Zhengzhe Zhu

dblp:264/7369 · DBLP profile ↗
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12ranked-venue papers
2as first author
11since 2021 · last 2026
0000-0001-9935-0518ORCID · verified

Domains — the database's venue-derived domains; a paper can count in several

Human-computer interaction and ubiquitous computing · 12 · 2 first-author · 11 since 2021
YearPublicationVenuePosition
2026 AmIWrite: Exploring Scalable One-on-One Handwriting-Based Tutoring for Mathematical Problem-Solving with an LLM-Powered AI Tutor
abstract
Real-time handwriting interactions between tutors and students —where tutors observe individual problem-solving processes, provide personalized annotations, and adapt explanations based on students’ work—are fundamental to effective STEM tutoring. However, scaling such personalized handwriting-based tutoring remains challenging—human tutors cannot be available to every student on demand, and current online platforms often fail to recreate equivalent learning experiences. As an initial step toward tackling this challenge, we present AmIWrite, an LLM-powered AI tutoring system for mathematical problem-solving that provides real-time co-speech handwriting interactions on tablet devices, instantiated here as a case study in linear algebra. We conducted a within-subjects study (N = 40) comparing AmIWrite to a text-based AI tutor on two linear algebra topics. Our case study demonstrates how a multimodal AI tutor can preserve the pedagogical benefits of handwriting-based math tutoring and offer a potential path toward more scalable one-on-one STEM tutoring.
Ziyi Liu 0004, Yuzhao Chen, Runlin Duan, Zhengzhe Zhu, Xiyun Hu, Kylie Peppler, Karthik Ramani
CHI5
2025 GesPrompt: Leveraging Co-Speech Gestures to Augment LLM-Based Interaction in Virtual Reality
abstract
Large Language Model (LLM)-based copilots have shown great potential in Extended Reality (XR) applications.However, the user faces challenges when describing the 3D environments to the copilots due to the complexity of conveying spatial-temporal information through text or speech alone.To address this, we introduce GesPrompt, a multimodal XR interface that combines co-speech gestures with speech, allowing end-users to communicate more naturally and accurately with LLM-based copilots in XR environments.By incorporating gestures, GesPrompt extracts spatial-temporal reference from co-speech gestures, reducing the need for precise textual prompts and minimizing cognitive load for end-users.Our contributions include (1) a workflow to integrate gesture and speech input in the XR environment, (2) a prototype VR system that implements the workflow, and (3) a user study demonstrating its effectiveness in improving user communication in VR environments.
Xiyun Hu, Dizhi Ma, Fengming He, Zhengzhe Zhu, Shao-Kang Hsia, Chenfei Zhu, Ziyi Liu 0004, Karthik Ramani
Conference on Designing Interactive Systems4
2024 ClassMeta: Designing Interactive Virtual Classmate to Promote VR Classroom Participation
abstract
Peer influence plays a crucial role in promoting classroom participation, where behaviors from active students can contribute to a collective classroom learning experience. However, the presence of these active students depends on several conditions and is not consistently available across all circumstances. Recently, Large Language Models (LLMs) such as GPT have demonstrated the ability to simulate diverse human behaviors convincingly due to their capacity to generate contextually coherent responses based on their role settings. Inspired by this advancement in technology, we designed ClassMeta, a GPT-4 powered agent to help promote classroom participation by playing the role of an active student. These agents, which are embodied as 3D avatars in virtual reality, interact with actual instructors and students with both spoken language and body gestures. We conducted a comparative study to investigate the potential of ClassMeta for improving the overall learning experience of the class.
Ziyi Liu 0004, Zhengzhe Zhu, Enze Jiang, Xiyun Hu, Kylie Peppler, Karthik Ramani
CHI2
2024 avaTTAR: Table Tennis Stroke Training with Embodied and Detached Visualization in Augmented Reality
abstract
Table tennis stroke training is a critical aspect of player development. We designed a new augmented reality (AR) system, avaTTAR, for table tennis stroke training. The system provides both “on-body” (first-person view) and “detached” (third-person view) visual cues, enabling users to visualize target strokes and correct their attempts effectively with this dual perspectives setup. By employing a combination of pose estimation algorithms and IMU sensors, avaTTAR captures and reconstructs the 3D body pose and paddle orientation of users during practice, allowing real-time comparison with expert strokes. Through a user study, we affirm avaTTAR ’s capacity to amplify player experience and training results.
Dizhi Ma, Xiyun Hu, Jingyu Shi, Mayank Patel 0005, Rahul Jain 0018, Ziyi Liu 0004, Zhengzhe Zhu, Karthik Ramani
UIST7
2024 AdapTUI: Adaptation of Geometric-Feature-Based Tangible User Interfaces in Augmented Reality
abstract
With the advents in geometry perception and Augmented Reality (AR), end-users can customize Tangible User Interfaces (TUIs) that control digital assets using intuitive and comfortable interactions with physical geometries (e.g., edges and surfaces). However, it remains challenging to adapt such TUIs in varied physical environments while maintaining the same spatial and ergonomic affordance. We propose AdapTUI, an end-to- end system that enables an end-user to author geometric-based TUIs and automatically adapts the TUIs when the user moves to a new environment. Leveraging a geometry detection module and the spatial awareness of AR, AdapTUI first lets users create custom mappings between geometric features and digital functions. Then, AdapTUI uses an optimization-based adaptation framework, which considers both the geometric variations and human-factor nuances, to dynamically adjust the attachment of the user-authored TUIs. We demonstrate three application scenarios where end-users can utilize TUIs at different locations, including portable car play, efficient AR workstation, and entertainment. We evaluated the effectiveness of the adaptation method as well as the overall usability through a comparison user study (N=12). The satisfactory adaptation of the user-authored TUIs and the positive qualitative feedback demonstrate the effectiveness of our system.
Fengming He, Xiyun Hu, Xun Qian, Zhengzhe Zhu, Karthik Ramani
Proc. ACM Hum. Comput. Interact.4
2023 InstruMentAR: Auto-Generation of Augmented Reality Tutorials for Operating Digital Instruments Through Recording Embodied Demonstration
abstract
Augmented Reality tutorials, which provide necessary context by directly superimposing visual guidance on the physical referent, represent an effective way of scaffolding complex instrument operations. However, current AR tutorial authoring processes are not seamless as they require users to continuously alternate between operating instruments and interacting with virtual elements. We present InstruMentAR, a system that automatically generates AR tutorials through recording user demonstrations. We design a multimodal approach that fuses gestural information and hand-worn pressure sensor data to detect and register the user’s step-by-step manipulations on the control panel. With this information, the system autonomously generates virtual cues with designated scales to respective locations for each step. Voice recognition and background capture are employed to automate the creation of text and images as AR content. For novice users receiving the authored AR tutorials, we facilitate immediate feedback through haptic modules. We compared InstruMentAR with traditional systems in the user study.
Ziyi Liu 0004, Zhengzhe Zhu, Enze Jiang, Feichi Huang, Ana M. Villanueva, Xun Qian, Tianyi Wang 0004, Karthik Ramani
CHI2
2023 LearnIoTVR: An End-to-End Virtual Reality Environment Providing Authentic Learning Experiences for Internet of Things
abstract
The rapid growth of Internet-of-Things (IoT) applications has generated interest from many industries and a need for graduates with relevant knowledge. An IoT system is comprised of spatially distributed interactions between humans and various interconnected IoT components. These interactions are contextualized within their ambient environment, thus impeding educators from recreating authentic tasks for hands-on IoT learning. We propose LearnIoTVR, an end-to-end virtual reality (VR) learning environment which helps students to acquire IoT knowledge through immersive design, programming, and exploration of real-world environments empowered by IoT (e.g., a smart house). The students start the learning process by installing virtual IoT components we created in different locations inside the VR environment so that the learning will be situated in the same context where the IoT is applied. With our custom-designed 3D block-based language, students can program IoT behaviors directly within VR and get immediate feedback on their programming outcome. In the user study, we evaluated the learning outcomes among students using LearnIoTVR with a pre- and post-test to understand to what extent does engagement in LearnIoTVR lead to gains in learning programming skills and IoT competencies. Additionally, we examined what aspects of LearnIoTVR support usability and learning of programming skills compared to a traditional desktop-based learning environment. The results from these studies were promising. We also acquired insightful user feedback which provides inspiration for further expansions of this system.
Zhengzhe Zhu, Ziyi Liu 0004, Youyou Zhang, Joey Huang, Ana M. Villanueva, Xun Qian, Kylie Peppler, Karthik Ramani
CHI1
2023 Ubi-TOUCH: Ubiquitous Tangible Object Utilization through Consistent Hand-object interaction in Augmented Reality
abstract
Utilizing everyday objects as tangible proxies for Augmented Reality (AR) provides users with haptic feedback while interacting with virtual objects. Yet, existing methods focus on the attributes of the objects, constraining the possible proxies and yielding inconsistency in user experience. Therefore, we propose Ubi-TOUCH, an AR system that assists users in seeking a wider range of tangible proxies for AR applications based on the hand-object interaction (HOI) they desire. Given the target interaction with a virtual object, the system scans the users’ vicinity and recommends object proxies with similar interactions. Upon user selection, the system simultaneously tracks and maps users’ physical HOI to the virtual HOI, adaptively optimizing object 6 DoF and the hand gesture to provide consistency between the interactions. We showcase promising use cases of Ubi-TOUCH, such as remote tutorials, AR gaming, and Smart Home control. Finally, we evaluate the performance and usability of Ubi-TOUCH with a user study.
Rahul Jain 0018, Jingyu Shi, Runlin Duan, Zhengzhe Zhu, Xun Qian, Karthik Ramani
UIST4
2022 MechARspace: An Authoring System Enabling Bidirectional Binding of Augmented Reality with Toys in Real-time
abstract
Augmented Reality (AR), which blends physical and virtual worlds, presents the possibility of enhancing traditional toy design. By leveraging bidirectional virtual-physical interactions between humans and the designed artifact, such AR-enhanced toys can provide more playful and interactive experiences for traditional toys. However, designers are constrained by the complexity and technical difficulties of the current AR content creation processes. We propose MechARspace, an immersive authoring system that supports users to create toy-AR interactions through direct manipulation and visual programming. Based on the elicitation study, we propose a bidirectional interaction model which maps both ways: from the toy inputs to reactions of AR content, and also from the AR content to the toy reactions. This model guides the design of our system which includes a plug-and-play hardware toolkit and an in-situ authoring interface. We present multiple use cases enabled by MechARspace to validate this interaction model. Finally, we evaluate our system with a two-session user study where users first recreated a set of predefined toy-AR interactions and then implemented their own AR-enhanced toy designs.
Zhengzhe Zhu, Ziyi Liu 0004, Tianyi Wang 0004, Youyou Zhang, Xun Qian, Pashin Farsak Raja, Ana M. Villanueva, Karthik Ramani
UIST1
2022 ColabAR: A Toolkit for Remote Collaboration in Tangible Augmented Reality Laboratories
abstract
Current times are accelerating new technologies to provide high-quality education for remote collaboration, as well as hands-on learning. This is particularly important in the case of laboratory-based classes, which play an essential role in STEM education. In this paper, we introduce ColabAR, a toolkit that uses physical proxies to manipulate virtual objects in Tangible Augmented Reality (TAR) laboratories. ColabAR introduces haptic-based customizable interaction techniques to promote remote collaboration between students. Our toolkit provides hardware and software that enable haptic feedback to improve user experience and promote collaboration during learning. Also, we present the architecture of our cloud platform for haptic interaction that supports information sharing between students in a TAR laboratory. We performed two user studies (N=40) to test the effect of our toolkit in enriching local and remote collaborative experiences. Finally, we demonstrated that our TAR laboratory enables students' performance (i.e., lab completion rate, lab scores) to be similar to their performance in an in-person laboratory.
Ana M. Villanueva, Zhengzhe Zhu, Ziyi Liu 0004, Subramanian Chidambaram, Karthik Ramani
Proc. ACM Hum. Comput. Interact.2
2021 RobotAR: An Augmented Reality Compatible Teleconsulting Robotics Toolkit for Augmented Makerspace Experiences
abstract
Distance learning is facing a critical moment finding a balance between high quality education for remote students and engaging them in hands-on learning. This is particularly relevant for project-based classrooms and makerspaces, which typically require extensive trouble-shooting and example demonstrations from instructors. We present RobotAR, a teleconsulting robotics toolkit for creating Augmented Reality (AR) makerspaces. We present the hardware and software for an AR-compatible robot, which behaves as a student’s voice assistant and can be embodied by the instructor for teleconsultation. As a desktop-based teleconsulting agent, the instructor has control of the robot’s joints and position to better focus on areas of interest inside the workspace. Similarly, the instructor has access to the student’s virtual environment and the capability to create AR content to aid the student with problem-solving. We also performed a user study which compares current techniques for distance hands-on learning and an implementation of our toolkit.
Ana M. Villanueva, Ziyi Liu 0004, Zhengzhe Zhu, Joey Huang, Kylie Peppler, Karthik Ramani
CHI3
2020 Meta-AR-App: An Authoring Platform for Collaborative Augmented Reality in STEM Classrooms
abstract
Augmented Reality (AR) has become a valuable tool for education and training processes. Meanwhile, cloud-based technologies can foster collaboration and other interaction modalities to enhance learning. We combine the cloud capabilities with AR technologies to present Meta-AR-App, an authoring platform for collaborative AR, which enables authoring between instructors and students. Additionally, we introduce a new application of an established collaboration process, the pull-based development model, to enable sharing and retrieving of AR learning content. We customize this model and create two modalities of interaction for the classroom: local (student to student) and global (instructor to class) pull. Based on observations from our user studies, we organize a four-category classroom model which implements our system: Work, Design, Collaboration, and Technology. Further, our system enables an iterative improvement workflow of the class content and enables synergistic collaboration that empowers students to be active agents in the learning process.
Ana M. Villanueva, Zhengzhe Zhu, Ziyi Liu 0004, Kylie Peppler, Thomas Redick, Karthik Ramani
CHI2