Current Search:  Kinematics (x)

View All Items

  • CSV Spreadsheet
(1 - 10 of 10)
The Functional Morphology of Shark Control Surfaces: A Comparative Analysis
Title
The Functional Morphology of Shark Control Surfaces: A Comparative Analysis.
Creator
Hoffmann, Sarah Louise, Porter, Marianne E., Florida Atlantic University, Charles E. Schmidt College of Science, Department of Biological Sciences
Abstract/Description
Sharks are an objectively diverse group of animals; ranging in maximum size from 2,000cm (whale shark) to 17cm (dwarf lantern shark); occupying habitats that are periodically terrestrial (epaulette shark) to the deepest parts of the ocean (frilled shark); relying on a diversity of diets from plankton to marine mammals; with vast amounts of morphology diversity such as the laterally expanded heads of hammerhead species, the elongate caudal fins of thresher species, and the tooth embedded...
Show moreSharks are an objectively diverse group of animals; ranging in maximum size from 2,000cm (whale shark) to 17cm (dwarf lantern shark); occupying habitats that are periodically terrestrial (epaulette shark) to the deepest parts of the ocean (frilled shark); relying on a diversity of diets from plankton to marine mammals; with vast amounts of morphology diversity such as the laterally expanded heads of hammerhead species, the elongate caudal fins of thresher species, and the tooth embedded rostrum of saw shark species representing some of the anatomical extremes. Yet despite these obvious differences in morphology, physiology, and ecology, the challenges associated with studying hard to access, large bodied, pelagic animals have limited our comparative understanding of form and function as it relates to swimming within this group. The majority of shark swimming studies examine species that succeed in captivity, which are usually benthic associated sharks that spend time resting on the substrate. These studies have also been limited by the use of flumes, in which the unidirectional flow and small working area precludes the analysis of larger animals, volitional swimming, and maneuvering. The few existing volitional kinematics studies on sharks quantify two-dimensional kinematics which are unable to capture movements not observable in the plane of reference. With this study, we quantified the volitional swimming kinematics of sharks in relation to morphological, physiological, and ecological variation among species. We developed a technique to analyze three-dimensional (3D) kinematics in a semi-natural, large volume environment, which, to our knowledge, provides the first3D analysis of volitional maneuvering in sharks. We demonstrated that Pacific spiny dogfish and bonnethead sharks rotate the pectoral fins substantially during yaw (horizontal) maneuvering and is correlated with turning performance. We proposed that ecomorphological differences correlate with the varied maneuvering strategies we observed between the two species. We also found that there is some mechanical constraint on shark pectoral fin shape that is explained by phylogenetic relationships but describe a continuum of morphological variables within that range. We propose standardized terminology and methodology for the future assessment of shark pectoral fin morphology and function. As with previous studies, the ease of access to species was a challenge in this study and future studies should continue to assess the functional ecomorphology of shark pectoral fins among species.
Show less
Date Issued
2019
PURL
http://purl.flvc.org/fau/fd/FA00013217
Subject Headings
Sharks, Morphology (Animals), Kinematics
Format
Document (PDF)
NOT SO STRAIGHT FORWARD: SWIMMING, MANEUVERING, AND FEEDING KINEMATICS OF THE SCALLOPED HAMMERHEAD (SPHYRNA LEWINI)
Title
NOT SO STRAIGHT FORWARD: SWIMMING, MANEUVERING, AND FEEDING KINEMATICS OF THE SCALLOPED HAMMERHEAD (SPHYRNA LEWINI).
Creator
Heerdegen, Ivan, Porter, Marianne E., Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
Abstract/Description
Many studies on shark swimming have examined kinematic variables along straight tracks or under controlled flow speeds in flumes, but there is less known about unsteady swimming during maneuvering or feeding. Sharks may adjust their speed, undulatory kinematics, or body curvature to accommodate different actions. This study quantified variations in kinematics during straight swimming, maneuvering, and feeding in scalloped hammerhead sharks (Sphyrna lewini). I obtained video of three juvenile...
Show moreMany studies on shark swimming have examined kinematic variables along straight tracks or under controlled flow speeds in flumes, but there is less known about unsteady swimming during maneuvering or feeding. Sharks may adjust their speed, undulatory kinematics, or body curvature to accommodate different actions. This study quantified variations in kinematics during straight swimming, maneuvering, and feeding in scalloped hammerhead sharks (Sphyrna lewini). I obtained video of three juvenile scalloped hammerheads, developed an ethogram assessing three behavioral categories, and tracked points along the body’s midline. I found that velocity was lower during feeding compared to maneuvering and straight swimming, while body curvature increased during feeding turns but decreased with increasing velocity. These data will provide insight into kinematic variations in hammerhead sharks across ontogeny and among behaviors, ultimately expanding on the relationship between form and function. This also provides context for varying behaviors and trends within the movement ecology paradigm.
Show less
Date Issued
2022
PURL
http://purl.flvc.org/fau/fd/FA00014079
Subject Headings
Kinematics, Hammerhead sharks
Format
Document (PDF)
Selection of manufacturing tolerances for open-chain mechanisms
Title
Selection of manufacturing tolerances for open-chain mechanisms.
Creator
Kumar, Arun., Florida Atlantic University, Masory, Oren, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
Flexible manufacturing systems play an important role in modern industries. The equipment used in flexible manufacturing systems such as industrial robots, NC machines, conveyors etc. demand high performance and accuracies. The selection of manufacturing tolerances is critical in deciding the accuracy of the mechanism and the manufacturing cost. In the present work a new kinematic model for open-chain mechanism is proposed which will help the designer in selecting the manufacturing tolerances...
Show moreFlexible manufacturing systems play an important role in modern industries. The equipment used in flexible manufacturing systems such as industrial robots, NC machines, conveyors etc. demand high performance and accuracies. The selection of manufacturing tolerances is critical in deciding the accuracy of the mechanism and the manufacturing cost. In the present work a new kinematic model for open-chain mechanism is proposed which will help the designer in selecting the manufacturing tolerances. The model allows the designer to estimate the manufacturing cost for the required accuracy. By using the model and the cost function, a set of tolerances can be estimated to achieve the required accuracy and/or manufacturing cost. The end point location and the manufacturing cost of the mechanism are expressed as a functions of tolerances and major dimensions. By using these expressions one can optimize the tolerances based on (1) optimizing accuracy under the cost constraint, (2) optimizing cost under the accuracy constraint.
Show less
Date Issued
1992
PURL
http://purl.flvc.org/fcla/dt/14814
Subject Headings
Tolerance (Engineering), Machinery, Kinematics of
Format
Document (PDF)
Applications of logic programming to manipulator kinematics and problems in controls and signal processing
Title
Applications of logic programming to manipulator kinematics and problems in controls and signal processing.
Creator
Diaz-Robainas, Regino R., Florida Atlantic University, Huang, Ming Z.
Abstract/Description
A PC-based Expert System that uses symbolic manipulations and an inference engine rule-based system to solve direct and inverse kinematics of revolute-jointed manipulators of arbitrary configuration is presented and discussed. Similar applications in the areas of Discrete Signal Processing and Optimal Control are analyzed.
Date Issued
1992
PURL
http://purl.flvc.org/fcla/dt/14794
Subject Headings
Signal processing, Kinematics, Computer-aided design
Format
Document (PDF)
Application of fuzzy logic for the solution of inverse kinematics and hierarchical controls of robotic manipulators
Title
Application of fuzzy logic for the solution of inverse kinematics and hierarchical controls of robotic manipulators.
Creator
Howard, David William., Florida Atlantic University, Zilouchian, Ali
Abstract/Description
In this thesis work, hierarchical control techniques will be used for controlling a robotic manipulator. The hierarchical control will be implemented with fuzzy logic to improve the robustness and reduce the run time computational requirements. Hierarchical control will consist on solving the inverse kinematic equations using fuzzy logic to direct each individual joint. A commercial Micro-robot with three degrees of freedom will be used to evaluate this methodology. A decentralized fuzzy...
Show moreIn this thesis work, hierarchical control techniques will be used for controlling a robotic manipulator. The hierarchical control will be implemented with fuzzy logic to improve the robustness and reduce the run time computational requirements. Hierarchical control will consist on solving the inverse kinematic equations using fuzzy logic to direct each individual joint. A commercial Micro-robot with three degrees of freedom will be used to evaluate this methodology. A decentralized fuzzy controller will be used for each joint, with a Fuzzy Associative Memories (FAM) performing the inverse kinematic mapping in a supervisory mode. The FAM determines the inverse kinematic mapping which maps the desired Cartesian coordinates to the individual joint angles. The individual fuzzy controller for each joint will generate the required control signal to a DC motor to move the associated link to the new position. The proposed hierarchical fuzzy controller will be compared to a conventional PD controller.
Show less
Date Issued
1997
PURL
http://purl.flvc.org/fcla/dt/15407
Subject Headings
Robotics, Fuzzy logic, Robots--Kinematics
Format
Document (PDF)
Kinematic modeling and analysis of a parallel-series hybrid manipulator
Title
Kinematic modeling and analysis of a parallel-series hybrid manipulator.
Creator
Sheng, Yang., Florida Atlantic University, Huang, Ming Z., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
Traditional industrial manipulators possess fixed configuration and are widely used in manufacturing application in which the manipulator base is fixed. However, some applications exist which would require the robotic manipulators to function in non-stationary environment especially in space. In this thesis, a six degree of freedom parallel-series hybrid manipulator is described. It consists of a 3 d.o.f. in-series manipulator mounted on a 3 d.o.f. in-parallel manipulator. A compatibility...
Show moreTraditional industrial manipulators possess fixed configuration and are widely used in manufacturing application in which the manipulator base is fixed. However, some applications exist which would require the robotic manipulators to function in non-stationary environment especially in space. In this thesis, a six degree of freedom parallel-series hybrid manipulator is described. It consists of a 3 d.o.f. in-series manipulator mounted on a 3 d.o.f. in-parallel manipulator. A compatibility equation is found to govern the relationship between in-series component angular velocity and linear velocity; a constraint equation is added to the Jacobian of in-parallel component. Using these two equations, a decomposition strategy is proposed for solving the inverse velocity problem of the hybrid manipulator together with the simulation examples of inverse position tracking and straight line trajectory planning. Effectiveness of this method and factors affecting the simulation result are examined.
Show less
Date Issued
1993
PURL
http://purl.flvc.org/fcla/dt/14893
Subject Headings
Kinematics, Robotics--Computer programs, Manipulators (Mechanism)
Format
Document (PDF)
unified theory of coordination for robotic mechanisms with general parallel or hybrid structures
Title
A unified theory of coordination for robotic mechanisms with general parallel or hybrid structures.
Creator
Ling, Shou-Hung., Florida Atlantic University, Huang, Ming Z., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
A well designed robot manipulator should have adequate workspace and good static-dynamic performance. It is well known that serial manipulators, while compared to similar size parallel ones, have larger workspace. However, due to their cantilever-like structure, the serial manipulators suffer from the disadvantage of having relatively poor static-dynamic performance. Contrarily, for fully parallel manipulators the good static-dynamic performance comes from the sacrifice of the workspace....
Show moreA well designed robot manipulator should have adequate workspace and good static-dynamic performance. It is well known that serial manipulators, while compared to similar size parallel ones, have larger workspace. However, due to their cantilever-like structure, the serial manipulators suffer from the disadvantage of having relatively poor static-dynamic performance. Contrarily, for fully parallel manipulators the good static-dynamic performance comes from the sacrifice of the workspace. Therefore, manipulators with more general geometries, in particular those with both the serial and the parallel modules, namely the hybrid manipulators, have attracted much of the research attention in robotics recently. While it can be asserted that kinematic theories and techniques are well established for fully serial-chain manipulators, the same assertion cannot be made when they are considered in the above general context. The research described in this dissertation is an undertaking toward the establishment of a general theory of coordination for robotic mechanisms with general parallel or hybrid structures. The scope of this research is concentrated in the kinematics aspect of the aforementioned class of robot manipulators with the main emphasis on the velocity (instantaneous) kinematics. A kinestatic approach, which is based on screw system theory, is adopted in this dissertation. This kinestatic approach leads to the establishment of a fundamental theorem, dubbed as the Parallel Manipulator Coordination Theorem, which integrates the idea of parallel and serial manipulators. Furthermore, the theorem enables us to develop an analysis strategy for systematic formulation and characterization of robotic mechanisms with general parallel (non-redundant) and hybrid geometries. The analysis strategy entails constraints, statics, velocity, and singularity considerations. One distinct advantage of using the screw system theory as the analysis tool is that it facilitates the analysis in a fashion that physical meanings are preserved through out the derivation. The very aspect of preserving the physical meaning distinguishes this method from other algebraically-based and numerically-based methods. An intelligent fault-tolerant system has been studied at the end. The technique and conclusions from the study of parallel manipulator modules have been used to analyze the proposed design.
Show less
Date Issued
1994
PURL
http://purl.flvc.org/fcla/dt/12385
Subject Headings
Manipulators (Mechanism), Robotics, Kinematics, Screws, Theory of
Format
Document (PDF)
Analyzing the effect of fin morphology on the propulsive performance of an oscillating caudal fin using a robotic model
Title
Analyzing the effect of fin morphology on the propulsive performance of an oscillating caudal fin using a robotic model.
Creator
Fischer, Tyler M., Curet, Oscar M., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
A bio-inspired robotic underwater vessel was developed to test the effect of fin morphology on the propulsive performance of caudal fin. The robotic vessel, called The Bullet Fish, features a cylindrical body with a hemisphere at the forward section and a conical body at the stern. The vessel uses an oscillating caudal fin for thrust generation. The robotic vessel was tested in a recirculating flume for seven different caudal fins that range different bio-inspired forms and aspect ratios. The...
Show moreA bio-inspired robotic underwater vessel was developed to test the effect of fin morphology on the propulsive performance of caudal fin. The robotic vessel, called The Bullet Fish, features a cylindrical body with a hemisphere at the forward section and a conical body at the stern. The vessel uses an oscillating caudal fin for thrust generation. The robotic vessel was tested in a recirculating flume for seven different caudal fins that range different bio-inspired forms and aspect ratios. The experiments were performed at four different flow velocities and two flapping frequencies: 0.5 and 1.0 Hz. We found that for 1 Hz flapping frequency that in general as the aspect-ratio decreases both thrust production tends and power decrease resulting in a better propulsive efficiency for aspect ratios between 0.9 and 1.0. A less uniform trend was found for 0.5 Hz, where our data suggest multiple efficiency peaks. Additional experiments on the robotic model could help understand the propulsion aquatic locomotion and help the design of bio-inspired underwater vehicles.
Show less
Date Issued
2017
PURL
http://purl.flvc.org/fau/fd/FA00004944, http://purl.flvc.org/fau/fd/FA00004944
Subject Headings
Robotics., Robots--Kinematics., Artificial intelligence., Biomimetics., Bioinformatics., Stereotypes (Social psychology)
Format
Document (PDF)
Development of a Flapping Actuator Based on Oscillating Electromagnetic Fields
Title
Development of a Flapping Actuator Based on Oscillating Electromagnetic Fields.
Creator
Spragg, Donald Oakley, Curet, Oscar M., Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description
In this work a bio-inspired flapping actuator based on varied magnetic fields is developed, controlled and characterized. The actuator is sought to contribute to the toolbox of options for bio-mimetics research. The design is that of a neodymium bar magnet on one end of an armature which is moved by two air core electromagnetic coils in the same manner as agonist and antagonist muscle pairs function in biological systems. The other end of the armature is fitted to a rigid fin extending beyond...
Show moreIn this work a bio-inspired flapping actuator based on varied magnetic fields is developed, controlled and characterized. The actuator is sought to contribute to the toolbox of options for bio-mimetics research. The design is that of a neodymium bar magnet on one end of an armature which is moved by two air core electromagnetic coils in the same manner as agonist and antagonist muscle pairs function in biological systems. The other end of the armature is fitted to a rigid fin extending beyond the streamline enclosure body to produce propulsion. A series of tests in still water were performed to measure the kinematics and propulsive force for different control schemes including the effect of adding antagonistic resistance to the control schemes. Control methods based on armature position and based on setpoint error were tested and antagonist force was found to increase consistency of control of the systems in certain cases.
Show less
Date Issued
2016
PURL
http://purl.flvc.org/fau/fd/FA00004699, http://purl.flvc.org/fau/fd/FA00004699
Subject Headings
Actuators -- Materials, Artificial intelligence -- Biological applications, Biomimetics, Biophysics, Natural computation, Robotics, Robots -- Kinematics
Format
Document (PDF)
Self-calibration of laser tracking measurement system with planar constraints
Title
Self-calibration of laser tracking measurement system with planar constraints.
Creator
Motaghedi, Shui Hu., Florida Atlantic University, Zhuang, Hanqi, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description
Laser tracking coordinate measuring machines have the potential of continuously measuring three dimensional target coordinates in a large workspace with a fast sampling rate and high accuracy. Proper calibration of a laser tracking measurement system is essential prior to use of such a device for metrology. In the absence of a more accurate instrument for system calibration, one has to rely on self-calibration strategies. In this dissertation, a kinematic model that describes not only the...
Show moreLaser tracking coordinate measuring machines have the potential of continuously measuring three dimensional target coordinates in a large workspace with a fast sampling rate and high accuracy. Proper calibration of a laser tracking measurement system is essential prior to use of such a device for metrology. In the absence of a more accurate instrument for system calibration, one has to rely on self-calibration strategies. In this dissertation, a kinematic model that describes not only the motion but also geometric variations of a multiple-beam laser tracking system was developed. The proposed model has the following features: (1) Target positions can be computed from both distance and angular measurements. (2) Through error analysis it was proven that even rough angular measurement may improve the overall system calibration results. A self-calibration method was proposed to calibrate intelligent machines with planar constraints. The method is also applied to the self-calibration of the laser tracking system and a standard PUMA 560 robot. Various calibration strategies utilizing planar constraints were explored to deal with different system setups. For each calibration strategy, issues about the error parameter estimation of the system were investigated to find out under which conditions these parameters can be uniquely estimated. These conditions revealed the applicability of the planar constraints to the system self-calibration. The observability conditions can serve as a guideline for the experimental setup when planar constraint is utilized in the machine calibration including the calibration of the laser tracking systems. Intensive simulation studies were conducted to check validity of the theoretical results. Realistic noise values were injected to the system models to statistically assess the behavior of the self-calibration system under real-world conditions. Various practical calibration issues were also explored in the simulations and therefore to pave ways for experimental investigation. The calibration strategies were also applied experimentally to calibrate a laser tracking system constructed at the Robotics Center in Florida Atlantic University.
Show less
Date Issued
1999
PURL
http://purl.flvc.org/fcla/dt/12599
Subject Headings
Robots--Kinematics, Robotics--Calibration--Measurement, Robots--Control systems
Format
Document (PDF)