Tape Cast Multilayer Sonar Transducer Array
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional sonar transducer technologies are inefficient for large-scale array applications due to high production and maintenance costs, unreliable design, and difficulty in achieving accurate beamforming and shaping due to dimensional instability and impedance control issues, especially in conformal acoustic arrays for undersea sonar applications.
Innovation Solution
A tape cast ceramic one-piece multi-layer piezoelectric stack transducer array that conforms to ship hulls, allowing for electronically scanned beams without individualized tuning circuits, using a signal switching distribution network and processor to combine return signals, and leveraging advanced materials for high-power transduction at low voltages.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional tonpilz configuration technology is used, then transducers can be assembled using conventional manufacturing processes, but production and maintenance costs are high and reliability is low
Solution Approach 1:
The piezoelectric element is divided into multiple layers with different materials (PZT and PMN-PT) stacked in sequence, each layer serving specific functional requirements. This segmentation allows optimization of each layer's properties while maintaining overall transducer performance and reliability.
Solution Approach 2:
The patent employs composite piezoelectric materials consisting of PZT and PMN-PT layers with different piezoelectric coefficients. This composite structure enables simultaneous achievement of high coupling efficiency and controlled impedance characteristics, improving both reliability and performance.
2Ease of manufacture
If conventional tonpilz configuration with cemented joints is used, then assembly is simplified, but electrode coupling is not achieved and impedance control is difficult
Solution Approach 1:
The patent merges the piezoelectric element structure with the electrode coupling mechanism by integrating finger electrodes directly into the layered piezoelectric structure. This eliminates the need for separate cemented joints while achieving both mechanical bonding and electrical coupling.
Solution Approach 2:
The finger electrodes serve as an intermediary structure that mechanically connects adjacent piezoelectric elements while simultaneously providing electrical coupling. This intermediary mechanism achieves both structural integrity and impedance control without requiring separate cementing and electrical connection steps.
3Manufacturing precision
If conventional technology with individualized transformers/tuning circuits is used, then impedance matching can be achieved, but device complexity and production costs increase significantly
Solution Approach 1:
The patent designs the piezoelectric elements with standardized dimensions and electrode configurations that inherently provide matched impedance characteristics. This universal design allows all elements in the array to operate without individualized tuning circuits, reducing system complexity while maintaining impedance matching accuracy.
Solution Approach 2:
The patent controls the impedance characteristics by adjusting the physical parameters of the piezoelectric elements, specifically the thickness and material composition of each layer. By changing these parameters during manufacturing, the elements achieve desired impedance values without requiring post-assembly tuning circuits.
4Productivity
If large-scale arrays with thousands of transducers are constructed, then sonar capabilities are enhanced, but production costs and maintenance requirements increase
Solution Approach 1:
The sonar array is segmented into modular panels, each containing multiple transducer elements. This modular segmentation allows for standardized mass production of individual panels that can be assembled into large-scale arrays, reducing overall production costs and simplifying maintenance by allowing replacement of individual modules.
Solution Approach 2:
The patent optimizes the piezoelectric element parameters to achieve high performance at reduced cost by utilizing commercially available PZT and PMN-PT materials with standardized properties, eliminating the need for expensive custom-material fabrication while maintaining high sonar array capability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The tape cast ceramic sonar transducer array reduces production costs, improves electromechanical coupling efficiency, and maintains beam accuracy across varying hull curvatures, enabling efficient and reliable large-scale conformal sonar array operations with low voltage high electric field capabilities.
Implementation Method 1
a first piezoelectric ceramic layer comprising lead zirconate titanate (PZT) and having a first piezoelectric coefficient and a second piezoelectric ceramic layer comprising lead magnesium niobate-lead titanate (PMN-PT) and having a second piezoelectric coefficient
Data Source
AI summary
A tape cast transducer element assembly comprises a tape cast transducer element including a multi-layer piezoelectric stack diced from a sintered piezoelectric body formed from a plurality of thin film tape layers, the film thin tape layers sintered to produce a final density. A conductive film coats select ones of the thin film tape layers such that conductive layers of different polarities are exposed on opposing sides of the multi-layer piezoelectric stack. Electrodes are coupled to the conductive layers. Electrical leads are coupled to each electrode. A head mass is configured to encapsulate a top portion of the stack. A tail mass is configured to encapsulate a bottom portion of the stack. At least one coupling arrangement extends from a top surface of the head mass through the cross-sectional area of the head mass into the tail mass such that the stack is contained in a rigid assembly under compression.