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Floating platforms are complex structures used in deep water and high wind speeds. However, a methodology should be defined to have a stable offshore structure and not fail dynamically in severe environmental conditions. This paper aims to provide a method for estimating failure load or ultimate load on the anchors of floating systems in integrating wind and tidal turbines in New Zealand. Using either wind or tidal turbines in areas with harsh water currents is not cost-effective. Also, tidal energy, as a predictable source of energy, can be an alternative for wind energy when cut-in speed is not enough to generate wind power. The most expensive component after the turbine is the foundation. Using the same foundation for wind and tidal turbines may reduce the cost of electricity. Different environment scenarios as load cases have been set up to test the proposed system's performance, capacity and efficiency. Available tidal records from the national institute of Water and Atmospheric Research (NIWA) have been used to find the region suitable for offshore energy generation and to conduct simulation model runs. Based on the scenarios, Terawhiti in Cook Strait with 110 m water height was found as the optimized site. It can be seen that the proposed floating hybrid system is stable in the presence of severe environmental conditions of wind and wave loadings in Cook Strait and gives a procedure for sizing suction caisson anchors.

Wearables robots have gained attention for the rehabilitation of people with physical disabilities. However, the current technology relies on heavy and bulky actuation components, making it hard to use outside clinical settings. Artificial muscles based on smart materials are trending for soft wearable rehabilitation robots as they present advantages of compliance, are lightweight, and do not require external components. Nevertheless, they present challenges that remain unresolved, preventing widespread adoption. This work reviews the current state of soft wearable rehabilitation robots with artificial muscles based on smart materials (AMSMs). A literature search is conducted utilizing Web of Science and Scopus. Based on the inclusion–exclusion criteria, 15 devices are found using four different smart materials. This study attempts to provide an insight into the distinct biomechanical requirements, the use of smart materials, their limitations, their designs, and possible future research directions, which can provide helpful guidance on the implementation and development of advanced soft wearable rehabilitation robots with AMSMs.

Abstract Children with physical disabilities often have limited performance in daily activities, hindering their physical development, social development and mental health. Therefore, rehabilitation is essential to mitigate the adverse effects of the different causes of physical disabilities and improve independence and quality of life. In the last decade, robotic rehabilitation has shown the potential to augment traditional physical rehabilitation. However, to date, most robotic rehabilitation devices are designed for adult patients who differ in their needs compared to paediatric patients, limiting the devices’ potential because the paediatric patients’ needs are not adequately considered. With this in mind, the current work reviews the existing literature on robotic rehabilitation for children with physical disabilities, intending to summarise how the rehabilitation robots could fulfil children’s needs and inspire researchers to develop new devices. A literature search was conducted utilising the Web of Science, PubMed and Scopus databases. Based on the inclusion–exclusion criteria, 206 publications were included, and 58 robotic devices used by children with a physical disability were identified. Different design factors and the treated conditions using robotic technology were compared. Through the analyses, it was identified that weight, safety, operability and motivation were crucial factors to the successful design of devices for children. The majority of the current devices were used for lower limb rehabilitation. Neurological disorders, in particular cerebral palsy, were the most common conditions for which devices were designed. By far, the most common actuator was the electric motor. Usually, the devices present more than one training strategy being the assistive strategy the most used. The admittance/impedance method is the most popular to interface the robot with the children. Currently, there is a trend on developing exoskeletons, as they can assist children with daily life activities outside of the rehabilitation setting, propitiating a wider adoption of the technology. With this shift in focus, it appears likely that new technologies to actuate the system (e.g. serial elastic actuators) and to detect the intention (e.g. physiological signals) of children as they go about their daily activities will be required.

This paper introduces the typical wind patterns in New Zealand recording by the National Institute of Water and Atmospheric Research (NIWA) and evaluates the optimized sites among them with higher amount of power generation. A comprehensive simulation model has been set up, using several available commercial software packages to test the performance, capacity and efficiency of the results. Available wind records have been used from NASA to conduct simulation model runs of them. Global Wind Atlas is used for showing wind patterns and WRPLOT software plots wind class of sites. Homer Pro software used to propose a microgrid design for each site and calculate power. Generation of electricity from wind turbines depends on the wind speeds and cut-in speed of the wind turbines. In other words, to reach maximum efficiency from wind power, the first step is to analyse the wind speeds of the site where turbine will be located and then estimate the generated power from that turbine. To do it, it is necessary to find the range of wind speeds and the wind directions with demonstrating wind rose and the percentage of year a turbine is working in more than cut-in speed. Based on current wind patterns, Dunedin and Bluff sites found the areas with maximum power generation.

This paper proposes and evaluates an optimized system of tidal turbines as a renewable energy generating unit in New Zealand. A comprehensive simulation model has been set up, using several available commercial software packages to test the performance, capacity and efficiency of the proposed system. Available tidal records have been used to find four regions that are suitable for tidal energy generation and conduct simulation model runs at one of them, Foveaux, to provide the electricity for the isolated area of Stewart Island. Generation of electricity with tidal turbines depends on the water currents and cut-in speed of the tidal turbines. In other words, to reach maximum efficiency from tidal power, the first step is to analyse the water currents of the site where turbine will be located and then estimate the generated power from that turbine. To do it, it is necessary to find the range of water currents and the tidal directions with demonstrating tidal rose and also find how to get maximum power by choosing a proper tidal turbine. Based on tidal flows of the Foveaux straight, two tidal turbines (Schottel 54 kW and 70 kW) with different cut-in speeds are selected. The results indicate that choosing Schottel 54 kW with 0.2 m/s less cut-in speed in comparison to Schottel 70 kW can generate 4.7 times more power.

The fast expansion of ICT (information and communications technology) has provided rich sources of data for the analysis, modeling, and interpretation of human mobility patterns. Many researchers have already introduced behavior-aware protocols for a better understanding of architecture and realistic modeling of behavioral characteristics, similarities, and aggregation of mobile users. We are introducing the similarity analytical framework for the mobile encountering analysis to allow for more direct integration between the physical world and cyber-based systems. In this research, we propose a method for finding the similarity behavior of users’ mobility patterns based on location and time. This research was conducted to develop a technique for producing co-occurrence matrices of users based on their similar behaviors to determine their encounters. Our approach, named SAA (similarity analysis approach), makes use of the device info i.e., IP (internet protocol) and MAC (media access control) address, providing an in-depth analysis of similarity behaviors on a daily basis. We analyzed the similarity distributions of users on different days of the week for different locations based on their real movements. The results show similar characteristics of users with common mobility behaviors based on location and time to showcase the efficacy. The results show that the proposed SAA approach is 33% more accurate in terms of recognizing the user’s similarity as compared to the existing similarity approach.

This paper evaluates the feasibility of using wind power for power supply to coastal communities isolated from the main supply grid. The case study is Stewart Island, where the cost of electricity provided by a central diesel power station is higher than the grid network in New Zealand. The Princeton Ocean Model (POM) conducted by MetOcean Solutions Limited (MSL) is used to find Foveaux as an optimized site for generating wind power. Global Wind Atlas is used to plot the wind rose of current wind patterns in New Zealand. In the next step, wind speed data from each site are imported from the NASA database to WRPLOT view software and Homer Pro to find wind frequency distribution and output power in the area. The maximum annual power can be seen in WSW (32,299 kW hours/year), SW (20,111 kW hours/year) and W (15,622 kW hour/year) directions, respectively.

This paper proposes and evaluates an optimized system of offshore wind turbines operating as a renewable energy generating unit in New Zealand. A comprehensive simulation model has been set up, using several available commercial software packages to test performance, capacity and efficiency of the proposed system. Available wind records have been used to select three coastal regions which are suitable for wind energy generation and conduct simulation model runs at three locations. Findings so far have been firstly that horizontal axis wind turbines are the most suitable for offshore installation; secondly that a direct current microgrid appears suitable for linking to the onshore electricity supply network; thirdly, many coastal sites can be ruled out because generating capacity is too low or because site factors preclude installation; and fourthly there are some sites where simulation results indicate good potential for offshore wind energy and other site factors do not preclude development. Evaluation of the economic feasibility and returns is now in progress.

In this study, the performance of different wind turbines is compared using Qblade software. Typically wind turbines are categorized as Horizontal Axis Wind Turbine (HAWT), and Vertical axis wind turbine (VAWT) which in this paper Darrieus type as a VAWT is discussed with HAWT. The airfoil selected for this study is NACA 0012, and from simulations, it can be seen in which wind speed range, each type has higher efficiency. Then, the parameters involved in their performance is discussed, and suggestions are made on how to modify them to have a higher output power. Qblade contains the XFOIL airfoil analysis functionalities which make a software a single tool which comprises all functionality needed for the design and simulation of vertical and horizontal axis wind turbines. The benefits of the proper airfoil design optimal are increasing the efficiency of wind turbines and maximization of the power produced.

This paper evaluates the feasibility of using a hybrid system consisting of wind and tidal turbines connected to a microgrid for power supply to coastal communities that are isolated from a main supply grid. The case study is Stewart Island, where the cost of electricity, provided by a central diesel power station, is higher than the grid network in New Zealand. Local residents believe that reducing the consumption of diesel and having a renewable source of electricity generation are two of the island’s highest priorities. Merging a tidal energy source (predictable) with wind (unpredictable) and diesel (back-up), through a microgrid, may be a way to increase reliability and decrease the cost of generation. Several off-grid configurations are simulated using HOMER and WRPLOT software. Using two wind and four tidal turbines, plus one diesel generator for back-up, is the best design in terms of lower greenhouse gas emissions, higher renewable fraction, and reduced net present cost.