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A Robust Closed-Loop Biped Locomotion Planner Based on Time Varying Model Predictive Control [article]

Mohammadreza Kasaei, Nuno Lau, Artur Pereira
2019 arXiv   pre-print
The proposed planner is designed based on a Time-Varying Model Predictive Control (TVMPC) scheme to be able to consider some constraints in the states, inputs and outputs of the system and also mixed input-output  ...  A robust locomotion planner is one of the fundamental components for generating stable biped locomotion.  ...  In this paper, we release this constraint and formulate the problem of developing an online optimal closed-loop biped locomotion planner as a time-varying MPC.  ... 
arXiv:1909.06873v1 fatcat:alou6ahicrfcdkjl27msvku5xy

Dynamic Locomotion For Passive-Ankle Biped Robots And Humanoids Using Whole-Body Locomotion Control [article]

D. Kim, S. Jorgensen, J. Lee, J. Ahn, J. Luo, L. Sentis
2019 arXiv   pre-print
Overall, the main contributions of this work are on: a) achieving various modalities of unsupported dynamic locomotion of passive-ankle bipeds using a WBLC controller and a TVR planner, b) conducting an  ...  To achieve robust dynamic locomotion, we conduct an in-depth analysis of uncertainty for our dynamic walking algorithm called time-to-velocity-reversal (TVR) planner.  ...  This work was supported by the Office of Naval Research, ONR grant #N000141512507, NSF grant #1724360, and a NASA Space Technology Research Fellowship (NSTRF) grant #NNX15AQ42H.  ... 
arXiv:1901.08100v1 fatcat:4uyey5imejewtnzzipqqnnvpei

A Hierarchical Framework to Generate Robust Biped Locomotion Based on Divergent Component of Motion [article]

Mohammadreza Kasaei, Nuno Lau, Artur Pereira
2019 arXiv   pre-print
The control core of the proposed framework is composed of a Linear-Quadratic-Gaussian (LQG) controller and two proportional controllers.  ...  In this framework, the LQG controller tries to track the reference trajectories and the proportional controllers are designed to adjust the next step timing and location that allow the robot to recover  ...  [17] introduced a closed-loop foot placement controller based on CP, which is capable of generating the desired ZMP according to the current CP error.  ... 
arXiv:1911.07505v1 fatcat:45hjjoe7azgwph2nqbyzyvtleq

Highly Dynamic Quadruped Locomotion via Whole-Body Impulse Control and Model Predictive Control [article]

Donghyun Kim, Jared Di Carlo, Benjamin Katz, Gerardo Bledt, and Sangbae Kim
2019 arXiv   pre-print
In this paper, we propose a controller combining whole-body control (WBC) and model predictive control (MPC).  ...  In our framework, MPC finds an optimal reaction force profile over a longer time horizon with a simple model, and WBC computes joint torque, position, and velocity commands based on the reaction forces  ...  Based on this assumption, we create a time-varying linearization of the dynamics using commanded ψ in a rotational matrix, R z (ψ), and set the moment arm in Eq. (2) with the predetermined one from the  ... 
arXiv:1909.06586v1 fatcat:l7u73bp7gfbnbfynjot3ddkn6i

A Planning and Control Framework for Humanoid Systems: Robust, Optimal, and Real-time Performance [article]

Ye Zhao
2017 arXiv   pre-print
A particular concentration is on the robust, optimal and real-time performance.  ...  Second, we take a step toward formally synthesizing high-level reactive planners for whole-body locomotion in constrained environments.  ...  Another close work on agile locomotion is (Mordatch et al., 2010) which proposes a physics-based locomotion controller and devises an online motion planner to generate various types of robust gaits over  ... 
arXiv:1701.05929v1 fatcat:tqsr6sss3jeudcklibi2x6tjmy

Beyond the limits of kinematics in planning keyframed biped locomotion

Tamás Juhász, Tamás Urbancsek
2009 Periodica Polytechnica Electrical Engineering  
Let's assume that a desired reference movement has been designed, it can be simulated using a real-time kinematics model.  ...  Finally, we show our experimental results within a modern simulation environment as well as on our test humanoid platform.  ...  The target angle position control loop is implemented with a simple P controller (the closed loop contains an integrator element, because of the DC motor model).  ... 
doi:10.3311/ fatcat:rf6q2fhfbzcmvje5x2qg37svtu

Control Systems for Human Running using an Inverted Pendulum Model and a Reference Motion Capture Sequence [article]

Taesoo Kwon, Jessica Hodgins
2010 Proceedings of the 2004 ACM SIGGRAPH/Eurographics symposium on Computer animation - SCA '04  
At run-time, the controller plans a desired motion at every frame based on the current estimate of the pendulum state and a predicted pendulum trajectory.  ...  In this paper, we present a balancing control algorithm based on a simplified dynamic model, an inverted pendulum on a cart.  ...  Acknowledgements We thank Junggon Kim for providing his dynamics simulator, Moshe Mahler for modeling the character and video editing, and Justin Macey for motion capture sessions.  ... 
doi:10.2312/sca/sca10/129-138 fatcat:4ot67jaghrbpplvhh67x7piu2y

Modeling and Control of a Hybrid Wheeled Jumping Robot [article]

Traiko Dinev, Songyan Xin, Wolfgang Merkt, Vladimir Ivan, Sethu Vijayakumar
2020 arXiv   pre-print
We provide an analytical derivation of the system dynamics which we use inside a model predictive controller (MPC).  ...  We evaluate the controller on a variety of tasks and uneven terrains in a simulator.  ...  the combined action of wheels and base. • We validate the controller in a closed loop in a physics simulator, and we evaluate the robustness of the MPC with sensor noise and on a rough terrain locomotion  ... 
arXiv:2003.01440v2 fatcat:5btnzi4t35exzgq6lir7scygkq

Toward Safety-Aware Informative Motion Planning for Legged Robots [article]

Sangli Teng, Yukai Gong, Jessy W. Grizzle, Maani Ghaffari
2021 arXiv   pre-print
The planner is based on the Incrementally-exploring Information Gathering (IIG) algorithm and allows closed-loop kinodynamic node expansion using a Model Predictive Control (MPC) formalism.  ...  map of the environment, 2) a robot's dynamics and safety constraints via discrete-time CBFs and MPC for closed-loop multi-horizon node expansions, and 3) an automatic stopping criterion via setting an  ...  Model Predictive Control MPC is designed to resolve a constrained optimal control problem over a finite time horizon. Zeng et al.  ... 
arXiv:2103.14252v1 fatcat:7z5lbckh4bhbpnbsbwoqrsd3vm

Model Predictive Control with Environment Adaptation for Legged Locomotion [article]

Niraj Rathod, Angelo Bratta, Michele Focchi, Mario Zanon, Octavio Villarreal, Claudio Semini, Alberto Bemporad
2021 arXiv   pre-print
In this work, we propose and test in experiments a real-time Nonlinear Model Predictive Control (NMPC) tailored to a legged robot for achieving dynamic locomotion on a variety of terrains.  ...  Our NMPC is based on the real-time iteration scheme that allows us to re-plan online at 25 Hz with a prediction horizon of 2 seconds.  ...  In this work, we propose and test in experiments a real-time Nonlinear Model Predictive Control (NMPC) tailored to a legged robot for achieving dynamic locomotion on a variety of terrains.  ... 
arXiv:2105.05998v3 fatcat:wiahl2oe6nee5mgrvrfqemjzqm

Fast Trajectory Optimization for Legged Robots using Vertex-based ZMP Constraints [article]

Alexander W Winkler, Farbod Farshidian, Diego Pardo, Michael Neunert, Jonas Buchli
2017 arXiv   pre-print
We demonstrate the feasibility of the generated motions on a real quadruped robot.  ...  We introduce a vertex-based representation of the support-area constraint, which can treat arbitrarily oriented point-, line-, and area-contacts uniformly.  ...  Additionally, we plan to utilize the speed of the optimization for Model Predictive Control (MPC). APPENDIX A.  ... 
arXiv:1705.10313v1 fatcat:kiux2w5c2ffuldzw4ao2giptne

Learning Dynamic Bipedal Walking Across Stepping Stones [article]

Helei Duan, Ashish Malik, Mohitvishnu S. Gadde, Jeremy Dao, Alan Fern, Jonathan Hurst
2022 arXiv   pre-print
The resulting controller and model are then integrated with a real-time overhead camera system for detecting stepping stone locations.  ...  We then learn a model of that controller's capabilities, which enables prediction of feasible footsteps given the robot's current dynamic state.  ...  However, there is currently no RL-based approach that has demonstrated closed-loop control of bipedal dynamic walking over stepping stones.  ... 
arXiv:2205.01807v1 fatcat:qztu4vv3qfhsbkym5bixcyanna

Fast Trajectory Optimization for Legged Robots Using Vertex-Based ZMP Constraints

Alexander W. Winkler, Farbod Farshidian, Diego Pardo, Michael Neunert, Jonas Buchli
2017 IEEE Robotics and Automation Letters  
Additionally, we plan to utilize the speed of the optimization for Model Predictive Control (MPC). APPENDIX A.  ...  In order to cope with uncertainties it is essential to incorporate feedback into the control loop.  ... 
doi:10.1109/lra.2017.2723931 dblp:journals/ral/WinklerFPNB17 fatcat:7lluqehqyfhhzlexkrwlkpwhfm

ADHERENT: Learning Human-like Trajectory Generators for Whole-body Control of Humanoid Robots

Paolo Maria Viceconte, Raffaello Camoriano, Giulio Romualdi, Diego Ferigo, Stefano Dafarra, Silvio Traversaro, Giuseppe Oriolo, Lorenzo Rosasco, Daniele Pucci
2022 IEEE Robotics and Automation Letters  
Leveraging human motion capture locomotion data, ADHERENT yields a general footstep planner, including forward, sideways, and backward walking trajectories that blend smoothly from one to another.  ...  Recently, research in computer graphics investigated machinelearning methods for character animation based on training human-like models directly on motion capture data.  ...  For instance, the unicycle planner [3] employs a unicycle model to produce footstep plans at the trajectory optimization layer, constraining the plan to simple directed walking on a plane [4] , [5]  ... 
doi:10.1109/lra.2022.3141658 fatcat:275cp35vtbeezau3iwa3nwtoey

Real-time predictive kinematic evaluation and optimization for biped robots

Arne-Christoph Hildebrandt, Manuel Demmeler, Robert Wittmann, Daniel Wahrmann, Felix Sygulla, Daniel Rixen, Thomas Buschmann
2016 2016 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)  
The method is suitable for real-time control, since the optimization can be stopped if it exceeds a predetermined time budget. In that case, an executable but suboptimal result is used.  ...  Additionally, the parameter set is optimized according to a chosen cost function using a gradient method and the step time is adapted according to a desired mean velocity.  ...  An A*based step-planner calculates a sequence of footsteps based on high-level user input [19] .  ... 
doi:10.1109/iros.2016.7759852 dblp:conf/iros/HildebrandtDWWS16 fatcat:rmmzjx3rcja2vnmtchhiziw4qi
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