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Pages
 Title
 A bioengineering approach for rational vaccine design towards the Ebola Virus.
 Creator
 Banton, Sophia, Roth, Zvi S., Pavlovic, Mirjana
 Date Issued
 20100709
 PURL
 http://purl.flvc.org/fcla/dt/3326718
 Subject Headings
 Bioengineering, Ebolavirus
 Format
 Document (PDF)
 Title
 ROBOT CALIBRATION USING STEREO VISION.
 Creator
 CHEN, SHOUPU., Florida Atlantic University, Roth, Zvi S., Sudhakar, Raghavan
 Abstract/Description

This thesis deals with a study of using the stereo vision technique in the robot calibration. Three cameras are used in measurement to extract the position information of a target point attached onto each of the robot manipulator links for the purpose of identifying the actual kinematic parameters of every link of the robot manipulator under testing. The robot kinematic model used in this study is the SModel which is an extension of the wellknown DenavitHartenberg model. The calibration...
Show moreThis thesis deals with a study of using the stereo vision technique in the robot calibration. Three cameras are used in measurement to extract the position information of a target point attached onto each of the robot manipulator links for the purpose of identifying the actual kinematic parameters of every link of the robot manipulator under testing. The robot kinematic model used in this study is the SModel which is an extension of the wellknown DenavitHartenberg model. The calibration has been done on the wrist of the IBM 7565 robot. The experiment setup and results and the necessary software are all presented in this thesis.
Show less  Date Issued
 1987
 PURL
 http://purl.flvc.org/fcla/dt/14416
 Subject Headings
 RoboticsCalibrationMeasurement
 Format
 Document (PDF)
 Title
 Nonlinear control of underactuated horizontal double pendulum.
 Creator
 Popescu, Cristian., Florida Atlantic University, Wang, Yuan, Roth, Zvi S.
 Abstract/Description

Underactuated mechanical systems are those possessing fewer actuators than degrees of freedom, making the class a rich one from a control standpoint. The double inverted pendulum is a particular underactuated system and a wellknown benchmark case for which many solutions have been offered in the literature. The control objective is to bring the system to its unstable top equilibrium point. The underactuated horizontal double pendulum is a twolink planar robot with only one actuator either...
Show moreUnderactuated mechanical systems are those possessing fewer actuators than degrees of freedom, making the class a rich one from a control standpoint. The double inverted pendulum is a particular underactuated system and a wellknown benchmark case for which many solutions have been offered in the literature. The control objective is to bring the system to its unstable top equilibrium point. The underactuated horizontal double pendulum is a twolink planar robot with only one actuator either at the shoulder or the elbow. Almost no work was done on the underactuated horizontal pendulum, mainly due to the lack of controllability of such a system. The fundamental difference between a double inverted pendulum and an underactuated horizontal double pendulum is that in the latter gravity effects do not exist. Gravity is important to the controllability of the system. Thus, in search for a "gravity substitute," we added springs in the underactuated horizontal double pendulum in order to create a source of potential energy. Two different types of such systems are analyzed: spring coupled underactuated horizontal double pendulums and underactuated horizontal double pendulums with springloaded sliding bar constraint. The main contribution of the thesis is in proving that the zero state of the spring coupled systems is globally asymptotically stabilizable. Explicit control laws were developed.
Show less  Date Issued
 2002
 PURL
 http://purl.flvc.org/fcla/dt/12894
 Subject Headings
 Double pendulums, Nonlinear control theory
 Format
 Document (PDF)
 Title
 A simplified Jacobian representation for robot manipulators.
 Creator
 Alewine, Neal Jon., Florida Atlantic University, Roth, Zvi S.
 Abstract/Description

Central to many manipulator positional control schemes is a requirement to invert the forward kinematic equations which model the given manipulator. It is shown in this thesis that for manipulator types where a common wrist center exists, a simplified Jacobian form is feasible and its inversion can be used in place of inverse kinematic solutions for positional control. The Jacobian simplification is obtained by decoupling of the wrist member from the positional member, resulting in a Jacobian...
Show moreCentral to many manipulator positional control schemes is a requirement to invert the forward kinematic equations which model the given manipulator. It is shown in this thesis that for manipulator types where a common wrist center exists, a simplified Jacobian form is feasible and its inversion can be used in place of inverse kinematic solutions for positional control. The Jacobian simplification is obtained by decoupling of the wrist member from the positional member, resulting in a Jacobian inversion involving the solution of two sets of three equations with three unknowns. Within the development of the alternate Jacobian form, a technique for substituting incremental rotations with incremental translations is introduced yielding better insight into the Jacobian structure. A requirement for small moves is validated with a discussion of a proposed positional control strategy and a comprehensive example is presented as a summary of the results.
Show less  Date Issued
 1988
 PURL
 http://purl.flvc.org/fcla/dt/14477
 Subject Headings
 Robots, Manipulators (Mechanism), Matrices
 Format
 Document (PDF)
 Title
 KALMAN FILTERING FOR ROBOTIC CALIBRATION.
 Creator
 ELBALAH, OUSSAMA NAJIB RAWDAH., Florida Atlantic University, Roth, Zvi S.
 Abstract/Description

This thesis is concerned with the use of calibration techniques to increase robot accuracy. It is mainly an overview of some of the problems involved in the identification phase of calibration. A robot error model is developed and Kalman filtering algorithm is used in the identification of robot kinematic error parameters. Computer simulations and examples are used to study the behavior of the Kalman filter and its theoretical advantages in robot calibration.
 Date Issued
 1987
 PURL
 http://purl.flvc.org/fcla/dt/14370
 Subject Headings
 RoboticsCalibration, Kalman filtering
 Format
 Document (PDF)
 Title
 An empirical methodology for foundry specific submicroncmos analog circuit design.
 Creator
 RivasTorres, Wilfredo, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

Analog CMOS amplifiers are the building blocks for many analog circuit applications such as Operational Amplifiers, Comparators, Analog to Digital converters and others. This dissertation presents empirical design methodologies that are both intuitive and easy to follow on how to design these basic building blocks. The design method involves two main phases. In the first phase NMOS and PMOS transistor design kits, provided by a semiconductor foundry, are fully characterized using a set of...
Show moreAnalog CMOS amplifiers are the building blocks for many analog circuit applications such as Operational Amplifiers, Comparators, Analog to Digital converters and others. This dissertation presents empirical design methodologies that are both intuitive and easy to follow on how to design these basic building blocks. The design method involves two main phases. In the first phase NMOS and PMOS transistor design kits, provided by a semiconductor foundry, are fully characterized using a set of simulation experiments. In the second phase the user is capable of modifying all the relevant circuit design parameters while directly observing the tradeoffs in the circuit performance specifications. The final design is a circuit that very closely meets a set of desired design specifications for the design parameters selected. That second phase of the proposed design methodology utilizes a graphical user interface in which the designer moves a series of sliders allowing assessment of various design tradeoffs. The theoretical basis for this design methodology involves the transconductance efficiency and inversion coefficient parameters. In this dissertation there are no restrictive assumptions about the MOS transistor models. The design methodology can be used with any submicron model supported by the foundry process and in this sense the methods included within are general and nondependent on any specific MOSFET model (e.g. EKV or BSIM3). As part of the design tradeoffs assessment process variations are included during the design process rather than as part of some postnominaldesign analysis. One of the central design parameters of each transistor in the circuit is the MOSFET inversion coefficient. The calculation of the inversion coefficient necessitates the determination of an important process parameter known as the Technology Current. In this dissertation a new method to determine the technology current is developed. Y Parameters are used to characterize the CMOS process and this also helps in improving the technology current determination method. A study of the properties of the technology current proves that indeed a single long channel saturated MOS transistor can be used to determine a fixed technology current value that is used in subsequent submicron CMOS design. Process corners and the variability of the technology current are also studied and the universality of the transconductance efficiency versus inversion coefficient response is shown to be true even in the presence of process variability.
Show less  Date Issued
 2013
 PURL
 http://purl.flvc.org/fau/fd/FA0004050
 Subject Headings
 Electron transport, Integrated circuits  Design and construction, Metal oxide semiconductors, Complementary  Mathematical models
 Format
 Document (PDF)
 Title
 Design considerations in highthroughput automation for biotechnology protocols.
 Creator
 Cardona, Aura, Roth, Zvi S., Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

In this dissertation a computeraided automation design methodology for biotechnology applications is proposed that leads to several design guidelines. Because of the biological nature of the samples that propagate in the automation line, a very specific set of environmental and maximum allowed shelf time conditions have to be followed to obtain good yield. In addition all biotechnology protocols require precise sequence of steps, the samples are scarce and the reagents are costly, so no...
Show moreIn this dissertation a computeraided automation design methodology for biotechnology applications is proposed that leads to several design guidelines. Because of the biological nature of the samples that propagate in the automation line, a very specific set of environmental and maximum allowed shelf time conditions have to be followed to obtain good yield. In addition all biotechnology protocols require precise sequence of steps, the samples are scarce and the reagents are costly, so no waste can be afforded.
Show less  Date Issued
 2014
 PURL
 http://purl.flvc.org/fau/fd/FA00004272, http://purl.flvc.org/fau/fd/FA00004272
 Subject Headings
 Biotechnological process control, Biotechnological process monitoring, Molecular biology  Automation, Molecular biology  Technique, Molecular cloning  Technique, Pharmacognosy
 Format
 Document (PDF)
 Title
 Modeling errors in Kalman filters.
 Creator
 Xu, Hua., Florida Atlantic University, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

This thesis focuses on the performance of the Kalman filters for scalar timeinvariant systems when modeling errors are present. A complete classification of errors according to their effect on the filter performance is carried. Certain errors may drive the Kalman filter into instability. Other errors affect only certain statistical properties of the innovations process. Some of the results have been extended to the scalar timevarying and vector time invariant filtering problems.
 Date Issued
 1988
 PURL
 http://purl.flvc.org/fcla/dt/14435
 Subject Headings
 Kalman filtering
 Format
 Document (PDF)
 Title
 Nonlinear filtering techniques for failure detection in dynamic systems.
 Creator
 Ruokonen, Tuula., Florida Atlantic University, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

Developing online methods for detecting and locating process malfunctions is an important goal towards full automation of systems. Modelbased methods, which check the consistency of the observations using the known functional relationships among the process variables seem to have the potential of early detection of slowly developing failures in complex systems. This dissertation deals with nonlinear filtering as a method for failure detection in dynamic processes. The failure detection...
Show moreDeveloping online methods for detecting and locating process malfunctions is an important goal towards full automation of systems. Modelbased methods, which check the consistency of the observations using the known functional relationships among the process variables seem to have the potential of early detection of slowly developing failures in complex systems. This dissertation deals with nonlinear filtering as a method for failure detection in dynamic processes. The failure detection problem is presented here as an Identification Problem, where no jumps between the possible operating modes are assumed, i.e. there is only uncertainty with regard to which is the present mode. The identification filter consists of parallel Kalman filters, each tuned to a different system mode of operation, whose estimates parametrize the conditional probability equations. An extension of the filter is derived for the case of different measurement noise coefficients in different modes for the continuousdiscrete case. In the continuoustime case with different measurement noise intensities the likelihood function is shown to be illdefined as the induced measures become singular. The average performance of the continuousdescrete as well as the continuoustime identification filters are studied. It is shown that on the average and after a sufficiently long time a correct decision is expected for any decision threshold level. An alternative identification filter structure is derived using the maximumlikelihood estimation philosophy. The filter reduces to parallel Kalman filters, feeding the state estimates to a maximum likelihood generator which then chooses a set of indicator functions to maximize the total likelihood. Some aspects of interpreting a sequence of decisions, choosing a decision threshold and reinitializing the filter are discussed qualitatively using simulation examples. Furthermore, a new approach based on scaling of the likelihood functions is presented. Scaling is shown to be equivalent to choosing a threshold level for the conditional probabilities.
Show less  Date Issued
 1989
 PURL
 http://purl.flvc.org/fcla/dt/12238
 Subject Headings
 Kalman filtering
 Format
 Document (PDF)
 Title
 A study on glucose metabolism: Computer simulation and modeling.
 Creator
 Leesirikul, Meta., Florida Atlantic University, Neelakanta, Perambur S., Roth, Zvi S., Morgera, Salvatore D., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

Sorensen's model of glucose metabolism and regulation is reconstructed using SimulinkRTM. Most of the existing glucose metabolism models consist of several mass balance equations that interact with each others. Graphical format used by SimulinkRTM provides a visualized perspective of such relations so that it is easier to modify the model on ad hoc basis. TypeI and TypeII diabetes with relevant clinical details are simulated. Further, a control strategy is introduced in order to simulate...
Show moreSorensen's model of glucose metabolism and regulation is reconstructed using SimulinkRTM. Most of the existing glucose metabolism models consist of several mass balance equations that interact with each others. Graphical format used by SimulinkRTM provides a visualized perspective of such relations so that it is easier to modify the model on ad hoc basis. TypeI and TypeII diabetes with relevant clinical details are simulated. Further, a control strategy is introduced in order to simulate the control of exogenous insulin pump. Simulated results are consistent with available clinical data. Living systems in general, exhibit both stochastical and deterministic characteristics. Activities such as glucose metabolism traditionally modeled do not include stochastical properties, nor that they are viewed in the large framework of complex system with explicit interaction details. Currently, a complexity system model is developed to describe the glucose metabolism related activities. The simulation results obtained thereof illustrate the bounding domain of variations in some clinically observed details.
Show less  Date Issued
 2005
 PURL
 http://purl.flvc.org/fcla/dt/13254
 Subject Headings
 GlucoseMetabolism, Computer simulation, DiabetesMetabolism, Computer modeling
 Format
 Document (PDF)
 Title
 Camera calibration techniques.
 Creator
 Xu, Xuan., Florida Atlantic University, Roth, Zvi S., Zhuang, Hanqi, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

In order to facilitate the implementation of RACbased camera calibration technique, several issues are addressed in this thesis. First, a straightforward extension of the RACbased camera calibration technique to the case of unknown camera specifications is given. Second, to speed up the calibration process and reduce numerical difficulties, a simplified RACbased method is presented. The simplified RACbased method provides a closedform solution to the camera calibration problem. Third,...
Show moreIn order to facilitate the implementation of RACbased camera calibration technique, several issues are addressed in this thesis. First, a straightforward extension of the RACbased camera calibration technique to the case of unknown camera specifications is given. Second, to speed up the calibration process and reduce numerical difficulties, a simplified RACbased method is presented. The simplified RACbased method provides a closedform solution to the camera calibration problem. Third, the PTMbased camera calibration technique is presented to give an example of pre1985 camera calibration technique. Fourth, a method is devised to compute the ratio of scale factors. Finally, an optimization scheme is suggested to estimate image center. These modifications preserve all the advantages possessed by the original RACbased calibration technique. The experiment results are provided to illustrate the effectiveness of the present methods.
Show less  Date Issued
 1991
 PURL
 http://purl.flvc.org/fcla/dt/14771
 Subject Headings
 CamerasCalibration
 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.
Show less  Date Issued
 1992
 PURL
 http://purl.flvc.org/fcla/dt/12291
 Subject Headings
 Algorithms, Manipulators (Mechanism), RobotsControl systems
 Format
 Document (PDF)
 Title
 Design and implementation of a control system for a lasertracking measurement system.
 Creator
 Bai, Ying., Florida Atlantic University, Roth, Zvi S., Zhuang, Hanqi, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

To assess and evaluate the performance of robots and machine tools dynamically, it is desirable to have a precision measuring device that performs dynamic measurement of endeffector positions of such robots and machine tools. Among possible measurement techniques, Laser Tracking Systems (LTSs) exlnbit the capability of high accuracy, large workspace, high sampling rate, and automatic targettracking,. and thus are wellsuited for robot calibration both kinematically and dynamically. In this...
Show moreTo assess and evaluate the performance of robots and machine tools dynamically, it is desirable to have a precision measuring device that performs dynamic measurement of endeffector positions of such robots and machine tools. Among possible measurement techniques, Laser Tracking Systems (LTSs) exlnbit the capability of high accuracy, large workspace, high sampling rate, and automatic targettracking,. and thus are wellsuited for robot calibration both kinematically and dynamically. In this dissertation, the design and implementation of a control system for a homemade laser tracking measurement systems is addressed and calibration of a robot using the laser tracking system is demonstrated Design and development of a control system for a LTS is a challenging task. It involves a deep understanding of laser interferometry,. controls, mechanics and optics,. both in theoretical perspective and in implementation aspect. One of the most important requirements for a successful design and implementation of a control system for the LTS is proper installation and alignment of the laser and optical system,. or laser transducer system. The precision of measurement using the LTS depends highly on the accuracy of the laser transducer system, as well as the accuracy of the installation and alignment of the optical system. Hence, in reference to the experimental alignment method presented in this dissertation, major error sources affecting the system measurement accuracy are identified and analyzed. A manual compensation method is developed to eliminate the effects of these error sources effectively in the measurement system. Considerations on proper design and installation of laser and optical components are indicated in this dissertation. As a part of the conventional control system design, a dynamic system model of the LTS is required. In this study, a detailed derivation and analysis of the dynamic model of the motor gimbal system using LagrangeEuler equations of motion is developed for both ideal and complete gimbal systems. Based on this system model,. a conventional controller is designed. Fuzzy Logic Controllers (FLC) are designed in order to suppress noise or disturbances that exist in the motor driver subsystem. By using the relevant control strategies. noise and disturbances present in the electrical control channels are shown to reduce significantly. To improve the system performance further, a spectrum analysis of the error sources and disturbances existing in the system is conducted. Major noise sources are effectively suppressed by using a twostage fuzzy logic control strategy. A comparison study on the performances of different control strategies is given in this dissertation, in reference to the following: An ideal system model, a system with a long time delay, a system with various noise sources and a system model with uncertainties. Both simulation and experimental results are furnished to illustrate the advantages of the FLC in respect of its transient response, steadystate response, and tracking performance. Furthermore, noise reduction in the laser tracking system is demonstrated. Another important issue concerning a successful application of the LTS in the calibration of a robot is the estimation of system accuracy. Hence, a detailed analysis of system accuracy of the LTS is presented in this worL This analysis is also verified by experimental methods by means of tracking a Coordinate Measuring Machine available in the FAU Robotics Center. Using the developed LTS, a PUMA robot in the FAU Robotics Center is calibrated. The results obtained are confirmative with the data available in the literature. In summary, the proposed methodology towards the design and implementation of a control system for LTSs has been shown to be successful by performing experimental tracking and calibration studies at the FAU Robotics Center.
Show less  Date Issued
 2000
 PURL
 http://purl.flvc.org/fcla/dt/12622
 Subject Headings
 RobotsCalibration, RobotsControl systems, Fuzzy logic
 Format
 Document (PDF)
 Title
 THE DYNAMICS OF THE GENERALIZED MANIPULATOR.
 Creator
 LAU, TOCHOI., Florida Atlantic University, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

The concept of "generalized manipulator" is introduced, and the closed form and recursive form dynamical models of the generalized manipulator are presented in NewtonEuler formulation. The physical meaning of each term in the dynamical model is explained. The dynamical models formulated by the NewtonEuler method and the LagrangianEuler method are proved equivalent. The dynamical model of the generalized manipulator is reduced to ordinary manipulators. The reduced dynamical model is shown...
Show moreThe concept of "generalized manipulator" is introduced, and the closed form and recursive form dynamical models of the generalized manipulator are presented in NewtonEuler formulation. The physical meaning of each term in the dynamical model is explained. The dynamical models formulated by the NewtonEuler method and the LagrangianEuler method are proved equivalent. The dynamical model of the generalized manipulator is reduced to ordinary manipulators. The reduced dynamical model is shown identical to existing models. Furthermore, the reduced dynamical model of the generalized manipulator can be used to compute forces and torques components along any direction. Application of the model to problems of mobile robots and flexible manipulators is shown.
Show less  Date Issued
 1985
 PURL
 http://purl.flvc.org/fcla/dt/14243
 Subject Headings
 Manipulators (Mechanism), Robots
 Format
 Document (PDF)
 Title
 Robot singularities under small perturbations in the kinematic parameters.
 Creator
 Mohile, Ajey Avinash., Florida Atlantic University, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

When small perturbations in the kinematic parameters of a robot are taken into consideration, the model of a robot no longer contains perfect parallelism and perpendicularity that makes the nominal inverse kinematics so simple. In particular, the effect of joint axis misalignments and small perturbations in the kinematic parameters on the robot singularities is of interest. This aspect is particularly important when planning the workspace of a robot that must undergo calibration. To utilize...
Show moreWhen small perturbations in the kinematic parameters of a robot are taken into consideration, the model of a robot no longer contains perfect parallelism and perpendicularity that makes the nominal inverse kinematics so simple. In particular, the effect of joint axis misalignments and small perturbations in the kinematic parameters on the robot singularities is of interest. This aspect is particularly important when planning the workspace of a robot that must undergo calibration. To utilize the work volume most efficiently, one must know exactly what points are permissible as taught points. In other words, reachable workspace must be clearly defined to avoid the robot from entering the singularity zones not only of the nominal robot but also of all future actual robots. Once singularity zones for the actual robot are correctly identified, workspace planning becomes a simple task. In this thesis the relationship between small perturbations in kinematic parameters and singularities of a simple threerevolute articulated arm are studied. It is shown that singularities in such a robot do shift to new locations.
Show less  Date Issued
 1989
 PURL
 http://purl.flvc.org/fcla/dt/14476
 Subject Headings
 RobotsDynamics, RobotsMotion
 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 errormodel 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.
Show less  Date Issued
 1992
 PURL
 http://purl.flvc.org/fcla/dt/12316
 Subject Headings
 RobotsControl systems, Manipulators (Mechanism), RoboticsCalibration
 Format
 Document (PDF)
 Title
 Interactive computer aided digital control design.
 Creator
 Yakali, Huseyin Hakan., Florida Atlantic University, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

This thesis outlines the design philosophy and implementation aspects of a new interactive CAD tool implemented in BASIC language on an IBM PC/AT computer for single input single output (SISO) digital control systems. The direct Digital Control design method presented is classical in nature. The program main features are: (1) The use of Modified ztransform to model the effects of transport delay due to control computation time. (2) The use of windows on a split screen to allow the designer...
Show moreThis thesis outlines the design philosophy and implementation aspects of a new interactive CAD tool implemented in BASIC language on an IBM PC/AT computer for single input single output (SISO) digital control systems. The direct Digital Control design method presented is classical in nature. The program main features are: (1) The use of Modified ztransform to model the effects of transport delay due to control computation time. (2) The use of windows on a split screen to allow the designer observation of the closedloop step response while systematically shaping a root locus or synthesizing closedloop pole/zero patterns. (3) Display of system response in between sampling instants.
Show less  Date Issued
 1988
 PURL
 http://purl.flvc.org/fcla/dt/14488
 Subject Headings
 Computeraided design, Digital control systems, Engineering designData processing
 Format
 Document (PDF)
 Title
 Kinematic modeling, identification and compensation of robot manipulators.
 Creator
 Zhuang, Hanqi, Florida Atlantic University, Hamano, Fumio, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

Theoretical and practical issues of kinematic modeling, measurement, identification and compensation are addressed in this dissertation. A comprehensive robot calibration methodology using a new Complete and Parametrically Continuous (CPC) kinematic model is presented. The dissertation focuses on modelbased robot calibration techniques. Parametric continuity of a kinematic model is defined and discussed to characterize model singularity. Irreducibility is defined to facilitate error model...
Show moreTheoretical and practical issues of kinematic modeling, measurement, identification and compensation are addressed in this dissertation. A comprehensive robot calibration methodology using a new Complete and Parametrically Continuous (CPC) kinematic model is presented. The dissertation focuses on modelbased robot calibration techniques. Parametric continuity of a kinematic model is defined and discussed to characterize model singularity. Irreducibility is defined to facilitate error model reduction. Issues of kinematic parameter identification are addressed by utilizing generic forms of linearized kinematic error models. The CPC model is a complete and parametrically continuous kinematic model capable of describing geometry and motion of a robot manipulator. Owing to the completeness of the CPC model, the transformation from the base frame to the world frame and from the tool frame to the last link frame can be modeled with the same modeling convention as the one used for internal link transformations. Due to the parametric continuity of the CPC model, numerical difficulties in kinematic parameter identification using error models are reduced. The CPC model construction, computation of the link parameters from a given link transformation, inverse kinematics, transformations between the CPC model and the DenavitHartenberg model, and linearized CPC error model construction are investigated. New methods for selfcalibration of a laser tracking coordinatemeasuringmachine are reported. Two calibration methods, one based on a fourtracker system and the other based on three trackers with a precision plane, are proposed. Iterative estimation algorithms along with simulation results are presented. Linear quadratic regulator (LQR) theory is applied to design robot accuracy compensators. In the LQR algorithm, additive corrections of joint commands are found without explicitly solving the inverse kinematic problem for an actual robot; a weighting matrix and coefficients in the cost function can be chosen systematically to achieve specific objective such as emphasizing the positioning accuracy of the endeffector over its orientation accuracy and vice versa and taking into account joint travelling limits as well as singularity zones of the robot. The results of the kinematic identification and compensation experiments using the PUMA robot have shown that the CPC modeling technique presented in this dissertation is a convenient and effective means for accuracy improvements of industrial robots.
Show less  Date Issued
 1989
 PURL
 http://purl.flvc.org/fcla/dt/12243
 Subject Headings
 Robotics, Manipulators (Mechanism)
 Format
 Document (PDF)
 Title
 Selfcalibration 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 selfcalibration 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 selfcalibration strategies. In this dissertation, a kinematic model that describes not only the motion but also geometric variations of a multiplebeam 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 selfcalibration method was proposed to calibrate intelligent machines with planar constraints. The method is also applied to the selfcalibration 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 selfcalibration. 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 selfcalibration system under realworld 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
 RobotsKinematics, RoboticsCalibrationMeasurement, RobotsControl systems
 Format
 Document (PDF)
 Title
 Submicron CAD design and analysis of MOS Current Mirrors.
 Creator
 RivasTorres, Wilfredo, Florida Atlantic University, Roth, Zvi S., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
 Abstract/Description

Current Mirrors are widely used circuits in IC designs. They are used as current sources and loads. The proper selection of a Current Mirror configuration is therefore important. This thesis reviews critical parameters for Current Minors characterization. Six MOS Current Mirror configurations are studied, and their performance characteristics are compared. The proper selection and use of MOSFET models are presented. It is shown that CADbased design and analysis is indispensable if realistic...
Show moreCurrent Mirrors are widely used circuits in IC designs. They are used as current sources and loads. The proper selection of a Current Mirror configuration is therefore important. This thesis reviews critical parameters for Current Minors characterization. Six MOS Current Mirror configurations are studied, and their performance characteristics are compared. The proper selection and use of MOSFET models are presented. It is shown that CADbased design and analysis is indispensable if realistic MOS models such as BSIM3 are used. The CAD based analysis and design employs simulation parameter tuning, optimization and swept parameters. The presented CAD techniques allow a designer to make important tradeoffs for different configurations. One of the main thesis observations is that it is not always necessary to use more involved Current Mirror configurations; a Simple Current Mirror Configuration is often sufficient. The thesis also studies the adverse effects on the design caused by process variations.
Show less  Date Issued
 2004
 PURL
 http://purl.flvc.org/fcla/dt/13119
 Subject Headings
 Metal oxide semiconductorsComputeraided design, Integrated circuits, Metal oxide semiconductor fieldeffect transistors
 Format
 Document (PDF)