Publications
Self-tuning Bistable Parametric Oscillator: Near-optimal Amplitude Maximization without Model Information
D.J. Braun, A. Sutas and S. Vijayakumar, Self-tuning Bistable Parametric Oscillator: Near-optimal Amplitude Maximization without Model Information, Physical Review E, 95, 012201, 2017. Theory predicts that parametrically excited oscillators, tuned to operate under resonant condition, are capable of large-amplitude oscillation useful in diverse applications, such as signal…
Optimal Control of Variable Stiffness Policies: Dealing with Switching Dynamics and Model Mismatch
A. Radulescu, J. Nakanishi, D.J. Braun and S. Vijayakumar, Optimal Control of Variable Stiffness Policies: Dealing with Switching Dynamics and Model Mismatch, J. P. Laumond, N. Mansard, J.B. Lasserre, Geometric and Numerical Foundations of Movements, Springer Tracts in Advanced Robotics, vol. 117, pp. 393-419, 2017. Controlling complex…
Compliant Actuation for Energy Efficient Impedance Modulation
D. J. Braun, S. Apte, O. Adiyatov, A. Dahiya and N. Hogan, Compliant actuation for energy efficient impedance modulation, IEEE International Conference on Robotics and Automation, pp. 636-641, 2016. Energy efficient compliant actuation is the missing ingredient and key enabler of next-generation autonomous systems, domestic robots,…
Optimal Parametric Feedback Excitation of Nonlinear Oscillators
D.J. Braun, Optimal parametric feedback excitation of nonlinear oscillators, Physical Review Letters, 116, 044102, 2016. An optimal parametric feedback excitation principle is sought, found, and investigated. The principle is shown to provide an adaptive resonance condition that enables unprecedentedly robust movement generation in a large class of…
Robots Driven by Compliant Actuators: Optimal Control under Actuation Constraints
D.J. Braun, F. Petit, F. Huber, S. Haddadin, P. van der Smagt, A. Albu-Schaffer and S. Vijayakumar, Robots Driven by Compliant Actuators: Optimal Control under Actuation Constraints, IEEE Transactions on Robotics, vol. 29, no. 5, pp. 1085-1101, 2013. This paper is recipient of the 2013 King-Sun Fu IEEE Transactions…
Transferring Human Impedance Behavior to Heterogeneous Variable Impedance Actuators
M. Howard, D.J. Braun, and S. Vijayakumar, Transferring human impedance behavior to heterogeneous variable impedance actuators, IEEE Transactions on Robotics, vol. 29, no. 4, pp. 847-862, 2013. This paper presents a comparative study of approaches to control robots with variable impedance actuators (VIAs) in ways that…
Optimal Variable Stiffness Control: Formulation and Application to Explosive Movement Tasks
D. J. Braun, M. Howard and S. Vijayakumar, Optimal Variable Stiffness Control: Formulation and Application to Explosive Movement Tasks, Autonomous Robots, vol. 33, no.3, pp. 237-253, 2012. It is widely recognized that compliant actuation is advantageous to robot control once dynamic tasks are considered. However, the benefit of…
Simulation of Constrained Mechanical Systems – Part I: An Equation of Motion
D.J. Braun and M. Goldfarb, Simulation of Constrained Mechanical Systems – Part I: An Equation of Motion, ASME Journal of Applied Mechanics, vol. 79, issue 4, 041017, 2012. This paper presents an equation of motion for numerical simulation of constrained mechanical systems with holonomic and nonholonomic constraints.…
Simulation of Constrained Mechanical Systems – Part II: Explicit Numerical Integration
D.J. Braun and M. Goldfarb, Simulation of Constrained Mechanical Systems – Part II: Explicit Numerical Integration, ASME Journal of Applied Mechanics, vol. 79, issue 4, 041018, 2012. This paper presents an explicit to integrate differential algebraic equations (DAEs) method for simulations of constrained mechanical systems modeled with…
Actuated Dynamic Walking in a Seven-Link Biped Robot
D.J. Braun, Jason E. Mitchell and M. Goldfarb, Actuated Dynamic Walking in a Seven-Link Biped Robot, IEEE/ASME Transactions on Mechatronics, vol. 17, no.1, pp. 147-156, 2012. The authors have previously described a method for enabling fully actuated biped walking without prescribing joint angle trajectories or imposing kinematic…
Optimal torque and stiffness control in compliantly actuated robots
D.J. Braun, F. Petit, F. Huber, S. Haddadin, P. Smagt, A. Albu-Schaffer, and S. Vijayakumar, Optimal torque and stiffness control in compliantly actuated robots, IEEE/RSJ International Conference on Intelligent Robots and Systems, Algarve, PT, pp. 2801–2808, October 2012. Anthropomorphic robots that aim to approach human performance…
Exploiting variable physical damping in rapid movement tasks
A. Radulescu, M. Howard, D.J. Braun, and S. Vijayakumar, Exploiting variable physical damping in rapid movement tasks, IEEE/ASME International Conference on Advanced Intelligent Mechatronics, Kaohsiung, TWN, pp. 141–148, July 2012. Best Student Paper Award Finalist. Until now, design of variable physical impedance actuators (VIAs) has been…