Journal Papers
Learning Finite-Horizon Optimal Control with Unknown Control-Affine Dynamics
Y. Chen, Y. Li and D.J. Braun, Learning Finite-Horizon Nonlinear Optimal Control Policies with Unknown Control-Affine Dynamics (under review). This paper introduces a model-free method for learning finite-horizon optimal control for…
Variable Stiffness Floating Spring Leg: Performing net-zero energy cost tasks not achievable using fixed stiffness springs
S.Y. Kim and D.J. Braun, Variable Stiffness Floating Spring Leg: Performing net-zero energy cost tasks not achievable using fixed stiffness springs, vol. 8, no. 9, pp. 5400-5407, 2023. Sitting down and…
Data-Driven Iterative Optimal Control for Switched Dynamical Systems
Y. Chen, Y. Li, and D.J. Braun, Data-Driven Iterative Optimal Control for Switched Dynamical Systems, IEEE Robotics and Automation Letters, vol. 8, no. 1, pp. 296-303, 2023. This article presents…
Design of Parallel Variable Stiffness Actuators
C. Mathews and D.J. Braun, Design of Parallel Variable Stiffness Actuators, IEEE Transactions on Robotics, vol. 39, no. 1, pp. 768-782, 2023. Direct-drive motors (DDMs) have been increasingly used for robot actuation because they…
Theory of Fast Walking With Human-Driven Load-Carrying Robot Exoskeletons
T. Zhang and D.J. Braun, Theory of Fast Walking With Human-Driven Load-Carrying Robot Exoskeletons, Transactions on Neural Systems and Rehabilitation Engineering, vol. 30, pp. 1971-1981, 2022. Reaching and maintaining high…
Iterative Online Optimal Feedback Control
Y. Chen and D.J. Braun, Iterative Online Optimal Feedback Control, vol. 66, no. 2, pp. 566-580, IEEE Transactions on Automatic Control, 2021. This article proposes a data-driven iterative feedback control method to efficiently solve…
How to Run 50% Faster without External Energy
A. Sutrisno and D.J. Braun, How to Run 50% Faster without External Energy, vol. 6, no. 13, eaay1950, Science Advances, 2020. Technological innovations may enable next-generation running shoes to provide unprecedented mobility. But how…
Operational Space Control under Actuation Constraints using Strictly Convex Optimization
D.J. Braun, Y. Chen, L. Li, Operational Space Control under Actuation Constraints using Strictly Convex Optimization, vol. 36, no. 1, pp. 302-309, IEEE Transactions on Robotics, 2019. Operational space feedback controllers can be used…
Hardware-in-the-Loop Iterative Optimal Feedback Control without Model-based Future Prediction
Y. Chen and D. J. Braun, Hardware-in-the-Loop Iterative Optimal Feedback Control without Model-based Future Prediction, vol. 35, no. 6, pp. 1419-1434, IEEE Transactions on Robotics, 2019. Optimal control provides a systematic approach to…
Variable Stiffness Spring Actuators for Low Energy Cost Stiffness Modulation
D.J. Braun, V. Chalvet, Chong T.-H., S.S. Apte and N. Hogan, Variable Stiffness Spring Actuators for Low Energy Cost Stiffness Modulation, vol. 35, no. 6, pp. 1435-1449, IEEE Transactions on Robotics, 2019. Theoretical studies…
Multiphase and Multivariable Linear Controllers that Account for the Joint Torques in Normal Human Walking
E.S. Altinkaynak and D.J. Braun, Multiphase and Multivariable Linear Controllers that Account for the Joint Torques in Normal Human Walking, IEEE Transactions on Biomedical Engineering, 2019. Objective: The objective of this paper…
A Phase-Invariant Linear Torque-Angle-Velocity Relation Hidden in the Human Walking Data
E.S. Altinkaynak and D.J. Braun, A Phase-Invariant Linear Torque-Angle-Velocity Relation Hidden in the Human Walking Data, vol. 27, no. 4, pp. 702-711, IEEE Transactions on Neural Systems & Rehabilitation Engineering, 2019. Human…