{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T08:07:13Z","timestamp":1790842033691,"version":"4.1.0"},"reference-count":36,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2020,9,19]],"date-time":"2020-09-19T00:00:00Z","timestamp":1600473600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Aperiodic sparse 2D ultrasonic array configurations, including random array, log spiral array, and sunflower array, have been considered for their potential as conformable transducers able to image within a focal range of 30\u201380 mm, at an operating frequency of 2 MHz. Optimisation of the imaging performance of potential array patterns has been undertaken based on their simulated far field directivity functions. Two evaluation criteria, peak sidelobe level (PSL) and integrated sidelobe ratio (ISLR), are used to access the performance of each array configuration. Subsequently, a log spiral array pattern with \u221219.33 dB PSL and 2.71 dB ISLR has been selected as the overall optimal design. Two prototype transducers with the selected log spiral array pattern have been fabricated and characterised, one using a fibre composite element composite array transducer (CECAT) structure, the other using a conventional 1\u20133 composite (C1\u20133) structure. The CECAT device demonstrates improved coupling coefficient (0.64 to 0.59), reduced mechanical cross-talk between neighbouring array elements (by 10 dB) and improved operational bandwidth (by 16.5%), while the C1\u20133 device performs better in terms of sensitivity (~50%). Image processing algorithms, such as Hough transform and morphological opening, have been implemented to automatically detect and dimension particles located within a fluid-filled tube structure, in a variety of experimental scenarios, including bespoke phantoms using tissue mimicking material. Experiments using the fabricated CECAT log spiral 2D array transducer demonstrated that this algorithmic approach was able to detect the walls of the tube structure and stationary anomalies within the tube with a precision of ~0.1 mm.<\/jats:p>","DOI":"10.3390\/s20185370","type":"journal-article","created":{"date-parts":[[2020,9,19]],"date-time":"2020-09-19T07:06:09Z","timestamp":1600499169000},"page":"5370","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Design of 2D Sparse Array Transducers for Anomaly Detection in Medical Phantoms"],"prefix":"10.3390","volume":"20","author":[{"given":"Xiaotong","family":"Li","sequence":"first","affiliation":[{"name":"Department of Electronic and Electrical Engineering, University of Strathclyde, Glasgow G1 1XW, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anthony","family":"Gachagan","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, University of Strathclyde, Glasgow G1 1XW, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul","family":"Murray","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, University of Strathclyde, Glasgow G1 1XW, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1161\/STROKEAHA.115.009171","article-title":"Comparing Vessel Imaging Noncontrast Computed Tomography\/Computed Tomographic Angiography Should Be the New Minimum Standard in Acute Disabling Stroke","volume":"47","author":"Demchuk","year":"2016","journal-title":"Stroke"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1179","DOI":"10.1148\/rg.294085199","article-title":"US Artifacts","volume":"29","author":"Feldman","year":"2009","journal-title":"RadioGraphics"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"420","DOI":"10.1016\/j.nurt.2007.05.012","article-title":"Ultrasound-enhanced thrombolysis in acute ischemic stroke: Potential, failures, and safety","volume":"4","author":"Tsivgoulis","year":"2007","journal-title":"Neurotherapeutics"},{"key":"ref_4","unstructured":"Steinberg, B. 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