Robotics Reinforcement Learning Character Animation Motion Tracking

My friends call me Alex and I work as a Research Scientist at Meta Reality Labs in San Francisco. I study the physical principles of human and animal movement to replicate them with robots or virtual agents. This work lies at the intersection of Reinforcement learning, Character animation, Motion Tracking and Robotics. I did my PhD at the Agile and Dexterous Robotics Lab at ETH Zurich, where I worked on robot motion-planning, trajectory optimization, and model-based control for quadruped robots. I received my Masters in Mechanical Engineering at the Karlsruhe Institute of Technology.

Happy to get in touch! [Twitter, Youtube, Scholar, Github, LinkedIn]



Perpetual Humanoid Control for Real-time Simulated Avatars
Z Luo, J Cao, A Winkler, K Kitani, W Xu
International Conference on Computer Vision (ICCV 2023)
[Project page] [Paper]
Physics-based Motion Retargeting from Sparse Inputs
D Reda, J Won, Y Ye, M van de Panne, A Winkler
ACM Symposium on Computer Animation (SCA 2023)
[Project page] [Paper]
QuestEnvSim: Environment-Aware Simulated Motion Tracking from Sparse Sensors
S Lee, S Starke, Y Ye, J Won, A Winkler
[Project page] [Paper]
QuestSim: Human Motion Tracking from sparse Sensors with Simulated Avatars
A Winkler, J Won, Y Ye
[Project page] [Paper]
Transformer Inertial Poser: Real-time Human Motion Reconstruction from Sparse IMUs with Simultaneous Terrain Generation
Y Jiang, Y Ye, D Gopinath, J Won, A Winkler, K Liu
[Project page] [Paper]
Gato: Gait and Trajectory Optimization for legged systems through Phase-based Endeffector Parameterization
A Winkler, D Bellicoso, M Hutter, J Buchli
IEEE Robotics and Automation Letter (RA-L 2018)
[Project page] [Paper]
Ph.D. Thesis: Optimization-based motion planning for legged Robots
A Winkler
ETH Zurich 2018
Fast Trajectory Optimization for Legged Robots using Vertex-based ZMP Constraints
A Winkler, F Farshidian, D Pardo, M Neunert, J Buchli
IEEE Robotics and Automation Letter (RA-L 2017)
[Paper] [Video] [Link]
Robust Whole-Body Motion Control of Legged Robots
F Farshidian, E Jelavic, A Winkler, J Buchli
IEEE International Conference on Intelligent Robots and Systems (IROS 2017)
[Paper] [Video] [Link]
Hybrid direct collocation and control in the constraint-consistent subspace for dynamic legged robot locomotion
D Pardo, M Neunert, A Winkler, R Grandia, J Buchli
Robotics, Science and Systems (RSS 2017)
[Paper] [Video] [Link]
Online Walking Motion and Foothold Optimization for Quadruped Locomotion
A Winkler, F Farshidian, M Neunert, D Pardo, J Buchli
IEEE International Conference on Robotics and Automation (ICRA 2017)
[Paper] [Video] [Link]
An Efficient Optimal Planning and Control Framework For Quadrupedal Locomotion
F Farshidian, M Neunert, A Winkler, G Rey, J Buchli
IEEE International Conference on Robotics and Automation (ICRA 2017)
[Paper] [Video] [Link]
Trajectory Optimization Through Contacts and Automatic Gait Discovery for Quadrupeds
M Neunert, F Farshidian, A Winkler, J Buchli
IEEE Robotics and Automation Letters (RA-L 2017)
[Paper] [Video] [Link]
Optimal and Learning Control for Autonomous Robots
J Buchli, F Farshidian, A Winkler, T Sandy, M Giftthaler
arXiv 2017
Evaluating direct transcription and nonlinear optimization methods for robot motion planning
D Pardo, L Moller, M Neunert, A Winkler, J Buchli
IEEE Robotics and Automation Letters (RA-L 2016)
[Paper] [Video] [Link]
Planning and Execution of Dynamic Whole-Body Locomotion for a Hydraulic Quadruped on Challenging Terrain
A Winkler, C Mastalli, I Havoutis, M Focchi, D Caldwell, C Semini
IEEE International Conference on Robotics and Automation (ICRA 2015)
[Paper] [Video] [Link]
On-line and on-board planning for quadrupedal locomotion, using practical, on-board perception
C Mastalli, I Havoutis, A Winkler, D Caldwell, C Semini
IEEE International Conference on Practial Robot Applications 2015
Path planning with force-based foothold adaptation and virtual model control for torque controlled quadruped robots
A Winkler, I Havoutis, S Bazeille, J Ortiz, M Focchi, R Dillmann, D Caldwell, C Semini
IEEE International Conference on Robotics and Automation (ICRA 2014)
[Paper] [Video] [Link]


All code is published on Github.

Light-weight and extensible C++ library for trajectory optimization for legged robots.

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Eigen-based and light-weight C++ Interface for NLP Solvers (Ipopt, Snopt).

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Visualization of legged robots, forces, support areas, ZMP, CoM etc. in ROS rviz.

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