Leveraging auditory and visual feedback for attention reorientation is essential for natural gaze shifts in social interaction. However, enabling humanoid robots to perform natural and context-appropriate gaze shifts in unconstrained human--robot interaction (HRI) remains challenging, as it requires the coupling of cognitive attention mechanisms and biomimetic motion generation. In this work, we propose the Robot Gaze-Shift (RGS) framework, which integrates these two components into a unified pipeline. First, RGS employs a vision--language model (VLM)-based gaze reasoning pipeline to infer context-appropriate gaze targets from multimodal interaction cues, ensuring consistency with human gaze-orienting regularities. Second, RGS introduces a conditional Vector Quantized-Variational Autoencoder (VQ-VAE) model for eye--head coordinated gaze-shift motion generation, producing diverse and human-like gaze-shift behaviors. Experiments validate that RGS effectively replicates human-like target selection and generates realistic, diverse gaze-shift motions.
Figures & tables
Fig. 1: Overview of our RGS framework.
Fig. 2: VLM-Based Gaze Reasoning Pipeline. Notation: superscripts f , m and ∗ denote the final frame of a cycle, instance masking, and mark indexing, respectively.
Fig. 3: Overview of the proposed gaze-shift motion generation model, trained in two stages. Top: a conditional VQ-VAE is trained to reconstruct eye–head rotation increments from ground-truth motions and conditioning inputs. Bottom: a conditional prior predicts a distribution over codebook entries from the conditioning inputs. The prior selects the maximum-probability code to compute the loss during training, while using stochastic sampling at inference time to enable behavioral diversity.
Fig. 4: Qualitative examples of the proposed VLM-based gaze reasoning pipeline across four gaze-orienting regularities (H1–H4). Each row corresponds to one regularity and shows three representative inference cycles (T1–T3) selected at different times. The three cycles are temporally ordered but not necessarily consecutive. The red semi-transparent overlay indicates the gaze target selected by the pipeline at each illustrated inference cycle.
Regularity
Clips
Correct
Success rate (%)
(H1) Deictic orienting of attention
20
17
85.0
(H2) Social orienting reflex
19
19
100.0
(H3) Turn-taking
20
17
85.0
(H4) Responsive joint attention
17
12
70.6
TABLE I: Human-likeness evaluation of gaze-target selection across four gaze-orienting regularities.
Fig. 5: Validation-set MGD curves for the two-stage training. (a) Training Stage-1: conditional VQ-VAE reconstruction errors. (b) Training Stage-2: conditional prior inference errors. Both stages exhibit consistent error reduction and stable convergence.
Fig. 6: Qualitative visualization of inference-time diversity in eye–head coordinated gaze-shift motion generation. Given identical initial conditions c={θe,θh,xg,3d} , the model generates multiple distinct yet plausible eye–head coordination modes via stochastic code sampling. Red numbers denote sampled discrete code indices, and P indicates the corresponding prior probability (we show samples with probability >5% ).
Gaze coordinates attention in human interaction through coupled eye, head, and eyelid motion. A humanoid robot must choose where to look while generating a suitable movement toward that target; fixed tracking rules alone do not model the temporal structure of human gaze. We separate these tasks with an asynchronous vision-language model that selects a scene referent, a reactive perception module that maintains fixation, and a Realistic Gaze Transformer (RGT) that generates target-conditioned motion. RGT is a Transformer-VAE trained on markerless human recordings retargeted to the robot's 11-DoF joint space: self-supervised pretraining encodes recent full-head history, and autoregressive fine-tuning exposes the model to its own predictions during rollout. At inference, a four-dimensional binocular-eye trajectory conditions coordinated neck and eye motion; an auxiliary blink predictor triggers eyelid templates during playback. On a two-second benchmark in which all controllers receive the same ground-truth target, RGT-Base obtains the lowest reported overall seven-joint MSE, and physical demonstrations show the integrated targeting and control pipeline. The evidence establishes robot-space kinematic fidelity and real-time RGT inference; perceived naturalness and open-vocabulary target-selection accuracy remain questions for controlled evaluation.
Yuhang Hu, Junlin Lyu, Yuan Fang +6
Creative Machines Lab, Department of Mechanical Engineering, Columbia University
Vision-Language-Action (VLA) models have recently shown strong potential for robot learning by following language instructions. However, in practice, language alone is often insufficient to precisely convey human intent. It is difficult to describe which exact object to interact with among similar candidates, where to act on the object, or how the target may change during execution. To address this limitation, we propose Gaze2Act, a novel VLA framework that leverages human gaze as a dynamic and intuitive intent signal for complex interactive manipulation. Gaze2Act first bridges the ego-exo view gap by mapping first-person gaze into the robot's perspective through cross-view semantic matching, producing both an object mask and a gaze point for coarse-to-fine target specification. These cues are then integrated into the policy through perception-level prompting and action-level conditioning, allowing the robot to attend to relevant regions and execute precise interactions under dynamic intent. In a systematic evaluation across seven task categories and 16 real-robot tasks on a Unitree G1 humanoid, Gaze2Act achieves state-of-the-art performance in both intent accuracy and task success rate. It notably outperforms baselines in object disambiguation, fine-grained interaction, and dynamic intent steering. These results demonstrate that human gaze provides a natural, low-burden, and highly expressive modality for human-in-the-loop VLA control.
Goal-directed eye movements are a fundamental component of visuomotor control, enabling humans to anticipate and guide their actions. Whether this anticipatory and task-driven behavior is preserved when actions are executed through a robot rather than through one's own body remains unclear. Here we address this question by investigating gaze behavior during goal-directed telemanipulation to determine how visuomotor control adapts to altered embodiment. Our findings show that gaze remains strongly aligned with task goals, preserving its predictive role even during robot-mediated manipulation. At the same time, teleoperation systematically redistributes visual attention toward the robotic end-effector and manipulated objects, increasing online monitoring. These findings show that predictive gaze is not lost under altered embodiment, but reorganized in response to changes in sensory feedback and control demands. More broadly, they reveal the flexibility of the human visuomotor system when the natural sensorimotor coupling is disrupted and identify gaze as an informative signal for inferring action intentions in human-robot interaction.
Manuela Uliano, Silvia Fattorini, Marco Controzzi
The BioRobotics Institute, Scuola Superiore Sant’Anna; Pisa, Italy · Department of Excellence in Robotics and AI, Scuola Superiore Sant’Anna; Pisa, Italy