAW angular velocity sensor hybrid optimization reverse design method and system, wherein the method comprises the steps of determining an optimization object; the method comprises the steps of determining structural parameters of an interdigital transducer, defining a design space for each structural parameter, determining performance indexes corresponding to the structural parameters, including sensitivity and insertion loss, constructing a forward data set comprising a structural parameter set and a performance index set, establishing a nonlinear mapping relation between the structural parameter set and the performance index set, performing global search of the design space by adopting a genetic algorithm, screening candidate structural parameter solution sets, performing gradient descent optimization based on a numerical disturbance method on each solution in the candidate structural parameter solution sets in parallel, and performing iterative update along the gradient direction of the performance index to obtain the structural parameters meeting the optimal performance index. The invention solves the problems of low efficiency and difficult multi-target balance related to the traditional SAW angular velocity sensor.

Inventors

SHAO XIUTING
LU ZHILE

Assignees

山东师范大学

Dates

Publication Date: 20260512
Application Date: 20260130

Claims (10)

1. The SAW angular velocity sensor hybrid optimization reverse design method is characterized by comprising the following steps: Determining an optimized object, wherein the optimized object is an interdigital transducer in a SAW angular velocity sensor; Determining structural parameters of the interdigital transducer and defining a design space for each structural parameter, wherein the structural parameters comprise finger width, finger spacing, finger logarithm, electrode thickness and aperture; determining performance indexes corresponding to the structural parameters, including sensitivity and insertion loss; Constructing a forward data set comprising a structure parameter set and a performance index set, and establishing a nonlinear mapping relation between the structure parameter set and the performance index set; Carrying out global search of a design space by adopting a genetic algorithm and screening out candidate structure parameter solution sets; And carrying out gradient descent optimization based on a numerical disturbance method on each solution in the candidate structural parameter solution set in parallel, and carrying out iterative updating along the gradient direction of the performance index to obtain the structural parameter which meets the optimal performance index.
2. The SAW angular velocity sensor hybrid optimization reverse design method of claim 1, wherein the forward data set construction process comprises generating sample points in a design space by using a Latin hypercube sampling strategy, extracting performance index true values by using a finite element simulation method, summarizing simulation results, and eliminating non-converged sample points to form a finite element data set.
3. A SAW angular velocity sensor hybrid optimization reverse design method as in claim 2, wherein the finite element simulation method comprises the steps of reading sample points through finite element software, inputting parameter values in the sample points into a parameterized finite element model, and calling a finite element solver to complete calculation.
4. The hybrid optimal reverse design method for SAW angular velocity sensor as in claim 1, wherein the genetic algorithm adopts adaptive non-uniform mutation operator in the evolution process, and the new parameters generated after mutation The calculation formula of (2) is as follows: Wherein, the The j-th parameter value of the current individual is the old value before mutation; the new value is the new value after mutation, and the new parameter value is generated after mutation operation; random numbers uniformly distributed for [ -1, 1]; For a range of gene values, i.e. parameters The difference between the maximum possible value and the minimum possible value; Algebra for the current iteration; the method comprises the steps of presetting the total operation times of an algorithm for the maximum iteration algebra; is an attenuation factor; For system parameters, the constant of the shape of the attenuation curve is determined and taken =2 Or =3。
5. A SAW angular velocity sensor hybrid optimization reverse design method according to claim 1, wherein said numerical perturbation method comprises: By applying small perturbation steps Calculating an approximate gradient of the performance index with respect to the structural parameter: the parameter updating formula in the gradient descent iteration process is as follows: Wherein, the And The post-update and pre-update parameter vectors respectively, In order for the rate of learning to be high, And The weight coefficients of sensitivity and insertion loss, respectively.
6. A SAW angular velocity sensor hybrid optimization reverse design method according to claim 1, wherein after each iterative update, the system automatically performs constraint checking based on physical mechanism and process limits to correct structural parameters beyond reasonable limits.
7. The hybrid optimal reverse design method of a SAW angular velocity sensor according to claim 1, wherein the optimal performance index is a trade-off and optimization between sensitivity and insertion loss performance index to maximize the overall performance of the SAW angular velocity sensor.
8. A SAW angular velocity sensor hybrid optimization reverse design system, comprising: a first determination module configured to determine an optimization object, the optimization object being an interdigital transducer in a SAW angular velocity sensor; a second determination module configured to determine structural parameters of the interdigital transducer and define a design space for each structural parameter, the structural parameters including finger width, finger pitch, finger logarithm, electrode thickness, and aperture; A third determination module configured to determine performance metrics, including sensitivity and insertion loss, corresponding to the structural parameters; The data set construction module is configured to construct a forward data set comprising a structure parameter set and a performance index set, and establish a nonlinear mapping relation between the structure parameter set and the performance index set; The global optimizing module is configured to perform global search of a design space by adopting a genetic algorithm and screen out a candidate structure parameter solution set; and the local optimization module is configured to execute gradient descent optimization based on a numerical perturbation method on each solution in the candidate structural parameter solution set in parallel, and update the solution in an iterative manner along the gradient direction of the performance index to obtain the structural parameter which meets the optimal performance index.
9. A computer readable storage medium having a program stored thereon, which when executed by a processor, implements the steps of a SAW angular velocity sensor hybrid optimization reverse design method according to any one of claims 1-7.
10. An electronic device comprising a memory, a processor and a program stored on the memory and executable on the processor, wherein the processor performs the steps in a SAW angular velocity sensor hybrid optimization reverse design method as claimed in any one of claims 1-7 when the program is executed.

Description

Mixed optimization reverse design method and system for SAW angular velocity sensor Technical Field The invention belongs to the technical field of micro-electromechanical systems and sensors, and particularly relates to a SAW angular velocity sensor hybrid optimization reverse design method and system. Background The statements in this section merely provide background information related to the present disclosure and may not necessarily constitute prior art. The angular rate sensor is a core component in the fields of modern inertial navigation, attitude control, platform stabilization and the like. Compared with Mechanical gyroscopes and optical gyroscopes, MEMS (Micro-Electro-Mechanical-Systems) angular rate sensors are widely used due to their advantages of small size, light weight, low cost, high reliability, etc. A Surface Acoustic Wave (SAW) angular rate sensor, which is one of MEMS angular rate sensors, operates on a principle that does not depend on a vibrating mass but senses coriolis force using acoustic waves propagating on the surface of a piezoelectric substrate. When the substrate rotates, the coriolis force acting on the particles in the propagation path of the acoustic wave perturbs the propagation characteristics (wave velocity, amplitude, etc.) of the acoustic wave, and the angular velocity can be calculated by detecting such perturbation. In a surface acoustic wave angular rate sensor, there are two main modes of operation, standing wave mode and traveling wave mode. The standing wave mode is formed between the reflective gratings, the antinode and node positions of the standing wave mode are fixed, the response to the coriolis force is relatively direct, but the standing wave mode is easily influenced by the environmental temperature fluctuation and the substrate stress, and the stability is poor. The traveling wave mode is a surface acoustic wave excited by an transmit IDT (interdigital transducer), propagates a distance on the surface of the substrate, and is detected by a receive IDT. It realizes high sensitivity response to surface load by detecting phase shift or attenuation change of sound wave caused by the object to be measured on the propagation path. Therefore, the traveling wave mode is considered to be a preferred solution for realizing a high performance SAW angular rate sensor. As a core of the acoustic-electric conversion, the type of IDT directly determines the excitation efficiency of the acoustic wave and the fundamental frequency characteristics of the sensor. However, IDT design of the conventional saw angular rate sensor mainly relies on an empirical formula and a manually adjusted forward design method, and has the following inherent drawbacks: (1) The design efficiency is low, the design period is long depending on experience theory, and the best performance can not be ensured. (2) The multi-objective balance difficulty is that the quantitative relation research of the interaction of the Coriolis force and the surface acoustic wave is insufficient, and under the mutual restriction of key performance indexes, the optimal balance point of the sensitivity and the insertion loss is difficult to find, and the optimal balance cannot be realized. Disclosure of Invention In order to overcome the defects of the prior art, the invention provides a hybrid optimization reverse design method and a system for a SAW angular velocity sensor, which are used for converting a forward mode of a design flow from 'parameter to performance' into a reverse mode from 'target performance to optimal parameter', taking the maximum sensitivity and the minimum insertion loss as design targets, taking the structural parameter of an IDT as a design variable, and solving the problems of low efficiency and difficult multi-target balance related to the traditional SAW angular velocity sensor through hybrid optimization of a genetic algorithm and a gradient descent algorithm. To achieve the above object, one or more embodiments of the present invention provide the following technical solutions: The first aspect of the invention provides a hybrid optimized reverse design method of a SAW angular velocity sensor, comprising the following steps: Determining an optimized object, wherein the optimized object is an interdigital transducer in a SAW angular velocity sensor; Determining structural parameters of the interdigital transducer and defining a design space for each structural parameter, wherein the structural parameters comprise finger width, finger spacing, finger logarithm, electrode thickness and aperture; determining performance indexes corresponding to the structural parameters, including sensitivity and insertion loss; Constructing a forward data set comprising a structure parameter set and a performance index set, and establishing a nonlinear mapping relation between the structure parameter set and the performance index set; Carrying out global search of a design space by adopting a genetic