Biomedical subjects

G J Suaning

Publications and source records attributed to G J Suaning.

6 recordsLinked to original sources

PubMed2006

Bank note recognition for the vision impaired.

Blind Australians find great difficulty in recognising bank notes. Each note has the same feel, with no Braille markings, irregular edges or other tangible features. In Australia, there is only one device available that can assist blind people recognise their notes. Internationally, there are devices available; however they are expensive, complex and have not been developed to cater for Australian currency. This paper discusses a new device, the MoneyTalker that takes advantage of the largely different colours and patterns on each Australian bank note and recognises the notes electronically, using the reflection and transmission properties of light. Different coloured lights are transmitted through the inserted note and the corresponding sensors detect distinct ranges of values depending on the colour of the note. Various classification algorithms were studied and the final algorithm was chosen based on accuracy and speed of recognition. The MoneyTalker has shown an accuracy of more than 99%. A blind subject has tested the device and believes that it is usable, compact and affordable. Based on the devices that are available currently in Australia, the MoneyTalker is an effective alternative in terms of accuracy and usability.

Algorithms↗

PubMed2005

Fabrication of implantable microelectrode arrays by laser cutting of silicone rubber and platinum foil.

A new method for fabrication of microelectrode arrays comprised of traditional implant materials is presented. The main construction principle is the use of spun-on medical grade silicone rubber as insulating substrate material and platinum foil as conductor (tracks, pads and electrodes). The silicone rubber and the platinum foil are patterned by laser cutting using an Nd:YAG laser and a microcontroller-driven, stepper-motor operated x-y table. The method does not require expensive clean room facilities and offers an extremely short design-to-prototype time of below 1 day. First prototypes demonstrate a minimal achievable feature size of about 30 microm.

Biocompatible Materials↗

PubMed2005

Visual acuity measurement of prosthetic vision: a virtual-reality simulation study.

A virtual-reality simulation tested prosthetic visual acuity for both rectangular and hexagonal phosphene grids. Thirteen normally sighted, untrained subjects were required to identify the Landolt C optotype over ten sessions. Overall performance, performance by filter setting (image analysis), and performance by size and orientation of the Landolt C optotype are reported. The results indicated that the hexagonal grid had a slight (4.1%) but statistically significant (p < 0.0001) performance advantage over the rectangular grid for correct identification of the testing symbol. It was also observed that both the phosphene grids had distinct performance profiles relating to their respective spatial orientation. Over the course of the ten sessions, learning afforded subjects an averaged improved performance of 10%.

Artificial Intelligence↗

PubMed2001

CMOS neurostimulation ASIC with 100 channels, scaleable output, and bidirectional radio-frequency telemetry.

100-channel neurostimulation circuit comprising a complementary metal oxide semiconductor (CMOS), application-specific integrated circuit (ASIC) has been designed, constructed and tested. The ASIC forms a significant milestone and an integral component of a 100-electrode neurostimulation system being developed by the authors. The system comprises an externally worn transmitter and a body implantable stimulator. The purpose of the system is to communicate both data and power across tissue via radio-frequency (RF) telemetry such that externally programmable, constant current, charge balanced, biphasic stimuli may be delivered to neural tissue at 100 unique sites. An intrinsic reverse telemetry feature of the ASIC has been designed such that information pertaining to the device function, reconstruction of the stimulation voltage waveform, and the measurement of impedance may be obtained through noninvasive means. To compensate for the paucity of data pertaining to the stimulation thresholds necessary in evoking a physiological response, the ASIC has been designed with scaleable current output. The ASIC has been designed primarily as a treatment of degenerative disorders of the retina whereby the 100 channels are to be utilized in the delivery of a pattern of stimuli of varying intensity and or duty cycle to the surviving neural tissue of the retina. However, it is conceivable that other fields of neurostimulation such as cochlear prosthetics and functional electronic stimulation may benefit from the employment of the system.

Electric Impedance↗

PubMed1998

The bionic eye (electronic visual prosthesis): a review.

The concept of a visual prosthesis for the blind or partially sighted is not a new one. Indeed, for more than three decades this technology based treatment for blindness has appeared imminent. Despite the concerted efforts of numerous physicians, scientists and engineers, the successful application of a useful visual prosthesis remains elusive. The present review will endeavour to describe past efforts, investigate the present state of the art and indicate the obstacles that must be overcome in order to bring an electronic visual prosthesis to fruition.

Bionics↗

PubMed1998

Monte Carlo simulation of tuning capacitor selection in a cochlear implant.

The principles of Monte Carlo simulation are applied to critical manufacturing process in the construction of cochlear implants. In this application, the tuning of the implant's radio frequency (RF) communication system is dependent upon a "select on test" tuning capacitance. The aim is to accurately predict the usage of capacitors of a given size in future production of cochlear implants using Monte-Carlo simulation. The predicted quantities may then be purchased from a supplier to satisfy the requirements of high volume manufacturing without maintaining unnecessary and expensive stock levels of infrequently or never used capacitors. Simulations indicate that for large production runs, prediction of the necessary quantities of particular tuning capacitor sizes may enable the implant manufacturer to reduce their capacitor stock levels by as much as 82 percent. This significant reduction is in comparison to maintaining a uniform stock level of all sizes of capacitors, assuming random probability of requiring each size of tuning capacitor.

Cochlear Implants↗