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Articles 1021 - 1050 of 1248
Full-Text Articles in Computer Engineering
Getting It Right The First Time: Robot Mission Guarantees In The Presence Of Uncertainty, Damian Lyons, Ron Arkin, Paramesh Nirmal, Shu Jiang, Tsung-Ming Liu, Julia Deeb
Getting It Right The First Time: Robot Mission Guarantees In The Presence Of Uncertainty, Damian Lyons, Ron Arkin, Paramesh Nirmal, Shu Jiang, Tsung-Ming Liu, Julia Deeb
Faculty Publications
Abstract—Certain robot missions need to perform predictably in a physical environment that may only be poorly characterized in advance. We have previously developed an approach to establishing performance guarantees for behavior-based controllers in a process-algebra framework. We extend that work here to include random variables, and we show how our prior results can be used to generate a Dynamic Bayesian Network for the coupled system of program and environment model. Verification is reduced to a filtering problem for this network. Finally, we present validation results that demonstrate the effectiveness of the verification of a multiple waypoint robot mission using this …
Dexterous Hexrotor Uav Platform, Guangying Jiang
Dexterous Hexrotor Uav Platform, Guangying Jiang
Electronic Theses and Dissertations
Mobile manipulation is a hot area of study in robotics as it unites the two classes of robots: locomotors and manipulators. An emerging niche in the field of mobile manipulation is aerial mobile manipulation. Although there has been a fair amount of study of free-flying satellites with graspers, the more recent trend has been to outfit UAVs with graspers to assist various manipulation tasks. While this recent work has yielded impressive results, it is hampered by a lack of appropriate testbeds for aerial mobile manipulation, similar to the state of ground-based mobile manipulation a decade ago. Typical helicopters or quadrotors …
Development Of Pneumatic Robot For Outreach, Eshamogbo E. Ojuba, John Lumkes
Development Of Pneumatic Robot For Outreach, Eshamogbo E. Ojuba, John Lumkes
The Summer Undergraduate Research Fellowship (SURF) Symposium
To encourage the current generation of high school and middle school students to pursue careers in engineering, it is important to have challenging hands-on engineering activities for them. Such activities should be interesting, compelling, and, most importantly, educative. A mini-excavator was built for fluid power outreach, but this tool only demonstrates fluid power, without showing other important aspects of engineering. The tool being developed is able to demonstrate fluid power, as well as other important aspects of engineering, such as controls, electronics, and programming. This tool is an electronically-controlled device that allows the user control a pneumatic circuit, coupled with …
Performance Guarantees For C-Wmd Robot Missions, Shu Jiang, Ronald C. Arkin, Damian M. Lyons, Tsung-Ming Liu, Dagon Harrington
Performance Guarantees For C-Wmd Robot Missions, Shu Jiang, Ronald C. Arkin, Damian M. Lyons, Tsung-Ming Liu, Dagon Harrington
Faculty Publications
Robotics has been considered as one of the five key technology areas for defense against attacks with weapons of mass destruction (WMD). However, due to the mass impact nature of WMD, failures of counter-WMD (C-WMD) missions can have catastrophic consequences.To ensure robot's success in carrying out C-WMD missions, we have developed a novel verification framework in providing performance guarantees for behavior-based and probabilistic robot algorithms in complex real-world environments. This paper describes the system architecture and discusses how the verification framework can be used to provide pre-mission performance guarantees for robots in executing C-WMD missions.
Reasoning Across Language And Vision In Machines And Humans, Andrei Barbu
Reasoning Across Language And Vision In Machines And Humans, Andrei Barbu
Open Access Dissertations
Humans not only outperform AI and computer-vision systems, but use an unknown computational mechanism to perform tasks for which no suitable approaches exist. I present work investigating both novel tasks and how humans approach them in the context of computer vision and linguistics. I demonstrate a system which, like children, acquires high-level linguistic knowledge about the world. Robots learn to play physically-instantiated board games and use that knowledge to engage in physical play. To further integrate language and vision I develop an approach which produces rich sentential descriptions of events depicted in videos. I then show how to simultaneously detect …
Hypothesize-And-Verify Based Solutions For Place Recognition And Mobile Robot Self-Localization In Interior Hallways, Khalil Mustafa Ahmad Yousef
Hypothesize-And-Verify Based Solutions For Place Recognition And Mobile Robot Self-Localization In Interior Hallways, Khalil Mustafa Ahmad Yousef
Open Access Dissertations
There is much research interest currently in having mobile robots build accurate and visually dense models ofinterior space as they traverse through such spaces. One of the interesting problems that has came out of this research is that of visual place recognition and self-localization. This is the problem that forms the focus of the present dissertation. We show how dense and accurate 3D models of the interior space can be constructed using a hierarchical sensor-fusion architecture. Our system fuses images from a single photometric camera with range data from a laser scanning sensor. The range data used is rudimentary--the range …
Continuum Robotic Surface: Forward Kinematic Analysis And Implementation, Jessica Merino
Continuum Robotic Surface: Forward Kinematic Analysis And Implementation, Jessica Merino
All Theses
This thesis presents a new class of biologically inspired robots: continuum robotic surfaces. This work is fueled by the question: can the interaction between robot and environment be advanced with “programmable surfaces in space?” The novelty of continuum robotic surfaces lies in their ability to be actively controlled and reconfigured in what we believe is the current “missing dimension” in robot movements — two–dimensional space. We believe that such surfaces will lend themselves to more complex applications. However, to effectively deploy such surfaces for these complex applications, kinematic models will be necessary to plan and control desired configurations. The forward …
Modeling, Control, And Motion Analysis Of A Class Of Extensible Continuum Manipulators, Apoorva Kapadia
Modeling, Control, And Motion Analysis Of A Class Of Extensible Continuum Manipulators, Apoorva Kapadia
All Dissertations
In this dissertation, the development of a kinematic model, a configuration-space controller, a master-slave teleoperation controller, along with the analysis of the self-motion properties for redundant, extensible, continuous backbone (continuum) ``trunk and tentacle' manipulators are detailed. Unlike conventional rigid-link robots, continuum manipulators are robots that can bend at any point along their backbone, resulting in new and unique modeling and control issues. Taken together, these chapters represent one of the first efforts towards devising model-based controllers of such robots, as well as characterizing their self-motion in its simplest form.
Chapter 2 describes the development of a convenient set of generalized, …
Mobile Robot Navigation For Person Following In Indoor Environments, Ninad Pradhan
Mobile Robot Navigation For Person Following In Indoor Environments, Ninad Pradhan
All Dissertations
Service robotics is a rapidly growing area of interest in robotics research. Service robots inhabit human-populated environments and carry out specific tasks. The goal of this dissertation is to develop a service robot capable of following a human leader around populated indoor environments. A classification system for person followers is proposed such that it clearly defines the expected interaction between the leader and the robotic follower. In populated environments, the robot needs to be able to detect and identify its leader and track the leader through occlusions, a common characteristic of populated spaces. An appearance-based person descriptor, which augments the …
Decentralized Collision Avoidance, Jayasri K. Janardanan
Decentralized Collision Avoidance, Jayasri K. Janardanan
School of Computing: Dissertations, Theses, and Student Research
Autonomous Robots must carry out their tasks as independently as possible and each robot may be assigned different tasks at different locations. As these tasks are being performed, the robots have to navigate correctly such that the assigned tasks are completed efficiently, while also avoiding each other and other obstacles. To accomplish effective navigation, we must ensure that the robots are calibrated to avoid colliding with any kind of object on its path. Each robot has to sense the obstacles on its path and take necessary corrective measure to avoid those obstacles. In a situation with multiple robots, robots may …
Verifying Performance For Autonomous Robot Missions With Uncertainty, Damian M. Lyons, Ronald Arkin, Tsung-Ming Liu, Shu Jiang, Paramesh Nirmal
Verifying Performance For Autonomous Robot Missions With Uncertainty, Damian M. Lyons, Ronald Arkin, Tsung-Ming Liu, Shu Jiang, Paramesh Nirmal
Faculty Publications
Establishing performance guarantees for robot missions is especially important for C-WMD applications. Software verification techniques, such as model checking (Clark 1999, Jhala & Majumdar 2009), can be applied to robotic applications but characteristics of this application area, including addition of a robot environment model and handling continuous spatial location well, exacerbate state explosion, a key weakness of these methods. We have proposed an approach to verifying robot missions that shifts the focus from state-based analysis onto the solution of a set of flow equations (Lyons et al. 2012). The key novelty introduced in this paper is a probabilistic spatial representation …
Bruno The Robotic Bear, Aaron Brauner, Ian Panzer
Bruno The Robotic Bear, Aaron Brauner, Ian Panzer
Computer Engineering
Creating homemade robots are becoming a popular hobby among engineers. With the dramatic reduction in costs over the past few decades, it is finally possible to build a personal automated mailbox. Microcontrollers needed to function as the brains of the robot are also becoming powerful enough that relatively complicated instructions could be programmed into the robot to handle a plethora of sensors and peripherals. In order to demonstrate how the Computer Engineering department models the synthesis of computer science and electrical engineering, the topic chosen was robotics, specifically, a stuffed bear robot.
The microcontroller chosen was the Arduino Mega 2560 …
Flarebot - Analysis Of An Autonomous Robot, Sanat S. Sahasrabudhe
Flarebot - Analysis Of An Autonomous Robot, Sanat S. Sahasrabudhe
Computer Engineering
Autonomous robots are increasing in popularity for educational, research, and household purposes. This report analyzes the design and functionality of one such example, called FlareBot, which is designed to self-navigate and stack cans. Specifically, the robot is designed to follow a fixed path for navigation, and stack any cans it comes across. Once a maximum number of cans is stacked, the robot releases them and restarts the process. The design is achieved using three DC motors, two servo motors, one line sensor, and one infrared sensor. Designing autonomous robots is a strong test of the engineering design process, which includes …
Automatic Site Reconstruction With A Mobile Robot And Scanning Laser Proximity Sensor, Erik Nelson, Sean Willis, Nathan Lucero
Automatic Site Reconstruction With A Mobile Robot And Scanning Laser Proximity Sensor, Erik Nelson, Sean Willis, Nathan Lucero
Computer Engineering
Leading research in robotics, especially in the areas of computer vision, planning, and probabilistic learning, require a mobile robot platform to program. The design and construction of such a platform is a laborious task, calling upon knowledge from many branches of engineering. Additionally, hot research topics in robotics such as vision-based Simultaneous Localization and Mapping (SLAM), advanced trajectory planning algorithms, and adaptive control for collision avoidance contain algorithms that build upon a localization and mapping architecture which is time-consuming to program in itself. To bring future senior project teams from Cal Poly's computer engineering and computer science departments closer to …
Modeling A Sensor To Improve Its Efficacy, Nabin K. Malakar, Daniil Gladkov, Kevin H. Knuth
Modeling A Sensor To Improve Its Efficacy, Nabin K. Malakar, Daniil Gladkov, Kevin H. Knuth
Physics Faculty Scholarship
Robots rely on sensors to provide them with information about their surroundings. However, high-quality sensors can be extremely expensive and cost-prohibitive. Thus many robotic systems must make due with lower-quality sensors. Here we demonstrate via a case study how modeling a sensor can improve its efficacy when employed within a Bayesian inferential framework. As a test bed we employ a robotic arm that is designed to autonomously take its own measurements using an inexpensive LEGO light sensor to estimate the position and radius of a white circle on a black field. The light sensor integrates the light arriving from a …
Performance Verification For Behavior-Based Robot Missions, Damian M. Lyons, Ronald Arkin, Shu Jiang, Tsung-Ming Liu, Paramesh Nirmal, J. Deeb
Performance Verification For Behavior-Based Robot Missions, Damian M. Lyons, Ronald Arkin, Shu Jiang, Tsung-Ming Liu, Paramesh Nirmal, J. Deeb
Faculty Publications
Certain robot missions need to perform predictably in a physical en-vironment that may only be poorly characterized in advance. This requirement raises many issues for existing approaches to software verification. An approach based on behavior-based controllers in a process-algebra framework is proposed by Lyons et al [15] to side-step state combinatorics. In this paper we show that this approach can be used to generate a Dynamic Bayesian Network for the problem, and that verification is reduced to a filtering problem for this network. We present validation results for the verification of a multiple waypoint robot mission using this approach.
Robotic Kinect Bear, Spencer Lines, Dennis Waldron, Sagiv Sheelo
Robotic Kinect Bear, Spencer Lines, Dennis Waldron, Sagiv Sheelo
Computer Engineering
The goal of this project was to create an interactive 53”-tall robotic teddy bear to showcase various aspects of Cal Poly’s computer engineering degree. The interactive element took the form of a Microsoft Kinect for Windows sensor, which provided body and face position tracking of the user. Using this sensor and various other elements, we successfully made a teddy bear which mirrors a user's face and arm positions in real-time.
An Analysis Of Simultaneous Localization And Mapping (Slam) Algorithms, Megan R. Naminski
An Analysis Of Simultaneous Localization And Mapping (Slam) Algorithms, Megan R. Naminski
Mathematics, Statistics, and Computer Science Honors Projects
This paper provides an introduction to two Simultaneous Localization and Mapping (SLAM) algorithms: EKF SLAM and Fast-SLAM. SLAM allows an autonomous robot to accurately map an unknown environment as well as locate itself within the environment. These algorithms work iteratively, by moving about the environment and extracting and observing various landmarks in the environment. EKF SLAM and Fast-SLAM solve the SLAM problem by using probabilities to control for errors in the robot's sensors. This paper provides a discussion of these two algorithms and compares their run times and the accuracy of the maps they produce.
Fusion Of Ranging Data From Robot Teams Operating In Confined Areas, Damian M. Lyons, Karma Shrestha, Tsung-Ming Liu
Fusion Of Ranging Data From Robot Teams Operating In Confined Areas, Damian M. Lyons, Karma Shrestha, Tsung-Ming Liu
Faculty Publications
We address the problem of fusing laser ranging data from multiple mobile robots that are surveying an area as part of a robot search and rescue or area surveillance mission. We are specifically interested in the case where members of the robot team are working in close proximity to each other. The advantage of this teamwork is that it greatly speeds up the surveying process; the area can be quickly covered even when the robots use a random motion exploration approach. However, the disadvantage of the close proximity is that it is possible, and even likely, that the laser ranging …
A Cognitive Approach To Vision For A Mobile Robot, Paul Benjamin, Christopher Funk, Damian M. Lyons
A Cognitive Approach To Vision For A Mobile Robot, Paul Benjamin, Christopher Funk, Damian M. Lyons
Faculty Publications
We describe a cognitive vision system for a mobile robot. This system works in a manner similar to the human vision system, using saccadic, vergence and pursuit movements to extract information from visual input. At each fixation, the system builds a 3D model of a small region, combining information about distance, shape, texture and motion. These 3D models are embedded within an overall 3D model of the robot's environment. This approach turns the computer vision problem into a search problem, with the goal of constructing a physically realistic model of the entire environment. At each step, the vision system selects …
Cpe 200: Small Bear Project, David Burke, Devin Tang
Cpe 200: Small Bear Project, David Burke, Devin Tang
Computer Engineering
CPE 200 is an elective course designed for sophomores in the Computer Engineering Department. This project was intended to design the class, such that, students will understand the skills a computer engineer develops and how to apply those skills.
A Software Tool For The Design Of Critical Robot Missions With Performance Guarantees, Damian M. Lyons, Ronald C. Arkin, Paramesh Nirmal, Shu Jiang, Tsung-Ming Liu
A Software Tool For The Design Of Critical Robot Missions With Performance Guarantees, Damian M. Lyons, Ronald C. Arkin, Paramesh Nirmal, Shu Jiang, Tsung-Ming Liu
Faculty Publications
Deploying a robot as part of a counter-weapons of mass destruction mission demands that the robotic software operates with high assurance. A unique feature of robotic software development is the need to perform predictably in a physical environment that may only be poorly characterized in advance. In this paper, we present an approach to building high assurance software for robot missions carried out in uncertain environments. The software development framework and the verification algorithm, VIPARS, are described in detail. Results are presented for missions including motion and sensing uncertainty, interaction with obstacles, and the use of sensors to guide behavior.
Caddy: A 2005 Roborodentia Entry With Vision And Path Planning Abilities, Taylor Braun-Jones
Caddy: A 2005 Roborodentia Entry With Vision And Path Planning Abilities, Taylor Braun-Jones
Computer Engineering
Roborodentia is an autonomous robotics competition held each year during Cal Poly’s Open House. For the 2005 competition, robot entries needed to navigate a maze searching for three randomly placed golf balls, collect them, and then deposit the balls in the “nest” at the end of the maze. A newly added aspect for the 2005 competition included two bonus balls that were placed on a platform behind the wall in two predetermined corners of the maze.
Caddy is a robot that was entered into the 2005 Roborodentia competition. Caddy included a vision system that allowed searching for balls down untraveled …
Visual Homing With A Pan-Tilt Based Stereo Camera, Paramesh Nirmal, Damian M. Lyons
Visual Homing With A Pan-Tilt Based Stereo Camera, Paramesh Nirmal, Damian M. Lyons
Faculty Publications
Visual homing is a navigation method based on comparing a stored image of the goal location and the current image (current view) to determine how to navigate to the goal location. It is theorized that insects, such as ants and bees, employ visual homing methods to return to their nest [1]. Visual homing has been applied to autonomous robot platforms using two main approaches: holistic and feature-based. Both methods aim at determining distance and direction to the goal location. Navigational algorithms using Scale Invariant Feature Transforms (SIFT) have gained great popularity in the recent years due to the robustness of …
Radar Based Collision Avoidance For Unmanned Aircraft Systems, Allistair A. Moses
Radar Based Collision Avoidance For Unmanned Aircraft Systems, Allistair A. Moses
Electronic Theses and Dissertations
Unmanned Aircraft Systems (UAS) have become increasingly prevalent and will represent an increasing percentage of all aviation. These unmanned aircraft are available in a wide range of sizes and capabilities and can be used for a multitude of civilian and military applications. However, as the number of UAS increases so does the risk of mid-air collisions involving unmanned aircraft. This dissertation aims present one possible solution for addressing the mid-air collision problem in addition to increasing the levels of autonomy of UAS beyond waypoint navigation to include preemptive sensor-based collision avoidance. The presented research goes beyond the current state of …
Reducing Communication Delay Variability For A Group Of Robots, Goncalo Martins
Reducing Communication Delay Variability For A Group Of Robots, Goncalo Martins
Electronic Theses and Dissertations
A novel architecture is presented for reducing communication delay variability for a group of robots. This architecture relies on using three components: a microprocessor architecture that allows deterministic real-time tasks; an event-based communication protocol in which nodes transmit in a TDMA fashion, without the need of global clock synchronization techniques; and a novel communication scheme that enables deterministic communications by allowing senders to transmit without regard for the state of the medium or coordination with other senders, and receivers can tease apart messages sent simultaneously with a high probability of success. This approach compared to others, allows simultaneous communications without …
Robot Team Formation Control Using Communication "Throughput Approach", Fatmazahra Ahmed Benhalim
Robot Team Formation Control Using Communication "Throughput Approach", Fatmazahra Ahmed Benhalim
Electronic Theses and Dissertations
In this thesis, we consider a team of robots forming a mobile robot network cooperating to accomplish a mission in an unknown but structured environment. The team has no a-priori knowledge of the environment. Robots have limited memory storage capabilities, not enough to map the environment. Each robot also has limited sensor capability and computational power. Due to the need to avoid obstacles and other environment effects, some robots get delayed from the rest. Using tracking controller, the robot team should follow the leader in a flexible formation shape without losing network connectivity, and that was achieved by monitoring the …
Navigation & Control Of An Automated Swath Surface Vessel For Bathymetric Mapping, Ketan Rasal
Navigation & Control Of An Automated Swath Surface Vessel For Bathymetric Mapping, Ketan Rasal
Mechanical Engineering Master's Theses
With the abundant amount of water on the earth, the study of underwater terrain plays an important role in the use and sustainability of marine resources. A wide variety of technical systems are used to collect such bathymetric data, and autonomous vehicles are being explored as a manner in which to make this process more cost-effective. Students in Santa Clara University's Robotic Systems Laboratory are contributing to this effort through the development of an autonomous SWATH boat that can create such maps. As part of this thesis work, the navigation and control system of this SWATH boat has been significantly …
Investigation On The Mobile Robot Navigation In An Unknown Environment, Ahmed S. Khusheef
Investigation On The Mobile Robot Navigation In An Unknown Environment, Ahmed S. Khusheef
Theses: Doctorates and Masters
Mobile robots could be used to search, find, and relocate objects in many types of manufacturing operations and environments. In this scenario, the target objects might reside with equal probability at any location in the environment and, therefore, the robot must navigate and search the whole area autonomously, and be equipped with specific sensors to detect objects. Novel challenges exist in developing a control system, which helps a mobile robot achieve such tasks, including constructing enhanced systems for navigation, and vision-based object recognition. The latter is important for undertaking the exploration task that requires an optimal object recognition technique.
In …
A Distributed Local-Leg Feedback Algorithm For Robust Walking On Uneven Terrain, Mayur Ramakant Palankar
A Distributed Local-Leg Feedback Algorithm For Robust Walking On Uneven Terrain, Mayur Ramakant Palankar
USF Tampa Graduate Theses and Dissertations
Legged animals can traverse significantly more of the Earth's land mass than man-made wheeled and tracked vehicles~\cite{Anonymous67}. Their impressive mobility is largely due to multiple dexterous legs and the robust algorithms that coordinate and control them. A legged animal such as a squirrel can exhibit multiple locomotion modes such as walking, running and jumping and also multiple gaits or leg phase timings within each mode. A robot that could mimic this level of robust locomotion would be highly useful for planetary exploration, military reconnaissance, and time-critical search and rescue in cluttered or collapsed buildings.
A number of biological studies on …