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Title: NEIGHBORING NEAR MINIMUM-TIME CONTROLS WITH DISCONTINUITIES AND THE APPLICATION TO THE CONTROL OF MANIPULATORS (PATH-PLANNING, TRACKING, FEEDBACK).
Creator: Zhuang, Hanqi, Florida Atlantic University, Hamano, Fumio, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: This thesis presents several algorithms to treat the problem of closed-loop near minimum-time controls with discontinuities. First, a neighboring control algorithm is developed to solve the problem in which controls are bounded by constant constraints. Secondly, the scheme is extended to account for state-dependent control constraints. And finally, a path tracking algorithm for robotic manipulators is presented, which is also a neighboring control algorithm. These algorithms are suitable for...
Show moreThis thesis presents several algorithms to treat the problem of closed-loop near minimum-time controls with discontinuities. First, a neighboring control algorithm is developed to solve the problem in which controls are bounded by constant constraints. Secondly, the scheme is extended to account for state-dependent control constraints. And finally, a path tracking algorithm for robotic manipulators is presented, which is also a neighboring control algorithm. These algorithms are suitable for real time controls because the on-line computations involved are relatively simple. Simulation results show that these algorithms work well despite the fact that the prescribed final points can not be reached exactly.
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Date Issued: 1986
PURL: http://purl.flvc.org/fcla/dt/14326
Subject Headings: Manipulators (Mechanism), Control theory, Algorithms
Format: Document (PDF)

Title: Two-dimensional approximation and learning control of robot manipulators.
Creator: Gautam, Ashutosh., Florida Atlantic University, Zilouchian, Ali
Abstract/Description: In this thesis, a novel two-dimensional learning control scheme for robot manipulators is proposed. The convergence of the scheme for a general n-degree of freedom robot is shown. In the next part of the thesis, an algorithm for the approximation of a two-dimensional causal, recursive, separable-in-denominator (CRSD) filter, using the impulse response and autocorrelation data, is presented. The stability of the designed filter is discussed and it is shown that the approximated filter is...
Show moreIn this thesis, a novel two-dimensional learning control scheme for robot manipulators is proposed. The convergence of the scheme for a general n-degree of freedom robot is shown. In the next part of the thesis, an algorithm for the approximation of a two-dimensional causal, recursive, separable-in-denominator (CRSD) filter, using the impulse response and autocorrelation data, is presented. The stability of the designed filter is discussed and it is shown that the approximated filter is always stable. The simulation results for the approximation technique as well as the two-dimensional learning control scheme are also included in the thesis.
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Date Issued: 1989
PURL: http://purl.flvc.org/fcla/dt/14559
Subject Headings: Control theory, Manipulators (Mechanism), Robots
Format: Document (PDF)

Title: Derivation and identification of linearly parametrized robot manipulator dynamic models.
Creator: Xu, Hua., Florida Atlantic University, Roth, Zvi S., Zilouchian, Ali, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: The dissertation focuses on robot manipulator dynamic modeling, and inertial and kinematic parameters identification problem. An automatic dynamic parameters derivation symbolic algorithm is presented. This algorithm provides the linearly independent dynamic parameters set. It is shown that all the dynamic parameters are identifiable when the trajectory is persistently exciting. The parameters set satisfies the necessary condition of finding a persistently exciting trajectory. Since in...
Show moreThe dissertation focuses on robot manipulator dynamic modeling, and inertial and kinematic parameters identification problem. An automatic dynamic parameters derivation symbolic algorithm is presented. This algorithm provides the linearly independent dynamic parameters set. It is shown that all the dynamic parameters are identifiable when the trajectory is persistently exciting. The parameters set satisfies the necessary condition of finding a persistently exciting trajectory. Since in practice the system data matrix is corrupted with noise, conventional estimation methods do not converge to the true values. An error bound is given for Kalman filters. Total least squares method is introduced to obtain unbiased estimates. Simulations studies are presented for five particular identification methods. The simulations are performed under different noise levels. Observability problems for the inertial and kinematic parameters are investigated. U%wer certain conditions all L%wearly Independent Parameters derived from are observable. The inertial and kinematic parameters can be categorized into three parts according to their influences on the system dynamics. The dissertation gives an algorithm to classify these parameters.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/12291
Subject Headings: Algorithms, Manipulators (Mechanism), Robots--Control systems
Format: Document (PDF)

Title: Development of a controller for a Stewart platform.
Creator: Marquis, Lawrence Paul., Florida Atlantic University, Masory, Oren, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A Stewart platform is a six degree of freedom robot manipulator with its six links arranged in a parallel configuration. A dynamic model for the plant of each link, which consists of an amplifier, an electrohydraulic servo valve, and a hydraulic actuator, is found from open-loop step and frequency responses. To determine a model for the complete closed loop system, integrators located in the link input and feedback paths were added to the plant's model. PID controllers were designed to...
Show moreA Stewart platform is a six degree of freedom robot manipulator with its six links arranged in a parallel configuration. A dynamic model for the plant of each link, which consists of an amplifier, an electrohydraulic servo valve, and a hydraulic actuator, is found from open-loop step and frequency responses. To determine a model for the complete closed loop system, integrators located in the link input and feedback paths were added to the plant's model. PID controllers were designed to increase the system's bandwidth. Once control of the individual links was achieved, control algorithms were developed to control the motion of Stewart platform. The algorithm would move the platform through its initialization sequence, then control platform velocity, as dictated by the user.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14849
Subject Headings: Manipulators (Mechanism), Robots--Control systems
Format: Document (PDF)

Title: Trajectory control of a new class of CNC machine tools.
Creator: Xiu, Daoxi., Florida Atlantic University, Masory, Oren, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: One emerging application of parallel manipulators is to use them as CNC (Computerized Numerical Controlled) machine tools and recently several prototypes of such CNC machines have been developed, all based on hexapod machine--a type of parallel manipulators similar to a Stewart platform. The goal of this research is to develop an effective control scheme, cross-coupling control, for this type of CNC machine tools, which will reduce the contouring errors and thus further enhance their...
Show moreOne emerging application of parallel manipulators is to use them as CNC (Computerized Numerical Controlled) machine tools and recently several prototypes of such CNC machines have been developed, all based on hexapod machine--a type of parallel manipulators similar to a Stewart platform. The goal of this research is to develop an effective control scheme, cross-coupling control, for this type of CNC machine tools, which will reduce the contouring errors and thus further enhance their advantages. This dissertation describes the research work as follows. Firstly. based on the analysis of the kinematics and dynamics, a PID (Proportional-Integral-Derivative) controller was designed for each leg of the hexapod CNC machine. Secondly, real-time contour error models were developed and verified to determine not only for the calculation of the contour errors of the hexapod CNC machine but also for the general case of any machine tools. Thirdly, the contour errors of the hexapod CNC machine were investigated for a conventional PID controller. The results indicate that the accuracy of the hexapod machine is better than the conventional CNC machine tools even for mismatched axes and load exertion. Finally, a cross-coupling control scheme was proposed for the purpose to enhance the contour accuracy of this new type of hexapod CNC machine tools. A cross-coupling controller design for a 2-DOF platform was performed to provide the guidelines. Then, a cross-coupling controller for the new type of hexapod CNC machine tools was designed by feeding back the contour error to each axis. The efficiency of the proposed cross-coupling controller was verified through simulations. The result shows that the proposed cross-coupling controller is very effective in reducing the contouring errors. While cross-coupling controllers were originally proposed for conventional CNC machine tools, this research is the first attempt of expanding this concept to the new type of hexapod CNC machine tools.
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Date Issued: 1998
PURL: http://purl.flvc.org/fcla/dt/12576
Subject Headings: Machine-tools--Numerical control, Manipulators (Mechanism), PID controllers
Format: Document (PDF)

Title: Hybrid telemanipulation simulation for mission rehearsal and intervention.
Creator: Agba, Emmanuel I., Florida Atlantic University, Wong, Tin-Lup, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A "hybrid" telerobotic simulation system that is suitable for telemanipulation rehearsal, operator training, human factors study and operator performance evaluation has been developed. The simulator also has the capabilities for eventual upgrade for supervisory control. It is capable of operation in the conventional rate-control, master/slave control and a data driven preprogrammed mode of operation. It has teach/playback capability which allows an operator to generate joint commands for real...
Show moreA "hybrid" telerobotic simulation system that is suitable for telemanipulation rehearsal, operator training, human factors study and operator performance evaluation has been developed. The simulator also has the capabilities for eventual upgrade for supervisory control. It is capable of operation in the conventional rate-control, master/slave control and a data driven preprogrammed mode of operation. It has teach/playback capability which allows an operator to generate joint commands for real time teleoperation. For high-level task execution, the operator selects a specific task from a set of menu options and the simulator automatically generates the required joint commands. The simulator was developed using a three dimensional graphic model of an increasingly popular manipulator, TITAN 7F. A closed-form solution for inverse kinematics of the manipulator was found. Degeneracies from inverse kinematics solutions were observed to exist for certain arm configurations, although the manipulator can physically attain such configurations. An approach based on known facts about the manipulator geometry and physical constraints coupled with heuristics was used to generate physically attainable joint solutions from the inverse kinematics. The conditions that cause solution degeneracy were demonstrated to be related to singularity conditions. A novel object interaction detection strategy was implemented for more realistic telemanipulation. The object detection technique was developed based on the use of superellipsoid, which has a convenient inside-outside function for interference testing. The manipulator, with its end-effector and payloads, if any, were modeled as superquadric ellipsoids. A systematic way of determining transformation matrices between the superquadric manipulator links was developed. The interaction detection technique treats both moving and stationary objects in a consistent manner and has proved to be easy to implement and optimize for real-time applications. The feature has been applied for the simulation of pick-and-place operations and collision detection. It is also used to provide visual feedback as a low-cost force reflection and can be interfaced with a bilateral controller for force reflection simulation.
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Date Issued: 1991
PURL: http://purl.flvc.org/fcla/dt/12278
Subject Headings: Manipulators (Mechanism), Remote control, Vehicles, Remotely piloted, Remote submersibles
Format: Document (PDF)

Title: Workspace evaluation and kinematic calibration of Stewart platform.
Creator: Wang, Jian., Florida Atlantic University, Masory, Oren, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Parallel manipulators have their special characteristics in contrast to the traditional serial type of robots. Stewart platform is a typical six degree of freedom fully parallel robot manipulator. The goal of this research is to enhance the accuracy and the restricted workspace of the Stewart platform. The first part of the dissertation discusses the effect of three kinematic constraints: link length limitation, joint angle limitation and link interference, and kinematic parameters on the...
Show moreParallel manipulators have their special characteristics in contrast to the traditional serial type of robots. Stewart platform is a typical six degree of freedom fully parallel robot manipulator. The goal of this research is to enhance the accuracy and the restricted workspace of the Stewart platform. The first part of the dissertation discusses the effect of three kinematic constraints: link length limitation, joint angle limitation and link interference, and kinematic parameters on the workspace of the platform. An algorithm considering the above constraints for the determination of the volume and the envelop of Stewart platform workspace is developed. The workspace volume is used as a criterion to evaluate the effects of the platform dimensions and kinematic constraints on the workspace and the dexterity of the Stewart platform. The analysis and algorithm can be used as a design tool to select dimensions, actuators and joints in order to maximize the workspace. The remaining parts of the dissertation focus on the accuracy enhancement. Manufacturing tolerances, installation errors and link offsets cause deviations with respect to the nominal parameters of the platform. As a result, if nominal parameters are being used, the resulting platform pose will be inaccurate. An accurate kinematic model of Stewart platform which accommodates all manufacturing and installation errors is developed. In order to evaluate the effects of the above factors on the accuracy, algorithms for the forward and inverse kinematics solutions of the accurate model are developed. The effects of different manufacturing tolerances and installation errors on the platform accuracy are investigated based on this model. Simulation results provide insight into the expected accuracy and indicate the major factors contributing to the inaccuracies. In order to enhance the accuracy, there is a need to calibrate the platform, or to determine the actual values of the kinematic parameters (Parameter Identification) and to incorporate these into the inverse kinematic solution (Accuracy Compensation). An error-model based algorithm for the parameter identification is developed. Procedures for the formulation of the identification Jacobian and for accuracy compensation are presented. The algorithms are tested using simulated measurements in which the realistic measurement noise is included. As a result, pose error of the platform are significantly reduced.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/12316
Subject Headings: Robots--Control systems, Manipulators (Mechanism), Robotics--Calibration
Format: Document (PDF)

Title: Self-calibration of parallel-link mechanisms.
Creator: Liu, Lixin., Florida Atlantic University, Zhuang, Hanqi, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: Self-calibration is a desirable feature for an intelligent machine such as a robot that must function outside of controlled laboratory conditions. This is because it is inevitable that variations in the kinematic model arise from imperfections in the manufacturing process and changes of environment conditions. Self-calibration has the potential of (a) removing the dependence on external pose sensing, (b) producing high accuracy measurement data over the entire workspace of the system with an...
Show moreSelf-calibration is a desirable feature for an intelligent machine such as a robot that must function outside of controlled laboratory conditions. This is because it is inevitable that variations in the kinematic model arise from imperfections in the manufacturing process and changes of environment conditions. Self-calibration has the potential of (a) removing the dependence on external pose sensing, (b) producing high accuracy measurement data over the entire workspace of the system with an extremely fast measurement rate, (c) being automated and completely non invasive, (d) facilitating on-line accuracy compensation, and (e) being cost effective. This dissertation concentrates on the study of self-calibrating parallel-link mechanisms. A framework of self-calibration of a parallel-link mechanism is created, which is based on kinematic analysis and the construction of measurement residuals utilizing the information provided by redundant sensors embedded in the system. Forward and inverse kinematic measurement residuals of the mechanisms are proposed. To avoid the estimation of redundant kinematic parameters of the mechanism, the concept of relative residuals is introduced. Guidelines for placement of sensors for self-calibration are presented. An approach to determining the number of independent kinematic parameters of the mechanism is introduced. Extensive simulation and experimental studies conducted on a parallel-link mechanism, the Stewart platform built in the Robotics Center at Florida Atlantic University, confirm the effectiveness of the proposed approach.
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Date Issued: 1997
PURL: http://purl.flvc.org/fcla/dt/12539
Subject Headings: Manipulators (Mechanism)--Calibration, Robots--Control systems, Robotics
Format: Document (PDF)

Title: An adaptive computed torque controller for the I.B.M. Electric Drive Robot.
Creator: Miller, Lee Wayne., Florida Atlantic University, Pajunen, Grazyna, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
Abstract/Description: The I.B.M. Electric Drive Robot (E.D.R.) is a six-link manipulator originally controlled by a classical analog P.I.D. controller. Its performance is not satisfactory because of its poor tracking capabilities and a considerable vibration during arm movement. This is the central motivation for designing an adaptive computed torque controller for this system. In order to accomplish this the physical model of the robot is first reparameterized such that it is linear with respect to a set of...
Show moreThe I.B.M. Electric Drive Robot (E.D.R.) is a six-link manipulator originally controlled by a classical analog P.I.D. controller. Its performance is not satisfactory because of its poor tracking capabilities and a considerable vibration during arm movement. This is the central motivation for designing an adaptive computed torque controller for this system. In order to accomplish this the physical model of the robot is first reparameterized such that it is linear with respect to a set of uncertain parameters. Once this is accomplished the adaptive controller is then formulated. Next methods of computer simulation are developed and employed. These simulation results show the superior performance of the proposed scheme over both a classical computed torque controller and the current P.I.D. controller.
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Date Issued: 1990
PURL: http://purl.flvc.org/fcla/dt/14612
Subject Headings: Adaptive control systems--Computer simulation, PID controllers--Computer simulation, Robotics, Manipulators (Mechanism)
Format: Document (PDF)

Title: Development of a graphical user interface for a Stewart platform.
Creator: Subramanian, Chenthilvel Muthukumaran., Florida Atlantic University, Masory, Oren, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: A user friendly graphical interface was developed to control a Stewart platform which is a six degree-of-freedom in-parallel mechanism. The interface allows the user to define the platform motion relative to various coordinate systems: base, platform and joint. The velocity/position reference to the platform's controller can be provided by the following ways: preprogrammed data file, serial communication RS-232, 6 degrees of freedom joystick and soft teach pendant. The platform was designed...
Show moreA user friendly graphical interface was developed to control a Stewart platform which is a six degree-of-freedom in-parallel mechanism. The interface allows the user to define the platform motion relative to various coordinate systems: base, platform and joint. The velocity/position reference to the platform's controller can be provided by the following ways: preprogrammed data file, serial communication RS-232, 6 degrees of freedom joystick and soft teach pendant. The platform was designed to be used as "Space Emulator" and therefore a 6 degrees of freedom force/torque sensor was needed. Two different models of such sensors were designed and analyzed using finite element analysis techniques. Based on the results one particular model was selected, fabricated, instrumented with strain gages and calibrated in order to obtain its stiffness matrix. The effect of drifting of the sensor output due to self heating of the strain gages and the electronic components of the strain gage amplifiers was also studied.
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Date Issued: 1993
PURL: http://purl.flvc.org/fcla/dt/14941
Subject Headings: Robots--Control systems, Robotics--Calibration, Manipulators (Mechanism), Finite element method, Graphical user interfaces (Computer systems)
Format: Document (PDF)

Title: Development of a morphing autonomous underwater vehicle for path and station keeping in complex current environments.
Creator: Meneses, Andrea M., Su, Tsung-Chow, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This thesis explores the feasibility of using morphing rudders in autonomous underwater vehicles (AUVs) to improve their performance in complex current environments. The modeling vehicle in this work corresponds to the Florida Atlantic University's Ocean EXplorer (OEX) AUV. The AUV nonlinear dynamic model is limited to the horizontal plane and includes the effect of ocean current. The main contribution of this thesis is the use of active rudders to successfully achieve path keeping and...
Show moreThis thesis explores the feasibility of using morphing rudders in autonomous underwater vehicles (AUVs) to improve their performance in complex current environments. The modeling vehicle in this work corresponds to the Florida Atlantic University's Ocean EXplorer (OEX) AUV. The AUV nonlinear dynamic model is limited to the horizontal plane and includes the effect of ocean current. The main contribution of this thesis is the use of active rudders to successfully achieve path keeping and station keeping of an AUV under the influence of unsteady current force. A constant ocean current superimposed with a sinusoidal component is considered. The vehicle's response is analyzed for a range of current frequencies.
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Date Issued: 2014
PURL: http://purl.flvc.org/fau/fd/FA00004137, http://purl.flvc.org/fau/fd/FA00004137
Subject Headings: Autonomous robots -- Design and construction, Fracture mechanics, Manipulation (Mechanism) -- Control, Remote submersibles -- Design and construction, Vehicles, Remotely piloted -- Design and construction
Format: Document (PDF)

Manipulators (Mechanism) (9)	+ -
Robots--Control systems (5)	+ -
Algorithms (2)	+ -
Control theory (2)	+ -
Robotics (2)	+ -

Robotics--Calibration (2)	+ -
Adaptive control systems--Computer simulation (1)	+ -
Autonomous robots -- Design and construction (1)	+ -
Finite element method (1)	+ -
Fracture mechanics (1)	+ -
Graphical user interfaces (Computer systems) (1)	+ -
Machine-tools--Numerical control (1)	+ -
Manipulation (Mechanism) -- Control (1)	+ -
Manipulators (Mechanism)--Calibration (1)	+ -
PID controllers (1)	+ -
PID controllers--Computer simulation (1)	+ -
Remote control (1)	+ -
Remote submersibles (1)	+ -
Remote submersibles -- Design and construction (1)	+ -
Robots (1)	+ -
Vehicles, Remotely piloted (1)	+ -
Vehicles, Remotely piloted -- Design and construction (1)	+ -

Florida Atlantic University (11)	+ -
College of Engineering and Computer Science (10)	+ -
Department of Computer and Electrical Engineering and Computer Science (5)	+ -
Department of Ocean and Mechanical Engineering (5)	+ -
Masory, Oren (4)	+ -

Roth, Zvi S. (2)	+ -
Zhuang, Hanqi (2)	+ -
Zilouchian, Ali (2)	+ -
Agba, Emmanuel I. (1)	+ -
Gautam, Ashutosh. (1)	+ -
Hamano, Fumio (1)	+ -
Liu, Lixin. (1)	+ -
Marquis, Lawrence Paul. (1)	+ -
Meneses, Andrea M. (1)	+ -
Miller, Lee Wayne. (1)	+ -
Pajunen, Grazyna (1)	+ -
Su, Tsung-Chow (1)	+ -
Subramanian, Chenthilvel Muthukumaran. (1)	+ -
Wang, Jian. (1)	+ -
Wong, Tin-Lup (1)	+ -
Xiu, Daoxi. (1)	+ -
Xu, Hua. (1)	+ -

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