{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T12:42:09Z","timestamp":1791117729196,"version":"4.1.0"},"reference-count":38,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,29]],"date-time":"2026-08-29T00:00:00Z","timestamp":1787961600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007446","name":"Deanship of Research and Graduate Studies at King Khalid University","doi-asserted-by":"publisher","award":["RGP. 2\/236\/46"],"award-info":[{"award-number":["RGP. 2\/236\/46"]}],"id":[{"id":"10.13039\/501100007446","id-type":"DOI","asserted-by":"publisher"}]},{"award":["RGP. 2\/236\/46"],"award-info":[{"award-number":["RGP. 2\/236\/46"]}],"id":[{"id":"https:\/\/ror.org\/052kwzs30","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>In planar compliant mechanisms, single-input dual-output (SIDO) displacement amplifiers driven by piezoelectric actuators are frequently used in precision positioning, micro\/nano manipulation, and biomedical microdevices. Accurate experimental verification of these mechanisms remains challenging because traditional contact sensors can add excess stiffness and impact the structure\u2019s normal behavior, and single-axis interferometers cannot measure multiple points simultaneously. In contrast, 2D vision-based measurement offers a non-contact alternative capable of capturing full planar motion and synchronized displacement tracking within a single image frame. This paper reviews the literature on camera calibration, homography-based planar reconstruction, sub-pixel edge extraction, vision-based characterization of compliant mechanisms, and benchmarking of vision systems against laser interferometers and coordinate measuring machines (CMMs). In the review, the SIDO-CDAM developed by Ozarkar et al. based on the Instantaneous Center Building Block (IC-BB) approach has been chosen as the target characterization system. The reviewed studies confirm that the major technical components needed for a high-precision 2D vision framework have been independently validated. However, there seems to be a lack of an integrated framework designed for synchronized dual-output SIDO-CDAM characterization. To overcome this gap, a seven-layer 2D vision-based characterization framework is proposed for scalable inspection of prototype-scale and MEMS-scale compliant mechanisms.<\/jats:p>","DOI":"10.3390\/mi17091031","type":"journal-article","created":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T02:08:58Z","timestamp":1788142138000},"page":"1031","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Two-Dimensional, Vision-Based Measurement for Experimental Characterization of Planar Compliant Mechanisms: A Critical Review and Uncertainty-Aware Framework"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5953-2368","authenticated-orcid":false,"given":"Rohan R.","family":"Ozarkar","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, R. C. Patel Institute of Technology, Shirpur 425405, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nilesh P.","family":"Salunke","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, SVKM\u2019s NMIMS Global University, Dhule 424001, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Prajitsen G.","family":"Damle","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, Shram Sadhna Bombay Trust\u2019s College of Engineering and Technology, Jalgaon 425001, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shakeelur","family":"Raheman","sequence":"additional","affiliation":[{"name":"Department of Applied Science and Humanity, SVKM\u2019s NMIMS Global University, Dhule 424001, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6440-3170","authenticated-orcid":false,"given":"Khursheed B.","family":"Ansari","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, College of Engineering, King Khalid University, Abha 61421, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ozarkar, R.R., Salunke, N.P., Damle, P.G., Shukla, R., Raheman, S., and Ansari, K.B. 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