{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T03:01:22Z","timestamp":1760151682878,"version":"build-2065373602"},"reference-count":39,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,4,11]],"date-time":"2022-04-11T00:00:00Z","timestamp":1649635200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001775","name":"University of Technology Sydney","doi-asserted-by":"publisher","award":["321720-2332076"],"award-info":[{"award-number":["321720-2332076"]}],"id":[{"id":"10.13039\/501100001775","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Double bounce is an unusual and potentially very hazardous phenomenon that most trampoline users may have experienced, yet few would have really understood how and why it occurs. This paper provides an in-depth investigation into the double bounce. Firstly, the static and dynamic characteristics of a recreational trampoline are analysed theoretically and verified through experiments. Then, based on the developed trampoline dynamic model, double bounce simulation is conducted with two medicine balls released with different time delays. Through simulation, the process of double bounce is presented in detail, which comprehensively reveals how energy is transferred between users during double bounce. Furthermore, the effect of release time delay on double bounce is also presented. Finally, we conducted an experiment which produced similar results to the simulation and validated the reliability of the trampoline dynamic model and double bounce theoretical analysis.<\/jats:p>","DOI":"10.3390\/s22082916","type":"journal-article","created":{"date-parts":[[2022,4,12]],"date-time":"2022-04-12T22:48:45Z","timestamp":1649803725000},"page":"2916","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Investigation into the Trampoline Dynamic Characteristics and Analysis of Double Bounce Vibrations"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1926-7867","authenticated-orcid":false,"given":"David","family":"Eager","sequence":"first","affiliation":[{"name":"Faculty of Engineering and Information Technology, University of Technology Sydney, Sydney 2007, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5070-141X","authenticated-orcid":false,"given":"Shilei","family":"Zhou","sequence":"additional","affiliation":[{"name":"Faculty of Engineering and Information Technology, University of Technology Sydney, Sydney 2007, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6215-3297","authenticated-orcid":false,"given":"Karlos","family":"Ishac","sequence":"additional","affiliation":[{"name":"Faculty of Engineering and Information Technology, University of Technology Sydney, Sydney 2007, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1246-3454","authenticated-orcid":false,"given":"Imam","family":"Hossain","sequence":"additional","affiliation":[{"name":"Faculty of Engineering and Information Technology, University of Technology Sydney, Sydney 2007, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5749-1299","authenticated-orcid":false,"given":"Adam","family":"Richards","sequence":"additional","affiliation":[{"name":"Mr Trampoline, 966 Dandenong Road, Melbourne 3163, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8977-6144","authenticated-orcid":false,"given":"Lisa N.","family":"Sharwood","sequence":"additional","affiliation":[{"name":"Faculty of Engineering and Information Technology, University of Technology Sydney, Sydney 2007, Australia"},{"name":"Faculty of Medicine and Health, University of Sydney, Sydney 2006, Australia"},{"name":"Faculty of Medicine and Health, University of New South Wales, Sydney 2032, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,11]]},"reference":[{"key":"ref_1","first-page":"43","article-title":"The effect of trampoline parks on presentations to the Christchurch Emergency Department","volume":"131","author":"Roffe","year":"2018","journal-title":"N. Z. Med. J."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"989","DOI":"10.3349\/ymj.2018.59.8.989","article-title":"Pediatric Trampoline-Related injuries in a nationwide registry in South Korea, 2011 to 2016","volume":"59","author":"Choi","year":"2018","journal-title":"Yonsei Med. J."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"82","DOI":"10.11622\/smedj.2019168","article-title":"A retrospective review of trampoline-related injuries presenting to a paediatric emergency department in Singapore","volume":"62","author":"Lim","year":"2021","journal-title":"Singap. Med. J."},{"key":"ref_4","first-page":"1","article-title":"Trampolines\u2014Facts and myths","volume":"23","author":"Eager","year":"2008","journal-title":"Kidsafe Play. News"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1080\/17461391.2020.1728390","article-title":"Developing a mathematical model to predict energy expenditure while bouncing on a trampoline","volume":"21","author":"Alexander","year":"2021","journal-title":"Eur. J. Sport Sci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"506","DOI":"10.1016\/j.archger.2014.08.009","article-title":"Effect of different types of exercise on postural balance in elderly women: A randomized controlled trial","volume":"59","author":"Dascal","year":"2014","journal-title":"Arch. Gerontol. Geriatr."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"3351","DOI":"10.1589\/jpts.27.3351","article-title":"The effect of modified trampoline training on balance, gait, and falls efficacy of stroke patientss","volume":"27","author":"Hahn","year":"2015","journal-title":"J. Phys. Ther. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2701","DOI":"10.1016\/j.ridd.2013.05.034","article-title":"Effects of a trampoline exercise intervention on motor performance and balance ability of children with intellectual disabilities","volume":"34","author":"Giagazoglou","year":"2013","journal-title":"Res. Dev. Disabil."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1123\/jab.29.5.628","article-title":"Analysis of energy flow during playground surface impacts","volume":"29","author":"Davidson","year":"2013","journal-title":"J. Appl. Biomech."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"371","DOI":"10.3390\/vibration3040025","article-title":"Jerk within the context of science and engineering\u2014A systematic review","volume":"3","author":"Hayati","year":"2020","journal-title":"Vibration"},{"key":"ref_11","first-page":"065012","article-title":"Velocity, acceleration, jerk, snap and vibration: Forces in our bodies during a roller coaster ride","volume":"55","author":"Pendrill","year":"2020","journal-title":"Eur. J. Phys."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Ishac, K., and Eager, D. (2021). Evaluating martial arts punching kinematics using a vision and inertial sensing system. Sensors, 21.","DOI":"10.3390\/s21061948"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"1802","DOI":"10.1089\/neu.2015.4208","article-title":"Mechanisms of head and neck injuries sustained by helmeted motorcyclists in fatal real world crashe\u2014Analysis of 47 in-depth cases","volume":"33","author":"Whyte","year":"2015","journal-title":"J. Neurotrauma"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"494","DOI":"10.1007\/s00167-012-1982-x","article-title":"Specific injuries induced by the practice of trampoline, tumbling and acrobatic gymnastics","volume":"21","author":"Grapton","year":"2013","journal-title":"Knee Surg. Sports Traumatol. Arthrosc."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Eager, D., Hayati, H., and Chapman, C. (2016, January 11\u201317). Impulse force as an additional safety criterion for improving the injury prevention performance of impact attenuation surfaces in children\u2019s playgrounds. Proceedings of the ASME International Mechanical Engineering Congress and Exposition, Phoenix, AZ, USA.","DOI":"10.1115\/IMECE2016-65565"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"011002","DOI":"10.1115\/1.4039999","article-title":"Additional injury prevention criteria for impact attenuation surfacing within children\u2019s playgrounds","volume":"5","author":"Eager","year":"2019","journal-title":"ASCE-ASME J. Risk Uncertain. Eng. Syst. Part B Mech. Eng."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"9","DOI":"10.5694\/mja18.00549","article-title":"Ensuring safety in public playgrounds: Everybody\u2019s business","volume":"210","author":"Barker","year":"2019","journal-title":"Med. J. Aust."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"577","DOI":"10.1111\/j.1440-1754.2012.02426.x","article-title":"Survey of injury sources for a trampoline with equipment hazards designed out","volume":"48","author":"Eager","year":"2012","journal-title":"J. Paediatr. Child Health"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1080\/17457300.2012.674041","article-title":"Injury survey of a non-traditional \u2018soft-edge\u2019 trampoline designed to lower equipment hazards","volume":"20","author":"Eager","year":"2013","journal-title":"Inj. Control Saf. Promot."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"185","DOI":"10.1136\/ip.2009.025494","article-title":"Effectiveness of pads and enclosures as safety interventions on consumer trampolines","volume":"16","author":"Alexander","year":"2010","journal-title":"Inj. Prev."},{"key":"ref_21","unstructured":"Eager, D., Nixon, J., and Chapman, C. (2007, January 15\u201317). Australian trampoline Standard\u2014Impact attenuation padding systems. Proceedings of the ABC6 Biomechanics, Auckland, New Zealand."},{"key":"ref_22","unstructured":"Eager, D., Chapman, C., and Davidson, P. (2011, January 7\u20139). Trampoline frame impact attenuation: Padded metal-frame vs soft-edge system. Proceedings of the IUTAM Symposium on Impact Biomechanics in Sport, Dublin, Ireland."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"491","DOI":"10.1111\/1753-6405.12404","article-title":"Australian trampoline injury patterns and trends","volume":"39","author":"Ashby","year":"2015","journal-title":"Aust. N. Z. J. Public Health"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1111\/1753-6405.12783","article-title":"Increasing injuries as trampoline parks expand within Australia: A call for mandatory standards","volume":"42","author":"Sharwood","year":"2018","journal-title":"Aust. N. Z. J. Public Health"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Hossain, I., Zhou, S., Ishac, K., Lind, E., Sharwood, L., and Eager, D. (2021). A Measurement of \u2018walking-the-wall\u2019 dynamics: An observational study using accelerometry and sensors to quantify risk associated with vertical wall impact attenuation in trampoline parks. Sensors, 21.","DOI":"10.3390\/s21217337"},{"key":"ref_26","unstructured":"Eager, D., Chapman, C., and Matotek, A. (2017, January 18\u201322). Double bounce vibration on trampolines and associated injuries. Proceedings of the 12th ICBEN Congress on Noise as a Public Health Problem, Zurich, Switzerland."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1136\/injuryprev-2015-041598","article-title":"Influence of voluntary standards and design modifications on trampoline injury in Victoria, Australia","volume":"21","author":"Ashby","year":"2015","journal-title":"Inj. Prev."},{"key":"ref_28","unstructured":"Routley, V. (2022, April 07). Trampoline Injuries. Available online: https:\/\/www.monash.edu\/__data\/assets\/pdf_file\/0018\/218430\/haz13.pdf."},{"key":"ref_29","unstructured":"(2015). Trampolines for Domestic Use\u2014Safety Aspects (Standard No. AS 4989:2015)."},{"key":"ref_30","unstructured":"Eager, D., Chapman, C., and Bondoc, K. (2012, January 9\u201312). Characterisation of trampoline bounce using acceleration. Proceedings of the 7th Australasian Congress on Applied Mechanics, Adelaide, Australia."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1088\/0031-9120\/50\/1\/64","article-title":"Free fall and harmonic oscillations: Analyzing trampoline jumps","volume":"50","author":"Pendrill","year":"2014","journal-title":"Phys. Educ."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"352","DOI":"10.1136\/injuryprev-2016-042071","article-title":"Paediatric injury from indoor trampoline centres","volume":"23","author":"Mulligan","year":"2017","journal-title":"Inj. Prev."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Kim, K.H., Kim, H.S., Kang, M.S., and Park, S.S. (2019). Varus shearing force is a main injury mechanism of pediatric trampoline-related injury in addition to compressive axial loading. PLoS ONE, 14.","DOI":"10.1371\/journal.pone.0217863"},{"key":"ref_34","unstructured":"du Soleil, C. (2022, April 07). The Life of the Artists. Available online: https:\/\/www.youtube.com\/watch?v=fzwmSwVVFfU."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"729","DOI":"10.1097\/BPO.0b013e318155ab1","article-title":"Pediatric trampoline injuries","volume":"27","author":"Hurson","year":"2007","journal-title":"J. Pediatr. Orthop."},{"key":"ref_36","unstructured":"Newsroom (2022, April 07). Maya\u2019s Story: Bouncing Back from a Serious Injury. Available online: https:\/\/www.acc.co.nz\/newsroom\/stories\/mayas-story\/."},{"key":"ref_37","unstructured":"Eager, D. (2018, January 7\u20139). Accelerometers used in the measurement of jerk, snap and crackle. Proceedings of the Australian Acoustical Society 2018 Annual Conference, Adelaide, Australia."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1088\/0143-0807\/37\/6\/065008","article-title":"Beyond velocity and acceleration: Jerk, snap and higher derivatives","volume":"37","author":"Eager","year":"2016","journal-title":"Eur. J. Phys."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s12283-021-00348-z","article-title":"Dynamic testing to determine and predict trampoline function","volume":"24","author":"Brown","year":"2021","journal-title":"Sports Eng."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/8\/2916\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T22:51:36Z","timestamp":1760136696000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/8\/2916"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,4,11]]},"references-count":39,"journal-issue":{"issue":"8","published-online":{"date-parts":[[2022,4]]}},"alternative-id":["s22082916"],"URL":"https:\/\/doi.org\/10.3390\/s22082916","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2022,4,11]]}}}