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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: Tool wear monitoring using artificial neural networks.
Creator: Kurapati, Venkatesh., Florida Atlantic University, Masory, Oren, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: An on-line scheme for monitoring tool wear in unmanned machining operations using artificial neural networks (ANNs) is proposed. Various configurations of ANNs are studied to increase the accuracy of tool wear estimation. With this aim three configurations of the ANNs namely, an ANN without memory, an ANN with one phase memory, and an ANN with two phase memory are considered. Each ANN is trained to associate an input vector which consists of values of cutting conditions, with an output vector...
Show moreAn on-line scheme for monitoring tool wear in unmanned machining operations using artificial neural networks (ANNs) is proposed. Various configurations of ANNs are studied to increase the accuracy of tool wear estimation. With this aim three configurations of the ANNs namely, an ANN without memory, an ANN with one phase memory, and an ANN with two phase memory are considered. Each ANN is trained to associate an input vector which consists of values of cutting conditions, with an output vector containing flank wear as a single output. The training data and evaluation data is generated using the popular analytical tool wear model. The performance of all the ANNs are compared by considering four different cases of evaluation data. The proposed scheme of tool wear modeling using ANNs is easily extendible to include other cutting parameters and can be implemented in real-time.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14868
Subject Headings: Neural networks (Computer science), Flexible manufacturing systems, Power tools, Machine tools--Data processing
Format: Document (PDF)

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.
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Date Issued: 1992
PURL: http://purl.flvc.org/fcla/dt/14814
Subject Headings: Tolerance (Engineering), Machinery, Kinematics of
Format: Document (PDF)

Title: A petri net framework for the simulation and control of automated systems.
Creator: Murgatroy, Richard John, Jr., Florida Atlantic University, Masory, Oren, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This thesis presents a programming framework in the C language to execute a petri net simulation and real-time control for an automated system. This framework allows for the simulation of a proposed flexible automated system, and also the simultaneous development of the real-time control. The system is based on petri nets, which are used to model the system. Basic petri net theory and the construction of models using petri nets are discussed. The program is designed to allow a hierarchical...
Show moreThis thesis presents a programming framework in the C language to execute a petri net simulation and real-time control for an automated system. This framework allows for the simulation of a proposed flexible automated system, and also the simultaneous development of the real-time control. The system is based on petri nets, which are used to model the system. Basic petri net theory and the construction of models using petri nets are discussed. The program is designed to allow a hierarchical structure to the petri net model, and a modular approach to the program design is taken using some concepts from object oriented programming. The program provides a time-based diagnostic system incorporated into the framework to detect problems during the execution of the actual system. An example application is provided to demonstrate the implementation of the framework to both simulate and control an actual system.
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Date Issued: 1995
PURL: http://purl.flvc.org/fcla/dt/15226
Subject Headings: Petri nets, Computer integrated manufacturing systems--Computer simulation, Flexible manufacturing systems--Computer simulation
Format: Document (PDF)

Title: A genetic algorithm for non-constrained process and economic process optimization.
Creator: Chirdchid, Sangthen., Florida Atlantic University, Masory, Oren, Mazouz, Abdel Kader, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: Improving the quality of a product and manufacturing processes at a low cost is an economic and technological challenge which quality engineers and researches must contend with. In general, the quality of products and their cost are the main concerns for manufactures. This is because improving quality is very crucial for staying competitive and improving the organization's market position. However, some difficulty of finding where the standard of good quality is still remains. Customers'...
Show moreImproving the quality of a product and manufacturing processes at a low cost is an economic and technological challenge which quality engineers and researches must contend with. In general, the quality of products and their cost are the main concerns for manufactures. This is because improving quality is very crucial for staying competitive and improving the organization's market position. However, some difficulty of finding where the standard of good quality is still remains. Customers' satisfaction is a key for setting up the quality target. One possible solution is to develop control limits, which are the limits for indicating the area of nonconforming product on the basis of minimizing the total cost or loss to the customer as well as to the manufacturer. Therefore, the goal of this dissertation is to develop an effective tool to improve a high quality of product while maintaining a minimum cost.
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Date Issued: 2004
PURL: http://purl.flvc.org/fau/fd/FADT12081
Subject Headings: Genetic algorithms, Quality of products--Cost effectiveness--Econometric models, Multivariate analysis, Taguchi methods (Quality control)
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 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: Analysis of factors affecting the sound generated by airboats.
Creator: Perez, Aquiles., Florida Atlantic University, Masory, Oren, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
Abstract/Description: This study presents an experimental and analytical investigation of the factors that affect the sound generated by airboats as well as the interaction among these factors; an airboat travels on water and wet land by means of an air pusher propeller attached to an internal combustion engine. These analyses show that the engine and propeller RPM are the main contributors of sound. The contribution of the engine is a tonal sound that is reduced by using a muffler. The sound generated by the...
Show moreThis study presents an experimental and analytical investigation of the factors that affect the sound generated by airboats as well as the interaction among these factors; an airboat travels on water and wet land by means of an air pusher propeller attached to an internal combustion engine. These analyses show that the engine and propeller RPM are the main contributors of sound. The contribution of the engine is a tonal sound that is reduced by using a muffler. The sound generated by the propeller is a flapping sound clearly identified at high revolutions (over 1800 RPM). Above mid-range speeds, the propeller sound takes over, and any reduction of sound on the muffler does not play any role. The only method to control the sound of an airboat without any design modifications is to maintain the operational RPM at mid-range when the muffler's devices contribute to the sound reduction.
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Date Issued: 2006
PURL: http://purl.flvc.org/fcla/dt/13347
Subject Headings: Internal combustion engines--Noise, Noise control
Format: Document (PDF)

Manipulators (Mechanism) (3)	+ -
Robots--Control systems (2)	+ -
Computer integrated manufacturing systems--Computer simulation (1)	+ -
Finite element method (1)	+ -
Flexible manufacturing systems (1)	+ -

Flexible manufacturing systems--Computer simulation (1)	+ -
Genetic algorithms (1)	+ -
Graphical user interfaces (Computer systems) (1)	+ -
Internal combustion engines--Noise (1)	+ -
Machine tools--Data processing (1)	+ -
Machine-tools--Numerical control (1)	+ -
Machinery, Kinematics of (1)	+ -
Multivariate analysis (1)	+ -
Neural networks (Computer science) (1)	+ -
Noise control (1)	+ -
PID controllers (1)	+ -
Petri nets (1)	+ -
Power tools (1)	+ -
Quality of products--Cost effectiveness--Econometric models (1)	+ -
Robotics--Calibration (1)	+ -
Taguchi methods (Quality control) (1)	+ -
Tolerance (Engineering) (1)	+ -

College of Engineering and Computer Science (8)	+ -
Florida Atlantic University (8)	+ -
Chirdchid, Sangthen. (1)	+ -
Kumar, Arun. (1)	+ -
Kurapati, Venkatesh. (1)	+ -

Marquis, Lawrence Paul. (1)	+ -
Mazouz, Abdel Kader (1)	+ -
Murgatroy, Richard John, Jr. (1)	+ -
Perez, Aquiles. (1)	+ -
Subramanian, Chenthilvel Muthukumaran. (1)	+ -
Xiu, Daoxi. (1)	+ -

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