Ella Atkins
University of Michigan, Aerospace Engineering, Faculty Member
Research Interests:
Research Interests:
This paper proposes a novel multi-objective route planning approach within the framework of a Vehicle-to-Cloud-to-Vehicle (V2C2V) architecture. Time and road risk index (RRI) are both considered as metrics. To evaluate road segment risk,... more
This paper proposes a novel multi-objective route planning approach within the framework of a Vehicle-to-Cloud-to-Vehicle (V2C2V) architecture. Time and road risk index (RRI) are both considered as metrics. To evaluate road segment risk, an accident database from the Highway Safety Information System (HSIS) is processed to build a comprehensive road risk assessment model. Route planning is formulated as a multi-objective network flow problem and further reduced to a Mixed Integer Programming (MIP) problem. A real-world case study, route planning through the city of Columbus, Ohio, is presented. The Vehicle-to-Cloud-to-Vehicle (V2C2V) based implementation of our safety-based route planning approach is proposed to facilitate access to real-time information and computing resources.
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This paper considers the problem of vehicle suspension control from the perspective of a Vehicle-to-Cloud-to-Vehicle (V2C2V) distributed implementation. A simplified variant of the problem is examined based on the linear quarter-car model... more
This paper considers the problem of vehicle suspension control from the perspective of a Vehicle-to-Cloud-to-Vehicle (V2C2V) distributed implementation. A simplified variant of the problem is examined based on the linear quarter-car model of semi-active suspension dynamics. Road disturbance is modeled as a combination of a known road profile, an unmeasured stochastic road profile and potholes. Suspension response when the vehicle hits the pothole is modeled as an impulsive change in wheel velocity with magnitude linked to physical characteristics of the pothole and of the vehicle. The problem of selecting the optimal damping mode from a finite set of damping modes is considered, based on road profile data. The information flow and V2C2V implementation are defined based on partitioning the computations and data between the vehicle and the cloud. A simulation example is presented.
Research Interests:
Research Interests:
Research Interests: Engineering and Elsevier
To react appropriately in hard real-time environments, a system must either employ fast dynamic planning or recall a pre-built reactive response. For complex problems, real-time, accurate dynamic planning may be impossible, and the... more
To react appropriately in hard real-time environments, a system must either employ fast dynamic planning or recall a pre-built reactive response. For complex problems, real-time, accurate dynamic planning may be impossible, and the complete set of possible reactions may be too large ...
Research Interests: Engineering and Real Time
Complex system automation is possible only through careful application of algorithms from several research communities, including artificial intelligence, real-time, and control. However, the complexity and focus of the technologies... more
Complex system automation is possible only through careful application of algorithms from several research communities, including artificial intelligence, real-time, and control. However, the complexity and focus of the technologies required from each community depend on the domain ...
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Approximate models of world state transitions are necessary when building plans for complex systems operating in dynamic environments. External event probabilities can depend on state feature values as well as time spent in that... more
Approximate models of world state transitions are necessary when building plans for complex systems operating in dynamic environments. External event probabilities can depend on state feature values as well as time spent in that particular state. We assign ...
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The degree to which a planner succeeds and meets response deadlines depends on the correctness and completeness of its models which describe events and actions that change the world state. It is often unrealistic to expect perfect models,... more
The degree to which a planner succeeds and meets response deadlines depends on the correctness and completeness of its models which describe events and actions that change the world state. It is often unrealistic to expect perfect models, so a planner must be able ...
Research Interests:
Research Interests:
Current Flight Management Systems (FMS) can autonomously fly an aircraft from takeoff through landing but may not provide robust operation to anomalous events. We present an adaptive trajectory planner capable of dynamically adjusting its... more
Current Flight Management Systems (FMS) can autonomously fly an aircraft from takeoff through landing but may not provide robust operation to anomalous events. We present an adaptive trajectory planner capable of dynamically adjusting its world model and re-computing ...
Research Interests:
Autonomous robots will provide crucial support for astronauts aboard the space station, during extravehicular activities (EVA), and on planetary surfaces. To be useful, a robotic assistant should be capable of autonomously executing... more
Autonomous robots will provide crucial support for astronauts aboard the space station, during extravehicular activities (EVA), and on planetary surfaces. To be useful, a robotic assistant should be capable of autonomously executing commands, safely following an astronaut, and operating under human control. In this paper, we outline an adjustable autonomy architecture for such an assistant and describe our efforts toward
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Page 1. 1 Longitudinal-Plane Simultaneous Non-Interfering Approach Trajectory Design for Noise Minimization Gaurav Gopalan♦ Min Xue♦ Ella Atkins* Fredric H. Schmitz£ Alfred E. Gessow Rotorcraft Center University of Maryland at College... more
Page 1. 1 Longitudinal-Plane Simultaneous Non-Interfering Approach Trajectory Design for Noise Minimization Gaurav Gopalan♦ Min Xue♦ Ella Atkins* Fredric H. Schmitz£ Alfred E. Gessow Rotorcraft Center University of Maryland at College Park College Park, MD 20742 ...
We describe the Ranger robotic system and its autonomous hazard control system, which is designed to meet the stringent criteria imposed on space shuttle payloads. Mature Ranger systems have enabled evaluation of telerobotic servicing... more
We describe the Ranger robotic system and its autonomous hazard control system, which is designed to meet the stringent criteria imposed on space shuttle payloads. Mature Ranger systems have enabled evaluation of telerobotic servicing tasks in a variety of 1-g and neutral buoyancy environments. These evaluations have included rigorous testing with operators that ranged from experienced system designers to small
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Spacecraft formation flight may increase data coverage area and accuracy for a myriad of space -based experiments. To prevent ground operations support from scaling with number of satellites, we propose a control architecture that... more
Spacecraft formation flight may increase data coverage area and accuracy for a myriad of space -based experiments. To prevent ground operations support from scaling with number of satellites, we propose a control architecture that describes a formation as a virtual body, such that the operator controls the group as if it were a single entity. We overview the components of
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Research Interests: Engineering and Aircraft
There is often seen in the literature a disconnect between higher-level artificial intelligence and lower-level controls research. Too often, path planners do not account for the physical capabilities of the agents that will be following... more
There is often seen in the literature a disconnect between higher-level artificial intelligence and lower-level controls research. Too often, path planners do not account for the physical capabilities of the agents that will be following their paths. Similarly, the best controllers available need to be given trajectories from somewhere. This work presents a combined architecture that links a high-level cognitive
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This paper presents a framework based on stochastic dynamic programming that facilitates the implementation of collaborative fault detection through conflict resolution. A conflict arises when two fault detectors draw opposing conclusions... more
This paper presents a framework based on stochastic dynamic programming that facilitates the implementation of collaborative fault detection through conflict resolution. A conflict arises when two fault detectors draw opposing conclusions regarding the presence of a fault. We use stochastic dynamic programming to optimally resolve conflicts and to control data gathering actions that can improve decision-making. Since stochastic dynamic programming
Research Interests:
Research Interests: Engineering and Aircraft
... Action-2 Test2-1, Test2-2,
TAP2 Action-3 Test3-1, Test3-2,
TAP3 Action-4 Test4-1, Test4-2,
TAP4 Action-5 Test5-1, Test5-2,
TAP5 Action-6 Test6-1, Test6-2,
TAP6 Action-7 Test7-1, Test7-2,
TAP7 guaranteed best-effort Cyclic... more
... Action-2 Test2-1, Test2-2,
TAP2 Action-3 Test3-1, Test3-2,
TAP3 Action-4 Test4-1, Test4-2,
TAP4 Action-5 Test5-1, Test5-2,
TAP5 Action-6 Test6-1, Test6-2,
TAP6 Action-7 Test7-1, Test7-2,
TAP7 guaranteed best-effort Cyclic Schedule: ...
... Planning Experts Ella Atkins, Gina Moylan, Aaron Hoskins University of Maryland, Space Systems Laboratory 382 Technology Drive College Park, MD, 20740 301-405-1124 {ella | gmoylan | ahoskins} @ssl.umd.edu ... [16] Zack Butler and... more
... Planning Experts Ella Atkins, Gina Moylan, Aaron Hoskins University of Maryland, Space Systems Laboratory 382 Technology Drive College Park, MD, 20740 301-405-1124 {ella | gmoylan | ahoskins} @ssl.umd.edu ... [16] Zack Butler and Daniela Rus, Distributed motion ...
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Research Interests:
Research Interests:
Research Interests:
ABSTRACT Unmanned Ground Vehicles (UGVs) face many mobility challenges as they operate in unstructured environments. In addition to insurmountable obstacles, UGVs can lose traction and slip, reducing maneuverability and potentially... more
ABSTRACT Unmanned Ground Vehicles (UGVs) face many mobility challenges as they operate in unstructured environments. In addition to insurmountable obstacles, UGVs can lose traction and slip, reducing maneuverability and potentially causing collisions with obstacles. This paper develops a dynamic model of a differentially-driven ground robot with lateral and longitudinal slip, using a ground friction model from the literature. A novel switching control system, with velocity input commands, is also presented. The controller switches from PID control to a trajectory planning mode when the robot begins to slip or when the normal command would exceed the ground friction forces. The trajectory is planned and executed based on commanded velocities. Stability and robustness of the trajectory planning controller are discussed. This control law is compared in simulation to a PID controller, using the UGV model, on different surfaces. The traction controller drives the UGV closer to the desired path derived from the reference trajectories.