111 research outputs found
Safe and Efficient Exploration of Human Models During Human-Robot Interaction
Many collaborative human-robot tasks require the robot to stay safe and work
efficiently around humans. Since the robot can only stay safe with respect to
its own model of the human, we want the robot to learn a good model of the
human in order to act both safely and efficiently. This paper studies methods
that enable a robot to safely explore the space of a human-robot system to
improve the robot's model of the human, which will consequently allow the robot
to access a larger state space and better work with the human. In particular,
we introduce active exploration under the framework of energy-function based
safe control, investigate the effect of different active exploration
strategies, and finally analyze the effect of safe active exploration on both
analytical and neural network human models.Comment: IROS 202
Multimodal Safe Control for Human-Robot Interaction
Generating safe behaviors for autonomous systems is important as they
continue to be deployed in the real world, especially around people. In this
work, we focus on developing a novel safe controller for systems where there
are multiple sources of uncertainty. We formulate a novel multimodal safe
control method, called the Multimodal Safe Set Algorithm (MMSSA) for the case
where the agent has uncertainty over which discrete mode the system is in, and
each mode itself contains additional uncertainty. To our knowledge, this is the
first energy-function-based safe control method applied to systems with
multimodal uncertainty. We apply our controller to a simulated human-robot
interaction where the robot is uncertain of the human's true intention and each
potential intention has its own additional uncertainty associated with it,
since the human is not a perfectly rational actor. We compare our proposed safe
controller to existing safe control methods and find that it does not impede
the system performance (i.e. efficiency) while also improving the safety of the
system
Learning Image-Conditioned Dynamics Models for Control of Under-actuated Legged Millirobots
Millirobots are a promising robotic platform for many applications due to
their small size and low manufacturing costs. Legged millirobots, in
particular, can provide increased mobility in complex environments and improved
scaling of obstacles. However, controlling these small, highly dynamic, and
underactuated legged systems is difficult. Hand-engineered controllers can
sometimes control these legged millirobots, but they have difficulties with
dynamic maneuvers and complex terrains. We present an approach for controlling
a real-world legged millirobot that is based on learned neural network models.
Using less than 17 minutes of data, our method can learn a predictive model of
the robot's dynamics that can enable effective gaits to be synthesized on the
fly for following user-specified waypoints on a given terrain. Furthermore, by
leveraging expressive, high-capacity neural network models, our approach allows
for these predictions to be directly conditioned on camera images, endowing the
robot with the ability to predict how different terrains might affect its
dynamics. This enables sample-efficient and effective learning for locomotion
of a dynamic legged millirobot on various terrains, including gravel, turf,
carpet, and styrofoam. Experiment videos can be found at
https://sites.google.com/view/imageconddy
Towards Proactive Safe Human-Robot Collaborations via Data-Efficient Conditional Behavior Prediction
We focus on the problem of how we can enable a robot to collaborate
seamlessly with a human partner, specifically in scenarios like collaborative
manufacturing where prexisting data is sparse. Much prior work in human-robot
collaboration uses observational models of humans (i.e. models that treat the
robot purely as an observer) to choose the robot's behavior, but such models do
not account for the influence the robot has on the human's actions, which may
lead to inefficient interactions. We instead formulate the problem of optimally
choosing a collaborative robot's behavior based on a conditional model of the
human that depends on the robot's future behavior. First, we propose a novel
model-based formulation of conditional behavior prediction that allows the
robot to infer the human's intentions based on its future plan in data-sparse
environments. We then show how to utilize a conditional model for proactive
goal selection and path generation around human collaborators. Finally, we use
our proposed proactive controller in a collaborative task with real users to
show that it can improve users' interactions with a robot collaborator
quantitatively and qualitatively
Multi-Agent Strategy Explanations for Human-Robot Collaboration
As robots are deployed in human spaces, it's important that they are able to
coordinate their actions with the people around them. Part of such coordination
involves ensuring that people have a good understanding of how a robot will act
in the environment. This can be achieved through explanations of the robot's
policy. Much prior work in explainable AI and RL focuses on generating
explanations for single-agent policies, but little has been explored in
generating explanations for collaborative policies. In this work, we
investigate how to generate multi-agent strategy explanations for human-robot
collaboration. We formulate the problem using a generic multi-agent planner,
show how to generate visual explanations through strategy-conditioned landmark
states and generate textual explanations by giving the landmarks to an LLM.
Through a user study, we find that when presented with explanations from our
proposed framework, users are able to better explore the full space of
strategies and collaborate more efficiently with new robot partners
Image-guided Retrieval of Foreign Body in the Abdomen - A Case Report
The presence of retained surgical blade as a foreign body is uncommon and poses significant patient safety challenge issues. Most common etiologies for the presence of such foreign bodies are accidental, traumatic, or iatrogenic. Here, we report a successful management of the case with a rare foreign body in the abdomen, that is, surgical blade accidentally left during pigtail procedure of the liver abscess. Most of the iatrogenic injuries are preventable. In our case, a misfit of a blade in the handle might have been responsible for the complication. The use of radiological guidance for localization and removal of the foreign bodies embedded in the soft tissues is well established. With imaging guidance retrieval of a foreign body in the abdomen, laparotomy was prevented and facilitated early recovery
Prevalence of oral soft tissue lesions in Vidisha
<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to determine the prevalence of oral soft tissue lesions in patients and to assess their clinicopathological attributes. 3030 subjects belonging to a semi-urban district of Vidisha in Central India were screened. Patients were examined with an overhead examination light and those who were identified with a questionable lesion underwent further investigations. Statistical analysis was done using the SPSS software.</p> <p>Findings</p> <p>8.4 percent of the population studied had one or more oral lesions, associated with prosthetic use, trauma and tobacco consumption. With reference to the habit of tobacco use, 635(21%) were smokers, 1272(42%) tobacco chewers, 341(11%) smokers and chewers, while 1464(48%) neither smoked nor chewed. 256 patients were found to have significant mucosal lesions. Of these, 216 cases agreed to undergo scalpel biopsy confirmation. 88 had leukoplakia, 21 had oral submucous fibrosis, 9 showed smoker's melanosis, 6 patients had lichen planus, 17 had dysplasia, 2 patients had squamous cell carcinoma while there was 1 patient each with lichenoid reaction, angina bullosa hemorrhagica, allergic stomatitis and nutritional stomatitis.</p> <p>Conclusions</p> <p>The findings in this population reveal a high prevalence of oral soft tissue lesions and a rampant misuse of variety of addictive substances in the community. Close follow up and systematic evaluation is required in this population. There is an urgent need for awareness programs involving the community health workers, dentists and allied medical professionals.</p
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