{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T07:42:38Z","timestamp":1771054958737,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2023,9,26]],"date-time":"2023-09-26T00:00:00Z","timestamp":1695686400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key R&amp;D Program of China","award":["2020YFC2200100"],"award-info":[{"award-number":["2020YFC2200100"]}]},{"name":"National Key R&amp;D Program of China","award":["NML202302"],"award-info":[{"award-number":["NML202302"]}]},{"name":"CAS Key Laboratory of Microgravity","award":["2020YFC2200100"],"award-info":[{"award-number":["2020YFC2200100"]}]},{"name":"CAS Key Laboratory of Microgravity","award":["NML202302"],"award-info":[{"award-number":["NML202302"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In space gravitational wave detection missions, a drag-free system is used to keep the test mass (TM) free-falling in an ultralow-noise environment. Ground verification experiments should be carried out to clarify the shielding and compensating capabilities of the system for multiple stray force noises. A hybrid apparatus was designed and analyzed based on the traditional torsion pendulum, and a technique for enhancing the sensitivity of the torsion pendulum system by employing the differential wavefront sensing (DWS) optical readout was proposed. The readout resolution experiment was then carried out on an optical bench that was designed and established. The results indicate that the angular resolution of the DWS signal in optical readout mode can reach the level of 10 nrad\/Hz1\/2 over the full measurement band. Compared with the autocollimator, the sensitivity of the torsional pendulum is noticeably improved, and the background noise is expected to reach 4.5 \u00d7 10\u221215 Nm\/Hz1\/2@10 mHz. This method could also be applied to future upgrades of similar systems.<\/jats:p>","DOI":"10.3390\/s23198087","type":"journal-article","created":{"date-parts":[[2023,9,26]],"date-time":"2023-09-26T08:58:17Z","timestamp":1695718697000},"page":"8087","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Using DWS Optical Readout to Improve the Sensitivity of Torsion Pendulum"],"prefix":"10.3390","volume":"23","author":[{"given":"Shaoxin","family":"Wang","sequence":"first","affiliation":[{"name":"Center for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences (CAS), Beijing 100190, China"},{"name":"Taiji Laboratory for Gravitational Wave Universe (Beijing\/Hangzhou), University of Chinese Academy of Sciences (UCAS), Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Heshan","family":"Liu","sequence":"additional","affiliation":[{"name":"Center for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences (CAS), Beijing 100190, China"},{"name":"Taiji Laboratory for Gravitational Wave Universe (Beijing\/Hangzhou), University of Chinese Academy of Sciences (UCAS), Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lei","family":"Dai","sequence":"additional","affiliation":[{"name":"Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences (CAS), Changchun 130033, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ziren","family":"Luo","sequence":"additional","affiliation":[{"name":"Center for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences (CAS), Beijing 100190, China"},{"name":"Taiji Laboratory for Gravitational Wave Universe (Beijing\/Hangzhou), University of Chinese Academy of Sciences (UCAS), Beijing 100049, China"},{"name":"Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences (UCAS), Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3543-7777","authenticated-orcid":false,"given":"Peng","family":"Xu","sequence":"additional","affiliation":[{"name":"Center for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences (CAS), Beijing 100190, China"},{"name":"Taiji Laboratory for Gravitational Wave Universe (Beijing\/Hangzhou), University of Chinese Academy of Sciences (UCAS), Beijing 100049, China"},{"name":"Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences (UCAS), Hangzhou 310024, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pan","family":"Li","sequence":"additional","affiliation":[{"name":"Center for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences (CAS), Beijing 100190, China"},{"name":"Taiji Laboratory for Gravitational Wave Universe (Beijing\/Hangzhou), University of Chinese Academy of Sciences (UCAS), Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ruihong","family":"Gao","sequence":"additional","affiliation":[{"name":"Center for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences (CAS), Beijing 100190, China"},{"name":"Taiji Laboratory for Gravitational Wave Universe (Beijing\/Hangzhou), University of Chinese Academy of Sciences (UCAS), Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dayu","family":"Li","sequence":"additional","affiliation":[{"name":"Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences (CAS), Changchun 130033, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keqi","family":"Qi","sequence":"additional","affiliation":[{"name":"Center for Gravitational Wave Experiment, National Microgravity Laboratory, Institute of Mechanics, Chinese Academy of Sciences (CAS), Beijing 100190, China"},{"name":"Taiji Laboratory for Gravitational Wave Universe (Beijing\/Hangzhou), University of Chinese Academy of Sciences (UCAS), Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"131103","DOI":"10.1103\/PhysRevLett.116.131103","article-title":"GW150914: The Advanced LIGO detectors in the era of first discoveries","volume":"116","author":"Abbott","year":"2016","journal-title":"Phys. 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