Inductive power transfer for on-body sensors defining a design space for safe, wirelessly powered on-body health sensors

Pervasive Health: 9th International Conference on Pervasive Computing Technologies for Healthcare, 20-23 May 2015, Istanbul, TurkeyDesigners of on-body health sensing devices face a difficult choice. They must either minimise the power consumption of devices, which in reality means reducing the sensing capabilities, or build devices that require regular battery changes or recharging. Both options limit the effectiveness of devices. Here we investigate an alternative. This paper presents a method of designing safe, wireless, inductive power transfer into on-body sensor products. This approach can produce sensing devices that can be worn for longer durations without the need for human intervention, whilst also having greater sensing and data capture capabilities. The paper addresses significant challenges in achieving this aim, in particular: device safety, sufficient power transfer, and human factors regarding device geometry. We show how to develop a device that meets stringent international safety guidelines for electromagnetic energy on the body and describe a design space that allows designers to make trade-offs that balance power transfer with other constraints, e.g. size and bulk, that affect the wearability of devices. Finally we describe a rapid experimental method to investigate the optimal placement of on-body devices and the actual versus theoretical power transfer for on-body, inductively powered devices. EPSR

Inflashoe:A Shape Changing Shoe to Control Underfoot Pressure

We present Inflashoe, an interactive shoe that uses a pneumatic system to change the inflation level within the sole. This allows the shoe to adapt its shape to different surfaces and users' foot morphology, or to alter users' gait. Inflashoe can not only change the overall inflation, but can also individually control the inflation of the back and front of the insole, creating different levels of elevation across the shoe when needed. In this paper we describe our prototype implementation and present the results of a preliminary evaluation study. We show that 85% of participants found Inflashoe to be equal to or more comfortable than their ordinary shoes, and that nearly 60% of them would prefer comfort to style. In the light of the results, we then discuss the potential applications of Inflashoe, in particular targeting specific kinds of pain or injury

Integrating electronic components into deformable objects based on user interaction data

A key challenge when designing deformable user interfaces is the integration of rigid electronic components with the soft deformable device. In this paper, we propose to place electronic components based on how the user is interacting with the device, i.e., in which way the device is being deformed when the user performs gestures. To identify optimum locations for placing electronic components, we developed a design tool that takes as input a 3D model of the deformable device and a set of captured user gestures. It then visualizes the stress distribution resulting from the gestures applied to the deformable device and suggests where not to place components because the location is highly deformed when users interact (e.g., a rigid battery that would constraint interaction); or alternatively where to place components to sense deformation more accurately (e.g., a bend sensor to detect a specific gesture) and efficiently (e.g., an energy harvesting component). We evaluated our approach by collecting interaction data from 12 users across three deformable devices (a watch, a camera, and a mouse) and applied the resulting stress distributions to the placement of selected electronic components

Influence of Exposure Guidelines on the Design of On-Body Inductive Power Transfer

IEEE Wireless Power Transfer Conference, Boulder, Colorado, USA,13-15 May, 2015Designers of on-body health sensing devices with inductive power transfer (IPT) face a number of trade-offs. Safe exposure limits should be maintained, and protective housing and padding are generally needed; however, these impose compromises on the power-transfer-system design. This paper analyses these trade-offs and proposes a design route to achieving high power transfer in the presence of field restrictions and separations for padding or housing materials. An IPT system using a Class D coil-driver and switched-mode power-conditioning is designed to provide regulated d.c. and energy storage. Compliance with ICNIRP 1998 guidelines is demonstrated, at a power level that is sufficient to power typical on-body medical sensing devices.UK Engineering and Physical Sciences Research Council (EPSRC

A Norovirus outbreak associated with Oyster consumption in NSW and implications for public health.

Norovirus is a common cause of gastroenteritis outbreaks associated with raw shellfish consumption. In Australia there have been several reports of norovirus outbreaks associated with oysters despite the application of regulatory measures recommended by Food Standards Australia New Zealand. This study describes an outbreak of norovirus gastroenteritis following the consumption of New South Wales oysters. In September 2007, OzFoodNet conducted a cohort study of a gastroenteritis outbreak amongst people that had dined at a Port Macquarie restaurant. Illness was strongly associated with oyster consumption, with all cases having eaten oysters from the same lease (RR undefined, p < 0.0001). Norovirus was detected in a faecal specimen. Although no pathogen was identified during the environmental investigation, the source oyster lease had been closed just prior to harvesting due to sewage contamination. Australian quality assurance programs do not routinely test oysters for viral contamination that pose a risk to human health. It is recommended that the feasibility of testing oysters for norovirus, particularly after known faecal contamination of oyster leases, be assessed