Renchi Zhang
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6 records found
1
This thesis investigated where alignment and misalignment occur between humans and AI-driven robots, and how human-robot interaction should be designed for complementary collaboration. This thesis adopts the vocabulary of Wickens’ Multiple Resource Theory, which distinguishes processing stages (perception, cognition, responding), processing modalities (visual and auditory), and processing codes (spatial, verbal). Four empirical studies targeted different processing stages and progressed in platform complexity and realism.
Across the four studies, a combined 2,292 participants generated evidence that misalignment can occur at every information-processing stage. Three overarching findings are extracted. First, outcome-level results alone are insufficient for detecting misalignment: high correlations in Chapter 2 masked different search mechanisms, and verbal fluency in Chapter 4 masked shallow reasoning. Second, as the AI system becomes more automated, the human role changes from direct operator to supervisor, from commanding every movement (Chapter 3), through evaluating automated perception and strategy (Chapter 4), to diagnosing complete LLM-generated plans (Chapter 5). Third, the quality of collaboration depends on how cognition is distributed, not only on the absolute capability of either partner: voice control freed spatial resources while gestures overloaded them (Chapter 3), and students learned to redistribute cognitive work based on model capability and task difficulty (Chapter 5).
This thesis also has limitations. The studies focused heavily on the visual modality; haptic and auditory modalities were not explicitly investigated. Each study concerned a specific domain and a relatively homogeneous participant population. Whether the documented forms of misalignment transfer to other human-robot-interaction domains, more complex environments, and more diverse populations requires further investigation. Nonetheless, the findings support a set of design principles: use modality switching to offload overloaded cognitive resources, expose AI uncertainty rather than only AI outcomes, provide calibration training before deployment, and design function allocation as dynamic instead of static. ...
This thesis investigated where alignment and misalignment occur between humans and AI-driven robots, and how human-robot interaction should be designed for complementary collaboration. This thesis adopts the vocabulary of Wickens’ Multiple Resource Theory, which distinguishes processing stages (perception, cognition, responding), processing modalities (visual and auditory), and processing codes (spatial, verbal). Four empirical studies targeted different processing stages and progressed in platform complexity and realism.
Across the four studies, a combined 2,292 participants generated evidence that misalignment can occur at every information-processing stage. Three overarching findings are extracted. First, outcome-level results alone are insufficient for detecting misalignment: high correlations in Chapter 2 masked different search mechanisms, and verbal fluency in Chapter 4 masked shallow reasoning. Second, as the AI system becomes more automated, the human role changes from direct operator to supervisor, from commanding every movement (Chapter 3), through evaluating automated perception and strategy (Chapter 4), to diagnosing complete LLM-generated plans (Chapter 5). Third, the quality of collaboration depends on how cognition is distributed, not only on the absolute capability of either partner: voice control freed spatial resources while gestures overloaded them (Chapter 3), and students learned to redistribute cognitive work based on model capability and task difficulty (Chapter 5).
This thesis also has limitations. The studies focused heavily on the visual modality; haptic and auditory modalities were not explicitly investigated. Each study concerned a specific domain and a relatively homogeneous participant population. Whether the documented forms of misalignment transfer to other human-robot-interaction domains, more complex environments, and more diverse populations requires further investigation. Nonetheless, the findings support a set of design principles: use modality switching to offload overloaded cognitive resources, expose AI uncertainty rather than only AI outcomes, provide calibration training before deployment, and design function allocation as dynamic instead of static.
Visual search is a fundamental cognitive ability. This study investigates whether Multimodal Large Language Models (MLLMs) exhibit human-like difficulty signatures in visual search tasks. We compared search performance of humans (n = 1,250) and MLLMs using identical 2D and 3D stimuli across different set sizes. Both groups showed efficient performance in feature searches, most clearly when the target had a unique color, but performance degradation in conjunction searches as set sizes increased. Additionally, we found strong correlations between human and MLLM error rates (ρ = 0.82), which suggests that MLLMs are sensitive to similar objective complexities, such as stimulus heterogeneity. However, differences were found as well: whereas humans invested extra search time to respond accurately on target-absent trials, MLLMs exhibited extreme present/absent response biases in complex searches. We conclude that MLLMs replicate high-level human performance signatures, yet their underlying computations differ significantly.
A review on machine learning in flexible surgical and interventional robots
Where we are and where we are going
Minimally Invasive Procedures (MIPs) emerged as an alternative to more invasive surgical approaches, offering patient benefits such as smaller incisions, less pain, and shorter hospital stay. In one class of MIPs, where natural body lumens or small incisions are used to access deeper anatomical locations, Flexible Surgical and Interventional Robots (FSIRs) such as catheters and endoscopes are widely used. Due to their flexible and compliant nature, FSIRs can be inserted via natural orifices or small incisions, then moved towards hard-to-reach targets to perform interventional tasks. However, existing FSIRs are confronted with challenges in sensing, control, and navigation. These issues stem from the robot's non-linear behavior and the intricate nature of the lumens, where accurately modeling the complex interactions and disturbances proves to be exceptionally difficult. The rapid advances in Machine Learning (ML) have facilitated the widespread adoption of ML techniques in FSIRs. This article provides an overview of these efforts by first introducing a classification of existing ML algorithms, including traditional ML methods and modern Deep Learning (DL) approaches, commonly used in FSIRs. Next, the use of ML algorithms is surveyed per sub-domain, namely for perception, modeling, control, and navigation. Trends, popularity, strengths, and/or limitations of different ML algorithms are analyzed. The different roles that ML plays among tasks are investigated and described. Finally, discussions are conducted on the limitations and the prospects of ML in MIPs.