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A practical and non-invasive method of calculating the efficiency of electric motors could help reduce anthropogenic green house gas emissions by up to 6%. Such a method has been developed using quantitative thermography, however currently, the time required for its implementation is prohibitive. In this thesis, registration and segmentation techniques are applied to the thermograms of the above method, particularly thermograms used in the lumped capacitance method (LCM) and those used to find the average temperature of motors, reducing the time required to process thermograms. The processing of LCM thermograms was completely automated (±5% difference when compared to results obtained manually) while processing of motor thermograms required the location of the motor be provided manually the first time a motor is examined, but was completely automated for subsequent thermo- grams of the same motor (±0.9°C and ±0.6°C difference for non-occluded and occluded motors respectively compared to manual results). / NSERC Chair in Environmental Design Engineering

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This thesis begins with a literature review focusing on electric vehicle (EV) applications. Systems used for steering, braking and energy storage are investigated, with specific concentration on torque control in various DC and AC motors commonly used in EVs. A final solution for a low range personal transportation EV in the form of a wheelchair is proposed. The theme for this thesis is motion control, focusing on a two axis (or two wheel drive) brushless DC hub motor (BLDCHM) EV, with torque and direction control tracking a user reference. The operation principle for a BLDCHM is documented and the dynamic and electrical equations derived. Simulation results for motor response under different load and speed conditions are compared to practical measurements. Current and torque control loops are designed, implemented and tuned on a single-axis test-bed with an induction motor (IM) load coupled via a torque transducer. A Texas Instrument DSP development kit is used for the control algorithm bench testing. The final control algorithm is then duplicated and expanded in simulation to form a dynamic two axis system for an electric wheelchair. It incorporates both motor drive and regenerative capabilities. After demonstrating two axis controls for BLDCHMs, a control algorithm is designed simulated and compared to traditional systems. The final solution focuses specifically on an intuitive response to the driver input whilst maintaining direction tracking, even when there is a difference in smoothness of the individual terrains traversed by the left and right wheels. In addition the motor drives are equipped with controllers that ensure regenerative braking in order to recover as much energy as possible when the wheelchair is commanded to decelerate. / M. Sc. Eng. University of KwaZulu-Natal, Durban 2014.

One of the most common goals in manufacturing is to improve the quality and accuracy of the parts being fabricated without reducing productivity. Aiming at this goal, many different manufacturing processes have been developed. Among them, machining plays a major role in increasing product accuracy. As an important machining process, grinding is a vital step that can produce both fine finish and dimensional accuracy for applications in which the workpiece material is either hard or brittle. Currently, the ball screw is the most frequently used setup for grinding machine tool feed drive. However, the existence of transmission components induces wear, high friction, backlash, and also lower system stiffness; therefore, applications of conventional feed drives for high speed and high accuracy machining are very limited. As a promising technology, a linear motor feed drive discards the transmission system; therefore, it eliminates transmission induced error, such as backlash and pitch error, and avoids stiffness reduction as well. As a result, a linear motor drive can achieve both high speed and high accuracy performance. A linear motor feed drive will be subject to external disturbances such as friction, force ripple and machining force. Due to the lack of a transmission unit, the tracking behavior of a linear motor feed drive is prone to be affected by external disturbances and model parameter variations. Thus, in order to deliver high performance, a controller should be capable of achieving high accuracy in the presence of external disturbance and parameter uncertainty. This dissertation proposes a general robust motion control framework for the CNC design of a linear motor feed drive to achieve high speed/high precision as well as low speed/high precision. An application to the linear motor feed drives in grinding machines was carried out. One of the developed algorithms is the HSMC, which combines the merits of a reaching law based sliding mode control and a modified disturbance observer for precision tracking to address the practical issues of friction, force ripple, and grinding force disturbances. Another algorithm presented is ASMC, which combines the reaching law based sliding mode control with adaptive disturbance estimation to achieve an adaptive robust motion control.

Thesis (Ph.D.)--University of Western Sydney, Nepean, 1995. / Includes bibliography.

Thesis (M.Sc (Hons)) -- University of Western Sydney, Nepean, 2000. / "Submitted for the degree of Master of Engineering (Hons), School of Mechatronic, Computer & Electrical Engineering, University of Western Sydney, Nepean" Includes bibliographical references (leaves 107-114).

Thesis (M.S.)--Ohio University, November, 1996. / Title from PDF t.p.

Thesis (Ph.D.)--University of Wollongong, 2008. / Typescript. Includes bibliographical references: page 150-155.