No description available.

No description available.

Amputation is a life-changing event that results in a drastic reduction in quality of life including extreme loss of function and severe mental, emotional and physical pain. In order to mitigate these negative outcomes, there is great interest in the design of ‘advanced/robotic’ prosthetics that cosmetically and functionally mimic the lost limb. While the robotics side of advanced prosthetics has seen many advances recently, they still provide only a fraction of the natural limbs’ functionality. At the heart of the issue is the interface between the robotic limb and the individual that needs significant development. Amputees retain significant function in their nerves post-amputation, which offers a unique opportunity to interface with the peripheral nerve. Here we evaluate a relatively new approach to peripheral nerve interfacing by using microchannels, which hold the intrinsic ability to record larger neural signals from nerves than previously developed peripheral nerve interfaces. We first demonstrate that microchannel scaffolds are well suited for chronic integration with amputated nerves and promote highly organized nerve regeneration. We then demonstrate the ability to record neural signals, specifically action potentials, using microchannels permanently integrated with electrodes after chronic implantation in a terminal study. Together these studies suggest that microchannels are well suited for chronic implantation and stable peripheral nerve interfacing. As a next step toward clinical translation, we developed fully-integrated high electrode count microchannel interfacing technology capable of functioning while implanted in awake and freely moving animal models as needed for pre-clinical evaluation. Importantly, fabrication techniques were developed that apply to a broad range of flexible devices/sensors benefiting from flexible interconnects, surface mount device (SMD) integration, and/or operation in aqueous environments. Examples include diabetic glucose sensors, flexible skin based health monitors, and the burgeoning flexible wearable technology industry. Finally, we successfully utilized the fully integrated microchannel interfaces to record action potentials in the challenging awake and freely moving animal model validating the microchannel approach for peripheral nerve interfacing. In the end, the findings of these studies help direct and give significant credence to future technology development enabling eventual clinical application of microchannels for peripheral nerve interfacing.

Individuals with functional blindness must often utilise assistive aids to enable them to complete tasks of daily living. One of these tasks, locomotion, poses considerable risk. The long white cane is often used to perform haptic exploration, but cannot detect obstacles that are not ground-based. Although devices have been developed to provide information above waist height, these do not provide auditory interfaces that are easy to learn. Development of such devices should adapt to the user, not require adaptation by the user. Can obstacle avoidance be achieved through direct perception? This research presents an auditory interface that has been designed with the user as the primary focus. An analysis of the tasks required has been taken into account resulting in an interface that audifies ultrasound. Audification provides intuitive information to the user to enable perceptive response to environmental obstacles. A device was developed that provides Doppler shift signals that are audible as a result of intentional aliasing. This system provides acoustic flow that is evident upon initiation of travel and has been shown to be effective in perceiving apertures and avoiding environmental obstacles. The orientation of receivers on this device was also examined, resulting in better distance perception and centreline accuracy when oriented outward as compared to forward. The design of this novel user interface for visually impaired individuals has also provided a tool that can be used to evaluate direct perception and acoustic flow in a manner that has never been studied before.

Individuals with functional blindness must often utilise assistive aids to enable them to complete tasks of daily living. One of these tasks, locomotion, poses considerable risk. The long white cane is often used to perform haptic exploration, but cannot detect obstacles that are not ground-based. Although devices have been developed to provide information above waist height, these do not provide auditory interfaces that are easy to learn. Development of such devices should adapt to the user, not require adaptation by the user. Can obstacle avoidance be achieved through direct perception? This research presents an auditory interface that has been designed with the user as the primary focus. An analysis of the tasks required has been taken into account resulting in an interface that audifies ultrasound. Audification provides intuitive information to the user to enable perceptive response to environmental obstacles. A device was developed that provides Doppler shift signals that are audible as a result of intentional aliasing. This system provides acoustic flow that is evident upon initiation of travel and has been shown to be effective in perceiving apertures and avoiding environmental obstacles. The orientation of receivers on this device was also examined, resulting in better distance perception and centreline accuracy when oriented outward as compared to forward. The design of this novel user interface for visually impaired individuals has also provided a tool that can be used to evaluate direct perception and acoustic flow in a manner that has never been studied before.

Individuals with functional blindness must often utilise assistive aids to enable them to complete tasks of daily living. One of these tasks, locomotion, poses considerable risk. The long white cane is often used to perform haptic exploration, but cannot detect obstacles that are not ground-based. Although devices have been developed to provide information above waist height, these do not provide auditory interfaces that are easy to learn. Development of such devices should adapt to the user, not require adaptation by the user. Can obstacle avoidance be achieved through direct perception? This research presents an auditory interface that has been designed with the user as the primary focus. An analysis of the tasks required has been taken into account resulting in an interface that audifies ultrasound. Audification provides intuitive information to the user to enable perceptive response to environmental obstacles. A device was developed that provides Doppler shift signals that are audible as a result of intentional aliasing. This system provides acoustic flow that is evident upon initiation of travel and has been shown to be effective in perceiving apertures and avoiding environmental obstacles. The orientation of receivers on this device was also examined, resulting in better distance perception and centreline accuracy when oriented outward as compared to forward. The design of this novel user interface for visually impaired individuals has also provided a tool that can be used to evaluate direct perception and acoustic flow in a manner that has never been studied before.

Individuals with functional blindness must often utilise assistive aids to enable them to complete tasks of daily living. One of these tasks, locomotion, poses considerable risk. The long white cane is often used to perform haptic exploration, but cannot detect obstacles that are not ground-based. Although devices have been developed to provide information above waist height, these do not provide auditory interfaces that are easy to learn. Development of such devices should adapt to the user, not require adaptation by the user. Can obstacle avoidance be achieved through direct perception? This research presents an auditory interface that has been designed with the user as the primary focus. An analysis of the tasks required has been taken into account resulting in an interface that audifies ultrasound. Audification provides intuitive information to the user to enable perceptive response to environmental obstacles. A device was developed that provides Doppler shift signals that are audible as a result of intentional aliasing. This system provides acoustic flow that is evident upon initiation of travel and has been shown to be effective in perceiving apertures and avoiding environmental obstacles. The orientation of receivers on this device was also examined, resulting in better distance perception and centreline accuracy when oriented outward as compared to forward. The design of this novel user interface for visually impaired individuals has also provided a tool that can be used to evaluate direct perception and acoustic flow in a manner that has never been studied before.

Brain-computer music interfacing (BCMI) presents a novel approach to music making, as it requires only the brainwaves of a user to control musical parameters. This presents immediate benefits for users with motor disabilities that may otherwise prevent them from engaging in traditional musical activities such as composition, performance or collaboration with other musicians. BCMI systems with active control, where a user can make cognitive choices that are detected within brain signals, provide a platform for developing new approaches towards accomplishing these activities. BCMI systems that use passive control present an interesting alternate to active control, where control over music is accomplished by harnessing brainwave patterns that are associated with subconscious mental states. Recent developments in brainwave measuring technologies, in particular electroencephalography (EEG), have made brainwave interaction with computer systems more affordable and accessible and the time is ripe for research into the potential such technologies can offer for creative applications for users of all abilities. This thesis presents an account of BCMI development that investigates methods of active, passive and hybrid (multiple control methods) control that include control over electronic music, acoustic instrumental music, multi-brain systems and combining methods of brainwave control. In practice there are many obstacles associated with detecting useful brainwave signals, in particular when scaling systems otherwise designed for medical studies for use outside of laboratory settings. Two key areas are addressed throughout this thesis. Firstly, improving the accuracy of meaningful brain signal detection in BCMI, and secondly, exploring the creativity available in user control through ways in which brainwaves can be mapped to musical features. Six BCMIs are presented in this thesis, each with the objective of exploring a unique aspect of user control. Four of these systems are designed for live BCMI concert performance, one evaluates a proof-of-concept through end-user testing and one is designed as a musical composition tool. The thesis begins by exploring the field of brainwave detection and control and identifies the steady-state visually evoked potential (SSVEP) method of eliciting brainwave control as a suitable technique for use in BCMI. In an attempt to improve signal accuracy of the SSVEP technique a new modular hardware unit is presented that provides accurate SSVEP stimuli, suitable for live music performance. Experimental data confirms the performance of the unit in tests across three different EEG hardware platforms. Results across 11 users indicate that a mean accuracy of 96% and an average response time of 3.88 seconds are attainable with the system. These results contribute to the development of the BCMI for Activating Memory, a multi-user system. Once a stable SSVEP platform is developed, control is extended through the integration of two more brainwave control techniques: affective (emotional) state detection and motor imagery response. In order to ascertain the suitability of the former an experiment confirms the accuracy of EEG when measuring affective states in response to music in a pilot study. This thesis demonstrates how a range of brainwave detection methods can be used for creative control in musical applications. Video and audio excerpts of BCMI pieces are also included in the Appendices.

No description available.

A terrestrial robotic electrophysiology platform has been developed that can hold a moth (<italic>Manduca sexta</italic>), record signals from its brain or muscles, and use these signals to control the rotation of the robot. All signal processing (electrophysiology, spike detection, and robotic control) was performed onboard the robot with custom designed electronic circuits. Wireless telemetry allowed remote communication with the robot. In this study, we interfaced directionally-sensitive visual neurons and pleurodorsal steering muscles of the mesothorax with the robot and used the spike rate of these signals to control its rotation, thereby emulating the classical optomotor response known from studies of the fly visual system. The interfacing of insect and machine can contribute to our understanding of the neurobiological processes underlying behavior and also suggest promising advancements in biosensors and human brain-machine interfaces.