This dissertation describes the development of an assist-device aimed to deliver 3D graphic information to the visually impaired people. A human-in-loop approach was used to analyze whether a virtual 3D shape can be transferred correctly to the human users.The proposed device in this dissertation consists of two major parts: (a) A system of position sensors for real time localization based on magnetization, and (b) A single vibratory actuator working at varied frequencies based on its real time location. The error bound of the position measurement was tested to be 2 mm, which defined the machine resolution of the shape display. In order to realize the refresh rate of the localization that can follow user's scanning speed, the parallel data processing sequences for computer and microcontroller were designed. Additionally, vibratory electromagnetic (EM) actuators were discussed based on eddy current and permanent magnet methods. The simulation study showed that eddy current method was not applicable for millimeter size coil. Accordingly, the permanent magnet method was developed and the force detection threshold of human tactile perceptions was studied.Virtual shape perception experiments were made with participation of 3 volunteers who were not aware of the 3D shape information prior to the tests. Based on the four sets of shape tests, we conclude that the majority of the shape information is able to be delivered to users by using the proposed device. Difficulties for perceiving the local sharp profile e.g. thin plates and large curvature in small shapes may be better addressed by multiple actuators simultaneously providing shape information in the local boundary detection.The major contribution of this dissertation is the 3D shape display implemented by a miniature and low cost device. The developed device utilizes both passive stimulation and active search so that a commonly used large scale actuators matrix based on mere active touch method is avoided. The studies on the required force/energy input from the actuator showed that EM actuators can be miniaturized to millimeter scale without sacrificing the ability to induce tactile stimulation. Additional uniqueness of the proposed system is the ability to present hollow features, which is impossible to display by the existing devices.

This Ph.D. thesis presents the design, modeling, optimization, prototyping, and experimental methodologies for a novel actuation system for the synchronized segmentally interchanging pulley transmission system (SSIPTS). The SSIPTS is an improved transmission which offers the combined benefits of existing transmission systems for the automotive, the power generation, and the heating, ventilation, and air conditioning (HVAC) industries. As a major subsystem of the SSIPTS, the Pulley Segment Actuation System (PSAS) plays a critical role in the SSIPTS operation and success. However, the overall design of the SSIPTS and its operation principle introduce very challenging and conflicting design requirements for PSASs that the existing actuation technologies cannot meet. To address the lack of actuation technologies for the PSAS application, this research proposes a unique actuation system that meets all the challenging design requirements of the PSAS. This new actuation system is based on the electromagnetic moving coil actuator (MCA) technology. The proposed system is conceptualized and modeled. The key parameters of the actuation system are defined following the conceptual design and modeling. Further, the geometry mapping optimization and the FEM analysis are conducted to determine the optimized values for the key design parameters. From the simulation results, the optimized actuator is shaped. Moreover, a proper control strategy is proposed for the motion of the actuator. Experiments are performed to find the empirical parameters of the actuator, to validate the proposed design, and to test the performance of the actuator. Experimental results show that the prototype of the actuation system meets the design requirements and is feasible for implementation in the SSIPTS. The main contribution of this thesis is to develop a highly efficient and reliable ultra fast bi-stable actuation system for the PSAS for the SSIPTS. As an ultra fast bistable actuation system, the designed actuation system has many advantages over other types of actuation systems: higher load capacity, smaller dimensions, and good controllability. These performance characteristics make the designed actuation system an excellent candidate in applications requiring fast transient response, high precision, and high load capacity such as electromagnetic valve actuators for engines, high speed pick and place, and precise positioning.

This Ph.D. thesis presents the design, modeling, optimization, prototyping, and experimental methodologies for a novel actuation system for the synchronized segmentally interchanging pulley transmission system (SSIPTS). The SSIPTS is an improved transmission which offers the combined benefits of existing transmission systems for the automotive, the power generation, and the heating, ventilation, and air conditioning (HVAC) industries. As a major subsystem of the SSIPTS, the Pulley Segment Actuation System (PSAS) plays a critical role in the SSIPTS operation and success. However, the overall design of the SSIPTS and its operation principle introduce very challenging and conflicting design requirements for PSASs that the existing actuation technologies cannot meet. To address the lack of actuation technologies for the PSAS application, this research proposes a unique actuation system that meets all the challenging design requirements of the PSAS. This new actuation system is based on the electromagnetic moving coil actuator (MCA) technology. The proposed system is conceptualized and modeled. The key parameters of the actuation system are defined following the conceptual design and modeling. Further, the geometry mapping optimization and the FEM analysis are conducted to determine the optimized values for the key design parameters. From the simulation results, the optimized actuator is shaped. Moreover, a proper control strategy is proposed for the motion of the actuator. Experiments are performed to find the empirical parameters of the actuator, to validate the proposed design, and to test the performance of the actuator. Experimental results show that the prototype of the actuation system meets the design requirements and is feasible for implementation in the SSIPTS. The main contribution of this thesis is to develop a highly efficient and reliable ultra fast bi-stable actuation system for the PSAS for the SSIPTS. As an ultra fast bistable actuation system, the designed actuation system has many advantages over other types of actuation systems: higher load capacity, smaller dimensions, and good controllability. These performance characteristics make the designed actuation system an excellent candidate in applications requiring fast transient response, high precision, and high load capacity such as electromagnetic valve actuators for engines, high speed pick and place, and precise positioning.

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Many applications such as automobiles, gyroscopes, machine tools, and transfer systems require orientation control of a rotating shaft. Demands for multi-degree of freedom (DOF) actuators in modern industries have motivated this research to develop a ball-joint-like, brushless, direct-drive spherical wheel motor (SWM) that offers a means to control the orientation of its rotating shaft. This thesis presents a general method for deriving a closed-form magnetic field solution for precise torque calculation. The method, referred here as distributed multi pole (DMP) modeling, inherits many advantages of the dipole model originally conceptualized in the context of physics, but provides an effective means to account for the shape and magnetization of the physical magnet. The DMP modeling method has been validated by comparing simulated fields and calculated forces against data obtained experimentally and numerically; the comparisons show excellent agreement. The DMP models provide a basis to develop a non-contact magnetic sensor for orientation sensing and control of a rotating shaft. Three controllers have been designed and experimentally implemented for the SWM; open-loop and PD with/without an observer. The OL control system, which decouples the spin from the shaft inclination, provides the fundamental design structure for the SWM and serves as a basis for designing feedback controllers with/without an observer. While the observer and controller designs have been developed in the context of a spherical wheel motor, these techniques along with the models and analysis tools developed in this research can be applied to design, analysis and control of most electromagnetic devices. We expect that the analytical method along with the orientation sensor and spherical wheel motor will have broad spectrum of applications.

The diploma thesis deals with an engineering design, a realization and a calibration of a apparatus for surface texturing of test samples. Microdents are produced by a diamond tool pressing. Electromagnetic linear actuator is used for pressing. Translation and rotation of the sample are secured by a couple of stepping motors. Thanks to this the apparatus can produce texture with well defined and easily controlled geometry. The diploma thesis contains a summary of surface texturing methods, designs of constructional variations, a electronic device of the apparatus and the calibration are also included.

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No description available.

<p>Achieving better NVH (noise, vibration, and harshness) comfort necessitates the use of active technologies when product targets are beyond the scope of traditional passive insulators, absorbers, and dampers. Therefore, a lot of effort is now being put in order to develop various active solutions for vibration control, where the development of actuators is one part. </p><p>Active hydraulic engine mounts have shown to be a promising actuator for vibration isolation with the benefits of the commonly used passive hydraulic engine mount in addition to the active ones. In this thesis, a benchmark of actuators for active vibration control has been carried out. Piezoelectric actuators and electromagnetic actuators are studied further and two methods to estimate parameters for electromagnetic actuators have been developed. A parameterized model of an active hydraulic engine mount valid for frequencies from zero to about 300 Hz, has also been developed. Good agreement with experimental data has been achieved.</p>

Achieving better NVH (noise, vibration, and harshness) comfort necessitates the use of active technologies when product targets are beyond the scope of traditional passive insulators, absorbers, and dampers. Therefore, a lot of effort is now being put in order to develop various active solutions for vibration control, where the development of actuators is one part. Active hydraulic engine mounts have shown to be a promising actuator for vibration isolation with the benefits of the commonly used passive hydraulic engine mount in addition to the active ones. In this thesis, a benchmark of actuators for active vibration control has been carried out. Piezoelectric actuators and electromagnetic actuators are studied further and two methods to estimate parameters for electromagnetic actuators have been developed. A parameterized model of an active hydraulic engine mount valid for frequencies from zero to about 300 Hz, has also been developed. Good agreement with experimental data has been achieved.