EDBT 2026 Demo / reviewers in the wild / expert
Ziang Liu 0002
dblp:244/7499-2
· DBLP profile ↗
8ranked-venue papers
1as first author
7since 2021 · last 2025
0000-0001-6274-0459ORCID · conflict
Domains — the database's venue-derived domains; a paper can count in several
Artificial intelligence and machine learning · 8 · 1 first-author · 7 since 2021Systems, architecture and hardware · 5 · 4 since 2021Human-computer interaction and ubiquitous computing · 2 · 1 first-author · 2 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2025 | GRACE: Generalizing Robot-Assisted Caregiving with User Functionality EmbeddingsabstractRobot caregiving should be personalized to meet the diverse needs of care recipients-assisting with tasks as needed, while taking user agency in action into account. In physical tasks such as handover, bathing, dressing, and rehabilitation, a key aspect of this diversity is the functional range of motion (fROM), which can vary significantly between individuals. In this work, we learn to predict personalized fROM as a way to generalize robot decision-making in a wide range of caregiving tasks. We propose a novel data-driven method for predicting personalized fROM using functional assessment scores from occupational therapy. We develop a neural model that learns to embed functional assessment scores into a latent representation of the user's physical function. The model is trained using motion capture data collected from users with emulated mobility limitations. After training, the model predicts personalized fROM for new users without motion capture. Through simulated experiments and a real-robot user study, we show that the personalized fROM predictions from our model enable the robot to provide personalized and effective assistance while improving the user's agency in action. See our website for more visualizations: https://emprise.cs.cornell.edu/grace/. Ziang Liu 0002, Yuanchen Ju, Yu Da, Tom Silver, Pranav N. Thakkar, Jenna Li, Justin Guo, Katherine Dimitropoulou, Tapomayukh Bhattacharjee |
HRI | 1 |
| 2025 | OpenRoboCare: A Multimodal Multi-Task Expert Demonstration Dataset for Robot CaregivingabstractWe present OpenRoboCare, a multimodal dataset for robot caregiving, capturing expert occupational therapist demonstrations of Activities of Daily Living (ADLs). Caregiving tasks involve complex physical human-robot interactions, requiring precise perception under occlusions, safe physical contact, and long-horizon planning. While recent advances in robot learning from demonstrations have shown promise, there is a lack of a large-scale, diverse, and expert-driven dataset that captures real-world caregiving routines. To address this gap, we collect data from 21 occupational therapists performing 15 ADL tasks on two manikins. The dataset spans five modalities—RGB-D video, pose tracking, eye-gaze tracking, task and action annotations, and tactile sensing, providing rich multimodal insights into caregiver movement, attention, force application, and task execution strategies. We further analyze expert caregiving principles and strategies, offering insights to improve robot efficiency and task feasibility. Additionally, our evaluations demonstrate that OpenRoboCare presents challenges for state-of-the-art robot perception and human activity recognition methods, both critical for developing safe and adaptive assistive robots, highlighting the value of our contribution. See our website for additional visualizations: https://emprise.cs.cornell.edu/robo-care/. Ziang Liu 0002, Kelvin Lin, Edward Gu, Ruolin Ye, Cynthia Hsu, Zhanxin Wu, Xiaoman Yang, Christy Sum Yu Cheung, Harold Soh, Katherine Dimitropoulou, Tapomayukh Bhattacharjee |
IROS | 2 |
| 2024 | Feel the Bite: Robot-Assisted Inside-Mouth Bite Transfer using Robust Mouth Perception and Physical Interaction-Aware ControlabstractRobot-assisted feeding can greatly enhance the lives of those with mobility limitations. Modern feeding systems can pick up and position food in front of a care recipient's mouth for a bite. However, many with severe mobility constraints cannot lean forward and need direct inside-mouth food placement. This demands precision, especially for those with restricted mouth openings, and appropriately reacting to various physical interactions - incidental contacts as the utensil moves inside, impulsive contacts due to sudden muscle spasms, deliberate tongue maneuvers by the person being fed to guide the utensil, and intentional bites. In this paper, we propose an inside-mouth bite transfer system that addresses these challenges with two key components: a multi-view mouth perception pipeline robust to tool occlusion, and a control mechanism that employs multimodal time-series classification to discern and react to different physical interactions. We demonstrate the efficacy of these individual components through two ablation studies. In a full system evaluation, our system successfully fed 13 care recipients with diverse mobility challenges. Participants consistently emphasized the comfort and safety of our inside-mouth bite transfer system, and gave it high technology acceptance ratings - underscoring its transformative potential in real-world scenarios. Supplementary materials and videos can be found at: \hrefhttp://emprise.cs.cornell.edu/bitetransfer/ emprise.cs.cornell.edu/bitetransfer . Rajat Kumar Jenamani, Daniel Stabile, Ziang Liu 0002, Abrar Anwar, Katherine Dimitropoulou, Tapomayukh Bhattacharjee |
HRI | 3 |
| 2024 | REPeat: A Real2Sim2Real Approach for Pre-acquisition of Soft Food Items in Robot-assisted FeedingabstractThe paper presents REPeat, a Real2Sim2Real framework designed to enhance bite acquisition in robot-assisted feeding for soft foods. It uses ‘pre-acquisition actions’ such as pushing, cutting, and flipping to improve the success rate of bite acquisition actions such as skewering, scooping, and twirling. If the data-driven model predicts low success for direct bite acquisition, the system initiates a Real2Sim phase, reconstructing the food’s geometry in a simulation. The robot explores various pre-acquisition actions in the simulation, then a Sim2Real step renders a photorealistic image to reassess success rates. If the success improves, the robot applies the action in reality. We evaluate the system on 15 diverse plates with 10 types of food items for a soft food diet, showing improvement in bite acquisition success rates by 27% on average across all plates. See our project website at emprise.cs.cornell.edu/repeat. Nayoung Ha, Ruolin Ye, Ziang Liu 0002, Shubhangi Sinha, Tapomayukh Bhattacharjee |
IROS | 3 |
| 2022 | Inferring Articulated Rigid Body Dynamics from RGBD VideoabstractBeing able to reproduce physical phenomena ranging from light interaction to contact mechanics, simulators are becoming increasingly useful in more and more application domains where real-world interaction or labeled data are difficult to obtain. Despite recent progress, significant human effort is needed to configure simulators to accurately reproduce real-world behavior. We introduce a pipeline that combines inverse rendering with differentiable simulation to create digital twins of real-world articulated mechanisms from depth or RGB videos. Our approach automatically discovers joint types and estimates their kinematic parameters, while the dynamic properties of the overall mechanism are tuned to attain physically accurate simulations. Control policies optimized in our derived simulation transfer successfully back to the original system, as we demonstrate on a simulated system. Further, our approach accurately reconstructs the kinematic tree of an articulated mechanism being manipulated by a robot, and highly nonlinear dynamics of a real-world coupled pendulum mechanism. Website: https://eric-heiden.github.io/video2sim Eric Heiden, Ziang Liu 0002, Vibhav Vineet, Erwin Coumans, Gaurav S. Sukhatme |
IROS | 2 |
| 2021 | Robotic Lime Picking by Considering Leaves as Permeable ObstaclesabstractThe problem of robotic lime picking is challenging; lime plants have dense foliage which makes it difficult for a robotic arm to grasp a lime without coming in contact with leaves. Existing approaches either do not consider leaves, or treat them as obstacles and completely avoid them, often resulting in undesirable or infeasible plans. We focus on reaching a lime in the presence of dense foliage by considering the leaves of a plant as permeable obstacles with a collision cost. We then adapt the rapidly exploring random tree star (RRT*) algorithm for the problem of fruit harvesting by incorporating the cost of collision with leaves into the path cost. To reduce the time required for finding low-cost paths to goal, we bias the growth of the tree using an artificial potential field (APF). We compare our proposed method with prior work in a 2-D environment and a 6-DOF robot simulation. Our experiments and a real-world demonstration on a robotic lime picking task demonstrate the applicability of our approach. Heramb Nemlekar, Ziang Liu 0002, Suraj Kothawade, Sherdil Niyaz, Barath Raghavan, Stefanos Nikolaidis |
IROS | 2 |
| 2021 | A Hierarchical Approach to Multi-Agent Path FindingabstractSolving Multi-Agent Path Finding (MAPF) instances optimally is NP-hard, and existing optimal and bounded suboptimal MAPF solvers thus usually do not scale to large MAPF instances. Greedy MAPF solvers scale to large MAPF instances, but their solution qualities are often bad. In this paper, we therefore propose a novel MAPF solver, Hierarchical Multi-Agent Path Planner (HMAPP), which creates a spatial hierarchy by partitioning the environment into multiple regions and decomposes a MAPF instance into smaller MAPF sub-instances for each region. For each sub-instance, it uses a bounded-suboptimal MAPF solver to solve it with good solution quality. Our experimental results show that HMAPP is able to solve as large MAPF instances as greedy MAPF solvers while achieving better solution qualities on various maps. Han Zhang 0018, Mingze Yao, Ziang Liu 0002, Jiaoyang Li 0001, Lucas Terr, Shao-Hung Chan, T. K. Satish Kumar, Sven Koenig |
SOCS | 3 |
| 2020 | Physics-based Simulation of Continuous-Wave LIDAR for Localization, Calibration and TrackingabstractLight Detection and Ranging (LIDAR) sensors play an important role in the perception stack of autonomous robots, supplying mapping and localization pipelines with depth measurements of the environment. While their accuracy outperforms other types of depth sensors, such as stereo or time-of-flight cameras, the accurate modeling of LIDAR sensors requires laborious manual calibration that typically does not take into account the interaction of laser light with different surface types, incidence angles and other phenomena that significantly influence measurements. In this work, we introduce a physically plausible model of a 2D continuous-wave LIDAR that accounts for the surface-light interactions and simulates the measurement process in the Hokuyo URG-04LX LIDAR. Through automatic differentiation, we employ gradient-based optimization to estimate model parameters from real sensor measurements. Eric Heiden, Ziang Liu 0002, Ragesh K. Ramachandran, Gaurav S. Sukhatme |
ICRA | 2 |