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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.
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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.
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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.
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Date Issued
1994
PURL
http://purl.flvc.org/fcla/dt/12385
Subject Headings
Manipulators (Mechanism), Robotics, Kinematics, Screws, Theory of
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.
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Date Issued
1999
PURL
http://purl.flvc.org/fcla/dt/12599
Subject Headings
Robots--Kinematics, Robotics--Calibration--Measurement, Robots--Control systems
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.
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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.
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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)