3 research outputs found
Collaborative Human-Robot Exploration via Implicit Coordination
This paper develops a methodology for collaborative human-robot exploration
that leverages implicit coordination. Most autonomous single- and multi-robot
exploration systems require a remote operator to provide explicit guidance to
the robotic team. Few works consider how to embed the human partner alongside
robots to provide guidance in the field. A remaining challenge for
collaborative human-robot exploration is efficient communication of goals from
the human to the robot. In this paper we develop a methodology that implicitly
communicates a region of interest from a helmet-mounted depth camera on the
human's head to the robot and an information gain-based exploration objective
that biases motion planning within the viewpoint provided by the human. The
result is an aerial system that safely accesses regions of interest that may
not be immediately viewable or reachable by the human. The approach is
evaluated in simulation and with hardware experiments in a motion capture
arena. Videos of the simulation and hardware experiments are available at:
https://youtu.be/7jgkBpVFIoE.Comment: 7 pages, 10 figures, to appear in the 2022 IEEE International
Symposium on Safety, Security, and Rescue Robotics (SSRR
Hierarchical Collision Avoidance for Adaptive-Speed Multirotor Teleoperation
This paper improves safe motion primitives-based teleoperation of a
multirotor by developing a hierarchical collision avoidance method that
modulates maximum speed based on environment complexity and perceptual
constraints. Safe speed modulation is challenging in environments that exhibit
varying clutter. Existing methods fix maximum speed and map resolution, which
prevents vehicles from accessing tight spaces and places the cognitive load for
changing speed on the operator. We address these gaps by proposing a high-rate
(10 Hz) teleoperation approach that modulates the maximum vehicle speed through
hierarchical collision checking. The hierarchical collision checker
simultaneously adapts the local map's voxel size and maximum vehicle speed to
ensure motion planning safety. The proposed methodology is evaluated in
simulation and real-world experiments and compared to a non-adaptive motion
primitives-based teleoperation approach. The results demonstrate the advantages
of the proposed teleoperation approach both in time taken and the ability to
complete the task without requiring the user to specify a maximum vehicle
speed.Comment: 8 pages, 8 figures, to be published in the 2022 IEEE International
Symposium on Safety, Security, and Rescue Robotics (SSRR
Mapping geographical inequalities in access to drinking water and sanitation facilities in low-income and middle-income countries, 2000–17
Abstract
Background: Universal access to safe drinking water and sanitation facilities is an essential human right, recognised in the Sustainable Development Goals as crucial for preventing disease and improving human wellbeing. Comprehensive, high-resolution estimates are important to inform progress towards achieving this goal. We aimed to produce high-resolution geospatial estimates of access to drinking water and sanitation facilities.
Methods: We used a Bayesian geostatistical model and data from 600 sources across more than 88 low-income and middle-income countries (LMICs) to estimate access to drinking water and sanitation facilities on continuous continent-wide surfaces from 2000 to 2017, and aggregated results to policy-relevant administrative units. We estimated mutually exclusive and collectively exhaustive subcategories of facilities for drinking water (piped water on or off premises, other improved facilities, unimproved, and surface water) and sanitation facilities (septic or sewer sanitation, other improved, unimproved, and open defecation) with use of ordinal regression. We also estimated the number of diarrhoeal deaths in children younger than 5 years attributed to unsafe facilities and estimated deaths that were averted by increased access to safe facilities in 2017, and analysed geographical inequality in access within LMICs.
Findings: Across LMICs, access to both piped water and improved water overall increased between 2000 and 2017, with progress varying spatially. For piped water, the safest water facility type, access increased from 40·0% (95% uncertainty interval [UI] 39·4–40·7) to 50·3% (50·0–50·5), but was lowest in sub-Saharan Africa, where access to piped water was mostly concentrated in urban centres. Access to both sewer or septic sanitation and improved sanitation overall also increased across all LMICs during the study period. For sewer or septic sanitation, access was 46·3% (95% UI 46·1–46·5) in 2017, compared with 28·7% (28·5–29·0) in 2000. Although some units improved access to the safest drinking water or sanitation facilities since 2000, a large absolute number of people continued to not have access in several units with high access to such facilities (>80%) in 2017. More than 253 000 people did not have access to sewer or septic sanitation facilities in the city of Harare, Zimbabwe, despite 88·6% (95% UI 87·2–89·7) access overall. Many units were able to transition from the least safe facilities in 2000 to safe facilities by 2017; for units in which populations primarily practised open defecation in 2000, 686 (95% UI 664–711) of the 1830 (1797–1863) units transitioned to the use of improved sanitation. Geographical disparities in access to improved water across units decreased in 76·1% (95% UI 71·6–80·7) of countries from 2000 to 2017, and in 53·9% (50·6–59·6) of countries for access to improved sanitation, but remained evident subnationally in most countries in 2017.
Interpretation: Our estimates, combined with geospatial trends in diarrhoeal burden, identify where efforts to increase access to safe drinking water and sanitation facilities are most needed. By highlighting areas with successful approaches or in need of targeted interventions, our estimates can enable precision public health to effectively progress towards universal access to safe water and sanitation