Yip, Michael C.Yuen, Shelten G.Howe, Robert2011-06-092010Yip, Michael C., Shelten G. Yuen, and Robert D. Howe. 2010. A robust uniaxial force sensor for minimally invasive surgery. IEEE Transactions on Biomedical Engineering Bme 57(5): 1008-11.0018-9294http://nrs.harvard.edu/urn-3:HUL.InstRepos:4908615This paper presents a novel, miniature uniaxial force sensor for use within a beating heart during mitral valve annuloplasty. The sensor measures 5.5 mm in diameter and 12 mm in length, and provides a hollow core to pass instrumentation. A soft elastomer flexure design maintains a waterproof seal. Fiber optic transduction eliminates electrical circuitry within the heart, and acetal components minimize ultrasound imaging artifacts. Calibration uses a nonlinear, viscoelastic method, and in vitro tests demonstrate a 0 to 4 N force range with RMS errors of 0.13 N (<3.2%). In vivo tests provide the first endocardial measurements of tissue-MIS instrument interaction forces in a beating heart.en-USminimally invasive surgeryoptical force sensorbeating heart surgeryforce feedbackmitral valve annuloplastyJournal Article10.1109/TBME.2009.2039570