39 research outputs found
VFH+ based shared control for remotely operated mobile robots
This paper addresses the problem of safe and efficient navigation in remotely
controlled robots operating in hazardous and unstructured environments; or
conducting other remote robotic tasks. A shared control method is presented
which blends the commands from a VFH+ obstacle avoidance navigation module with
the teleoperation commands provided by an operator via a joypad. The presented
approach offers several advantages such as flexibility allowing for a
straightforward adaptation of the controller's behaviour and easy integration
with variable autonomy systems; as well as the ability to cope with dynamic
environments. The advantages of the presented controller are demonstrated by an
experimental evaluation in a disaster response scenario. More specifically,
presented evidence show a clear performance increase in terms of safety and
task completion time compared to a pure teleoperation approach, as well as an
ability to cope with previously unobserved obstacles.Comment: 8 pages,6 figure
A Hierarchical Variable Autonomy Mixed-Initiative Framework for Human-Robot Teaming in Mobile Robotics
This paper presents a Mixed-Initiative (MI) framework for addressing the
problem of control authority transfer between a remote human operator and an AI
agent when cooperatively controlling a mobile robot. Our Hierarchical
Expert-guided Mixed-Initiative Control Switcher (HierEMICS) leverages
information on the human operator's state and intent. The control switching
policies are based on a criticality hierarchy. An experimental evaluation was
conducted in a high-fidelity simulated disaster response and remote inspection
scenario, comparing HierEMICS with a state-of-the-art Expert-guided
Mixed-Initiative Control Switcher (EMICS) in the context of mobile robot
navigation. Results suggest that HierEMICS reduces conflicts for control
between the human and the AI agent, which is a fundamental challenge in both
the MI control paradigm and also in the related shared control paradigm.
Additionally, we provide statistically significant evidence of improved,
navigational safety (i.e., fewer collisions), LOA switching efficiency, and
conflict for control reduction.Comment: 6 pages, 4 figures, ICHMS 2022, First two Authors contributed equall
Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field
Robot Vitals and Robot Health: Towards Systematically Quantifying Runtime Performance Degradation in Robots Under Adverse Conditions
This paper addresses the problem of automatically detecting and quantifying
performance degradation in remote mobile robots during task execution. A robot
may encounter a variety of uncertainties and adversities during task execution,
which can impair its ability to carry out tasks effectively and cause its
performance to degrade. Such situations can be mitigated or averted by timely
detection and intervention (e.g., by a remote human supervisor taking over
control in teleoperation mode). Inspired by patient triaging systems in
hospitals, we introduce the framework of "robot vitals" for estimating overall
"robot health". A robot's vitals are a set of indicators that estimate the
extent of performance degradation faced by a robot at a given point in time.
Robot health is a metric that combines robot vitals into a single scalar value
estimate of performance degradation. Experiments, both in simulation and on a
real mobile robot, demonstrate that the proposed robot vitals and robot health
can be used effectively to estimate robot performance degradation during
runtime.Comment: 8 Page
Trust, shared understanding and locus of control in mixed-initiative robotic systems
This paper investigates how trust, shared understanding between a human
operator and a robot, and the Locus of Control (LoC) personality trait, evolve
and affect Human-Robot Interaction (HRI) in mixed-initiative robotic systems.
As such systems become more advanced and able to instigate actions alongside
human operators, there is a shift from robots being perceived as a tool to
being a team-mate. Hence, the team-oriented human factors investigated in this
paper (i.e. trust, shared understanding, and LoC) can play a crucial role in
efficient HRI. Here, we present the results from an experiment inspired by a
disaster response scenario in which operators remotely controlled a mobile
robot in navigation tasks, with either human-initiative or mixed-initiative
control, switching dynamically between two different levels of autonomy:
teleoperation and autonomous navigation. Evidence suggests that operators
trusted and developed an understanding of the robotic systems, especially in
mixed-initiative control, where trust and understanding increased over time, as
operators became more familiar with the system and more capable of performing
the task. Lastly, evidence and insights are presented on how LoC affects HRI.Comment: Pre-print of the accepted paper in IEEE RO-MAN 2021 (typo in Table 1
fixed!