{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T07:42:15Z","timestamp":1768462935499,"version":"3.49.0"},"reference-count":24,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2012,8,29]],"date-time":"2012-08-29T00:00:00Z","timestamp":1346198400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Baseball and softball pitch types are distinguished by the path and speed of the ball which, in turn, are determined by the angular velocity of the ball and the velocity of the ball center at the instant of release from the pitcher\u2019s hand. While radar guns and video-based motion capture (mocap) resolve ball speed, they provide little information about how the angular velocity of the ball and the velocity of the ball center develop and change during the throwing motion. Moreover, mocap requires measurements in a controlled lab environment and by a skilled technician. This study addresses these shortcomings by introducing a highly miniaturized, wireless inertial measurement unit (IMU) that is embedded in both baseballs and softballs. The resulting \u201cball-embedded\u201d sensor resolves ball dynamics right on the field of play. Experimental results from ten pitches, five thrown by one softball pitcher and five by one baseball pitcher, demonstrate that this sensor technology can deduce the magnitude and direction of the ball\u2019s velocity at release to within 4.6% of measurements made using standard mocap. Moreover, the IMU directly measures the angular velocity of the ball, which further enables the analysis of different pitch types.<\/jats:p>","DOI":"10.3390\/s120911933","type":"journal-article","created":{"date-parts":[[2012,8,29]],"date-time":"2012-08-29T11:47:52Z","timestamp":1346240872000},"page":"11933-11945","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":41,"title":["A Highly Miniaturized, Wireless Inertial Measurement Unit for Characterizing the Dynamics of Pitched Baseballs and Softballs"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8396-6967","authenticated-orcid":false,"given":"Ryan S.","family":"McGinnis","sequence":"first","affiliation":[{"name":"Mechanical Engineering, University of Michigan, 2350 Hayward St., Ann Arbor, MI 48105, USA"}]},{"given":"Noel C.","family":"Perkins","sequence":"additional","affiliation":[{"name":"Mechanical Engineering, University of Michigan, 2350 Hayward St., Ann Arbor, MI 48105, USA"}]}],"member":"1968","published-online":{"date-parts":[[2012,8,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1123\/jab.17.1.63","article-title":"Identification of release conditions and aerodynamic forces in pitched-baseball trajectories","volume":"17","author":"Alaways","year":"2001","journal-title":"J. Appl. Biomech."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1080\/02640410152006126","article-title":"Experimental determination of baseball spin and lift","volume":"19","author":"Alaways","year":"2001","journal-title":"J. Sports Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1119\/1.2805242","article-title":"The effect of spin on the flight of a baseball","volume":"76","author":"Nathan","year":"2008","journal-title":"Am. J. Phys."},{"key":"ref_4","first-page":"1","article-title":"Baseball throwing mechanics as they relate to pathology and performance\u2014A review","volume":"6","author":"Whitely","year":"2007","journal-title":"J. Sports Sci. Med."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1001","DOI":"10.1016\/j.compbiomed.2006.06.007","article-title":"Describing baseball pitch movement with right-hand rules","volume":"37","author":"Bahill","year":"2007","journal-title":"Comput. Biol. Med."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Theobalt, C., Albrecht, I., Haber, J., Magnor, M., and Seidel, H.-P. (2004, January 8\u201312). Pitching a Baseball: Tracking High-Speed Motion with Multi-Exposure Images. Los Angeles, CA, USA.","DOI":"10.1145\/1186562.1015758"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1371","DOI":"10.1016\/S0021-9290(99)00127-X","article-title":"Kinematic and kinetic comparison of baseball pitching among various levels of development","volume":"32","author":"Fleisig","year":"1999","journal-title":"J. Biomech."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"235","DOI":"10.1123\/ijsb.2.4.235","article-title":"Dynamics of the shoulder and elbow joints of the throwing arm during a baseball pitch","volume":"2","author":"Feltner","year":"1986","journal-title":"Int. J. Sport Biomech."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"597","DOI":"10.1177\/0363546505281796","article-title":"Kinematics and Kinetics of Elite Windmill Softball Pitching","volume":"34","author":"Werner","year":"2006","journal-title":"Am. J. Sports Med."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"552","DOI":"10.1177\/0363546504269253","article-title":"Biomechanics of youth windmill softball pitching","volume":"33","author":"Werner","year":"2005","journal-title":"Am. J. Sports Med."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"405","DOI":"10.2519\/jospt.1998.28.6.405","article-title":"Biomechanics of windmill softball pitching with implications about injury mechanisms at the shoulder and elbow","volume":"28","author":"Barrentine","year":"1998","journal-title":"J. Orthop. Sports Phys. Ther."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Lapinski, M., Berkson, E., Gill, T., Reinold, M., and Paradiso, J.A. (2009, January 4\u20137). A Distributed Wearable, Wireless Sensor System for Evaluating Professional Baseball Pitchers and Batters. Linz, Austria.","DOI":"10.1109\/ISWC.2009.27"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1299\/jamdsm.4.167","article-title":"3D measurement of forearm and upper arm during throwing motion using body mounted sensor","volume":"4","author":"Koda","year":"2010","journal-title":"J. Adv. Mech. Des. Syst. Manuf."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1007\/s12283-010-0054-z","article-title":"Bowling ball dynamics revealed by miniature wireless MEMS inertial measurement unit","volume":"13","author":"King","year":"2010","journal-title":"Sports Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1007\/s12283-012-0084-9","article-title":"A new technology for resolving the dynamics of a swinging bat","volume":"15","author":"King","year":"2012","journal-title":"Sports Eng."},{"key":"ref_16","unstructured":"King, K.W. (2008). The Design and Application of Wireless MEMS Inertial Measurement Units for the Measurement and Analysis of Golf Swings, University of Michigan."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"619","DOI":"10.1016\/j.sna.2007.08.028","article-title":"Wireless MEMS inertial sensor system for golf swing dynamics","volume":"141","author":"King","year":"2008","journal-title":"Sens. Actuators A Phys."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"580","DOI":"10.1016\/j.proeng.2012.04.099","article-title":"Pitcher training aided by instrumented baseball","volume":"34","author":"McGinnis","year":"2012","journal-title":"Proced. Eng."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"041013:1","DOI":"10.1115\/1.4006162","article-title":"Reconstructing free-flight angular velocity from miniaturized wireless accelerometer","volume":"79","author":"McGinnis","year":"2012","journal-title":"J. Appl. Mech."},{"key":"ref_20","unstructured":"Verducci, T. How a Danish tech company is revolutionizing pitching data. Available online: http:\/\/sportsillustrated.cnn.com\/2011\/writers\/tom_verducci\/04\/12\/fastballs.trackman\/index.html (accessed on 28 August 2012)."},{"key":"ref_21","unstructured":"Greenwood, D.T. (1965). Principles of Dynamics, Prentice-Hall."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1431","DOI":"10.1002\/nme.1620380903","article-title":"Non-linear dynamics of three-dimensional rods: Exact energy and momentum conserving algorithms","volume":"38","author":"Simo","year":"1995","journal-title":"Int. J. Numer. Methods Eng."},{"key":"ref_23","unstructured":"Savage, P. (2000). Strapdown Analytics, Strapdown Associates."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Titterton, D.H., and Weston, J.L. (2004). Strapdown Inertial Navigation Technology, Institution of Electrical Engineers.","DOI":"10.1049\/PBRA017E"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/9\/11933\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:52:03Z","timestamp":1760219523000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/9\/11933"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,8,29]]},"references-count":24,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2012,9]]}},"alternative-id":["s120911933"],"URL":"https:\/\/doi.org\/10.3390\/s120911933","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,8,29]]}}}