{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,9]],"date-time":"2026-07-09T23:55:05Z","timestamp":1783641305734,"version":"3.55.0"},"reference-count":26,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,1]],"date-time":"2025-11-01T00:00:00Z","timestamp":1761955200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001348","name":"Agency for Science, Technology and Research","doi-asserted-by":"publisher","award":["I2001E0067"],"award-info":[{"award-number":["I2001E0067"]}],"id":[{"id":"10.13039\/501100001348","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Schaeffler Hub for Advanced Research at NTU"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>This paper presents the design and testing of a lightweight, low-cost robotic arm with an extended vertical range. The 9-degree-of-freedom (DOF) system comprises a 6-DOF arm and a 3-DOF gripper. To minimize weight, the six wrist and gripper joints are cable-driven, with all actuators relocated to the shoulder assembly. As a result, the wrist and gripper only weigh 222 g and 113 g, respectively, significantly reducing the inertia on the end effector. The arm utilizes a SCARA-configuration that slides along a tower for extended vertical reach. A key innovation is a closed-section frame that attaches the arm to the tower, in which the bending and torsional loads from the payload can be directly transferred onto the static structure. In contrast to conventional design, this design does not require the shoulder motor to take the bending load directly. Instead, the motor only needs to overcome the rolling friction of the reaction load. Experimental results demonstrate that this approach reduces the required motor torque by a factor of 30. Consequently, the prototype can manipulate a 3 kg payload at a 0.5 m lateral reach while weighing only 4.5 kg, costing USD 1200, and consuming a maximum of 11.1 W of power.<\/jats:p>","DOI":"10.3390\/robotics14110161","type":"journal-article","created":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T13:47:58Z","timestamp":1762177678000},"page":"161","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Lightweight and Low-Cost Cable-Driven SCARA Robotic Arm with 9 DOF"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-1529-1603","authenticated-orcid":false,"given":"Yuquan","family":"Shi","sequence":"first","affiliation":[{"name":"School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 639798, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4764-0166","authenticated-orcid":false,"given":"Wai Tuck","family":"Chow","sequence":"additional","affiliation":[{"name":"School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 639798, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4329-274X","authenticated-orcid":false,"given":"Thomas M.","family":"Kwok","sequence":"additional","affiliation":[{"name":"School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 639798, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-2049-6853","authenticated-orcid":false,"given":"Yilong","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Ave, Singapore 639798, Singapore"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,1]]},"reference":[{"key":"ref_1","unstructured":"(2025, October 27). Universal Robots UR3 Robot Arm; Technical Specification; Universal Robots A\/S: Odense, Denmark. Available online: https:\/\/howtorobot.com\/sites\/default\/files\/2021-12\/universal-robot-ur3-technical-spec.pdf."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Tay, S.H., Choong, W.H., and Yoong, H.P. (2022, January 13\u201315). A Review of SCARA Robot Control System. Proceedings of the 2022 IEEE International Conference on Artificial Intelligence in Engineering and Technology (IICAIET), Kota Kinabalu, Malaysia.","DOI":"10.1109\/IICAIET55139.2022.9936755"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Sanjeewa, N., Wathudura, V.M., Kahatapitiya, N.S., Silva, B.N., Subasinghage, K., and Wijesinghe, R.E. (2025). Real-Time Coordinate Estimation for SCARA Robots in PCB Repair Using Vision and Laser Triangulation. Instruments, 9.","DOI":"10.3390\/instruments9020007"},{"key":"ref_4","unstructured":"(2021). SCARA Robot for High Precision Assembly (Standard No. IRB 920T\/IRB 920). Available online: https:\/\/search.abb.com\/library\/Download.aspx?DocumentID=9AKK107992A6817&LanguageCode=en&DocumentPartId=&Action=Launch."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Wang, Y., Zhao, C., Mei, D., Tang, G., Zhang, L., and Zhu, D. (2022). Structural Design and Position Tracking of the Reconfigurable SCARA Robot by the Pre-Filter AFE PID Controller. Appl. Sci., 12.","DOI":"10.3390\/app12031626"},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Suri, S., Jain, A., Verma, N., and Prasertpoj, N. (2018, January 13\u201314). SCARA Industrial Automation Robot. Proceedings of the 2018 International Conference on Power Energy, Environment and Intelligent Control (PEEIC), Greater Noida, India.","DOI":"10.1109\/PEEIC.2018.8665440"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Zhang, Z., Guo, Q., Grigorev, M.A., and Kholodilin, I. (2024). Construction Method of a Digital-Twin Simulation System for SCARA Robots Based on Modular Communication. Sensors, 24.","DOI":"10.3390\/s24227183"},{"key":"ref_8","unstructured":"Haider, A.F.A., Haidar, F.A., and Nandha, K. (2012, January 12\u201313). A Review of Application Industrial Robotic Design. Proceedings of the 2011 Ninth International Conference on ICT and Knowledge Engineering, Bangkok, Thailand."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Song, H., Kim, Y.-S., Yoon, J., Yun, S.-H., Seo, J., and Kim, Y.-J. (2018, January 1\u20135). Development of Low-Inertia High-Stiffness Manipulator LIMS2 for High-Speed Manipulation of Foldable Objects. Proceedings of the 2018 IEEE\/RSJ International Conference on Intelligent Robots and Systems (IROS), Madrid, Spain.","DOI":"10.1109\/IROS.2018.8594005"},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Tanaka, K., and Hamaya, M. (June, January 29). Twist Snake: Plastic Table-Top Cable-Driven Robotic Arm with All Motors Located at the Base Link. Proceedings of the 2023 IEEE International Conference on Robotics and Automation (ICRA), London, UK.","DOI":"10.1109\/ICRA48891.2023.10160995"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Wei, F., Luo, K., Zhang, Y., and Jiang, J. (2024). Structural Design and Kinematic Analysis of Cable-Driven Soft Robot. Actuators, 13.","DOI":"10.3390\/act13120497"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Palmieri, P., Melchiorre, M., and Mauro, S. (2022). Design of a Lightweight and Deployable Soft Robotic Arm. Robotics, 11.","DOI":"10.3390\/robotics11050088"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Nguyen, V.P., Chow, W.T., Dhyan, S.B., Zhang, B., Han, B.S., and Wong, H.Y.A. (2024). Low-Cost Cable-Driven Robot Arm with Low-Inertia Movement and Long-Term Cable Durability. Robotics, 13.","DOI":"10.3390\/robotics13090128"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1177\/1687814018777428","article-title":"Design and Modeling of Motion-Decoupling Mechanism for Cable-Driven Joints","volume":"10","author":"Jiang","year":"2018","journal-title":"Adv. Mech. Eng."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"64932","DOI":"10.1109\/ACCESS.2019.2915363","article-title":"Hybrid Structure Design of Lightweight Robotic Arms Based on Carbon Fiber Reinforced Plastic and Aluminum Alloy","volume":"7","author":"Yin","year":"2019","journal-title":"IEEE Access"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Khozeimeh, M.A., Fotouhi, R., and Moazed, R. (2022). Static and Vibration Analyses of a Composite CFRP Robot Manipulator. J. Compos. Sci., 6.","DOI":"10.3390\/jcs6070196"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"101006","DOI":"10.1115\/1.4064568","article-title":"A Hybrid Method Combining Data-Driven and Model-Based Algorithms for External Force-Sensing and Haptics Control of Cable-Pulley-Driven Surgical Robotic Manipulator","volume":"16","author":"Wang","year":"2024","journal-title":"J. Mech. Robot."},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Zhou, Z., Yang, J., Runciman, M., Avery, J., Sun, Z., and Mylonas, G. (2024). A Tension Sensor Array for Cable-Driven Surgical Robots. Sensors, 24.","DOI":"10.3390\/s24103156"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Nguyen, V.P., Dhyan, S.B., and Chow, W.T. (2024). A Decoupling Module Based on a Geometrical-Balance Mechanism for Mitigating Cable Length Variation in Cable-Driven Applications. Machines, 12.","DOI":"10.3390\/machines12110755"},{"key":"ref_20","unstructured":"Castillo, A., and Chow, W.T. (2025). A028 Cable Actuated Robot Arm. School of Mechanical and Aerospace Engineering, Nanyang Technological University. Undergraduate Report."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Kwok, T.M., Cheng, H.H., and Yu, H. (2023, January 4\u20139). A 2-DOF Elbow Exoskeleton with Spherical Scissor Mechanism for ADL Assistance. Proceedings of the 2023 IEEE International Conference on Robotics and Biomimetics (ROBIO), Koh Samui, Thailand.","DOI":"10.1109\/ROBIO58561.2023.10354535"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Li, R., Liu, Z., Mi, W., Bai, S., and Zhang, J. (2020). Design and Kinematic Analysis of a Novel Wire-Driven Spherical Scissors Mechanism. Recent Advances in Mechanisms, Transmissions and Applications, Springer.","DOI":"10.1007\/978-981-15-0142-5_20"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"119","DOI":"10.1016\/j.mechmachtheory.2015.07.012","article-title":"Design and transmission analysis of an asymmetrical spherical parallel manipulator","volume":"94","author":"Wu","year":"2015","journal-title":"Mech. Mach. Theory"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1806","DOI":"10.1109\/TRO.2021.3070124","article-title":"ABENICS: Active Ball Joint Mechanism with Three-DOF Based on Spherical Gear Meshings","volume":"37","author":"Abe","year":"2021","journal-title":"IEEE Trans. Robot."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Whitney, J.P., and Hodgins, J.K. (June, January 31). A passively safe and gravity-counterbalanced anthropomorphic robot arm. Proceedings of the 2014 IEEE International Conference on Robotics and Automation (ICRA), Hong Kong, China.","DOI":"10.1109\/ICRA.2014.6907768"},{"key":"ref_26","unstructured":"(2025, October 23). Epson T3 SCARA Robots\u2014Support Page (T3-B401S). Available online: https:\/\/epson.com\/Support\/Robots\/SCARA-Robots\/SCARA-T-Series\/Epson-T3-SCARA-Robots\/s\/SPT_RT3-401SS."}],"container-title":["Robotics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2218-6581\/14\/11\/161\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T14:44:09Z","timestamp":1762181049000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2218-6581\/14\/11\/161"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,1]]},"references-count":26,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2025,11]]}},"alternative-id":["robotics14110161"],"URL":"https:\/\/doi.org\/10.3390\/robotics14110161","relation":{},"ISSN":["2218-6581"],"issn-type":[{"value":"2218-6581","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,1]]}}}