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This thesis presents an overview of virtual reality (VR)-based teleoperation and describes its benefits and several existing challenges to its implementation, as well as potential solutions to these challenges. VR-based teleoperation of robotic arms enables a user to control and maneuver the robotic system from a remote distance while immersed

This thesis presents an overview of virtual reality (VR)-based teleoperation and describes its benefits and several existing challenges to its implementation, as well as potential solutions to these challenges. VR-based teleoperation of robotic arms enables a user to control and maneuver the robotic system from a remote distance while immersed in a virtual environment that simulates the location site of the robot. By implementing VR-based teleoperation, we can send robotic arms operated by trained professionals into harsh and inaccessible environments, including the deep sea and outer space, to accomplish manipulation tasks that would otherwise be unsafe or impossible. Teleoperated robotic arms can also be used to remotely execute fine manipulation tasks such as surgery, for instance, to reduce contamination or to perform operations in places that lack the required medical services. In order to be able to reliably and comfortably use VR-based teleoperation, we need to focus on solving the challenges of latency and sensory loss. Since the teleoperator has a limited field of view and cannot rely on certain types of sensory information, they can feel disoriented and disconnected from the environment and robotic arm. Sensory information loss can be mitigated by simulating a wider field of view in the virtual environment, implementing additional sensors such as thermometers and gas detection sensors, and using data sonification techniques. Although it may not be possible to completely eliminate latency, the effects of latency can be reduced through the use of assistive interfaces that predict the trajectory of the robotic arm in real-time based on the teleoperator’s input movement using artificial intelligence (AI)-based predictive models. When visualized in the virtual environment, this predictive real-time feedback enables the user to immediately see the effects of their movements on the robotic arm, even though the arm’s actual motion is delayed due to latency, and thus avoid collisions and improve task performance. VR-based teleoperation can be enhanced with these proposed solutions to enable the user to complete the required manipulation task with high precision and to maneuver the robotic arm with reduced cognitive load.
ContributorsTrejo, Patricia (Author) / Berman, Spring (Thesis director) / Lee, Hyunglae (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2024-05
Description

The concept of entrainment broadly applies the locking of phases between 2 independent systems [17]. This physical phenomenon can be applied to modify neuromuscular movement in humans during bipedal locomotion. Gait entrainment to robotic devices have shown great success as alternatives to labor intensive methods of rehabilitation. By applying additional

The concept of entrainment broadly applies the locking of phases between 2 independent systems [17]. This physical phenomenon can be applied to modify neuromuscular movement in humans during bipedal locomotion. Gait entrainment to robotic devices have shown great success as alternatives to labor intensive methods of rehabilitation. By applying additional torque at the ankle joint, previous studies have exhibited consistent gait entrainment to both rigid and soft robotic devices. This entrainment is characterized by consistent phase locking of plantarflexion perturbations to the ‘push off’ event within the gait cycle. However, it is unclear whether such phase locking can be attributed to the plantarflexion assistance from the device or the sensory stimulus of movement at the ankle. To clarify the mechanism of entrainment, an experiment was designed to expose the user to a multitude of varying torques applied at the ankle to assist with plantar flexion. In this experiment, no significant difference in success of subject entrainment occurred when additional torque applied was greater than a detectable level. Force applied at the ankle varied from ~60N to ~130N. This resulted in successful entrainment ~88\% of the time at 98 N, with little to no increase in success as force increased thereafter. Alternatively, success of trials decreased significantly as force was reduced below this level, causing the perturbations to become undetectable by participants. Ultimately this suggests that higher levels of actuator pressure, and thus greater levels of torque applied to the foot, do not increase the likelihood of entrainment during walking. Rather, the results of this study suggest that proper detectable sensory stimulus is the true mechanism for entrainment.

ContributorsKruse, Anna (Author) / Lee, Hyunglae (Thesis director) / Berman, Spring (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2022-12
Description

This thesis presents the design and simulation of an energy efficient controller for a system of three drones transporting a payload in a net. The object ensnared in the net is represented as a mass connected by massless stiff springs to each drone. Both a pole-placement approach and an optimal

This thesis presents the design and simulation of an energy efficient controller for a system of three drones transporting a payload in a net. The object ensnared in the net is represented as a mass connected by massless stiff springs to each drone. Both a pole-placement approach and an optimal control approach are used to design a trajectory controller for the system. Results are simulated for a single drone and the three drone system both without and with payload.

ContributorsHayden, Alexander (Author) / Grewal, Anoop (Thesis director) / Berman, Spring (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Historical, Philosophical & Religious Studies, Sch (Contributor)
Created2022-05
Description

The future of driving is largely headed towards autonomous vehicles, and this is clear with companies such as Tesla, Waymo, and even tech giant Apple. Many professionals predict that autonomous vehicles will likely be commercially available and legal to use in some places by the late 2020s [15]. There are

The future of driving is largely headed towards autonomous vehicles, and this is clear with companies such as Tesla, Waymo, and even tech giant Apple. Many professionals predict that autonomous vehicles will likely be commercially available and legal to use in some places by the late 2020s [15]. There are some benefits to the rapid development of autonomous vehicle controllers, such as more independence for those who can’t drive due to impairments, the potential for reduced traffic, as well as possibly decreasing the number of accidents. Though these are promising prospects, there are ethical concerns regarding the implementation of such technology. The goal of this thesis is to provide an introductory literature review that discusses the history of autonomous vehicles, different levels of autonomy, ethical considerations in autonomous systems, and prior work on characterizing human driving behaviors and implementing these behaviors with autonomous vehicle controllers. Finally, recommendations are proposed for data collection on human driving behaviors in an ongoing NSF-funded project at Arizona State University, “Embodiment of Human Values Profiles in Autonomous Vehicles via Psychomimetic Controller Design.”

ContributorsYoung, Brittine (Author) / Berman, Spring (Thesis director) / Johnson, Kathryn (Committee member) / Barrett, The Honors College (Contributor) / Department of Physics (Contributor) / Historical, Philosophical & Religious Studies, Sch (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2022-05
Description
Within the scope of Humanitarian Assistance and Disaster Relief (HADR), this thesis reviews some major challenges during mass evacuations, illustrated by incidents during actual mass evacuation scenarios, and identifies several potential applications of autonomous unmanned aerial vehicles (UAVs) in the effort to ease the transition of evacuees out of a

Within the scope of Humanitarian Assistance and Disaster Relief (HADR), this thesis reviews some major challenges during mass evacuations, illustrated by incidents during actual mass evacuation scenarios, and identifies several potential applications of autonomous unmanned aerial vehicles (UAVs) in the effort to ease the transition of evacuees out of a disaster area. System requirements and example UAV platforms are identified for applications in which autonomous UAVs monitor traffic conditions along evacuation routes, distribute information to the public, and establish a communications network for first responders.
ContributorsTaylor, Zachary (Author) / Berman, Spring (Thesis director) / Gerber, Brian (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2022-05
Description
A swarm of unmanned aerial vehicles (UAVs) has many potential applications including disaster relief, search and rescue, and area surveillance. A critical factor to a UAV swarm’s success is its ability to collectively locate and pursue targets determined to be of high quality with minimal and decentralized communication. Prior work

A swarm of unmanned aerial vehicles (UAVs) has many potential applications including disaster relief, search and rescue, and area surveillance. A critical factor to a UAV swarm’s success is its ability to collectively locate and pursue targets determined to be of high quality with minimal and decentralized communication. Prior work has investigated nature-based solutions to this problem, in particular the behavior of honeybees when making decisions on future nest sites. A UAV swarm may mimic this behavior for similar ends, taking advantage of widespread sensor coverage induced by a large population. To determine whether the proven success of honeybee strategies may still be found in UAV swarms in more complex and difficult conditions, a series of simulations were created in Python using a behavior modeled after the work of Cooke et al. UAV and environmental properties were varied to determine the importance of each to the success of the swarm and to find emergent behaviors caused by combinations of variables. From the simulation work done, it was found that agent population and lifespan were the two most important factors to swarm success, with preference towards small teams with long-lasting UAVs.
ContributorsGao, Max (Author) / Berman, Spring (Thesis director) / Pavlic, Theodore (Committee member) / Barrett, The Honors College (Contributor) / College of Integrative Sciences and Arts (Contributor) / Engineering Programs (Contributor)
Created2023-05
Description
In order to refine autonomous exploratory movement planning schemes, an approach must be developed that accounts for valuable information other than that gained from map filling. To this end, the goal of this thesis is divided into two parts. The first is to develop a technique for categorizing objects detected

In order to refine autonomous exploratory movement planning schemes, an approach must be developed that accounts for valuable information other than that gained from map filling. To this end, the goal of this thesis is divided into two parts. The first is to develop a technique for categorizing objects detected by an autonomous exploratory robot and assigning them a score based on their interest value. The second is an attempt to develop a method of integrating this technique into a navigation algorithm in order to refine the movements of a robot or robots to maximize the efficiency of information gain. The intention of both of these components is to provide a method of refining the navigation scheme applied to autonomous exploring robots and maximize the amount of information they can gather in deployments where they face significant resource or functionality constraints. To this end this project is divided into two main sections: a shape-matching technique and a simulation in in which to implement this technique. The first section was accomplished by combining concepts from information theory, principal component analysis, and the eigenfaces algorithm to create an effective matching technique. The second was created with inspiration from existing navigation algorithms. Once these components were determined to be functional, a testing regime was applied to determine their capabilities. The testing regime was also divided into two parts. The tests applied to the matching technique were first to demonstrate that it functions under ideal conditions. After testing was conducted under ideal conditions, the technique was tested under non-ideal conditions. Additional tests were run to determine how the system responded to changes in the coefficients and equations that govern its operation. Similarly, the simulation component was initially tested under normal conditions to determine the base effectiveness of the approach. After these tests were conducted, alternative conditions were tested to evaluate the effects of modifying the implementation technique. The results of these tests indicated a few things. The first series of tests confirmed that the matching technique functions as expected under ideal conditions. The second series of tests determined that the matching element is effective for a reasonable range of variations and non-ideal conditions. The third series of tests showed that changing the functional coefficients of the matching technique can help tune the technique to different conditions. The fourth series of tests demonstrated that the basic concept of the implementation technique makes sense. The final series of tests demonstrated that modifying the implementation method is at least somewhat effective and that modifications to it can be used to specifically tailor the implementation to a method. Overall the results indicate that the stated goals of the project were accomplished successfully.
ContributorsFleetwood, Garrett Clark (Author) / Thanga, Jekan (Thesis director) / Berman, Spring (Committee member) / Middleton, James (Committee member) / Economics Program in CLAS (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
In recent years, networked systems have become prevalent in communications, computing, sensing, and many other areas. In a network composed of spatially distributed agents, network-wide synchronization of information about the physical environment and the network configuration must be maintained using measurements collected locally by the agents. Registration is a process

In recent years, networked systems have become prevalent in communications, computing, sensing, and many other areas. In a network composed of spatially distributed agents, network-wide synchronization of information about the physical environment and the network configuration must be maintained using measurements collected locally by the agents. Registration is a process for connecting the coordinate frames of multiple sets of data. This poses numerous challenges, particularly due to availability of direct communication only between neighboring agents in the network. These are exacerbated by uncertainty in the measurements and also by imperfect communication links. This research explored statistically based registration in a sensor network. The approach developed exploits measurements of offsets formed as differences of state values between pairs of agents that share a link in the network graph. It takes into account that the true offsets around any closed cycle in the network graph must sum to zero.
ContributorsPhuong, Shih-Ling (Author) / Cochran, Douglas (Thesis director) / Berman, Spring (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2014-05
Description
The aim of this project was to develop user-friendly methods for programming and controlling a new type of small robot platform, called Pheeno, both individually and as part of a group. Two literature reviews are presented to justify the need for these robots and to discuss what other platforms have

The aim of this project was to develop user-friendly methods for programming and controlling a new type of small robot platform, called Pheeno, both individually and as part of a group. Two literature reviews are presented to justify the need for these robots and to discuss what other platforms have been developed for similar applications. In order to accomplish control of multiple robots work was done on controlling a single robot first. The response of a gripper arm attachment for the robot was smoothed, graphical user interfaces were developed, and commands were sent to a single robot using a video game controller. For command of multiple robots a class was developed in Python to make it simpler to send commands and keep track of different characteristics of each individual robot. A simple script was also created as a proof of concept to show how threading could be used to send different commands simultaneously to multiple robots in order to test algorithms on a group of robots. The class and two other scripts necessary for implementing the class are also presented to make it possible for future use of the given work.
ContributorsHutchins, Gregory Scott (Author) / Berman, Spring (Thesis director) / Artemiadis, Panagiotis (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
Interest in Micro Aerial Vehicle (MAV) research has surged over the past decade. MAVs offer new capabilities for intelligence gathering, reconnaissance, site mapping, communications, search and rescue, etc. This thesis discusses key modeling and control aspects of flapping wing MAVs in hover. A three degree of freedom nonlinear model is

Interest in Micro Aerial Vehicle (MAV) research has surged over the past decade. MAVs offer new capabilities for intelligence gathering, reconnaissance, site mapping, communications, search and rescue, etc. This thesis discusses key modeling and control aspects of flapping wing MAVs in hover. A three degree of freedom nonlinear model is used to describe the flapping wing vehicle. Averaging theory is used to obtain a nonlinear average model. The equilibrium of this model is then analyzed. A linear model is then obtained to describe the vehicle near hover. LQR is used to as the main control system design methodology. It is used, together with a nonlinear parameter optimization algorithm, to design a family multivariable control system for the MAV. Critical performance trade-offs are illuminated. Properties at both the plant output and input are examined. Very specific rules of thumb are given for control system design. The conservatism of the rules are also discussed. Issues addressed include

What should the control system bandwidth be vis--vis the flapping frequency (so that averaging the nonlinear system is valid)?

When is first order averaging sufficient? When is higher order averaging necessary?

When can wing mass be neglected and when does wing mass become critical to model?

This includes how and when the rules given can be tightened; i.e. made less conservative.
ContributorsBiswal, Shiba (Author) / Rodriguez, Armando (Thesis advisor) / Mignolet, Marc (Thesis advisor) / Berman, Spring (Committee member) / Arizona State University (Publisher)
Created2015