{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:46:36Z","timestamp":1760147196662,"version":"build-2065373602"},"reference-count":44,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,1,13]],"date-time":"2023-01-13T00:00:00Z","timestamp":1673568000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"internal Colorado School of Mines"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>This paper models an extensible catheter with an embedded magnet at its distal tip subject to an external magnetic field. We implement a control method coined observed control to perform model-based predictive control of the catheter using a Kalman smoother framework. Using this same smoother framework, we also solve for catheter shape and orientation given magnetic and insertion control using Cosserat rod theory and implement a disturbance observer for closed-loop control. We demonstrate observed control experimentally by traversing a 3D cube trajectory with the catheter tip. The catheter achieved positional accuracy of 3.3 mm average error in open-loop, while closed-loop control improved the accuracy to 0.33 mm.<\/jats:p>","DOI":"10.3390\/robotics12010011","type":"journal-article","created":{"date-parts":[[2023,1,16]],"date-time":"2023-01-16T01:31:15Z","timestamp":1673832675000},"page":"11","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Observed Control of Magnetic Continuum Devices"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1982-4993","authenticated-orcid":false,"given":"Richard L.","family":"Pratt","sequence":"first","affiliation":[{"name":"Mechanical Engineering Department, Colorado School of Mines, 1500 Illinois St, Golden, CO 80401, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1705-6671","authenticated-orcid":false,"given":"Brooke E.","family":"Suesser","sequence":"additional","affiliation":[{"name":"Mechanical Engineering Department, Colorado School of Mines, 1500 Illinois St, Golden, CO 80401, USA"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2070-4227","authenticated-orcid":false,"given":"Andrew J.","family":"Petruska","sequence":"additional","affiliation":[{"name":"Mechanical Engineering Department, Colorado School of Mines, 1500 Illinois St, Golden, CO 80401, USA"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1887","DOI":"10.1002\/lary.24566","article-title":"A novel computerized surgeon\u2013machine interface for robot-assisted laser phonomicrosurgery","volume":"124","author":"Mattos","year":"2014","journal-title":"Laryngoscope"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"505","DOI":"10.1109\/TMECH.2019.2893166","article-title":"Vision-Based 3-D Control of Magnetically Actuated Catheter Using BigMag\u2014An Array of Mobile Electromagnetic Coils","volume":"24","author":"Sikorski","year":"2019","journal-title":"IEEE\/ASME Trans. 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