The nonstationary nature of power-quality (PQ) waveforms requires a tool that can accurately analyze and visually identify the instants of transitions. One of the recently reported tools available to analyze nonstationary complex waveforms with a very good time resolution is the Hilbert Huang Transform (HHT). However, HHT has difficulty in resolving waveforms containing components with close frequencies with a ratio of less than two, and similar to other waveform classification techniques, it has difficulty in resolving the instants of sudden changes in the waveform. To overcome the problem with components containing close frequencies, a novel Iterative Hilbert Huang transform (IHHT) is proposed in this paper. To overcome the problem in identifying instants of sudden changes in the waveform, a new method using the Symbolic Aggregate ApproXimation (SAX) method is proposed. SAX converts the signal into symbols that can be utilized by a pattern detector algorithm to identify the boundaries of the stationary signals within a nonstationary signal. Results from IHHT and SAX method to analyze and visually identify simulated and measured nonstationary PQ waveforms will be provided and discussed. The proposed method is particularly useful when investigating the behavior of the harmonic components of a particular PQ waveform of interest in a given interval of time, following a data-mining search of a large database of PQ events. It can be used to both identify, and later isolate unique signatures within a provider's distribution system.

A survey of the adaptive controllers deployed to address major inherent control issues in robotic teleoperation systems is carried out. The study in particular explores the application of adaptive controllers in dealing with master and slave model uncertainties, operator and environment force model uncertainties, unknown external disturbances, and communication delay. The reviewed literature is structured according to the objectives envisaged for the adaptive controllers. Meanwhile, some adaptive methods deployed in human-robot interaction, where robots collaborate with people and actively support them, and local robot control, where robot manipulators are controlled at the same location as the operator, are also considered in the review as they can be used in teleoperation with some minor adjustment. A comparison of the strengths, deficiencies, and requirement of methods in each category is carried out. The study indicates that the majority of the proposed methods either require additional hardware such as sensors, or assume an accurate model of the system under study. The possible future research directions are outlined based on the gaps identified in the survey.

This survey reviews motion capture technologies and the current challenges associated with their application in robotic systems. Various sensor systems used in current literature are introduced and evaluated based on the relative strengths and weaknesses. Some research problems pursued with these sensors in robotics are reviewed and application areas are discussed. Significant methodologies in analysing the sensor data are discussed and evaluated based on the perceived benefits and limitations. Finally, results from experimentation with an inertial motion capture system are shown based on clustering and segmentation techniques.

Purpose – The purpose of this paper is to provide a review of various motion capture technologies and discuss the methods for handling the captured data in applications related to robotics. Design/methodology/approach – The approach taken in the paper is to compare the features and limitations of motion trackers in common use. After introducing the technology, a summary is given of robotic-related work undertaken with the sensors and the strengths of different approaches in handling the data are discussed. Each comparison is presented in a table. Results from the author's experimentation with an inertial motion capture system are discussed based on clustering and segmentation techniques. Findings – The trend in methodology is towards stochastic machine learning techniques such as hidden Markov model or Gaussian mixture model, their extensions in hierarchical forms and non-linear dimension reduction. The resulting empirical models tend to handle uncertainty well and are suitable for incrementally updating models. The challenges in human-robot interaction today include expanding upon generalising motions to understand motion planning and decisions and build ultimately context aware systems. Originality/value – Reviews including descriptions of motion trackers and recent methodologies used in analyzing the data they capture are not very common. Some exist, as has been pointed out in the paper, but this review concentrates more on applications in the robotics field. There is value in regularly surveying the research areas considered in this paper due to the rapid progress in sensors and especially data modeling.

The laboratory plays an important role in teaching engineering skills. An Electrical Engineering department at an Australian University implemented a reform to monitor and improve student satisfaction with the teaching laboratories. A Laboratory Manager was employed to oversee the quality of 27 courses containing instructional laboratories. Student satisfaction surveys were carried out on all relevant laboratories every year, and the data were used for continuous improvement. This paper will investigate the reforms that were implemented and outline a number of the improvements made. It also examines the program's overall impact on: (1) overall satisfaction; (2) laboratory notes; (3) learning experiences; (4) computer facilities; (5) engineering equipment; and (6) condition of the laboratory. Student satisfaction with the laboratories increased by 32% between 2007 and 2013. The results show that the laboratory notes (activity and clarity) and the quality of the equipment used are among the most influential factors on student satisfaction. In particular, it is important to have notes or resources that explain in some detail how to use and troubleshoot equipment and software used in the laboratory.