Towards the Automated Design of Phased Array Ultrasonic Transducers - Using Particle Swarms to Find "Smart" Start Points

Continuum Probe Designer by Acoustic Ideas Inc. is a tool that can help design the “best” phased array ultrasonic transducer for a given inspection task. Given a specific surface geometry for the ultrasonic transducer, one component of Continuum Probe Designer can determine the number of elements, and the required size and shape of each element to meet a list of ultrasonic inspection goals. Using the number of elements as a cost function, an optimization problem to find the best surface geometry for the transducer is created. Previous work has demonstrated that a (1+λ)-evolution strategy (ES) can be a very effective search technique for this problem. The performance of this ES was improved by starting it from “smart” (i.e. better than random) start points. Particle swarm optimization (PSO) can be used to improve the “smart” start points, and the overall PSO-ES hybrid is capable of finding feasible transducer designs from all of the start points in a benchmark test suite. This level of performance is an important step towards the use of Continuum Probe Designer as a fully automated tool for the design of phased array ultrasonic transducers.