{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,21]],"date-time":"2026-04-21T15:32:23Z","timestamp":1776785543990,"version":"3.51.2"},"reference-count":195,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2022,6,12]],"date-time":"2022-06-12T00:00:00Z","timestamp":1654992000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Polish National Science Centre","award":["DEC-2013\/08\/W\/HS6\/00333, Symfonia 1"],"award-info":[{"award-number":["DEC-2013\/08\/W\/HS6\/00333, Symfonia 1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Currently, there is an intensive development of bipedal walking robots. The most known solutions are based on the use of the principles of human gait created in nature during evolution. Modernbipedal robots are also based on the locomotion manners of birds. This review presents the current state of the art of bipedal walking robots based on natural bipedal movements (human and bird) as well as on innovative synthetic solutions. Firstly, an overview of the scientific analysis of human gait is provided as a basis for the design of bipedal robots. The full human gait cycle that consists of two main phases is analysed and the attention is paid to the problem of balance and stability, especially in the single support phase when the bipedal movement is unstable. The influences of passive or active gait on energy demand are also discussed. Most studies are explored based on the zero moment. Furthermore, a review of the knowledge on the specific locomotor characteristics of birds, whose kinematics are derived from dinosaurs and provide them with both walking and running abilities, is presented. Secondly, many types of bipedal robot solutions are reviewed, which include nature-inspired robots (human-like and birdlike robots) and innovative robots using new heuristic, synthetic ideas for locomotion. Totally 45 robotic solutions are gathered by thebibliographic search method. Atlas was mentioned as one of the most perfect human-like robots, while the birdlike robot cases were Cassie and Digit. Innovative robots are presented, such asslider robot without knees, robots with rotating feet (3 and 4 degrees of freedom), and the hybrid robot Leo, which can walk on surfaces and fly. In particular, the paper describes in detail the robots\u2019 propulsion systems (electric, hydraulic), the structure of the lower limb (serial, parallel, mixed mechanisms), the types and structures of control and sensor systems, and the energy efficiency of the robots. Terrain roughness recognition systems using different sensor systems based on light detection and ranging or multiple cameras are introduced. A comparison of performance, control and sensor systems, drive systems, and achievements of known human-like and birdlike robots is provided. Thirdly, for the first time, the review comments on the future of bipedal robots in relation to the concepts of conventional (natural bipedal) and synthetic unconventional gait. We critically assess and compare prospective directions for further research that involve the development of navigation systems, artificial intelligence, collaboration with humans, areas for the development of bipedal robot applications in everyday life, therapy, and industry.<\/jats:p>","DOI":"10.3390\/s22124440","type":"journal-article","created":{"date-parts":[[2022,6,13]],"date-time":"2022-06-13T02:01:44Z","timestamp":1655085704000},"page":"4440","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":93,"title":["Recent Advances in Bipedal Walking Robots: Review of Gait, Drive, Sensors and Control Systems"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5253-590X","authenticated-orcid":false,"given":"Tadeusz","family":"Mikolajczyk","sequence":"first","affiliation":[{"name":"Department of Production Engineering, Bydgoszcz University of Science and Technology, Al. Prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2769-3068","authenticated-orcid":false,"given":"Emilia","family":"Miko\u0142ajewska","sequence":"additional","affiliation":[{"name":"Department of Physiotherapy, LudwikRydygier Collegium Medicum in Bydgoszcz, Nicolaus Copernicus University, 87-100 Torun, Poland"},{"name":"Neurocognitive Laboratory, Centre for Modern Interdisciplinary Technologies, Nicolaus Copernicus University, 87-100 Torun, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4041-385X","authenticated-orcid":false,"given":"Hayder F. N.","family":"Al-Shuka","sequence":"additional","affiliation":[{"name":"Department of Aeronautical Engineering, Baghdad University, Baghdad 10001, Iraq"},{"name":"School of Control Science and Engineering, Shandong University, Jinan 250100, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tomasz","family":"Malinowski","sequence":"additional","affiliation":[{"name":"Department of Production Engineering, Bydgoszcz University of Science and Technology, Al. Prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4965-5521","authenticated-orcid":false,"given":"Adam","family":"K\u0142odowski","sequence":"additional","affiliation":[{"name":"Laboratory of machine Design, Lappeenranta University of Technology, 53850 Lappeenranta, Finland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5568-8928","authenticated-orcid":false,"given":"Danil Yurievich","family":"Pimenov","sequence":"additional","affiliation":[{"name":"Department of Automated Mechanical Engineering, South Ural State University, Lenin Prosp. 76, 454080 Chelyabinsk, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2861-8817","authenticated-orcid":false,"given":"Tomasz","family":"Paczkowski","sequence":"additional","affiliation":[{"name":"Department of Production Engineering, Bydgoszcz University of Science and Technology, Al. Prof. S. Kaliskiego 7, 85-796 Bydgoszcz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3508-8930","authenticated-orcid":false,"given":"Fuwen","family":"Hu","sequence":"additional","affiliation":[{"name":"School of Mechanical and Material Engineering, North China University of Technology, Beijing 100144, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3992-8602","authenticated-orcid":false,"given":"Khaled","family":"Giasin","sequence":"additional","affiliation":[{"name":"School of Mechanical and Design Engineering, University of Portsmouth, Portsmouth PO1 3DJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4157-2796","authenticated-orcid":false,"given":"Dariusz","family":"Miko\u0142ajewski","sequence":"additional","affiliation":[{"name":"Institute of Computer Science, Kazimierz Wielki University, 85-064 Bydgoszcz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8743-6602","authenticated-orcid":false,"given":"Marek","family":"Macko","sequence":"additional","affiliation":[{"name":"Faculty of Mechatronics, Kazimierz Wielki University, 85-064 Bydgoszcz, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Morecki, A., and Knapczyk, J. (1999). CISM courses lecture notes. Basis of Robotics: Theory and Components of Manipulators and Robots, Springer.","DOI":"10.1007\/978-3-7091-2532-8_16"},{"key":"ref_2","unstructured":"Wolovich, W.A. (1987). Robotics: Basic Analysis and Design, Saunders College Publishing."},{"key":"ref_3","unstructured":"Lima, P., and Ribeiro, M.I. (2002). Mobile Robotics, Instituto Superior T\u00e9cnico\/Instituto de Sistemas e Rob\u00f3tica. Course Handouts."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1753","DOI":"10.1177\/1077546311403180","article-title":"A literature review on the optimization of legged robots","volume":"18","author":"Silva","year":"2012","journal-title":"J. Vib. Control"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"513","DOI":"10.1016\/S0021-9290(02)00419-0","article-title":"Theories of bipedal walking: An odyssey","volume":"36","author":"Vaughan","year":"2003","journal-title":"J. Biomech."},{"key":"ref_6","unstructured":"Bekey, G.A. (2005). Autonomous Robots: From Biological Inspiration to Implementation and Control, MIT Press."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1109\/MEX.1986.4307016","article-title":"Legged robots that balance","volume":"1","author":"Raibert","year":"1986","journal-title":"IEEE Expert"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"2440","DOI":"10.1017\/S0263574715000107","article-title":"Multi-level control of zero-moment point-based humanoid biped robots: A review","volume":"34","author":"Corves","year":"2016","journal-title":"Robotica"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"907","DOI":"10.1017\/S0263574713001124","article-title":"Modeling, stability and walking pattern generators of biped robots: A review","volume":"32","author":"Allmendinger","year":"2014","journal-title":"Robotica"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1850019","DOI":"10.1142\/S0219843618500196","article-title":"Design performance characteristics of a social robot companion arash for pediatric hospitals","volume":"15","author":"Meghdari","year":"2018","journal-title":"Int. J. Hum. Robot."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1724","DOI":"10.1016\/j.jamda.2020.05.036","article-title":"Effects of a humanoid companion robot on dementia symptoms and caregiver distress for residents in long-term care","volume":"21","author":"Chen","year":"2020","journal-title":"J. Am. Med. Dir. Assoc."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"759","DOI":"10.1007\/s10846-019-01075-1","article-title":"Humanoid robot as a teacher\u2019s assistant: Helping children with autism to learn social and academic skills","volume":"98","author":"Qidwai","year":"2020","journal-title":"J. Intell. Robot. Syst."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"3441","DOI":"10.1098\/rstb.2009.0198","article-title":"Computation of emotions in man and machines","volume":"364","author":"Robinson","year":"2009","journal-title":"Phil. Trans. R. Soc. B"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"157","DOI":"10.1142\/S0219843604000083","article-title":"Zero-moment point\u2014Thirty five years of its life","volume":"1","author":"Borovac","year":"2004","journal-title":"Int. J. Hum. Robot."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"411","DOI":"10.1049\/ip-cta:20045007","article-title":"Zero-moment point trajectory modelling of a biped walking robot using an adaptive neuro-fuzzy system","volume":"152","author":"Kim","year":"2005","journal-title":"IEEE Proc. Control Theory Appl."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Park, I.-W., Kimand, J.-Y., and Oh, J.-H. (2006, January 4\u20136). Online biped walking pattern generation for humanoid robot KHR-3 (kaist humanoid robot-3: Hubo). Proceedings of the 2006 6th IEEE-RAS International Conference on Humanoid Robots, Genova, Italy.","DOI":"10.1109\/ICHR.2006.321303"},{"key":"ref_17","unstructured":"Zhu, W.-H. (2010). Virtual Decomposition Control: Toward Hyper Degrees of Freedom Robots, Springer Science & Business Media."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"963","DOI":"10.1109\/TAC.1977.1101650","article-title":"An approach to analyzing biped locomotion dynamics and designing robot locomotion controls","volume":"22","author":"Golliday","year":"1977","journal-title":"IEEE Trans. Autom. Control"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1027","DOI":"10.1163\/156855308X324749","article-title":"Overview of the Lucy project: Dynamic stabilization of a biped powered by pneumatic artificial muscles","volume":"22","author":"Vanderborght","year":"2008","journal-title":"Adv. Robot."},{"key":"ref_20","unstructured":"Zieli\u0144ska, T. (2013). Walking Machines: Basics, Design, Control and Biological Patterns, WydawnictwoNaukowe PWN."},{"key":"ref_21","unstructured":"Raibert, M., Tzafestas, S., and Tzafestas, C. (1993, January 17\u201320). Comparative simulation study of three control techniques applied to a biped robot. Proceedings of the IEEE Systems Man and Cybernetics Conference\u2014SMC, Le Toruquet, France."},{"key":"ref_22","unstructured":"Vukobratovic, M., Ciricand, V., and Hristic, D. (1972, January 12\u201317). Contribution to the study of active exoskeletons. Proceedings of the 5th International Federation of Automatic Control Congress, Paris, France."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"459","DOI":"10.1142\/S0219843607001163","article-title":"When were active exoskeletons actually born?","volume":"4","author":"Vukobratovic","year":"2007","journal-title":"Int. J. Hum. Robot."},{"key":"ref_24","first-page":"11","article-title":"Honda humanoid robots development","volume":"365","author":"Hirose","year":"2007","journal-title":"Philos. Trans. R. Soc. Math. Phys. Eng. Sci."},{"key":"ref_25","unstructured":"Wahde, M., and Pettersson, J. (2002, January 24\u201326). A brief review of bipedal robotics research. Proceedings of the 8th UK Mechatronics Forum International Conference (Mechatronics 2002), Enschede, The Netherlands."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Ceccarelli, M. (2004). Biped robots: The state of art. International Symposium on History of Machines and Mechanisms, Springer.","DOI":"10.1007\/1-4020-2204-2"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Shi, X., Gao, J., Lu, Y., Tian, D., and Liu, Y. (2021). Biped Walking Based on Stiffness Optimization and Hierarchical Quadratic Programming. Sensors, 21.","DOI":"10.3390\/s21051696"},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Ficht, G., Farazi, H., Brandenburger, A., Rodriguez, D., Pavlichenko, D., Allgeuer, P., Hosseini, M., and Behnke, S. (2018, January 6\u20139). NimbRo-OP2X: Adult-sized open-source 3D printed humanoid robot. Proceedings of the 2018 IEEE-RAS 18th International Conference on Humanoid Robots (Humanoids), Beijing, China.","DOI":"10.1109\/HUMANOIDS.2018.8625038"},{"key":"ref_29","unstructured":"Ye, X., Bin, L., Anhuan, X., and Dan, Z. (2019, January 17\u201319). A review: Robust locomotion for biped humanoid robots. Proceedings of the Journal of Physics: Conference Series, 2020 4th International Conference on Control Engineering and Artificial Intelligence (CCEAI 2020), Singapore."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"201","DOI":"10.1007\/s43154-021-00050-9","article-title":"Bipedal humanoid hardware design: A technology review","volume":"2","author":"Ficht","year":"2021","journal-title":"Curr Robot. Rep."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1080\/01691864.2017.1308270","article-title":"A brief review of dynamics and control of underactuated biped robots","volume":"31","author":"Gubta","year":"2017","journal-title":"Adv. Robot."},{"key":"ref_32","unstructured":"Westervelt, E.R., Grizzle, J.W., Chevallereau, C., Choi, J.H., and Morris, B. (2007). Feedback Control of Dynamic Bipedal Robot Locomotion, CRC Press."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Sadati, N., Dumont, G.A., Hamed, K.A., and Gruver, W.A. (2012). Hybrid Control and Motion Planning of Dynamical Legged Locomotion, IEEE Press.","DOI":"10.1002\/9781118393741"},{"key":"ref_34","first-page":"026101","article-title":"Introduction to focus issue: Bipedal locomotion\u2014from robots to humans","volume":"19","author":"Milton","year":"2009","journal-title":"AIP J. Nonlinear Sci."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Macleod, C.A., Meng, L., Conwayand, B.A., and Porr, B. (2014). Reflex control of robotic gait using human walking data. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0109959"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"016011","DOI":"10.1088\/1748-3190\/10\/1\/016011","article-title":"On extracting design principles from biology: II. Case study\u2014The effect of knee direction on bipedal robot running efficiency","volume":"10","author":"Haberland","year":"2015","journal-title":"Bioinspir. Biomim."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"036005","DOI":"10.1088\/1748-3182\/7\/3\/036005","article-title":"Robots in human biomechanics a study on ankle push-off in walking","volume":"7","author":"Renjewski","year":"2012","journal-title":"Bioinspir. Biomim."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"523","DOI":"10.1177\/02783649922066376","article-title":"Postural stability of biped robots and the foot-rotation indicator (FRI) point","volume":"18","author":"Goswami","year":"1999","journal-title":"Int. J. Robot. Res."},{"key":"ref_39","unstructured":"McGeer, T. (1990, January 13\u201318). Passive walking with knees. Proceedings of the IEEE International Conference on Robotics and Automation, Cincinnati, OH, USA."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"0542","DOI":"10.1098\/rsif.2015.0542","article-title":"Adaptation mechanism of interlimb coordination in human split-belt treadmill walking through learning of foot contact timing: A robotics study","volume":"12","author":"Fujiki","year":"2015","journal-title":"J. R. Soc. Interface"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1861","DOI":"10.1093\/brain\/awm035","article-title":"Locomotor adaptation on a split-belt treadmill can improve walking symmetry post-stroke","volume":"130","author":"Reisman","year":"2007","journal-title":"Brain"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"429","DOI":"10.1016\/j.gaitpost.2005.05.006","article-title":"Adaptations in interlimb and intralimb coordination to asymmetrical loading in human walking","volume":"23","author":"Haddad","year":"2006","journal-title":"Gait Posture"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"2403","DOI":"10.1152\/jn.00089.2005","article-title":"Interlimb coordination during locomotion: What can be adapted and stored?","volume":"94","author":"Reisman","year":"2005","journal-title":"J. Neurophysiol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1016\/B978-0-444-53752-2.00013-8","article-title":"Locomotor adaptation","volume":"Volume 191","author":"Vasudevan","year":"2011","journal-title":"Progress in Brain Research"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"187","DOI":"10.2522\/ptj.20090073","article-title":"Neurophysiologic and rehabilitation insights from the split-belt and other locomotor adaptation paradigms","volume":"90","author":"Reisman","year":"2010","journal-title":"Phys. Ther."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1017\/S0263574704000591","article-title":"Compensatory motion control for a biped walking robot","volume":"23","author":"Lim","year":"2005","journal-title":"Robotica"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"536","DOI":"10.3389\/fnhum.2018.00536","article-title":"Neural substrates of cognitive motor interference during walking; peripheral and central mechanisms","volume":"12","author":"Mahmoud","year":"2019","journal-title":"Front. Hum. Neurosci."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"313","DOI":"10.1016\/0021-9290(73)90053-5","article-title":"A mathematical model for evaluation of forces in lower extremeties of the musculo-skeletal system","volume":"6","author":"Seireg","year":"1973","journal-title":"J. Biomech."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"433","DOI":"10.1109\/TBME.1973.324217","article-title":"Effect of model complexity and gait criteria on the synthesis of bipedal locomotion","volume":"6","author":"Townsend","year":"1973","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_50","unstructured":"Migliore, A. (2008). The Role of Passive Joint Stiffness and Active Knee Control in Robotic Leg Swinging: Applications to Dynamic Walking. [Ph.D. Thesis, Georgia University]."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"647","DOI":"10.1109\/TMECH.2009.2033593","article-title":"Differentially flat design of bipeds ensuring limit cycles","volume":"14","author":"Sangwan","year":"2009","journal-title":"IEEE Trans. Mechatron."},{"key":"ref_52","unstructured":"Chevallereau, C., Bessonnet, G., Abba, G., and Aoustin, Y. (2013). Bipedal Robots: Modeling, Design and Walking Synthesis, John & Wiley & Sons."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1115\/1.3149608","article-title":"A Control theoretic study on dynamical biped locomotion","volume":"102","author":"Miyazaki","year":"1980","journal-title":"ASME J. Dyn. Sys. Meas."},{"key":"ref_54","first-page":"0610544","article-title":"Zero-moment point method for stable biped walking","volume":"62","author":"Dekker","year":"2009","journal-title":"Eindh. Univ. Technol."},{"key":"ref_55","unstructured":"Whittle, M.W. (2014). Gait Analysis: An Introduction, Butterworth-Heinemann."},{"key":"ref_56","doi-asserted-by":"crossref","unstructured":"van Zutven, P., Kosti\u0107, D., and Nijmeijer, H. (2010). On the stability of bipedal walking. Lecutre Notes in Computer Sciences, Springer.","DOI":"10.1007\/978-3-642-17319-6_47"},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1016\/j.jphysparis.2009.07.007","article-title":"Biological inspiration used for robots motion synthesis","volume":"103","year":"2009","journal-title":"J. Physiol. Paris"},{"key":"ref_58","unstructured":"Nicholls, E. (1998). Bipedal Dynamic Walking in Robotics. [Ph.D. Thesis, The University of Western Australia]. Available online: https:\/\/citeseerx.ist.psu.edu\/viewdoc\/download?doi=10.1.1.590.6362&rep=rep1&type=pdf."},{"key":"ref_59","doi-asserted-by":"crossref","unstructured":"Pratt, J.E., and Tedrake, R. (2006). Velocity-based stability margins for fast bipedal walking. Fast Motions in Biomechanics and Robotics, Springer.","DOI":"10.1007\/978-3-540-36119-0_14"},{"key":"ref_60","doi-asserted-by":"crossref","unstructured":"Pratt, J., Carff, J., Drakunov, S., and Goswami, A. (2006, January 4\u20136). Capture point: A step toward humanoid push recovery. Proceedings of the 6th IEEE-RAS International Conference on Humanoid Robots, Genova, Italy.","DOI":"10.1109\/ICHR.2006.321385"},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"011009","DOI":"10.1115\/1.2815334","article-title":"Introduction of the foot placement estimator: A dynamic measure of balance for bipedal robotics","volume":"3","author":"Wight","year":"2008","journal-title":"J. Comput. Nonlinear Dyn."},{"key":"ref_62","doi-asserted-by":"crossref","unstructured":"Znegui, W., Gritli, H., and Belghith, S. (2021, January 20\u201322). Analysis and control of the dynamic walking of the compass biped walker using poincar\u00e9 maps: Comparison between two design approaches. Proceedings of the 2021 IEEE 2nd International Conference on Signal, Control and Communication (SCC), Tunis, Tunisia.","DOI":"10.1109\/SCC53769.2021.9768342"},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"2882","DOI":"10.1109\/TAC.2009.2033760","article-title":"Transverse linearization for impulsive mechanical systems with one passive link","volume":"54","author":"Shiriaev","year":"2009","journal-title":"IEEE Trans. Autom. Control."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"889","DOI":"10.1016\/j.robot.2014.01.006","article-title":"Bifurcations and chaos in passive dynamic walking: A review","volume":"62","author":"Iqbal","year":"2014","journal-title":"Robot. Auton. Syst."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"1855","DOI":"10.1007\/s10514-019-09839-2","article-title":"Hybrid CPG\u2013FRI dynamic walking algorithm balancing agility and stability control of biped robot","volume":"43","author":"He","year":"2019","journal-title":"Auton. Robots."},{"key":"ref_66","doi-asserted-by":"crossref","unstructured":"Bianchi, R., Akin, H., Ramamoorthy, S., and Sugiura, K. (2015). A comparative study and development of a passive robot with improved stability. RoboCup 2014: Robot World Cup XVIII. RoboCup 2014. Lecture Notes in Computer Science, Springer.","DOI":"10.1007\/978-3-319-18615-3"},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1177\/027836499000900206","article-title":"Passive dynamic walking","volume":"9","author":"McGeer","year":"1990","journal-title":"Int. J. Robot. Res."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"113","DOI":"10.1007\/978-3-642-76693-0_4","article-title":"Principles of walking and running","volume":"11","author":"McGeer","year":"1992","journal-title":"Adv. Comp. Environ. Physiol."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"1061","DOI":"10.1007\/s11071-020-05851-9","article-title":"Stabilization of the passive walking dynamics of the compass-gait biped robot by developing the analytical expression of the controlled Poincar\u00e9 map","volume":"101","author":"Znegui","year":"2020","journal-title":"Nonlinear Dyn."},{"key":"ref_70","unstructured":"Goswami, A., Espiau, B., and Keramane, A. (1996, January 22\u201328). Limit cycles and their stability in a passive bipedal gait. Proceedings of the IEEE International Conference on Robotics and Automation, Minneapolis, MN, USA."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1115\/1.2798313","article-title":"The simplest walking model: Stability, complexity, and scaling","volume":"120","author":"Garcia","year":"1998","journal-title":"J. Biomech. Eng."},{"key":"ref_72","unstructured":"Howell, G.W., and Baillieul, J. (1998, January 18). Simple controllable walking mechanisms which exhibit bifurcations. Proceedings of the 37th IEEE Conference on Decision and Control, Tampa, FL, USA."},{"key":"ref_73","unstructured":"Uchida, K., and Furuta, K. (2000, January 27). Constant torque walking. Proceedings of the 2000 IEEE International Conference on Control Applications, Anchorrage, AK, USA."},{"key":"ref_74","unstructured":"Osuka, K., Fujitani, T., and Ono, T. (1999, January 22\u201327). Passive walking robot QUARTET. Proceedings of the 1999 IEEE International Conference on Control Applications, Kohala Coast, HI, USA."},{"key":"ref_75","doi-asserted-by":"crossref","unstructured":"Asano, F., and Zhi-Wei, L. (2009, January 12\u201317). On efficiency and optimality of asymmetric dynamic bipedal gait. Proceedings of the IEEE International Conference on Robotics and Automation, Kobe, Japan.","DOI":"10.1109\/ROBOT.2009.5152322"},{"key":"ref_76","doi-asserted-by":"crossref","unstructured":"Asano, F. (2009, January 10\u201315). Efficiency analysis of 2-period dynamic bipdal gaits. Proceedings of the IEEE\/RSJ International Conference on Intelligent Robots and Systems, St. Louis, MO, USA.","DOI":"10.1109\/IROS.2009.5354735"},{"key":"ref_77","unstructured":"Kajita, S., Kanehiro, F., Kaneko, K., Fujiwara, K., Harada, K., Yokoi, K., and Hirukawa, H. (2003, January 14\u201319). Biped walking pattern generation by using preview control of zero-moment point. Proceedings of the IEEE International Conference on Robotics and Automation, Taipei, Taiwan."},{"key":"ref_78","doi-asserted-by":"crossref","unstructured":"Yin, Y., and Hosoe, S. (2007, January 9\u201315). Mixed Logic dynamical modeling and on line optimal control of biped robot. Proceedings of the 2006 IEEE\/RSJ International Conference on Intelligent Robots and Systems, Beijing, China.","DOI":"10.5772\/4810"},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"199","DOI":"10.3182\/20020721-6-ES-1901.00845","article-title":"On line optimal control for biped robots","volume":"35","author":"Azevedo","year":"2002","journal-title":"IFAC Proc. Vol."},{"key":"ref_80","doi-asserted-by":"crossref","unstructured":"Wieber, P.-B. (2006, January 4\u20136). Trajectory free linear model predictive control for stable walking in the presence of strong perturbations. Proceedings of the 2006 6th IEEE-RAS International Conference on Humanoid Robots, Genova, Italy.","DOI":"10.1109\/ICHR.2006.321375"},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"1171","DOI":"10.1109\/TRO.2019.2958483","article-title":"MPC for humanoid gait generation: Stability and feasibility","volume":"36","author":"Scianca","year":"2020","journal-title":"IEEE Trans. Robot."},{"key":"ref_82","unstructured":"Venkatesan, K.P., Mahendrakar, P.R., and Mohan, R. (2020, January 12\u201315). Solving Inverse Kinematics using Geometric Analysis for Gait Generation in Small-Sized Humanoid Robots. Proceedings of the 2020 IEEE\/SICE International Symposium on System Integration (SII), Honolulu, HI, USA."},{"key":"ref_83","doi-asserted-by":"crossref","unstructured":"Vundavilli, P.R., and Pratihar, D.K. (2010). Gait planning of biped robots using soft computing: An attempt to incorporate intelligence. Intelligent Autonomous Systems, Springer.","DOI":"10.1007\/978-3-642-11676-6_4"},{"key":"ref_84","unstructured":"Zheng, Y.-F. (1990, January 3\u20136). A neural gait synthesizer for autonomous biped robots. Proceedings of the IEEE International Workshop on Intelligent Robots and Systems, Towards a New Frontier of Applications, Ibaraki, Japan."},{"key":"ref_85","unstructured":"Sugihara, T. (2004). Mobility Enhancement Control of Humanoid Robot Based on Reaction Force Manipulation via Whole Body Motion. [Ph.D. Thesis, University of Tokyo]."},{"key":"ref_86","unstructured":"Y\u00fcksel, B. (2008). Towards the Enhancement of Biped Locomotion and Control Techniques. [Ph.D. Thesis, The Graduate School of Natural and Applied Sciences of Middle East Technical University]."},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1016\/0031-0182(82)90005-0","article-title":"Speeds and gaits of dinosaurs","volume":"38","author":"Thulborn","year":"1982","journal-title":"Palaeogeogr. Palaeoclimatol. Palaeoecol."},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1177\/027836498400300205","article-title":"The gaits of bipedal and quadrupedal animals","volume":"3","author":"Alexander","year":"1984","journal-title":"Int. J. Robot. Reearch"},{"key":"ref_89","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1111\/j.0021-8782.2004.00289.x","article-title":"Bipedal animals, and their differences from humans","volume":"204","author":"Alexander","year":"2004","journal-title":"J. Anat."},{"key":"ref_90","doi-asserted-by":"crossref","unstructured":"Abourachid, A., and Hugel, V. (2016, January 19\u201322). The natural bipeds, birds and humans: An inspiration for bipedal robots. Proceedings of the 5th International Conference, Living Machines, Edinburgh, UK.","DOI":"10.1007\/978-3-319-42417-0_1"},{"key":"ref_91","first-page":"884","article-title":"Understanding the agility of running birds: Sensorimotor and mechanical factors in avian bipedal locomotion","volume":"58","author":"Daley","year":"2018","journal-title":"Integr. Comp. Biol."},{"key":"ref_92","doi-asserted-by":"crossref","first-page":"jeb152538","DOI":"10.1242\/jeb.152538","article-title":"Scaling of avian bipedal locomotion reveals independent effects of body mass and leg posture on gait","volume":"221","author":"Daley","year":"2018","journal-title":"J. Exp. Biol."},{"key":"ref_93","first-page":"49","article-title":"Biped walking robots created at Waseda University: WL and WABIAN family","volume":"365","author":"Lim","year":"2006","journal-title":"Philos. Trans. R. Soc. Math. Phys. Eng. Sci."},{"key":"ref_94","unstructured":"(2021, January 15). HRP-2 Robot. Available online: https:\/\/robots.ieee.org\/robots\/hrp2\/."},{"key":"ref_95","unstructured":"(2021, January 15). iCub Robot. Available online: https:\/\/robots.ieee.org\/robots\/icub\/."},{"key":"ref_96","doi-asserted-by":"crossref","unstructured":"Gouaillier, D., Hugel, V., Blaz, P., Kilner, C., Monceaux, J., Lafourcade, P., Marnier, B., Serre, J., and Maisonnier, B. (2009, January 12\u201317). Mechatronic design of NAO humanoid. Proceedings of the 2009 IEEE InternationalConference on Robotics and Automation, Kobe, Japan.","DOI":"10.1109\/ROBOT.2009.5152516"},{"key":"ref_97","unstructured":"(2021, January 15). HRP-4C. Available online: https:\/\/robots.ieee.org\/robots\/hrp4c\/."},{"key":"ref_98","unstructured":"(2021, January 15). HRP-4. Available online: https:\/\/robots.ieee.org\/robots\/hrp4\/."},{"key":"ref_99","doi-asserted-by":"crossref","first-page":"372","DOI":"10.7210\/jrsj.30.372","article-title":"Petman: A humanoid robot for testing chemical protective clothing","volume":"30","author":"Nelson","year":"2012","journal-title":"J. RoboSoc. Jpn."},{"key":"ref_100","unstructured":"(2021, January 15). REEM-C. Available online: https:\/\/robots.ieee.org\/robots\/reemc\/."},{"key":"ref_101","unstructured":"Debiut of Atlas Robot (2020, August 19). DARPA. Available online: https:\/\/www.darpa.mil\/about-us\/timeline\/debut-atlas-robot."},{"key":"ref_102","doi-asserted-by":"crossref","first-page":"34","DOI":"10.1109\/MSPEC.2019.8913831","article-title":"By leaps and bounds: An exclusive look at how boston dynamics is redefining robot agility","volume":"56","author":"Guizzo","year":"2019","journal-title":"IEEE Spectr."},{"key":"ref_103","unstructured":"(2020, February 08). Boston Dynamics\u2019 Atlas Robot Now Does Gymnastics, Too. Available online: https:\/\/www.youtube.com\/watch?v=kq6mJOktIvM."},{"key":"ref_104","unstructured":"(2021, January 30). Robonaut Leg in Motion. Available online: https:\/\/www.youtube.com\/watch?v=12iayXdNTdM."},{"key":"ref_105","doi-asserted-by":"crossref","unstructured":"Englsberger, J., Werner, A., Ott, C., Henze, B., Roa, M.A., Garofalo, G., Burger, R., Beyer, A., Eiberger, O., and Schmid, K. (2014, January 18\u201320). Overview of the torque-controlled humanoid robot TORO. Proceedings of the 2014 IEEE-RAS International Conference on Humanoid Robots, Madrid, Spain.","DOI":"10.1109\/HUMANOIDS.2014.7041473"},{"key":"ref_106","unstructured":"(2021, August 30). Robotic Ostrich to the Rescue. Available online: https:\/\/www.audubon.org\/news\/robotic-ostrich-rescue."},{"key":"ref_107","unstructured":"(2021, January 30). WALK-MAN Team Built Brand New, Highly Custom Robot for DRC Finals\u2014(2015). Available online: https:\/\/spectrum.ieee.org\/walkman-humanoid-robot-iit."},{"key":"ref_108","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1002\/rob.21569","article-title":"CHIMP, the CMU highly intelligent mobile platform","volume":"32","author":"Stentz","year":"2015","journal-title":"J. Field Robot."},{"key":"ref_109","doi-asserted-by":"crossref","unstructured":"Kim, S., Kim, M., Lee, J., Hwang, S., Chae, J., Park, B., Cho, H., Sim, J., Jung, J., and Lee, H. (2015, January 3\u20135). Approach of team SNU to the DARPA robotics challenge finals. Proceedings of the 2015 IEEE-RAS 15th International Conference on Humanoid Robots (Humanoids), Seoul, Korea.","DOI":"10.1109\/HUMANOIDS.2015.7363458"},{"key":"ref_110","unstructured":"(2021, July 30). THORMANG Robot. Available online: https:\/\/youtu.be\/B9myJuyoibM."},{"key":"ref_111","doi-asserted-by":"crossref","first-page":"397","DOI":"10.1002\/rob.21560","article-title":"Valkyrie: NASA\u2019s first bipedal humanoid robot","volume":"32","author":"Radford","year":"2015","journal-title":"J. Field Robot."},{"key":"ref_112","unstructured":"(2021, January 15). DRC-HUBO+. Available online: https:\/\/robots.ieee.org\/robots\/drchubo\/."},{"key":"ref_113","unstructured":"(2022, January 15). DURUS: SRI\u2019s Ultra-Efficient Walking Humanoid Robot. Available online: https:\/\/spectrum.ieee.org\/durus-sri-ultra-efficient-humanoid-robot."},{"key":"ref_114","unstructured":"(2022, January 15). SRI\u2019S DURUS. Available online: https:\/\/www.youtube.com\/watch?v=HyqT9Bdamt8."},{"key":"ref_115","doi-asserted-by":"crossref","unstructured":"Wu, L., Larkin, M., Potnuru, A., and Tadesse, Y. (2016). HBS-1: A Modular Child-Size 3D Printed Humanoid. Robotics, 5.","DOI":"10.3390\/robotics5010001"},{"key":"ref_116","doi-asserted-by":"crossref","unstructured":"Asano, Y., Kozuki, T., Ookubo, S., Kawamura, M., Nakashima, S., Katayama, T., Yanokura, I., Hirose, T., Kawaharazuka, K., and Makino, S. (2016, January 15\u201317). Human mimetic musculoskeletal humanoid Kengoro toward real world physically interactive actions. Proceedings of the 2016 IEEE-RAS 16th International Conference on Humanoid Robots (Humanoids), Cancun, Mexico.","DOI":"10.1109\/HUMANOIDS.2016.7803376"},{"key":"ref_117","doi-asserted-by":"crossref","unstructured":"Kaminaga, H., Ko, T., Masumura, R., Komagata, M., Sato, S., Yorita, S., and Nakamura, Y. (2016). Mechanism and control of whole-body electro-hydrostatic actuator driven humanoid robot hydra. International Symposium on Experimental Robotics, Springer.","DOI":"10.1007\/978-3-319-50115-4_57"},{"key":"ref_118","unstructured":"(2021, January 15). Cassie. Available online: https:\/\/robots.ieee.org\/robots\/cassie\/."},{"key":"ref_119","doi-asserted-by":"crossref","unstructured":"Ficht, G., Allgeuer, P., Farazi, H., and Behnke, S. (2017, January 15\u201317). NimbRo-OP2: Grown-up 3D printed open humanoid platform for research. Proceedings of the 2017 IEEE-RAS 17th International Conference on Humanoid Robotics (Humanoids), Birmingham, UK.","DOI":"10.1109\/HUMANOIDS.2017.8246944"},{"key":"ref_120","unstructured":"(2021, August 15). TALOS. Available online: https:\/\/robots.ieee.org\/robots\/talos."},{"key":"ref_121","unstructured":"(2021, January 15). HRP-5P. Available online: https:\/\/robots.ieee.org\/robots\/hrp5p\/."},{"key":"ref_122","unstructured":"(2021, January 15). Digit. Available online: https:\/\/robots.ieee.org\/robots\/digit\/."},{"key":"ref_123","doi-asserted-by":"crossref","first-page":"959","DOI":"10.1109\/TRO.2020.2969017","article-title":"Achieving Versatile Energy Efficiency With the WANDERER Biped Robot","volume":"36","author":"Hobart","year":"2020","journal-title":"IEEE Trans. Robot."},{"key":"ref_124","unstructured":"(2022, January 15). WANDERER. Available online: https:\/\/www.youtube.com\/watch?v=tIm0muIOc5E."},{"key":"ref_125","unstructured":"Ha, I., Tamura, Y., Asama, H., Han., H., and Hong, D.W. (2011, January 13\u201318). Development of open humanoid platform DARwIn-OP. Proceedings of the SICE Annual Conference (SICE), Tokyo, Japan."},{"key":"ref_126","unstructured":"Lapeyre, M., Rouanet, P., Grizou, J., N\u2019Guyen, S., Depraetre, F., Falher, A.L., and Oudeyer, P. (2014). Poppy Project: Open-Source Fabrication of 3D Printed Humanoid Robot for Science, Education and Art, Digital Intelligence."},{"key":"ref_127","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1016\/j.proeng.2012.07.136","article-title":"The locomotion of bipedal walking robot with six degree of freedom","volume":"41","author":"Lim","year":"2012","journal-title":"Procedia Eng."},{"key":"ref_128","unstructured":"(2020, August 19). RQ HUNO. Available online: https:\/\/www.robobuilder.net\/rq-huno."},{"key":"ref_129","unstructured":"(2020, September 01). Red Dragon V3. Available online: https:\/\/www.robotshop.com\/community\/forum\/t\/red-dragon-v3\/5340."},{"key":"ref_130","unstructured":"(2020, September 01). w00dBob\u2014A Biped Wooden Robot Made with Arduino Nano. Available online: https:\/\/blog.adafruit.com\/2014\/03\/29\/w00dbob-a-biped-wooden-robot-made-with-arduino-nano-arduinod14\/."},{"key":"ref_131","doi-asserted-by":"crossref","first-page":"477","DOI":"10.4028\/www.scientific.net\/AMM.772.477","article-title":"3D printed biped walking robot","volume":"772","author":"Mikolajczyk","year":"2015","journal-title":"Appl. Mech. Mater."},{"key":"ref_132","doi-asserted-by":"crossref","first-page":"21","DOI":"10.4028\/www.scientific.net\/AMM.613.21","article-title":"Prototype model of walking robot","volume":"613","author":"Mikolajczyk","year":"2014","journal-title":"Appl. Mech. Mater."},{"key":"ref_133","doi-asserted-by":"crossref","first-page":"232","DOI":"10.4028\/www.scientific.net\/AMM.555.232","article-title":"New solution of Walking Robot","volume":"555","author":"Mikolajczyk","year":"2014","journal-title":"Appl. Mech. Mater."},{"key":"ref_134","unstructured":"(2021, December 16). 4DOF Robot. Available online: https:\/\/youtu.be\/yhWYoV3waG0."},{"key":"ref_135","unstructured":"Wang, K., Shah, A., and Kormushev, P. (2018, January 25\u201327). SLIDER: A Novel Bipedal Walking Robot without Knees. Proceedings of the 19th International Conference towards Autonomous Robotic Systems (TAROS 2018), Bristol, UK."},{"key":"ref_136","unstructured":"(2020, August 29). Slider Walking Robott Imperial College Robot Intelligence Lab. Available online: https:\/\/www.youtube.com\/watch?v=DeFMWLdCYng."},{"key":"ref_137","doi-asserted-by":"crossref","first-page":"eabf8136","DOI":"10.1126\/scirobotics.abf8136","article-title":"A bipedal walking robot that can fly, slackline, and skateboard","volume":"6","author":"Kim","year":"2021","journal-title":"Sci. Robot."},{"key":"ref_138","unstructured":"(2022, March 01). Meet Leo, a Robot with Multiple Skills. Available online: https:\/\/www.youtube.com\/watch?v=xI6IGkrLjho."},{"key":"ref_139","unstructured":"(2022, March 01). U-M First in Line For New Bird-Inspired Walking Robot. Available online: https:\/\/news.umich.edu\/u-m-first-in-line-for-new-bird-inspired-walking-robot\/."},{"key":"ref_140","doi-asserted-by":"crossref","first-page":"449","DOI":"10.3233\/THC-1999-7611","article-title":"Towards applicable ballistic walking","volume":"7","year":"1999","journal-title":"Technol. Health Care"},{"key":"ref_141","doi-asserted-by":"crossref","first-page":"1533","DOI":"10.1007\/s11071-016-2777-2","article-title":"Gait optimization and energetics of ballistic walking for an underactuated biped with knees","volume":"85","author":"Moon","year":"2016","journal-title":"Nonlinear Dyn."},{"key":"ref_142","doi-asserted-by":"crossref","unstructured":"Darici, O., Temeltas, H., and Kuo, A.D. (2018). Optimal regulation of bipedal walking speed despite an unexpected bump in the road. PLoS ONE, 13.","DOI":"10.1371\/journal.pone.0204205"},{"key":"ref_143","doi-asserted-by":"crossref","first-page":"4531","DOI":"10.1109\/LRA.2019.2933766","article-title":"A Robustness analysis of inverse optimal control of bipedal walking","volume":"4","author":"Rebula","year":"2019","journal-title":"IEEE Robot. Autom. Lett."},{"key":"ref_144","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1007\/s00422-004-0531-1","article-title":"Modeling of a bipedal robot using mutually coupled Rayleigh oscillators","volume":"92","author":"Filho","year":"2005","journal-title":"Biol. Cybern."},{"key":"ref_145","doi-asserted-by":"crossref","unstructured":"Luo, Q., Pan, C., and Wu, G. (2020). Central pattern generator\u2013based coupling control method for synchronously controlling the two-degrees-of-freedom robot. Sci. Prog., 103.","DOI":"10.1177\/0036850419877731"},{"key":"ref_146","doi-asserted-by":"crossref","first-page":"4925","DOI":"10.3390\/s150304925","article-title":"Sensor data fusion for body state estimation in a bipedal robot and its feedback control application for stable walking","volume":"15","author":"Chen","year":"2015","journal-title":"Sensors"},{"key":"ref_147","doi-asserted-by":"crossref","first-page":"046011","DOI":"10.1088\/1741-2560\/9\/4\/046011","article-title":"A physical model of sensorimotor interactions during locomotion","volume":"9","author":"Klein","year":"2012","journal-title":"J. Neural Eng."},{"key":"ref_148","unstructured":"Forner-Cordero, M., Ackermann, A., and de Lima Freitas, M. (September, January 30). A method to simulate motor control strategies to recover from perturbations: Application to a stumble recovery during gait. Proceedings of the International Conference of the IEEE Engineering in Medicine and Biology Society, Boston, MA, USA."},{"key":"ref_149","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0966-6362(02)00069-3","article-title":"Biomechanics and muscle coordination of human walking: Part II: Lessons from dynamical simulations and clinical implications","volume":"17","author":"Zajac","year":"2003","journal-title":"Gait Posture"},{"key":"ref_150","doi-asserted-by":"crossref","first-page":"207","DOI":"10.7888\/juoeh.31.207","article-title":"Walking assist robot and its clinical application","volume":"31","author":"Kakou","year":"2009","journal-title":"J. UOEH"},{"key":"ref_151","doi-asserted-by":"crossref","unstructured":"Cifuentes, C.A., and Frizera, A. (2016). Human-Robot Interaction Strategies for Walker-Assisted Locomotion, Springer.","DOI":"10.1007\/978-3-319-34063-0"},{"key":"ref_152","unstructured":"Takahashi, R., and Hosoda, K. (2022, May 27). Reflex-Based Walking Controller for Real Bipedal Robot\u2014From Phase-Based to Reflex-Based. 2019. Available online: https:\/\/infoscience.epfl.ch\/record\/272162\/files\/Extended%20abstract.pdf."},{"key":"ref_153","doi-asserted-by":"crossref","first-page":"1156","DOI":"10.1162\/neco.2006.18.5.1156","article-title":"A reflexive neural network for dynamic biped walking control","volume":"18","author":"Geng","year":"2006","journal-title":"Neural Comput."},{"key":"ref_154","doi-asserted-by":"crossref","unstructured":"Pfeiffer, F., and Zielinska, T. (2004). Technological aspects of walking. Walking: Biological and Technological Aspects, Springer Verlag Wien GmbH.","DOI":"10.1007\/978-3-7091-2772-8"},{"key":"ref_155","doi-asserted-by":"crossref","first-page":"175","DOI":"10.1007\/s12555-013-0519-5","article-title":"Sensor Information Analysis for a Humanoid Robot","volume":"13","author":"Sooyong","year":"2015","journal-title":"Int. J. Control Autom. Syst."},{"key":"ref_156","doi-asserted-by":"crossref","first-page":"1039","DOI":"10.1163\/1568553042674699","article-title":"Sensor system of a small biped entertainment robot","volume":"18","author":"Ishida","year":"2004","journal-title":"Adv. Robot."},{"key":"ref_157","doi-asserted-by":"crossref","first-page":"969","DOI":"10.1163\/156855303322554382","article-title":"A review on vision-based control of robot manipulators","volume":"17","author":"Hashimoto","year":"2003","journal-title":"Adv. Robot."},{"key":"ref_158","doi-asserted-by":"crossref","first-page":"103834","DOI":"10.1016\/j.robot.2021.103834","article-title":"A literature review of sensor heads for humanoid robots","volume":"143","year":"2021","journal-title":"Robot. Auton. Syst."},{"key":"ref_159","doi-asserted-by":"crossref","unstructured":"Goswami, A., and Vadakkepat, P. (2019). The PETMAN and atlas robots at boston dynamics. Humanoid Robotics: A Reference, Springer.","DOI":"10.1007\/978-94-007-6046-2"},{"key":"ref_160","doi-asserted-by":"crossref","unstructured":"Fall\u00f3n, M.F., Antone, M., Roy, N., and Teller, S. (2014, January 18\u201320). Drift-free humanoid state estimation fusing kinematic, inertial and LIDAR sensing. Proceedings of the 2014 IEEE-RAS International Conference on Humanoid Robots, Madrid, Spain.","DOI":"10.1109\/HUMANOIDS.2014.7041346"},{"key":"ref_161","doi-asserted-by":"crossref","unstructured":"Fallon, M.F., Marion, P., Deits, R., Whelan, T., Antone, M., McDonald, J., and Tedrake, R. (2015, January 3\u20135). Continuous humanoid locomotion over uneven terrain using stereo fusion. Proceedings of the 2015 IEEE-RAS 15th International Conference on Humanoid Robots (Humanoids), Seoul, Korea.","DOI":"10.1109\/HUMANOIDS.2015.7363465"},{"key":"ref_162","doi-asserted-by":"crossref","unstructured":"Piperakis, S., Kanoulas, D., Tsagarakis, N.G., and Trahanias, P. (2019, January 3\u20138). Outlier-robust state estimation for humanoid robots. Proceedings of the 2019 IEEE\/RSJ International Conference on Intelligent Robots and Systems (IROS), Macau, China.","DOI":"10.1109\/IROS40897.2019.8968152"},{"key":"ref_163","doi-asserted-by":"crossref","first-page":"68","DOI":"10.3389\/frobt.2020.00068","article-title":"Multi-Sensor State Estimator for Legged Robots in Real-World Scenarios","volume":"7","author":"Camurri","year":"2020","journal-title":"Front. Robot. AI"},{"key":"ref_164","doi-asserted-by":"crossref","first-page":"eaar7650","DOI":"10.1126\/scirobotics.aar7650","article-title":"The grand challenges of science robotics","volume":"3","author":"Yang","year":"2018","journal-title":"Sci. Robot."},{"key":"ref_165","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1016\/j.est.2017.11.008","article-title":"Lead batteries for utility energy storage: A review","volume":"15","author":"May","year":"2018","journal-title":"J. Energy Storage"},{"key":"ref_166","unstructured":"Great Power Group (2019, December 31). Square Lithium-Ion Cell. Available online: http:\/\/www.greatpower.net\/cplb\/info_159.aspx?itemid=292&cid=25."},{"key":"ref_167","unstructured":"(2022, May 26). Lithium-Ion Battery. Available online: https:\/\/www.cei.washington.edu\/education\/science-of-solar\/battery-technology\/."},{"key":"ref_168","unstructured":"(2022, May 27). Ultra-Light Battery Pack for Walking Robot. Available online: https:\/\/www.cie-solutions.com\/robotics-battery-pack."},{"key":"ref_169","doi-asserted-by":"crossref","first-page":"761","DOI":"10.1177\/0954407013485567","article-title":"A review of current automotive battery technology and future prospects","volume":"227","author":"Drillkens","year":"2013","journal-title":"Proc. Inst. Mech. Eng. Part D J. Automob. Eng."},{"key":"ref_170","unstructured":"Jones, J.L., Bruce, A.S., and Anita, M.F. (1998). Mobile Robots: Inspiration to Implementation, CRC Press."},{"key":"ref_171","unstructured":"(2022, May 27). Hydrogen Cyllindee General Specification. Available online: https:\/\/www.qtww.com\/wp-content\/uploads\/2019\/01\/H2-Tank-Specifications-Sept-2021-All-Tanks.pdf."},{"key":"ref_172","unstructured":"(2022, May 27). This Star Wars-Inspired Walking Robot Weighs Two Tonnesand Travels at Less Than 1 Mph. Available online: https:\/\/www.guinnessworldrecords.com\/news\/2018\/9\/video-this-star-wars-inspired-walking-robot-weighs-two-tonnes-and-travels-at-les-540955."},{"key":"ref_173","doi-asserted-by":"crossref","unstructured":"Amiryar, M.E., and Keith, R.P. (2017). A review of flywheel energy storage system technologies and their applications. Appl. Sci., 7.","DOI":"10.3390\/app7030286"},{"key":"ref_174","unstructured":"(2022, May 27). BigDog\u2014The Most Advanced Rough-Terrain Robot on Earth. Boston Dynamics. Available online: https:\/\/web.archive.org\/web\/20170518204101\/http:\/www.bostondynamics.com\/robot_bigdog.html."},{"key":"ref_175","doi-asserted-by":"crossref","unstructured":"Thangavelautham, J., Gallardo, D., Strawser, D., and Dubowsky, S. (2011). Hybrid fuel cell power for long duration robot missions in field environments. Field Robotics, World Scientific.","DOI":"10.1142\/9789814374286_0055"},{"key":"ref_176","unstructured":"(2022, May 26). RoBeetle: A Micro Robot Powered by Liquid Fuel. Available online: https:\/\/www.youtube.com\/watch?v=vd6tN19wilQ."},{"key":"ref_177","unstructured":"(2022, May 27). Can Photovoltaics Power Humanoid Robots?. Available online: https:\/\/www.azorobotics.com\/Article.aspx?ArticleID=328."},{"key":"ref_178","unstructured":"(2022, May 22). Robotics\u2014Power Source for Robots, 2013. Available online: https:\/\/www.azorobotics.com\/Article.aspx?ArticleID=139."},{"key":"ref_179","unstructured":"(2022, May 27). Meet Tertill. Available online: https:\/\/www.youtube.com\/watch?v=VwTWhMbnq9g."},{"key":"ref_180","unstructured":"(2022, May 27). Vitirover. Available online: https:\/\/www.pv-magazine.com\/2022\/02\/24\/solar-powered-robotic-mower-for-vineyards\/."},{"key":"ref_181","unstructured":"(2022, May 26). Solar Walking Robot. Available online: https:\/\/www.youtube.com\/watch?v=JSGqPvRPWEY."},{"key":"ref_182","unstructured":"(2022, May 26). Future Batteries, Coming Soon: Charge in Seconds, Last Months and Power Over the Air, Mart 2021. Available online: https:\/\/www.pocket-lint.com\/gadgets\/news\/130380-future-batteries-coming-soon-charge-in-seconds-last-months-and-power-over-the-air."},{"key":"ref_183","first-page":"413","article-title":"The energetic cost of moving about: Walking and running are extremely inefficient forms of locomotion. Much greater efficiency is achieved by birds, fish\u2014And bicyclists","volume":"63","author":"Tucker","year":"1975","journal-title":"Am. Sci."},{"key":"ref_184","doi-asserted-by":"crossref","unstructured":"Siciliano, B., and Khatib, O. (2008). Legged robots. Springer Handbook of Robotics, Springer.","DOI":"10.1007\/978-3-540-30301-5"},{"key":"ref_185","unstructured":"Sakagami, Y., Watanabe, R., Aoyama, C., Matsunaga, S., Higaki, N., and Fujimura, K. (October, January 30). The intelligent ASIMO: System overview and integration. Proceedings of the IEEE\/RSJ International Conference on Intelligent Robots and Systems (IEEE), Lausanne, Switzerland."},{"key":"ref_186","doi-asserted-by":"crossref","first-page":"129","DOI":"10.3389\/frobt.2018.00129","article-title":"An overview on principles for energy efficient robot locomotion","volume":"5","author":"Kashiri","year":"2018","journal-title":"Front. Robot. AI"},{"key":"ref_187","doi-asserted-by":"crossref","unstructured":"Reher, J., Cousineau, E.A., Hereid, A., Hubicki, C.M., and Ames, A.D. (2016, January 16\u201321). Realizing dynamic and efficient bipedal locomotion on the humanoid robot DURUS. Proceedings of the 2016 IEEE International Conference on Robotics and Automation (ICRA), Stockholm, Sweden.","DOI":"10.1109\/ICRA.2016.7487325"},{"key":"ref_188","unstructured":"(2022, February 15). Meet Cassie\u2014The Highly Energy Efficient Walking Machine. Available online: https:\/\/www.borntoengineer.com\/meet-cassie-highly-energy-efficient-walking-machine."},{"key":"ref_189","unstructured":"(2021, August 30). Cassie Robot Runs Turf 5k. Available online: https:\/\/www.youtube.com\/watch?v=FSaSjd_HOaI."},{"key":"ref_190","doi-asserted-by":"crossref","first-page":"065002","DOI":"10.1088\/1748-3190\/aa8290","article-title":"A neural network with central pattern generators entrained by sensory feedback controls walking of a bipedal model","volume":"12","author":"Li","year":"2017","journal-title":"Bioinspir. Biomim."},{"key":"ref_191","doi-asserted-by":"crossref","first-page":"046007","DOI":"10.1088\/1748-3190\/abf6b9","article-title":"A novel underwater bipedal walking soft robot bio-inspired by the coconut octopus","volume":"16","author":"Wu","year":"2021","journal-title":"Bioinspir. Biomim."},{"key":"ref_192","doi-asserted-by":"crossref","first-page":"1042","DOI":"10.1098\/rsif.2020.1042","article-title":"Phase transformation-driven artificial muscle mimics the multifunctionality of avian wing muscle","volume":"18","author":"Leal","year":"2021","journal-title":"J. R. Soc. Interface"},{"key":"ref_193","doi-asserted-by":"crossref","first-page":"319","DOI":"10.1016\/j.gaitpost.2021.03.035","article-title":"The puzzle of the walk-to-run transition in humans","volume":"86","author":"Voigt","year":"2021","journal-title":"Gait Posture"},{"key":"ref_194","doi-asserted-by":"crossref","unstructured":"Samani, F., and Ceccarelli, M. (2020, January 19). Prototype design and testing of TORVEastro, cable-driven astronaut robot. Proceedings of theInternational Conference on Robotics in Alpe-Adria Danube Region, Kaiserslautern, Germany.","DOI":"10.1007\/978-3-030-48989-2_48"},{"key":"ref_195","doi-asserted-by":"crossref","first-page":"101008","DOI":"10.1115\/1.4051232","article-title":"A generalized model for compliant passive bipedal walking: Sensitivity analysis and implications on bionic leg design","volume":"143","author":"Smyrli","year":"2021","journal-title":"J. Biomech. 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