{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,4]],"date-time":"2026-05-04T22:31:57Z","timestamp":1777933917198,"version":"3.51.4"},"reference-count":32,"publisher":"SAGE Publications","issue":"1","license":[{"start":{"date-parts":[[2021,2,1]],"date-time":"2021-02-01T00:00:00Z","timestamp":1612137600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Soft Robotics"],"published-print":{"date-parts":[[2021,2,1]]},"abstract":"<jats:p>Given that mobile soft robots are adaptable to the environment, they are always tethered with slow locomotion speed. Compared with other types of mobile robots, mobile soft robots may be more suitable for rescuing tasks, accompanying elderly people, and being used as a safe toy for children. However, the infinite freedom of soft robots increases the difficulty of precision control. In addition, the large volume and long tube of the conventional soft actuator structure limit the range of motion of current mobile soft robots. In this article, a newly designed innovative untethered-bioinspired quadrupedal robot based on double-chamber pre-charged pneumatic (DCPCP) soft actuators with highly flexible trunk is proposed. Asymmetrical cross-tendons actuated by servo motors are used to drive the DCPCP soft legs so that buckling can be avoided and mimic the gait of quadruped animals with the simplest drive and control strategy. In addition, the proposed design greatly improves energy efficiency and exhibits superior performance of variable stiffness. The bioinspired highly flexible trunk is designed with the supporting spine structure and tendon driven muscle to deform, which can constantly adjust to the contact situation between the foot and the ground to adjust the center of gravity of the soft quadruped robot and increase stability when walking and turning. The proposed soft quadruped robot does not require any air compressors, valves, and hoses. The characteristics of untethered, high-energy efficiency, linear control, and stability make the soft quadruped robot suitable for many applications.<\/jats:p>","DOI":"10.1089\/soro.2019.0137","type":"journal-article","created":{"date-parts":[[2020,6,10]],"date-time":"2020-06-10T22:32:39Z","timestamp":1591828359000},"page":"97-108","update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":27,"title":["Untethered-Bioinspired Quadrupedal Robot Based on Double-Chamber Pre-charged Pneumatic Soft Actuators with Highly Flexible Trunk"],"prefix":"10.1177","volume":"8","author":[{"given":"Yujia","family":"Li","sequence":"first","affiliation":[{"name":"College of Nuclear Technology and Automation Engineering, Chengdu University of Technology, Chengdu, China."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tao","family":"Ren","sequence":"additional","affiliation":[{"name":"College of Nuclear Technology and Automation Engineering, Chengdu University of Technology, Chengdu, China."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yunquan","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Hong Kong, Hong Kong, China."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qingyou","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Chengdu University of Technology, Chengdu, China."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yonghua","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Hong Kong, Hong Kong, China."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"179","published-online":{"date-parts":[[2021,2,15]]},"reference":[{"key":"e_1_3_4_2_2","doi-asserted-by":"publisher","DOI":"10.1242\/jeb.202.24.3565"},{"key":"e_1_3_4_3_2","doi-asserted-by":"publisher","DOI":"10.1016\/0021-9290(90)90043-3"},{"key":"e_1_3_4_4_2","doi-asserted-by":"publisher","DOI":"10.3182\/20080706-5-KR-1001.01833"},{"key":"e_1_3_4_5_2","first-page":"10","article-title":"Walking mechanism and gait design of a novel compound quadruped robot","author":"Hong M","year":"2018","unstructured":"Hong M, , Yun-Xia L. Walking mechanism and gait design of a novel compound quadruped robot. In: 2018. 3rd International Conference on Robotics and Automation Engineering (ICRAE), Guangzhou, China, November 17\u201319, 2018, pp. 10\u201313. IEEE.","journal-title":"3rd International Conference on Robotics and Automation Engineering (ICRAE)"},{"key":"e_1_3_4_6_2","doi-asserted-by":"publisher","DOI":"10.1109\/TRO.2012.2235698"},{"key":"e_1_3_4_7_2","doi-asserted-by":"publisher","DOI":"10.1109\/ICRA.2019.8793865"},{"key":"e_1_3_4_8_2","doi-asserted-by":"publisher","DOI":"10.1109\/ICMA.2017.8016030"},{"key":"e_1_3_4_9_2","doi-asserted-by":"publisher","DOI":"10.1109\/ICRA.2013.6631041"},{"key":"e_1_3_4_10_2","doi-asserted-by":"publisher","DOI":"10.1007\/s42235-018-0085-x"},{"key":"e_1_3_4_11_2","volume-title":"et al","author":"Weinmeister K","year":"2015","unstructured":"Weinmeister K, , Eckert P, , Witte H, et al. Cheetah-cub-S: Steering of a quadruped robot using trunk motion. In: 2015 IEEE international symposium on safety, security, and rescue robotics (SSRR), West Lafayette, IN, October 18\u201320, 2015, pp. 1\u20136. IEEE."},{"key":"e_1_3_4_12_2","volume-title":"et al","author":"Cho H","unstructured":"Cho H, , Nishikawa S, , Niiyama R, et al. Dynamic locomotion of quadruped with laterally parallel leaf spring spine. In: International Conference on Climbing and Walking Robots and the Support Technologies for Mobile Machines, Kuala Lumpur, Malaysia, August 26\u201328, 2019, pp. 91\u201398. CLAWAR Association Ltd."},{"key":"e_1_3_4_13_2","unstructured":"Kito Y Sueoka Y Nakanishi D et al. Quadruped passive dynamic walking robot with a new trunk structure inspired by spine. In: Proceedings of Dynamic Walking ETH Zurich Switzerland June 10\u201313 2014."},{"key":"e_1_3_4_14_2","author":"Sabelhaus AP","unstructured":"Sabelhaus AP, , van Vuuren LJ, , Joshi A, et al. Design, simulation, and testing of a flexible actuated spine for quadruped robots. arXiv preprint arXiv 2018;1804.06527.","journal-title":"et al"},{"key":"e_1_3_4_15_2","doi-asserted-by":"publisher","DOI":"10.1126\/scirobotics.aah3690"},{"key":"e_1_3_4_16_2","doi-asserted-by":"publisher","DOI":"10.1098\/rsif.2017.0101"},{"key":"e_1_3_4_17_2","doi-asserted-by":"publisher","DOI":"10.1177\/0278364913498432"},{"key":"e_1_3_4_18_2","doi-asserted-by":"publisher","DOI":"10.1089\/soro.2014.0008"},{"key":"e_1_3_4_19_2","doi-asserted-by":"publisher","DOI":"10.1126\/science.1222149"},{"key":"e_1_3_4_20_2","doi-asserted-by":"publisher","DOI":"10.1088\/1748-3190\/10\/3\/035003"},{"key":"e_1_3_4_21_2","doi-asserted-by":"publisher","DOI":"10.1089\/soro.2016.0001"},{"key":"e_1_3_4_22_2","volume-title":"et al","author":"Drotman D","unstructured":"Drotman D, , Jadhav S, , Karimi M, et al. 3D printed soft actuators for a legged robot capable of navigating unstructured terrain. In: International Conference on Robotics and Automation (ICRA), Singapore, Singapore, May 29\u2013June 3, 2017, pp. 5532\u20135538. IEEE."},{"key":"e_1_3_4_23_2","doi-asserted-by":"publisher","DOI":"10.1115\/DETC2009-86847"},{"key":"e_1_3_4_24_2","volume-title":"et al","author":"Zheng T","unstructured":"Zheng T, , Godage IS, , Branson DT, et al. Octopus inspired walking robot: design, control and experimental validation. In: International Conference on Robotics and Automation, Karlsruhe, Germany, 2013, pp. 816\u2013821. IEEE."},{"key":"e_1_3_4_25_2","volume-title":"et al","author":"Tolley MT","unstructured":"Tolley MT, , Shepherd RF, , Karpelson M, et al. An untethered jumping soft robot. In: IEEE\/RSJ International Conference on Intelligent Robots and Systems, Chicago, IL, September 14, 2014, pp. 561\u2013566. IEEE."},{"key":"e_1_3_4_26_2","doi-asserted-by":"publisher","DOI":"10.1007\/s11432-016-9033-0"},{"key":"e_1_3_4_27_2","first-page":"1748","article-title":"Softworms: The design and control of nonpneumatic, 3D-printed, deformable robots","volume":"11","author":"Umedachi T","year":"2016","unstructured":"Umedachi T, , Vikas V, , Trimmer BA. Softworms: The design and control of nonpneumatic, 3D-printed, deformable robots. Bioinspirat Biomim, 2016; 11:1748\u20133190.","journal-title":"Bioinspirat Biomim"},{"key":"e_1_3_4_28_2","doi-asserted-by":"crossref","unstructured":"Kitamori T Wada A Nabae H et al. Untethered three-arm pneumatic robot using hose-free pneumatic actuator. In: IEEE\/RSJ International Conference on Intelligent Robots and Systems Daejeon South Korea October 9 2016 pp. 543\u2013548. IEEE.","DOI":"10.1109\/IROS.2016.7759106"},{"key":"e_1_3_4_29_2","first-page":"1","volume-title":"Proceedings of International Symposium on Robotics Research, Flagstaff, AZ, USA, August 28\u2013September 1","author":"Onal","year":"2011","unstructured":"Onal. CD, Chen X, Whitesides GM, et al. Soft mobile robots with on-board chemical pressure generation. In: Proceedings of International Symposium on Robotics Research, Flagstaff, AZ, USA, August 28\u2013September 1, 2011, pp. 1\u201316."},{"key":"e_1_3_4_30_2","doi-asserted-by":"publisher","DOI":"10.1038\/nature14543"},{"key":"e_1_3_4_31_2","doi-asserted-by":"publisher","DOI":"10.1089\/soro.2013.0002"},{"key":"e_1_3_4_32_2","doi-asserted-by":"publisher","DOI":"10.1089\/soro.2017.0090"},{"key":"e_1_3_4_33_2","doi-asserted-by":"publisher","DOI":"10.1089\/soro.2019.0008"}],"container-title":["Soft Robotics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.sagepub.com\/doi\/full-xml\/10.1089\/soro.2019.0137","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1089\/soro.2019.0137","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/journals.sagepub.com\/doi\/pdf\/10.1089\/soro.2019.0137","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,2]],"date-time":"2026-05-02T02:04:49Z","timestamp":1777687489000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.sagepub.com\/doi\/10.1089\/soro.2019.0137"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,2,1]]},"references-count":32,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2021,2,1]]}},"alternative-id":["10.1089\/soro.2019.0137"],"URL":"https:\/\/doi.org\/10.1089\/soro.2019.0137","relation":{},"ISSN":["2169-5172","2169-5180"],"issn-type":[{"value":"2169-5172","type":"print"},{"value":"2169-5180","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,2,1]]}}}