Organizations: Amazon Fulfillment Technologies & Robotics, Westborough MA, USA · Institute for Experiential Robotics, Northeastern University, Boston MA, USA · School of Computer, Data & Information Sciences, University of Wisconsin - Madison, Madison WI, USA
Shared autonomy is a control paradigm that combines human cognitive abilities with robot precision to enable effective remote manipulation in complex environments. A key challenge is how to adapt the level of autonomy using information extracted from the human, task, and/or environment. In this paper, we propose a novel arbitration strategy that dynamically adjusts the level of autonomy in the system using the entropy of a belief distribution derived from a multimodal intent inference. Human intent is modeled with a Dynamic Bayesian Network (DBN), which updates beliefs over goals given real-time operator gaze data and robot arm motion during teleoperation. We then formulate the blending of human input and autonomous control as a Model Predictive Control (MPC) problem, where the system's autonomous behavior is guided by the belief distribution. This approach enables continuous, gradual transitions across the full spectrum of autonomy levels, from direct teleoperation to full autonomy. To validate our approach, we conducted experiments to compare the performance of our proposed algorithm against two MPC-based shared autonomy methods. Compared to the baselines, our approach achieved reductions of at least 61% in object retrieval time, 44% in trajectory length, and 60% in human control input. Participants reported high perceived control, predictability, intent recognition, and responsiveness, along with low workload.
Figures & tables
Figure 1: Intent-Informed Model Predictive Control uses the entropy of the belief distribution derived from human intent inference to determine the control authority between the human operator and the system.
Figure 2: Methodology overview. Our approach combines intent inference using a Dynamic Bayesian Network (DBN) with Model Predictive Control (MPC) for adaptive shared autonomy. The DBN continuously updates beliefs on the goals based on operator gaze and robot motion. The MPC formulation uses the entropy of these beliefs to adjust the level of autonomy, ranging from direct teleoperation when entropy is high to full autonomy when entropy is low.
Parameter
Value
Parameter
Value
α
0.2
P
30I
T
10
Q
30I
ng
6
wrot
5
Table I: System Parameters
Figure 3: Experimental setup. a) The operator uses an Xbox controller to teleoperate the robot through a screen-based user interface. The eye tracker is mounted on the monitor. b) Robotic system. For the experiment, we use the left arm with the FinRay gripper. The right arm is not operational.
Figure 4: Experimental results. Our proposed method Intent-Informed MPC resulted in a) faster object retrieval time, b) lower trajectory length and c) lower human control input. Statistical significance ( p<0.001 ) is denoted by ***.
Figure 5: Time plot of entropy and target belief in a representative trial. As entropy decreases, the system increases the level of autonomy.
Question
Intent-MPC (Ours)
A-MPC
B-MPC
Intent vs A
Intent vs B
B vs A
Mean
SD
Mean
SD
Mean
SD
p -value
p -value
p -value
Q1 Control
5.65
1.27
3.10
1.37
5.80
1.01
<0.01
>0.05
<0.001
Q2 Predictability
6.35
0.75
2.80
1.28
6.35
0.67
<0.001
>0.05
<0.001
Q3 Intent Understanding
6.35
0.99
3.00
1.34
6.10
1.21
<0.001
>0.05
<0.01
Q4 Responsiveness
6.35
0.75
3.40
1.10
6.30
0.80
<0.01
>0.05
<0.01
Q5 Mental Demand
1.95
0.94
4.15
1.27
2.85
1.31
<0.01
>0.05
>0.05
Table II: Mean and standard deviation (7-point Likert scale) for each subjective question across control modes. Pairwise comparisons report Bonferroni-corrected p -values with significant differences ( p<0.05 ) shown in bold.
In mobile robot shared control, effectively understanding human motion intention is critical for seamless human-robot collaboration. This paper presents a novel shared control framework featuring planning-level intention prediction. A path replanning algorithm is designed to adjust the robot's desired trajectory according to inferred human intentions. To represent future motion intentions, we introduce the concept of an intention domain, which serves as a constraint for path replanning. The intention-domain prediction and path replanning problems are jointly formulated as a Markov Decision Process and solved through deep reinforcement learning. In addition, a Voronoi-based human trajectory generation algorithm is developed, allowing the model to be trained entirely in simulation without human participation or demonstration data. Extensive simulations and real-world user studies demonstrate that the proposed method significantly reduces operator workload and enhances safety, without compromising task efficiency compared with existing assistive teleoperation approaches.
We aim to address the challenge of teleoperating robotic arms for high-degree-of-freedom (high-DoF) manipulation tasks, which is cognitively demanding and error-prone, particularly when relying on low-bandwidth interfaces. We propose Robot Trajectron V3 (RT-V3), a probabilistic shared control framework designed for SE(3) grasping tasks. RT-V3 formulates shared control as Bayesian inference by learning a prior over user intent and combining it with real-time user commands to estimate the posterior intent distribution. The prior models user intent as a distribution over future trajectories conditioned on past robot dynamics and visual scene context. The intent prior is parameterized by a transformer-based conditional generative model that reasons over point clouds and candidate grasp poses, together with a factorized translation-rotation representation that improves learning efficiency in high-dimensional action spaces. During execution, RT-V3 continuously estimates the posterior distribution over future trajectories by combining the learned intent prior with a user-command likelihood derived from the observed control input, enabling continuous intent refinement and shared assistance. Comprehensive experiments demonstrate that RT-V3 achieves high accuracy in trajectory prediction and competitive performance in reactive planning. Furthermore, real-world user studies indicate that RT-V3 significantly outperforms baseline methods in terms of success rate and efficiency, while substantially reducing the user's physical and mental workload.
Pinhao Song, Zhongxi Li, Ze Fu +2
KU Leuven, Dept. Mechanical Engineering, Research unit Robotics, Automation and Mechatronics, B-3000 Leuven, Belgium. · KU Leuven, Dept. Electrical Engineering, Research unit Processing Speech and Images, B-3000 Leuven, Belgium.
Shared control often allocates robot authority based on confidence in inferred human intent, assuming reliable autonomous execution. When this assumption fails, high intent confidence can cause over-helping. We present a capability-aware shared-control framework in which a vision-language model (VLM) infers human intent and provides semantic-intent confidence, while a vision-language-action (VLA) policy generates autonomous actions. VLA capability confidence is estimated online from the dispersion and local instability of stochastic action trajectories. We design a nonlinear arbitration policy that combines Bayesian-filtered semantic-intent confidence with VLA capability confidence through a sigmoid mapping to adapt robot authority. Our evaluation combined VLM/VLA confidence assessment with a study involving 12 participants performing pick-and-place and bidirectional stacking under in-distribution and out-of-distribution conditions. The proposed method achieved the highest task success rate (92%), compared with manual teleoperation (83%), intent-only arbitration (44%), and fixed equal-weight blending (10%). It also achieved higher control friendliness and lower authority-weighted disagreement than both shared-control baselines. These results demonstrate the benefit of incorporating VLA capability into authority allocation to mitigate over-helping and improve shared-control performance.
Zhaoda Du, Michael Bowman, Xiaoli Zhang
Colorado School of Mines, Golden, CO 80401, USA. · University of Pennsylvania, Philadelphia, PA 19104, USA.