Bio


C. Karen Liu is an associate professor in the Computer Science Department at Stanford University. Prior to joining Stanford, Liu was a faculty member at the School of Interactive Computing at Georgia Tech. She received her Ph.D. degree in Computer Science from the University of Washington. Liu's research interests are in computer graphics and robotics, including physics-based animation, character animation, optimal control, reinforcement learning, and computational biomechanics. She developed computational approaches to modeling realistic and natural human movements, learning complex control policies for humanoids and assistive robots, and advancing fundamental numerical simulation and optimal control algorithms. The algorithms and software developed in her lab have fostered interdisciplinary collaboration with researchers in robotics, computer graphics, mechanical engineering, biomechanics, neuroscience, and biology. Liu received a National Science Foundation CAREER Award, an Alfred P. Sloan Fellowship, and was named Young Innovators Under 35 by Technology Review. In 2012, Liu received the ACM SIGGRAPH Significant New Researcher Award for her contribution in the field of computer graphics.

Honors & Awards


  • ACM SIGGRAPH Academy, ACM (2021)
  • SIGGRAPH Significant New Research Award, ACM (2012)
  • Alfred P. Sloan Research Fellowship, Alfred P. Sloan Foundation (2010)
  • Young Innovators Under 35, MIT Technology Review (2007)
  • CAREER Award, National Science Foundation (2007)

Professional Education


  • BS, National Taiwan University, Computer Science (1999)
  • MS, University of Washington, Computer Science (2001)
  • PhD, University of Washington, Computer Science (2005)

Stanford Advisees


All Publications


  • Characterizing Multidimensional Capacitive Servoing for Physical Human-Robot Interaction IEEE TRANSACTIONS ON ROBOTICS Erickson, Z., Clever, H. M., Gangaram, V., Xing, E., Turk, G., Liu, C., Kemp, C. C. 2022
  • A Survey on Reinforcement Learning Methods in Character Animation Kwiatkowski, A., Alvarado, E., Kalogeiton, V., Liu, C., Pettre, J., van de Panne, M., Cani, M. WILEY. 2022: 613-639

    View details for DOI 10.1111/cgf.14504

    View details for Web of Science ID 000802723900045

  • Learning to Navigate Sidewalks in Outdoor Environments IEEE ROBOTICS AND AUTOMATION LETTERS Sorokin, M., Tan, J., Liu, C., Ha, S. 2022; 7 (2): 3906-3913
  • DCL: Differential Contrastive Learning for Geometry-Aware Depth Synthesis IEEE ROBOTICS AND AUTOMATION LETTERS Shen, Y., Yang, Y., Zheng, Y., Liu, C., Guibas, L. J. 2022; 7 (2): 4845-4852
  • GIMO: Gaze-Informed Human Motion Prediction in Context Zheng, Y., Yang, Y., Mo, K., Li, J., Yu, T., Liu, Y., Liu, C., Guibas, L. J., Avidan, S., Brostow, G., Cisse, M., Farinella, G. M., Hassner, T. SPRINGER INTERNATIONAL PUBLISHING AG. 2022: 676-694
  • ADeLA: Automatic Dense Labeling with Attention for Viewpoint Adaptation in Semantic Segmentation Conference on Computer Vision and Pattern Recognition (CVPR) Yang, Y., Ren, H., Wang, H., Shen, B., Fan, Q., Zheng, Y., Liu, C., Guibas, L. 2022
  • Data-Augmented Contact Model for Rigid Body Simulation Learning for Dynamics & Control Conference (L4DC) Jian, Y., Sun, J., Liu, C. 2022
  • Learning Diverse and Physically Feasible Dexterous Grasps with Generative Model and Bilevel Optimization Conference on Robot Learning (CoRL) Wu, A., Guo, M., Liu, C. 2022
  • Transformer Inertial Poser: Real-time Human Motion Reconstruction from Sparse IMUs with Simultaneous Terrain Generation Proceedings of SIGGRAPH Asia Jiang, Y., Ye, Y., Gopinath, D., Won, J., Winkler, A., Liu, C. 2022
  • BEHAVIOR-1K: A Benchmark for Embodied AI with 1,000 Everyday Activities and Realistic Simulation Conference on Robot Learning (CoRL) Li, C. 2022
  • Real-time Model Predictive Control and System Identification Using Differentiable Physics Simulation IEEE Robotics and Automation Letters, Chen, S., Werling, K., Wu, A., Liu, C. 2022
  • Scene Synthesis from Human Motion Proceedings of ACM SIGGRAPH Asia Ye, S., Wang, Y., Li, J., Park, D., Liu, C., Xu, H., Wu, J. 2022
  • Task-Specific Design Optimization and Fabrication for Inflated-Beam Soft Robots with Growable Discrete Joints IEEE International Conference on Robotics and Automation (ICRA) Exachos, I., Wang, K., Do, B., Stroppa, F., Coad, M., Okamura, A., Liu, C. 2022
  • Learning Human Search Behavior from Egocentric Visual Inputs COMPUTER GRAPHICS FORUM Sorokin, M., Yu, W., Ha, S., Liu, C. 2021; 40 (2): 389-398

    View details for DOI 10.1111/cgf.142641

    View details for Web of Science ID 000657959600032

  • The Role of Physics-Based Simulators in Robotics ANNUAL REVIEW OF CONTROL, ROBOTICS, AND AUTONOMOUS SYSTEMS, VOL 4, 2021 Liu, C., Negrut, D., Leonard, N. E. 2021; 4: 35-58
  • Protective Policy Transfer Yu, W., Turk, G., Liu, C. K. 2021
  • SimGAN: Hybrid Simulator Identification for Domain Adaptation via Adversarial Reinforcement Learning Jiang, Y., Zhang, T., Ho, D., Bai, Y., Liu, C. K., Levine, S., Tan, J. 2021
  • Policy Transfer via Kinematic Domain Randomization and Adaptation Exarchos, I., Jiang, Y., Yu, W., Liu, C. K. 2021
  • Fast and Feature-Complete Differentiable Physics for Articulated Rigid Bodies with Contact Werling, K., Omens, D., Lee, J., Exarchos, I., Liu, C. K. 2021
  • Error-Aware Policy Learning: Zero-Shot Generalization in Partially Observable Dynamic Environments Kumar, V. C., Ha, S., Liu, C. K. 2021
  • Learning Task-Agnostic Action Spaces for Movement Optimization IEEE Transactions on Computer Graphics and Visualization Babadi, A., van de Panne, M., Liu, C. K., Hämäläinen, P. 2021
  • COCOI: Contact-aware Online Context Inference for Generalizable Non-planar Pushing Xu, Z., Yu, W., Herzog, A., Lu, W., Fu, C., Tomizuka, M., Bai, Y., Liu, C. K., Ho, D. 2021
  • iGibson 2.0: Object-Centric Simulation for Robot Learning of Everyday Household Tasks Li, C., Xia, F., Martin-Martin, R., Lingelbach, M., Srivastava, S., Shen, B., Vainio, K., Gokmen, C., Dharan, G., Jain, T., Kurenkov, A., Liu, C. K., Gweon, H., Wu, J., Fei-Fei, L., Savarese, S. 2021
  • Co-GAIL Learning Diverse Strategies for Human-Robot Collaboration Wang, C., Pérez-D'Arpino, C., Xu, D., Fei-Fei, L., Liu, C. K., Savarese, S. 2021
  • BEHAVIOR: Benchmark for Everyday Household Activities in Virtual, Interactive, and Ecological Environments Srivastava, S., Li, C., Lingelbach, M., Martin-Martin, R., Xia, F., Vainio, K., Lian, Z., Gokmen, C., Buch, S., Liu, C. K., Savarese, S., Gweon, H., Wu, J., Fei-Fei, L. 2021
  • DASH: Modularized Human Manipulation Simulation with Vision and Language for Embodied AI Jiang, Y., Guo, M., Li, J., Exarchos, I., Wu, J., Liu, C. K. 2021
  • Learning to Manipulate Amorphous Materials ACM TRANSACTIONS ON GRAPHICS Zhang, Y., Yu, W., Liu, C., Kemp, C., Turk, G. 2020; 39 (6)
  • Learning to Collaborate From Simulation for Robot-Assisted Dressing IEEE ROBOTICS AND AUTOMATION LETTERS Clegg, A., Erickson, Z., Grady, P., Turk, G., Kemp, C. C., Liu, C. 2020; 5 (2): 2746–53
  • Learning a Control Policy for Fall Prevention on an Assistive Walking Device Kumar, V. C., Ha, S., Sawicki, G., Liu, C. K. 2020
  • Assistive Gym: A Physics Simulation Framework for Assistive Robotics Erickson, Z., Gangaram, V., Kapusta, A., Liu, C. K., Kemp, C. C. 2020
  • Visualizing Movement Control Optimization Landscapes. IEEE transactions on visualization and computer graphics Hamalainen, P. n., Toikka, J. n., Babadi, A. n., Liu, K. n. 2020; PP

    Abstract

    A large body of animation research focuses on optimization of movement control, either as action sequences or policy parameters. However, as closed-form expressions of the objective functions are often not available, our understanding of the optimization problems is limited. Building on recent work on analyzing neural network training, we contribute novel visualizations of high-dimensional control optimization landscapes; this yields insights into why control optimization is hard and why common practices like early termination and spline-based action parameterizations make optimization easier. For example, our experiments show how trajectory optimization can become increasingly ill-conditioned with longer trajectories, but parameterizing control as partial target states-e.g., target angles converted to torques using a PD-controller-can act as an efficient preconditioner. Both our visualizations and quantitative empirical data also indicate that neural network policy optimization scales better than trajectory optimization for long planning horizons. Our work advances the understanding of movement optimization and our visualizations should also provide value in educational use.

    View details for DOI 10.1109/TVCG.2020.3018187

    View details for PubMedID 32816675

  • Bodies at Rest: 3D Human Pose and Shape Estimation from a Pressure Image using Synthetic Data Clever, H. M., Erickson, Z., Kapusta, A., Turk, G., Liu, C., Kemp, C. C., IEEE IEEE. 2020: 6214–23
  • Estimating Mass Distribution of Articulated Objects using Non-prehensile Manipulation Kumar, K. N., Essa, I., Ha, S., Liu, C. K. 2020
  • Learning a Control Policy for Fall Prevention on an Assistive Walking Device Kumar, V., Ha, S., Sawicki, G., Liu, C. K. 2020
  • Personalized collaborative plans for robot-assisted dressing via optimization and simulation AUTONOMOUS ROBOTS Kapusta, A., Erickson, Z., Clever, H. M., Yu, W., Liu, C., Turk, G., Kemp, C. C. 2019; 43 (8): 2183–2207
  • Synthesis of Biologically Realistic Human Motion Using Joint Torque Actuation ACM TRANSACTIONS ON GRAPHICS Jiang, Y., Van Wouwe, T., De Groote, F., Liu, C. 2019; 38 (4)
  • Sim-to-Real Transfer for Biped Locomotion IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) Yu, W., Kumar, V. C., Turk, G., Liu, C. 2019
  • Policy Transfer with Strategy Optimization Yu, W., Liu, C., Turk, G. 2019
  • Multidimensional Capacitive Sensing for Robot-Assisted Dressing and Bathing Erickson, Z., Clever, H. M., Gangaram, V., Turk, G., Liu, C., Kemp, C. C. 2019