Journal
G. C. Thomas, O. Campbell IV, N. Nichols, N. Brissonneau, B. He, J. James, N. Paine, and L. Sentis, “Formulating and Deploying Strength Amplification Controllers for Lower-Body Walking Exoskeletons,” Frontiers in Robotics and AI, vol. 8, pp. 295, Sept. 2021. [pdf] [Frontiers]
R. L. Medrano, G. C. Thomas, E. J. Rouse, R. D. Gregg, “Analysis of the Bayesian Gait-State Estimation Problem for Lower-Limb Wearable Robot Sensor Configurations,” IEEE Robotics and Automation Letters, vol. 7, no. 3, pp. 7463 – 7470, July 2022, doi: 10.1109/LRA.2022.3183790. [IEEE] [pdf]
C. Nesler, G. C. Thomas, N. Divekar, E. J. Rouse, R. D. Gregg, “Enhancing Voluntary Motion with Modular, Backdrivable, Powered Hip and Knee Orthoses,” IEEE Robotics and Automation Letters, vol. 7, no. 3, pp. 6155-6162, July 2022, doi: 10.1109/LRA.2022.3145580. [IEEE] [pdf]
J. Lin, N. V. Divekar, G. C. Thomas, R. D. Gregg, “Optimally Biomimetic Passivity-Based Control of a Lower-Limb Exoskeleton Over the Primary Activities of Daily Life,” IEEE Open Journal of Control Systems, vol. 1, pp. 15 – 28, April 2022, doi: 10.1109/OJCSYS.2022.3165733. [IEEE] [pdf]
R. L. Medrano, G. C. Thomas, E. Rouse, “Can humans perceive the metabolic benefit provided by augmentative exoskeletons?” Journal of NeuroEngineering and Rehabilitation, vol 19, no. 26, February 2022, doi: 10.1186/s12984-022-01002-w [Springer] [pdf]
R. L. Medrano, E. Rouse, G. C. Thomas, “Biological Joint Loading and Exoskeleton Design,” IEEE Transactions on Medical Robotics and Bionics, vol. 3, no. 3, pp. 847-851, Aug. 2021. [IEEE] [pdf] [CodeOcean]
N. Brissonneau, B. He, G. C. Thomas, and L. Sentis, “Biologically-Inspired Impedance Control with Hysteretic Damping,” IEEE Control Systems Letters, vol. 5, no. 5, pp. 1717-1722, Nov. 2021. (early access) [IEEE] [pdf]
G. C. Thomas, J. Mehling, J. Holley, and L. Sentis, “Phase-Relaxed-Passive Full State Feedback Gain Limits for Series Elastic Actuators,” IEEE/ASME Transactions on Mechatronics, vo. 26, no. 1, pp. 586-591, Feb. 2021. [IEEE] [pdf]
B. He, H. Huang, G. C. Thomas, and L. Sentis, “A Complex Stiffness Human Impedance Model with Customizable Exoskeleton Control,” IEEE Transactions on Neural Systems and Rehabilitation Engineering, vol. 28, no. 11, pp. 2468-2477, Nov. 2020. [ArXiv] [IEEE]
G. C. Thomas, and L. Sentis, “Quadric Inclusion Programs: an LMI Approach to H[infinity]-Model Identification,” IEEE Transactions on Automatic Control, vol. 64, no. 10, pp. 4229-4236, Oct. 2019. [doi] [IEEE] [CodeOcean] [ArXiv]
K. Isik, G. C. Thomas, and L. Sentis, “A Fixed Structure Gain Selection Strategy for High Impedance Series Elastic Actuator Behavior,” Journal of Dynamic Systems, Measurement, and Control, vol. 141, no. 2, Oct. 2018, doi: 10.1115/1.4041449. [ASME]
D. Kim, Y. Zhao, G. C. Thomas, and L. Sentis, “Stabilizing Series-Elastic Point-Foot Bipeds Using Whole-Body Operational Space Control,” IEEE Transactions on Robotics, vol. 32, no. 6, pp. 1362-1379, Dec. 2016. [Finalist, Best WBC Paper 2016][Finalist, Best WBC-Video 2016][doi][IEEE][pdf]
T. Koolen, S. Bertrand, G. C. Thomas, T. de Boer, T. Wu, J. Smith, J. Englsberger, and J. E. Pratt, “Design of a Momentum-Based Control Framework and Application to the Humanoid Robot Atlas,” International Journal of Humanoid Robotics, vol. 13, no. 1, pp. 1650007, Mar. 2016. [Winner, IJHR 2016 Best Paper Awards][Finalist, Best WBC Paper 2016][IJHR]
Conference
G. C. Thomas, R. D. Gregg, “An Energy Shaping Exoskeleton Controller for Human Strength Amplification,” in The 2021 IEEE Conference on Decision and Control, pp. 1419-1425, doi: 10.1109/CDC45484.2021.9682793 [pdf] [IEEE]
E. Bolívar-Nieto, G. C. Thomas, E. Rouse, R. D. Gregg, “Convex Optimization for Spring Design in Series Elastic Actuators: From Theory to Practice,” in the 2021 IEEE/RSJ International Conference on Intelligent Robotics and Systems, pp. 9327-9332, 2021. [pdf]
R. Medrano, G. C. Thomas, and E. Rouse. “Methods for Measuring the Just Noticeable Difference for Variable Stimuli: Implications for Perception of Metabolic Rate with Exoskeleton Assistance.” in The 8th IEEE RAS/EMBS International Conference for Biomedical Robotics and Biomechatronics, pp. 483-490, New York City, NY, 2020. [IEEE]
B. He, G. C. Thomas, and L. Sentis. “Robust Estimator-Based Safety Verification: A Vector Norm Approach.” In The 2020 American Control Conference, pp. 3419-3424. [ArXiv] [IEEE]
H. Huang, H. Cappel, G. C. Thomas, B. He, and L. Sentis. “Adaptive Compliance Shaping with Human Impedance Estimation.” In The 2020 American Control Conference, pp. 3419-3424. [ArXiv] [IEEE]
G. C. Thomas, J. M. Coholich, and L. Sentis. “Compliance Shaping for Control of Strength Amplification Exoskeletons with Elastic Cuffs.” Presented at The 2019 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, Hong Kong, China, pp. 1199-1206. IEEE, 2019. [IEEE] [ArXiv]
B. He, H. Huang, G. C. Thomas, and L. Sentis. “Complex Stiffness Model of Physical Human-Robot Interaction: Implications for Control of Performance Augmentation Exoskeletons.” In The 2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Macau, China, pp. 6748-6755. IEEE, 2019. [IEEE] [doi] [ArXiv]
B. He, G. C. Thomas, N. A. Paine, and L. Sentis. “Modeling and Loop Shaping of Single-Joint Amplification Exoskeleton with Contact Sensing and Series Elastic Actuation.” In The 2019 American Control Conference, Philadelphia, PA, pp. 4580-4587. IEEE, 2019. [IEEE] [ArXiv]
R. Schlossman, G. C. Thomas, O. Campbell, and L. Sentis, “Toward Exploiting the Natural Dynamics of Series Elastic Robots by Actuator-Centered Sequential Linear Program,” The IEEE International Conference on Robotics and Biomimetics, Kuala Lumpur, Malaysia, 2018 [IEEE] [ArXiv]
G. C. Thomas, B. He, and L. Sentis, “Safety Control Synthesis with Input Limits: a Hybrid Approach,” The American Control Conference, Milwaukee, WI, 2018 [IEEE] [ArXiv]
G. C. Thomas, and L. Sentis, “MIMO Identification of Frequency-Domain Unreliability in SEAs,” The American Control Conference, Seattle, WA, 2017 [IEEE][pdf]
P. Rao, G. C. Thomas, L. Sentis, and A. Deshpande “Analyzing Achievable Stiffness Control Bounds of Robotic Hands With Coupled Finger Joints,” IEEE Conference on Robotics and Automation, Singapore, 2017 [Winner, Best ICRA 2017 Manipulation Paper] [IEEE] [pdf]
G. C. Thomas, and L. Sentis, “Towards Computationally Efficient Planning of Dynamic Multi-Contact Locomotion,” in The IEEE/RSJ International Conference on Intelligent Robots and Systems, Daejeon, South Korea, 2016, doi: 10.1109/IROS.2016.7759571 [IEEE] [pdf]
D. Kim, G. C. Thomas, and L. Sentis, “A Method for Dynamically Balancing a Point Foot Robot,” in The 15th IEEE-RAS International Conference on Humanoid Robots, 2015, doi: 10.1109/HUMANOIDS.2015.7363468 [IEEE] [pdf]
D. Kim, G. C. Thomas, and L. Sentis, “Continuous Cyclic Stepping on 3D Point-Foot Biped Robots Via Constant Time to Velocity Reversal,” in Control Automation Robotics & Vision (ICARCV), 2014 13th International Conference on., IEEE. 2014, doi: 10.1109/ICARCV.2014.7064561 [IEEE]
D. Kim, Y. Zhao, G. C. Thomas, and L. Sentis, “Empirical Modifications to a Phase Space Planner which Compensates for Low Stiffness Actuation in a Planar, Point-Foot, Biped Robot,” in ASME 2014 Dynamics Systems and Control Conference, San Antonio, TX, 2014, doi: 10.1115/DSCC2014-6033 [ASME]
K.S. Kim, G. C. Thomas, and L. Sentis, “Fully Omnidirectional Compliance in Mobile Robots Via Drive-Torque Sensor Feedback” in IEEE International Conference of Intelligent Robots and Systems, 2014, doi: 10.1109/IROS.2014.6943239 [IEEE] [pdf]
T. Koolen, J. Smith, G. C. Thomas, S. Bertrand, J. Carff, N. Mertins, D. Stephen et al., “Summary of team IHMC’s virtual robotics challenge entry,” in Proceedings of the IEEE-RAS International Conference on Humanoid Robots, 2013, doi: 10.1109/HUMANOIDS.2013.7029992 [IEEE]
G. C. Thomas, C. Gimenez, E. Chin, A. Carmedelle, and A. M. Hoover, “Controllable, High Force Amplification Using Elastic Cable Capstans,” in ASME 2012 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference Volume 4: 36th Mechanisms and Robotics Conference, Parts A and B., Chicago, IL, 2012, pp.885-889. [ASME] [pdf]
E. Culler, G. C. Thomas, and C. L. Lee, “A Perching Landing Gear for a Quadcopter,” in 53rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference, Structures, Structural Dynamics, and Materials and Co-located Conferences., Honolulu, HI, 2012, doi: 10.2514/6.2012-1722 [AIAA]