{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T02:00:44Z","timestamp":1773885644099,"version":"3.50.1"},"reference-count":64,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2021,4,30]],"date-time":"2021-04-30T00:00:00Z","timestamp":1619740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"F\u00e9d\u00e9ration des Amput\u00e9s de Guerre de France","award":["N\/A"],"award-info":[{"award-number":["N\/A"]}]},{"name":"Universit\u00e9 Franco-Italienne","award":["C2-881"],"award-info":[{"award-number":["C2-881"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The analysis of the body center of mass (BCoM) 3D kinematics provides insights on crucial aspects of locomotion, especially in populations with gait impairment such as people with amputation. In this paper, a wearable framework based on the use of different magneto-inertial measurement unit (MIMU) networks is proposed to obtain both BCoM acceleration and velocity. The proposed framework was validated as a proof of concept in one transfemoral amputee against data from force plates (acceleration) and an optoelectronic system (acceleration and velocity). The impact in terms of estimation accuracy when using a sensor network rather than a single MIMU at trunk level was also investigated. The estimated velocity and acceleration reached a strong agreement (\u03c1 &gt; 0.89) and good accuracy compared to reference data (normalized root mean square error (NRMSE) &lt; 13.7%) in the anteroposterior and vertical directions when using three MIMUs on the trunk and both shanks and in all three directions when adding MIMUs on both thighs (\u03c1 &gt; 0.89, NRMSE \u2264 14.0% in the mediolateral direction). Conversely, only the vertical component of the BCoM kinematics was accurately captured when considering a single MIMU. These results suggest that inertial sensor networks may represent a valid alternative to laboratory-based instruments for 3D BCoM kinematics quantification in lower-limb amputees.<\/jats:p>","DOI":"10.3390\/s21093129","type":"journal-article","created":{"date-parts":[[2021,4,30]],"date-time":"2021-04-30T10:53:29Z","timestamp":1619780009000},"page":"3129","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["Estimation of 3D Body Center of Mass Acceleration and Instantaneous Velocity from a Wearable Inertial Sensor Network in Transfemoral Amputee Gait: A Case Study"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7093-5096","authenticated-orcid":false,"given":"Emeline","family":"Simonetti","sequence":"first","affiliation":[{"name":"INI\/CERAH, 47 Rue de l\u2019Echat, 94000 Cr\u00e9teil, France"},{"name":"Institut de Biom\u00e9canique Humaine Georges Charpak, Arts et M\u00e9tiers, 151 Boulevard de l\u2019H\u00f4pital, 75013 Paris, France"},{"name":"Department of Movement, Human and Health Sciences, Interuniversity Centre of Bioengineering of the Human Neuromusculoskeletal System, University of Rome \u201cForo Italico\u201d, Piazza Lauro de Bosis 15, 00135 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9055-3981","authenticated-orcid":false,"given":"Elena","family":"Bergamini","sequence":"additional","affiliation":[{"name":"Department of Movement, Human and Health Sciences, Interuniversity Centre of Bioengineering of the Human Neuromusculoskeletal System, University of Rome \u201cForo Italico\u201d, Piazza Lauro de Bosis 15, 00135 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2359-6076","authenticated-orcid":false,"given":"Giuseppe","family":"Vannozzi","sequence":"additional","affiliation":[{"name":"Department of Movement, Human and Health Sciences, Interuniversity Centre of Bioengineering of the Human Neuromusculoskeletal System, University of Rome \u201cForo Italico\u201d, Piazza Lauro de Bosis 15, 00135 Roma, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joseph","family":"Bascou","sequence":"additional","affiliation":[{"name":"INI\/CERAH, 47 Rue de l\u2019Echat, 94000 Cr\u00e9teil, France"},{"name":"Institut de Biom\u00e9canique Humaine Georges Charpak, Arts et M\u00e9tiers, 151 Boulevard de l\u2019H\u00f4pital, 75013 Paris, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"H\u00e9l\u00e8ne","family":"Pillet","sequence":"additional","affiliation":[{"name":"Institut de Biom\u00e9canique Humaine Georges Charpak, Arts et M\u00e9tiers, 151 Boulevard de l\u2019H\u00f4pital, 75013 Paris, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1471","DOI":"10.1016\/j.jbiomech.2011.03.014","article-title":"The mathematical description of the body centre of mass 3D path in human and animal locomotion","volume":"44","author":"Minetti","year":"2011","journal-title":"J. Biomech."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3389\/fphys.2017.00129","article-title":"On the estimation accuracy of the 3D body center of mass trajectory during human locomotion: Inverse vs. forward dynamics","volume":"8","author":"Pavei","year":"2017","journal-title":"Front. Physiol."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1","DOI":"10.3389\/fneur.2019.00999","article-title":"The Motion of Body Center of Mass During Walking: A Review Oriented to Clinical Applications","volume":"10","author":"Tesio","year":"2019","journal-title":"Front. Neurol."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.jbiomech.2004.03.025","article-title":"The condition for dynamic stability","volume":"38","author":"Hof","year":"2005","journal-title":"J. Biomech."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1480","DOI":"10.2522\/ptj.20130431","article-title":"Stepping Asymmetry Among Individuals With Unilateral Transtibial Limb Loss Might Be Functional in Terms of Gait Stability","volume":"94","author":"Hak","year":"2014","journal-title":"Phys. Ther."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Al Abiad, N., Pillet, H., and Watier, B. (2020). A mechanical descriptor of instability in human locomotion: Experimental findings in control subjects and people with transfemoral amputation. Appl. Sci., 10.","DOI":"10.3390\/app10030840"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"3717","DOI":"10.1242\/jeb.205.23.3717","article-title":"Mechanical work for step-to-step transitions is a major determinant of the metabolic cost of human walking","volume":"205","author":"Donelan","year":"2002","journal-title":"J. Exp. Biol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1177\/0954411913514036","article-title":"Mechanical work performed by individual limbs of transfemoral amputees during step-to-step transitions: Effect of walking velocity","volume":"228","author":"Bonnet","year":"2014","journal-title":"Proc. Inst. Mech. Eng. Part H J. Eng. Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1186\/s12984-019-0508-x","article-title":"Energy cost of ambulation in trans-tibial amputees using a dynamic-response foot with hydraulic versus rigid \u201cankle\u201d: Insights from body centre of mass dynamics","volume":"16","author":"Askew","year":"2019","journal-title":"J. Neuroeng. Rehabil."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1080\/03093640902777254","article-title":"Symmetry in external work (SEW): A novel method of quantifying gait differences between prosthetic feet","volume":"33","author":"Agrawal","year":"2009","journal-title":"Prosthet. Orthot. Int."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1223","DOI":"10.1016\/0021-9290(95)00178-6","article-title":"Adjustments to Zatsiorsky-Seluyanov\u2019s segment inertia parameters","volume":"29","year":"1996","journal-title":"J. Biomech."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1016\/j.gaitpost.2016.04.032","article-title":"A simplified marker set to define the center of mass for stability analysis in dynamic situations","volume":"48","author":"Tisserand","year":"2016","journal-title":"Gait Posture"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1016\/j.gaitpost.2018.03.048","article-title":"Comparison of segmental analysis and sacral marker methods for determining the center of mass during level and slope walking","volume":"62","author":"Jeong","year":"2018","journal-title":"Gait Posture"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"97","DOI":"10.1016\/j.clinbiomech.2017.07.015","article-title":"Validation of simplified centre of mass models during gait in individuals with chronic stroke","volume":"48","author":"Huntley","year":"2017","journal-title":"Clin. Biomech."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"637","DOI":"10.1016\/S0167-9457(99)00022-6","article-title":"Comparing methods of estimating the total body centre of mass in three-dimensions in normal and pathological gaits","volume":"18","author":"Eames","year":"1999","journal-title":"Hum. Mov. Sci."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/j.jbiomech.2017.05.007","article-title":"Does the anthropometric model influence whole-body center of mass calculations in gait?","volume":"59","author":"Catena","year":"2017","journal-title":"J. Biomech."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Ancillao, A., Tedesco, S., Barton, J., and O\u2019flynn, B. (2018). Indirect measurement of ground reaction forces and moments by means of wearable inertial sensors: A systematic review. Sensors, 18.","DOI":"10.3390\/s18082564"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Shahabpoor, E., and Pavic, A. (2017). Measurement of Walking Ground Reactions in Real-Life Environments: A Systematic Review of Techniques and Technologies. Sensors, 17.","DOI":"10.3390\/s17092085"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"18625","DOI":"10.3390\/s141018625","article-title":"Estimating Orientation Using Magnetic and Inertial Sensors and Different Sensor Fusion Approaches: Accuracy Assessment in Manual and Locomotion Tasks","volume":"14","author":"Bergamini","year":"2014","journal-title":"Sensors"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1489","DOI":"10.3390\/s110201489","article-title":"Estimating three-dimensional orientation of human body parts by inertial\/magnetic sensing","volume":"11","author":"Sabatini","year":"2011","journal-title":"Sensors"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Karatsidis, A., Bellusci, G., Schepers, H.M., de Zee, M., Andersen, M.S., and Veltink, P.H. (2017). Estimation of ground reaction forces and moments during gait using only inertial motion capture. Sensors, 17.","DOI":"10.3390\/s17010075"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"940","DOI":"10.1080\/17461391.2018.1465126","article-title":"An accurate estimation of the horizontal acceleration of a rower\u2019s centre of mass using inertial sensors: A validation","volume":"18","author":"Lintmeijer","year":"2018","journal-title":"Eur. J. Sport Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"850","DOI":"10.3389\/fphys.2017.00850","article-title":"An Inertial Sensor-Based Method for Estimating the Athlete\u2019s Relative Joint Center Positions and Center of Mass Kinematics in Alpine Ski Racing","volume":"8","author":"Fasel","year":"2017","journal-title":"Front. Physiol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1243","DOI":"10.1109\/TNSRE.2018.2830976","article-title":"Real-life measurement of tri-axial walking ground reaction forces using optimal network of wearable inertial measurement units","volume":"26","author":"Shahabpoor","year":"2018","journal-title":"IEEE Trans. Neural Syst. Rehabil. Eng."},{"key":"ref_25","unstructured":"(2021, April 09). Xsens MVN BIOMECH Product Webpage. Available online: https:\/\/www.xsens.com\/products\/mvn-analyze."},{"key":"ref_26","unstructured":"(2021, April 09). Noraxon myoMOTION Features Webpage. Available online: https:\/\/www.noraxon.com\/our-products\/myomotion\/#1541097720904-fe85b033-bcdd."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1371\/journal.pone.0213064","article-title":"Validity of inertial sensor based 3D joint kinematics of static and dynamic sport and physiotherapy specific movements","volume":"14","author":"Teufl","year":"2019","journal-title":"PLoS ONE"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1385","DOI":"10.1109\/TBME.2006.873678","article-title":"Estimation and visualization of sagittal kinematics of lower limbs orientation using body-fixed sensors","volume":"53","author":"Dejnabadi","year":"2006","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"373","DOI":"10.1016\/j.gaitpost.2010.12.006","article-title":"A spot check for assessing static orientation consistency of inertial and magnetic sensing units","volume":"33","author":"Picerno","year":"2011","journal-title":"Gait Posture"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"199","DOI":"10.1016\/j.gaitpost.2017.10.016","article-title":"Camera pose estimation to improve accuracy and reliability of joint angles assessed with attitude and heading reference systems","volume":"59","author":"Lebel","year":"2018","journal-title":"Gait Posture"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Guaitolini, M., Aprigliano, F., Mannini, A., Micera, S., Monaco, V., and Sabatini, A.M. (2019). Ambulatory Assessment of the Dynamic Margin of Stability Using an Inertial Sensor Network. Sensors, 19.","DOI":"10.3390\/s19194117"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.measurement.2014.03.004","article-title":"Experimental evaluation of accuracy and repeatability of a novel body-to-sensor calibration procedure for inertial sensor-based gait analysis","volume":"52","author":"Palermo","year":"2014","journal-title":"Measurement"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"8844","DOI":"10.1109\/JSEN.2020.2983695","article-title":"A Wearable Magnetometer-Free Motion Capture System: Innovative Solutions for Real-World Applications","volume":"20","author":"Ligorio","year":"2020","journal-title":"IEEE Sens. J."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"2080","DOI":"10.1109\/TBME.2012.2197211","article-title":"Use of inertial sensors for ambulatory assessment of center-of-mass displacements during walking","volume":"59","author":"Schepers","year":"2012","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1308","DOI":"10.1109\/TNSRE.2020.2984809","article-title":"Portable Gait Lab: Estimating 3D GRF Using a Pelvis IMU in a Foot IMU Defined Frame","volume":"28","author":"Refai","year":"2020","journal-title":"IEEE Trans. Neural Syst. Rehabil. Eng."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1578","DOI":"10.1016\/j.jbiomech.2009.03.049","article-title":"IMU: Inertial sensing of vertical CoM movement","volume":"42","author":"Esser","year":"2009","journal-title":"J. Biomech."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1016\/j.gaitpost.2005.12.016","article-title":"Criterion validity of 3D trunk accelerations to assess external work and power in able-bodied gait","volume":"25","author":"Meichtry","year":"2007","journal-title":"Gait Posture"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Sabatini, A.M., and Mannini, A. (2016). Ambulatory Assessment of Instantaneous Velocity during Walking Using Inertial Sensor Measurements. Sensors, 16.","DOI":"10.3390\/s16122206"},{"key":"ref_39","first-page":"354","article-title":"Estimation of Center of Mass Trajectory using Wearable Sensors during Golf Swing","volume":"14","author":"Najafi","year":"2015","journal-title":"J. Sports Sci. Med."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"460","DOI":"10.1016\/j.clinbiomech.2011.11.011","article-title":"Gait asymmetry of transfemoral amputees using mechanical and microprocessor-controlled prosthetic knees","volume":"27","author":"Kaufman","year":"2012","journal-title":"Clin. Biomech."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"87","DOI":"10.1016\/j.apmr.2007.08.136","article-title":"Three-Dimensional Motions of Trunk and Pelvis During Transfemoral Amputee Gait","volume":"89","author":"Sapin","year":"2008","journal-title":"Arch. Phys. Med. Rehabil."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1016\/j.jbiomech.2018.08.015","article-title":"Estimation of vertical walking ground reaction force in real-life environments using single IMU sensor","volume":"79","author":"Shahabpoor","year":"2018","journal-title":"J. Biomech."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"272","DOI":"10.1016\/j.gaitpost.2009.11.003","article-title":"A body-fixed-sensor-based analysis of power during sit-to-stand movements","volume":"31","author":"Zijlstra","year":"2010","journal-title":"Gait Posture"},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Simonetti, E., Bergamini, E., Bascou, J., Vannozzi, G., and Pillet, H. (2021). Optimal sensor networks for the estimation of 3D body center of mass acceleration in people with transfemoral amputation. Gait Posture, under review.","DOI":"10.1016\/j.gaitpost.2021.08.017"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"6102","DOI":"10.3390\/s120506102","article-title":"Inertial Sensor-Based Methods in Walking Speed Estimation: A Systematic Review","volume":"12","author":"Yang","year":"2012","journal-title":"Sensors"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1016\/j.gaitpost.2009.09.014","article-title":"Evaluation of force plate-less estimation of the trajectory of the centre of pressure during gait. Comparison of two anthropometric models","volume":"31","author":"Pillet","year":"2010","journal-title":"Gait Posture"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"239","DOI":"10.1016\/j.gaitpost.2016.11.008","article-title":"25 years of lower limb joint kinematics by using inertial and magnetic sensors: A review of methodological approaches","volume":"51","author":"Picerno","year":"2017","journal-title":"Gait Posture"},{"key":"ref_48","doi-asserted-by":"crossref","unstructured":"Miezal, M., Taetz, B., and Bleser, G. (2016). On Inertial Body Tracking in the Presence of Model Calibration Errors. Sensors, 16.","DOI":"10.3390\/s16071132"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"152","DOI":"10.1186\/1743-0003-11-152","article-title":"Estimation of step-by-step spatio-temporal parameters of normal and impaired gait using shank-mounted magneto-inertial sensors: Application to elderly, hemiparetic, parkinsonian and choreic gait","volume":"11","author":"Trojaniello","year":"2014","journal-title":"J. Neuroeng. Rehabil."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"461","DOI":"10.1007\/s11517-019-02098-4","article-title":"Gait event detection using inertial measurement units in people with transfemoral amputation: A comparative study","volume":"58","author":"Simonetti","year":"2020","journal-title":"Med. Biol. Eng. Comput."},{"key":"ref_51","doi-asserted-by":"crossref","unstructured":"Duraffourg, C., Bonnet, X., Dauriac, B., and Pillet, H. (2019). Real time estimation of the pose of a lower limb prosthesis from a single shank mounted IMU. Sensors, 19.","DOI":"10.3390\/s19132865"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"3780","DOI":"10.1016\/j.jbiomech.2014.06.014","article-title":"A smart device inertial-sensing method for gait analysis","volume":"47","author":"Steins","year":"2014","journal-title":"J. Biomech."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"2750","DOI":"10.1016\/j.jbiomech.2008.06.001","article-title":"Whole body inverse dynamics over a complete gait cycle based only on measured kinematics","volume":"41","author":"Ren","year":"2008","journal-title":"J. Biomech."},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Tunca, C., Pehlivan, N., Ak, N., Arnrich, B., Salur, G., and Ersoy, C. (2017). Inertial sensor-based robust gait analysis in non-hospital settings for neurological disorders. Sensors, 17.","DOI":"10.3390\/s17040825"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"230949901983266","DOI":"10.1177\/2309499019832665","article-title":"Comparison of gait variability and symmetry in trained individuals with transtibial and transfemoral limb loss","volume":"27","author":"Keklicek","year":"2019","journal-title":"J. Orthop. Surg."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"110","DOI":"10.1016\/j.gaitpost.2016.01.014","article-title":"Estimation of foot trajectory during human walking by a wearable inertial measurement unit mounted to the foot","volume":"45","author":"Kitagawa","year":"2016","journal-title":"Gait Posture"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"2999","DOI":"10.1016\/j.jbiomech.2010.07.003","article-title":"3D gait assessment in young and elderly subjects using foot-worn inertial sensors","volume":"43","author":"Mariani","year":"2010","journal-title":"J. Biomech."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1080\/10255842.2010.534465","article-title":"IMU-based ambulatory walking speed estimation in constrained treadmill and overground walking","volume":"15","author":"Yang","year":"2012","journal-title":"Comput. Methods Biomech. Biomed. Eng."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1080\/10255842.2017.1382920","article-title":"Estimation of body segment inertia parameters from 3D body scanner images: A semi-automatic method dedicated to human movement analysis applications","volume":"20","author":"Robert","year":"2017","journal-title":"Comput. Methods Biomech. Biomed. Eng."},{"key":"ref_60","first-page":"205566831881345","article-title":"Inertial measurement unit-based pose estimation: Analyzing and reducing sensitivity to sensor placement and body measures","volume":"6","author":"Kianifar","year":"2019","journal-title":"J. Rehabil. Assist. Technol. Eng."},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"492","DOI":"10.1177\/0309364619865814","article-title":"Are wearable insoles a validated tool for quantifying transfemoral amputee gait asymmetry?","volume":"43","author":"Loiret","year":"2019","journal-title":"Prosthet. Orthot. Int."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1016\/S0021-9290(01)00169-5","article-title":"Simultaneous positive and negative external mechanical work in human walking","volume":"35","author":"Donelan","year":"2002","journal-title":"J. Biomech."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"639","DOI":"10.1113\/jphysiol.1976.sp011613","article-title":"The sources of external work in level walking and running","volume":"262","author":"Cavagna","year":"1976","journal-title":"J. Physiol."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1371\/journal.pone.0185731","article-title":"Impact of anatomical placement of an accelerometer on prediction of physical activity energy expenditure in lower-limb amputees","volume":"12","author":"Ladlow","year":"2017","journal-title":"PLoS ONE"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/9\/3129\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:56:00Z","timestamp":1760162160000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/21\/9\/3129"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,4,30]]},"references-count":64,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2021,5]]}},"alternative-id":["s21093129"],"URL":"https:\/\/doi.org\/10.3390\/s21093129","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,4,30]]}}}