Browsing by Subject "control"

Now showing 1 - 4 of 4
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    Airgap-less Electric Motor
    (2021-08) Alibeik, Maryam; dos Santos, Euzeli; King, Brian; Li, Lingxi; Rovnyak, Steven
    This dissertation focuses mainly on the airgap-less electric machine. An extensive literature review has been presented along with a systematic study that included analytical modeling, simulation with both steady-state and transient analysis, prototype building, and experimental validation. In this type of device, the rotor is allowed to touch the stator at a contact point, which maximizes the internal flux and therefore the electromagnetic torque. A higher torque density motor is proposed in this dissertation due to a reduced reluctance caused by zero airgap situation. A comparison with other high torque density electric machines demonstrates the advantages of the proposed machine. Switched reluctance motor for hybrid vehicle, integrated magnetic gear, induction machines, are some examples of the machines with lower torque density than the airgap-less electric machine. This machine will maximize the generated torque allowing these type of machines to be competitive in applications where hydraulic motors are prevalent, i.e., low-speed and high-torque requirements. Hydraulic motor systems face two major problems with their braking system and with low efficiency due to a large number of energy conversion stages (i.e., motor-pump, hydraulic connections and the hydraulic motor itself). The proposed electric motor, unlike hydraulic motors, converts electrical energy directly to mechanical energy with no extra braking system necessary and with higher efficiency. The evolution of the airgap-less electric machine from three poles to 9 bi-poles is discussed in this dissertation. The modeling of this machine with a minimum number of poles is discussed before a generalization is presented. The simulation and analysis of the airgap-less electric motor has been done using Euler integration method as well as Runge Kutta 4th order integration method due to its higher precision. A proof-of-concept electric machine with nine magnetic bipoles is built to validate the theoretical assumptions.
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    Hope, Optimism, and Affect as Predictors and Consequences of Expectancies: The Potential Moderating Roles of Perceived Control and Success
    (Elsevier, 2020) Shanahan, Mackenzie L.; Fischer, Ian C.; Rand, Kevin L.; Psychology, School of Science
    Hope and optimism may be differentially influential depending on the situational context. This study sought to (1) experimentally test whether hope and optimism differentially predict specific expectancies in controllable versus uncontrollable situations and (2) examine the relative impact of specific expectancies on affect when desired outcomes are (or are not) achieved. A 2 × 2 independent samples design was used to experimentally manipulate perceived control and situational outcome (i.e., success or failure). Online participants (N = 571) completed self-report measures of hope and optimism before being randomly assigned to one of four experimental conditions. Results showed that hope, but not optimism, predicted specific expectancies in the perceived control condition. Conversely, optimism, but not hope, predicted specific expectancies in the no perceived control condition. More optimistic specific expectancies of success predicted greater positive affect regardless of success or failure outcome.
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    LabVIEW™ Database Interfacing For Robotic Control
    (2006-07-26T14:13:05Z) Gebregziabher, Netsanet; Perry, Douglas G.
    The Zymark™ System is a lab automation workstation that uses the Caliper Life Sciences (Hopkinton, MA) Zymate XP robot. At Indiana University-Purdue University Indianapolis, a Zymate is used in a course, INFO I510 Data Acquisition and Laboratory Automation, to demonstrate the fundamentals of laboratory robotics. This robot has been re-engineered to function with National Instruments™ graphical software program LabVIEW™. LabVIEW is an excellent tool for robotic control. Based on changing conditions, it is able to dynamically use data from any source to modify the operating parameters of a robot. For dynamically changing information, storage of that information must be readily accessible. For example, there is a need to continuously store and update the calibration data of the robot, populate the setting of each axis and positioning inside the workplace, and also store robot positioning information. This can be achieved by using a database which allows for robotic control data to be easily searched and accessed. To address this need, an interface was developed which would allow full, dynamic communication between any LabVIEW program (called “virtual instruments,” or VIs) and the database. This has been accomplished by developing a set of subVIs that can be dropped into the calling robotic control VIs. With these subVIs, a user has the ability to create table and column information, delete a table, retrieve table information by clicking a particular table name on the user interface, or query using any SQL-specific combination of columns or tables within the database. For robot functionality, subVIs were created to store and retrieve data such as calibration data points and regression calculations.