Biomechanics

In this thesis, an augmented reality device was coupled with motion sensor units to function as a system of cooperative technologies for usage within exercise science and neurorehabilitation. Specifically, in a subfield of exercise science called biomechanics, the assessment and analysis of movements are critical to the evaluation and prescription of improvements for physical function in both daily and sport-specific activities. Furthermore, the systematic combination of these technologies provided potential end-users with a modality to perform exercise within, and correlated feedback based upon the end-user’s exercise performance. Data collection specific to biomechanics can provide both the end-user and their evaluators with critical feedback that can be used to modify movement efficiency, improve exercise capacity, and evaluate exercise performance. By coordinating both technologies and completing movement-based experiments, the systems were successfully integrated.

The red lionfish, Pterois volitans, has arguably become the most successful marine invasive species to date. Yet, despite the invasion success of P. volitans, little is known about the morphology, physiology, and ecology of this species in their native and invaded habitats. The majority of recent studies have focused on the migration of P. volitans into new regions, digestion, and bacterial infections. Knowledge is lacking on the body plan of the invasive lionfish, specifically the numerous venomous spines that are protruding outward, making the body less streamlined. In this study we quantified the mechanical properties (bending and puncture) of the venomous spines of P. volitans, and related these properties to the cross-sectional morphology. We also documented variation in the cross-sectional morphology of spines from other lionfish species in their native regions. Lastly, we documented the dorsal spine joint morphology of the first three dorsal spines and the in situ range of motion as tissues were removed. We found that the long, numerous dorsal spines absorb more energy but are less stiff than the pelvic and anal spines. In addition, we found that the anal and pelvic spines are more effective at puncturing buccal skin from sharks and grouper. We found that the removal of connective tissue significantly changes lateral movement (abduction) for the first three dorsal spines. The removal of the fin sheath significantly alters forward movement (extension) for the first two dorsal spines. From morphology, mechanical property, and range of motion data for P. volitans, we propose that the numerous long dorsal spines are primarily used for intimidation, and are not as effective defense structures as the pelvic and anal spines. Having a substantial amount of intimidating, venomous spines may allow for the lionfish to conserve energy for other highly metabolically costly activities other than warding off predators, such as digestion and reproduction. Future studies could focus on the amount of venom in each spine, how long it takes for the venom to be made and replaced, how the venomous spines affect hydrodynamic flow, and in vivo range of motion during swimming and striking.

The design and construction of a tri-cable, planar robotic device for use in neurophysical rehabilitation is presented. The criteria for this system are based primarily on marketability factors, rather than ideal models or mathematical outcomes. The device is designed to be low cost and sufficiently safe for a somewhat disabled individual to use unsupervised at home, as well as in a therapist's office. The key features are the use of a barrier that inhibits the user from coming into contact with the cables as well as a "break-away" joystick that the user utilizes to perform the rehabilitation tasks. In addition, this device is portable, aesthetically acceptable and easy to operate. Other uses of this system include sports therapy, virtual reality and teleoperation of remote devices.

The design and construction of a tri-cable, planar robotic device for use in neurophysical rehabilitation is presented. The criteria for this system are based primarily on marketability factors, rather than ideal models or mathematical outcomes. The device is designed to be low cost and sufficiently safe for a somewhat disabled individual to use unsupervised at home, as well as in a therapist's office. The key features are the use of a barrier that inhibits the user from coming into contact with the cables as well as a "break-away" joystick that the user utilizes to perform the rehabilitation tasks. In addition, this device is portable, aesthetically acceptable and easy to operate. Other uses of this system include sports therapy, virtual reality and teleoperation of remote devices.

A robotic ribbon fin with twelve independent fin rays, elastic fin membrane, and a body
of adjustable height was developed for this thesis specifically to test the 1990 theory put forth
by Lighthill and Blake that a multiplicative propulsive enhancement exists for Gymnotiform and
Balisiform swimmers based on the ratio of body and fin heights. Until now, the theory has not
been experimentally tested. Proof of such a momentum enhancement could have a profound effect
on unmanned underwater vehicle design and shed light on the evolutionary advantage to body-fin
ratios found in nature, shown as optimal for momentum enhancement in Lighthill and Blake’s theory.
Thrust tests for various body heights were conducted in a recirculating flow tank at different flow
speeds and fin flapping frequencies. When comparing different body heights at different frequencies
to a ’no-body’ thrust test case at each frequency no momentum enhancement factor was found. Data
in this thesis indicate there is no momentum enhancement factor due to the presence of a body on
top of an undulating fin.

The purpose of this study was to investigate the validity of linear position
transducers (LPTs), The Open Barbell System (OBS) and Tendo Weightlifting Analyzer
System (TWAS), in comparison to criterion measure Optotrak Certus (OC3D). Further,
we aimed to compare LPTs against each other. Twenty-five resistance-trained males were
recruited, and reported to the laboratory for one day of data collection. Subjects
performed one-repetition maximum (1 RM) testing of the squat, then had a standardized
rest before completing one set to failure with 70% 1 RM. There was no significant
difference in average velocity (AV) between either LPT vs. OC3D. T-tests revealed
significant differences between LPTs and OC3D peak velocity (PV) (OBS: p=0.02080;
TWAS: p<0.01). A significant difference was detected between OBS and TWAS PV
(p<0.01). OBS and TWAS demonstrated concurrent validity compared to OC3D for AV
(OBS: p=0.2014; TWAS: p=0.5466). Neither LPT was a valid measure ofPV (OBS:
p=0.0208; TWAS: p<0.01).

The design and construction of a tri-cable, planar robotic device for use in neurophysical rehabilitation is presented. The criteria for this system are based primarily on marketability factors, rather than ideal models or mathematical outcomes. The device is designed to be low cost and sufficiently safe for a somewhat disabled individual to use unsupervised at home, as well as in a therapist's office. The key features are the use of a barrier that inhibits the user from coming into contact with the cables as well as a "break-away" joystick that the user utilizes to perform the rehabilitation tasks. In addition, this device is portable, aesthetically acceptable and easy to operate. Other uses of this system include sports therapy, virtual reality and teleoperation of remote devices.