Real-Time Human-Adaptive Task Allocation for Multi-Human Multi-Robot Supervision
Authors: Seabin Lee, Sujeong Park, Nayoung Kim, Sungjin Park, Haechan Jung, Changjoo Nam
Organizations: Sogang University, Seoul, Korea. 1Dept. of Electronic Engineering. · Sogang University, Seoul, Korea. 2Dept. of Artificial Intelligence.
We propose a human-factor-aware method of allocating robot supervision tasks to multiple human operators. In scenarios where multiple operators occasionally teleoperate multiple robots to help the robots overcome difficulties, the allocation of the supervisory control tasks to humans needs to consider the real-time cognitive states of individual operators. However, most existing methods assume fixed supervisory capacity per operator and overlook fluctuations in the human factors such as workload and fatigue. As a result, workload distribution can be unbalanced where some operators become overloaded while the others remain underused. Our method dynamically regulates supervisory capacity and allocates tasks in a way that maintains balanced mental workload, prevents overload, and improves overall team performance. The allocation method uses a greedy strategy that minimizes estimated operator workloads with task prioritization. Robots are assigned to operators by reflecting their current supervisory capacity where the required effort depends on the types of tasks. In the user study, the analysis across predefined time intervals shows that the proposed method consistently achieves higher performance and lower behavioral signs of fatigue compared to a baseline method that does not consider human factors. These results highlight adaptive capacity adjustment as an effective preventive mechanism for sustaining operator performance in long-duration, high-demand settings.
Figures & tables
Figure 1 : Overview of HAMA. Inputs include NASA-TLX workload, subjective fatigue, blink count, success count, and AOI dwell time. The system updates operator capacity by predefined time intervals and assigns robots online based on AOI dwell time. Operators perform teleoperation for robots that are in deadlock or help-signal situations. The diagram shows three operators and the flow from sensing to assignment.
Figure 2 : Overview of the experimental setup. (a) Full view of the simulated warehouse environment. Multiple robots navigate passages to perform tasks such as deadlock resolution and charging station docking. (b) Example of a deadlock situation involving multiple robots in a narrow passage. (c) Docking zone with charging indicators. Robots must request help to align correctly for docking. Keyboard control scheme is shown at the bottom-left, and the operator display at the bottom-center.
Figure 3 : Example of a deadlock cluster in a narrow warehouse passage. Green check marks indicate robots identified as boundary robots, based on convex hull location and directional clearance. Robots marked with the red alert icon are internal to the deadlock cluster and cannot move until boundary robots are cleared.
Figure 4 : Study timeline. After briefing, 2-back tests, and eye-tracker calibration, teams completed two allocation conditions in counterbalanced order. Each condition consisted of 10 repetitions of a 4-minute supervision task followed by a brief survey. A scheduled break separated the two blocks. Total time per team was about 90 min ( ≈ 80 min task time).
Figure 5 : View of the VR control interface as seen by an operator. Multiple robot camera feeds are shown. AOI dwell time and gaze rays were only visible during debugging, not in the actual experiment.
Condition
HAMA
Baseline
Capacity update
✓
×
Attention-based weighting
✓
×
Boundary-based reallocation
✓
✓
Table I : Allocation features in HAMA and baseline conditions
Metric
Method
Session
3
4
5
6
7
8
9
10
Overall
NASA-TLX ↓
HAMA
29.03 ± 7.65
29.73 ± 7.73
30.43 ± 8.85
30.80 ± 9.54
32.30 ± 8.78
31.60 ± 9.03
31.57 ± 9.54
32.00 ± 9.31
30.93 ± 8.77
Baseline
30.03 ± 7.96
30.93 ± 8.10
30.53 ± 8.52
30.77 ± 8.89
31.17 ± 8.96
31.03 ± 9.60
30.87 ± 9.80
31.87 ± 10.16
30.90 ± 8.91
Cognitive Fatigue ↓
HAMA
4.07 ± 2.02
4.57 ± 2.03
4.73 ± 2.16
5.17 ± 2.38
5.67 ± 2.50
5.67 ± 2.47
5.73 ± 2.43
5.57 ± 2.33
5.15 ± 2.34
Baseline
4.53 ± 2.18
4.90 ± 2.20
5.20 ± 2.44
5.53 ± 2.53
5.90 ± 2.59
5.93 ± 2.60
6.10 ± 2.38
6.23 ± 2.51
5.54 ± 2.47
Blink Count ↓
HAMA
44.47 ± 42.33
49.30 ± 46.65
53.90 ± 47.63
58.47 ± 56.60
58.90 ± 58.75
62.47 ± 53.67
58.80 ± 56.87
61.03 ± 53.62
55.92 ± 51.86
Table II : Session-wise mean ± SD (Sessions 3–10). Higher is better for Performance ( ↑ ), and lower is better for the other measures ( ↓ ).
Metric
Effect
F
ηp2
post - hoc
NASA-TLX
Session
3.342 ∗
0.504
3<7,10
Algorithm
0.001
0
-
Cognitive Fatigue
Session
8.182 ∗∗∗
0.713
4,5<6 3<4,5<7,8,9,10
Algorithm
1.546
0.051
-
Blink Count
Session
1.558
0.322
-
Algorithm
6.077 ∗
0.173
-
Table III : Results of two-way RM-ANOVA in experiment.
Figure 6 : Session-wise trends (left) and overall mean with SD (right) for NASA-TLX, Cognitive Fatigue, Blink Count, Performance, and Capacity. Panels are stacked from top to bottom. Asterisks mark a significant main effect of the algorithm for Blink Count and Performance ( p<0.05 ).
Figure 7 : Plot of changes in the average relative difficulty ratio by session.
Effective human-robot teaming is crucial for the practical deployment of robots in human workspaces. However, optimizing joint human-robot plans remains a challenge due to the difficulty of modeling individualized human capabilities and preferences. While prior research has leveraged the multi-cycle structure of domains like manufacturing to learn an individual's tendencies and adapt plans over repeated interactions, these techniques typically consider task-level and motion-level adaptation in isolation. Task-level methods optimize allocation and scheduling but often ignore spatial interference in close-proximity scenarios; conversely, motion-level methods focus on collision avoidance while ignoring the broader task context. This paper introduces RAPIDDS, a framework that unifies these approaches by modeling an individual's spatial behavior (motion paths) and temporal behavior (time required to complete tasks) over multiple cycles. RAPIDDS then jointly adapts task schedules and steers diffusion models of robot motions to maximize efficiency and minimize proximity accounting for these individualized models. We demonstrate the importance of this dual adaptation through an ablation study in simulation and a physical robot scenario using a 7-DOF robot arm. Finally, we present a user study (n=32) showing significant plan improvement compared to non-adaptive systems across both objective metrics, such as efficiency and proximity, and subjective measures, including fluency and user preference. See this paper's companion video at: https://youtu.be/55Q3lq1fINs.
Alex Cuellar, Michael Hagenow, Julie Shah
MIT CSAIL · UW Madison Department of Computer Science
Robots deployed in dynamic environments must contend with environment-driven changes that reshape computation at runtime: new tasks may appear, precedence relations can shift, and overall workload structure evolves, all of which degrade performance, especially when multi-task inference is required under tight resource and real-time budgets. We present RED, a real-time scheduling framework for multi-task deep neural network workloads on resource-constrained robotic platforms that adapts to Robotic Environmental Dynamics (RED) while preserving end-to-end timing guarantees under modeling assumptions. The core of RED is a deadline-aware scheduler that assigns intermediate sub-deadlines, allowing it to accommodate evolving computation graphs and asynchronous inference induced by unpredictable conditions. The framework also supports flexible deployment of MIMONet (multi-input multi-output neural networks), commonly used in multi-tasking robots to alleviate memory pressure through weight sharing. RED explicitly leverages this shared-parameter property via a workload refinement and graph-reconstruction procedure that aligns MIMONet structure with schedulability requirements, improving compatibility and efficiency. We implement RED on NVIDIA Jetson family platforms and on an Apple M-series MacBook and evaluate it on navigation-oriented workloads representative of real robotic scenarios. Experiments show consistent gains over existing methods in throughput, deadline satisfaction, robustness to interference, adaptability, and runtime overhead.
Zexin Li, Tao Ren, Johnathan Liu +2
University of California, Riverside, USA · University of Pittsburgh, USA · University of Maryland, Baltimore County, USA +1
The introduction of human-robot collaboration (HRC) in industrial assembly operations is revolutionizing the manufacturing landscape. In this evolving environment, operators are required to seamlessly coordinate their manual tasks with real-time task information and robotic behaviors. These demands fluctuate during operation, yet conventional workload assessments depend on body-worn physiological sensors that complicate practical deployment. Here, we present a vision-based attention--action framework for continuous and interpretable workload-related assessment in HRC assembly. The framework combines RGB-D observations with robot states and calibrated task-related areas to construct a temporally confirmed representation of operator behavior. This representation identifies where task demand is concentrated and explains how it develops when attention and action diverge, the task context changes, or the operator hesitates. We evaluated the framework in a three-level collaborative gearbox assembly experiment with ten participants, using subjective ratings and synchronized physiological signals as independent references. Raw NASA-TLX ratings confirmed increasing perceived workload across conditions, with significant effects on overall workload and its mental and temporal dimensions. The vision-derived HRC-CWL output was significantly associated with ECG-derived features in seven of nine participants with complete correlation data. Synchronized interaction episodes further showed temporal correspondence between detected hesitation and physiological activity. Real-time deployment demonstrated that the framework can operate without requiring operators to wear additional sensors. These findings support HRC-CWL as an interpretable behavioral proxy for cognitive ergonomics analysis and adaptive robot assistance, rather than a direct psychophysiological measure of workload.
Junyan Xiong, Naiyi Feng, Xingke Xia +3
Smart Manufacturing Thrust, System Hub, The Hong Kong University of Science and Technology (Guangzhou), Guangzhou, China · College of Future Technology, The Hong Kong University of Science and Technology (Guangzhou), Guangzhou, China