The purpose of this study is to investigate the variables which are inherent in those reaches and moves accompanied by body bend and body rotation about hips and ankles. The variables, and the interactions between variables, are investigated and conclusions are given as to which variables would affect a time-standard classification. / M.S.

The object of production has been described as “to produce a required quality by the best and cheapest method at the required time.” In order to accomplish this aim, the use of scientific methods has become so common and extensive a practice in industry that it is now considered the basis of modern industrial development. Many developments have been made in the several fields to which this principle has been applied, among which is motion and time study. At first, time study, originated by Frederick W. Taylor, the father of scientific management, and motion study, developed by Frank B. and Lillian M. Gilbreth, each more or less made separate and independent progress- time study being used mainly for determining time standards, while motion study was used for improving methods. However, it has gradually been realized that motion study and time study not only supplement each other, but are actually inseparable; and it is becoming common practice to combine the two together as Motion and Time study, or as it is sometimes called, Methods Engineering. / Master of Science

Thesis (MSc) -- University of Stellenbosch, 2003. / ENGLISH ABSTRACT: A need for intelligent robotic machines is identified. Research and experiments have focussed on stable, or relatively stable, dynamic simulated systems to demonstrate the feasibility of embedding advanced AI into dynamic physical systems. This thesis presents an attempt to scale the techniques to a dynamically highly unstable system - the coordination of movements in a humanoid model. Environmental simulation, articulated systems and artificial intelligence methods are identified as three essential layers for a complete and unified approach to embedding AI into robotic machinery. The history of the physics subsystem for this project is discussed, leading to the adoption of the Open Dynamics Engine as the physics simulator of choice. An approach to articulated systems is presented along with the EBNF of a hierarchical articulated system that was used to describe the model. A revised form of evolution is presented and justified. An AI model that makes use of this new evolutionary paradigm is introduced. A variety of AI variants are defined and simulated. The results of these simulations are presented and analysed. Based on these results recommendations for future work are made. / AFRIKAANSE OPSOMMING: Die beheer van dinamiese masjiene, soos intelligente robotte, is tans beperk tot fisies stabilie - of relatief stabiele - sisteme. In hierdie tesis word die tegnieke van kunsmatige intelligensie (KI) toegepas op die kontrole en beheer van 'n dinamies hoogs onstabiele sisteem: 'n Humanoïede model. Fisiese simulasie, geartikuleerde sisteme en kunmatige intelligensie metodes word geïdentifiseer as drie noodsaaklike vereistes vir 'n volledige en eenvormige benadering tot KI beheer in robotte. Die implementasie van 'n fisiese simulator word beskryf, en 'n motivering vir die gebruik van die sogenaamde "Open Dynamics Engine" as fisiese simulator word gegee. 'n Benadering tot geartikuleerde sisteme word beskryf, tesame met die EBNF van 'n hierargiese geartikuleerde sisteem wat gebruik is om die model te beskryf. 'n Nuwe interpretasie vir evolusie word voorgestel, wat die basis vorm van 'n KI model wat in die tesis gebruik word. 'n Verskeidenheid van KI variasies word gedefineer en gesimuleer, en die resultate word beskryf en ontleed. Voorstelle vir verdere navorsing word gemaak.

Thesis (MScPhysio)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Introduction-The golf swing is a complex, sequenced movement of body segments. This movement is smooth and well timed and is referred to as the kinematic golf sequence. This kinematic sequence illustrates the rotational speed, which occurs between the upper and lower body segments. Hip rotation plays an integral part to a sound kinematic sequence by providing a pivotal point between the upper and lower body segments, ensuring a synchronised golf swing. Hip rotation kinematics during a golf swing has received relatively little attention compared to other body segments’ movements. However, clinicians need to have a clear understanding of the rotational contribution that each hip make during golf swing in order to enhance the athlete’s performance and reduce the risk of injury. The aim of this descriptive research project was to obtain and investigate the total passive and total dynamic rotation range of movement in both the lead and trail hips of healthy, young adult, male golfers. Methodology-Seven, low handicapped, male golfers between the ages of 18 and 40 years were randomly selected in the Western Cape region from areas surrounding Stellenbosch University’s Tygerberg campus. A questionnaire gathered participant demographics that determined participatory eligibility. A preliminary reliability study established a baseline measurement for passive total articular hip rotation. Seatadjusted total passive hip rotation ranges of motion (ROM) measurements were collected with a hand-held inclinometer. Dynamic total hip rotation kinematic data was captured during a golf swing with an 8-camera video analysis system (VICON). Data analyses were performed with Statistica version 10. Hand-held inclinometer intra-rater reliability was determined with a two-way interclass correlation, standard error of measurement and a 95% confidence interval level. A Spearman correlation coefficient determined correlation between the total passive and total dynamic rotation range of movement in both the lead and trail hips. Results-Passive intra-rater reliability was reported as 0.81 (95% CI: 0.46-0.96). The total average passive articular range between the lead (62.1° ±6.4°) and trail hip (61.4° ±3.8°) did not report any significant difference (p=0.8). The total average dynamic golf swing articular range between the lead (29° ± 6.5°) and trail hip (35.° ±7.8°), was reported as significantly (p=0.04) asymmetric. The findings also demonstrated a positive correlation between the passive and dynamic total articular range in a lead hip, whereas a negative correlation was reported in a trail hip. During the golf swing the lead hip utilised 46.4%(± 8) of the total passive available hip rotation, whereas the trail hip utilised 58.8% (±13.2). Discussion and Conclusions-The findings of this study show that, the passive rotation ROM in a hip (LH=62°; TH=61°) of a golf player does not exceed the available range it has during a golf swing. The golfer’s hip utilises 46% of the available passive range of movement in the lead hip and 59% in the trail hip. In the clinical field careful consideration should be given to the motivation behind mobilizing, treating or stretching the hips of a golf player. These findings can be incorporated in future research on the relationship between hip-rotation ROM and reduction in the incidence of injuries amongst golfers. / AFRIKAANSE OPSOMMING: Inleiding-Die gholfswaai is n komplekse, opeenvolgende beweging van verskeie liggaamsegmente. Hierdie gladde opeenvolgende bewegings word die kinematiese gholfpatron genoem. Hierdie kinematiese opeenvolgende bewegings bied ’n illustrastrasie van die rotasiespoed waarteen die beweging tussen die boonste en onderste liggaamsegmente plaasvind. Heuprotasie speel ’n deurslaggewende rol in hierdie glad verlopende kinematiese proses. Dit dien as ’n spilpunt tussend die boonste en onderste kwadrant, wat op sy beurt weer ’n gesinkroniseerde gholfswaai verseker. Die heuprotasie kinamtieka tydens n gholfswaai het relatief minder aandag ontvang in vergelyking met ander liggaamsegmente. Klinici moet instaat gestel word om ’n duidelike begrip aangaande die bydrae wat heuprotasie tydens ’n golfswaai lewer, te ontwikkel. Die atleet se prestasie kan sodoende verbeter word, en die risiko tot beserings kan ook sodoende voorkom word. Die doel van hierdie beskrywende navorsingsprojek was om te bepaal wat die totale passiewe en die totale dinamies rotasie omvang van die leidende en volgende heupe van gesonde jong mans wat gholf speel, te ondersoek. Metodologie-Sewe gholf-geskoolde manlike gholf spelers met ’n lae voorgee en tussen die ouderdom van 18 en 40 jaar is ewekansig gekies. Hierdie kandidate is gekies uit die omliggende gebiede van die Stellenbosch Tygerberg kampus in die Wes-Kaap waar hulle relatief naby woonagtig was. ’n Vraelys is aangewend om demografiese eienskappe van elke deelnemer in te samel. Hierdie inligting wat deur die vraelys bekom is, is gebruik om te bepaal of die deelnemers in aanmerking is vir die studie. ’n Voorlopige, intra-meter betroubaarheidstudie is gedoen vir passiewe, totale artikulêre heuprotasiemetings wat met ’n hand hanteerbare hoek meter geneem is. ’n Algemene fisiese ondersoek is in die biomeganiese labaratorium afgehandel om te bepaal of die deelnemers geskik is vir die toetse. Sit-aangepaste passiewe totale hip rotasie beweging metings was ingesamel met 'n hand hanteerbare hoek meter. Intra-meter betroubaarheid is bepaal met ’n twee-rigting interklas korrelasie, standaard foutmeting en ’n 95% vertroue interval vlak. Dinamiese totale heup kinematiese rotasiedata is afgeneem met ’n hoë-spoed 3-D videografiestelsel (VICON) tydens 'n gholfswaai. Data-ontleding is bereken met ’n Statistica weergawe 10. Die gemiddelde en Spearman korrelasie koëffisiënt is gebruik as aanwysers van verspreiding. Resultate-Passiewe inter-meter betroubaarheid word geraporteer as 0.81 (95% KI: 0.46-0.96). Die resultate dui op ’n onbeduidende totale passiewe artikulêre reeks verskille tussen die leidende (voorste) (62.1 ± 6.4 °) en volgende (agterste) heupe (61.4 ° ± 3.8 °). ’n Beduidende totale dinamiese artikulêre reeks van die leidende (29 ° ± 6.5 °) en volgende heupe (35.9 ° ± 7.8 °) is tydens die gholfswaai bereik. Verdere resultate toon ’n positiewe korrelasie tussen die passiewe en dinamiese totale artikulêre reeks in die leidende heup, terwyl ’n negatiewe korrelasie gerapporteer word vir die volgende (agterste) heup. Tydens ’n gholfswaai gebruik die leidende heup 46.4% (± 8%) van die totale passiewe beskikbaar heuprotasie, terwyl die opvolgende (agterste) heup 58.8% (± 13.2%) aanwend. Bespreking en gevolgtrekking-Die bevindinge van hierdie studie toon dat tydens ’n gholfswaai, ’n gesonde gholfspeler nie die beskikbare passiewe beweging wat in sy heup bestaan oorskry nie. Slegs 46.4% van die beskikbare passiewe beweging in sy leidende heup word gebruik, en 58.8% van sy agterste heup. Die klinisie moet deeglike oorweging gegee word aan die motivering agter die mobilisering, strekke en die behandeling van die heupe van ’n gholfspeler. Hierdie bevindings kan in toekomstige navorsing geimplimenteer word om die verhouding wat tussen die omvange vand heuprotasie bestaan te ondersoek. Die voorkoming van moontlike toekomstige beserings in gholfspelers kan ook verhoed word.

The purpose of the study was to examine selected mechanical factors involved in hitting a baseball to the same and opposite fields. Special emphasis was placed on an identification of those factors which distinguish players of different hitting abilities. Twenty male college level baseball players, ten in each of two groups, hit six pitched baseballs, three each to two assigned areas of the playing field. The movement patterns for the opposite field and same field batting swings appeared to be similar in form with differences between the two swings due to (a) differences in the angular displacements at the left wrist and left elbow joints and (b) differences in the temporal characteristics.

Preterm birth (PTB) is the leading cause of childhood death and effects 10% of babies worldwide. First-time diagnosis is difficult, and as many as 95% of all PTBs are intractable to current therapies. The processes of both preterm labor and normal parturition are poorly understood, in part because pregnancy is a protected environment where experimentation contains the risk of causing harm to the gestation and fetus. This proposes the need for non-invasive investigations to understand both normal and high-risk pregnancies. Furthermore, each pregnancy can vary significantly which adds the complex need for patient-specific investigations. To address this need, we propose the development of parameterized ultrasound-based finite element analyses to study the mechanics of the womb. As a first step, this dissertation work conducts sensitivity analyses on cervical, uterine, and fetal membrane parameters as well as model boundary conditions to determine which factors have the greatest impact on cervical tissue stretch. The effects of the range of patient geometries and material properties are reported. Findings show that a soft and short cervix result in greatest stretch at the internal os, and fetal membrane detachment increases cervical stretch. Additionally, patient-specific finite element analyses are performed on low- and high-risk cohorts and results between the two are compared. Patient geometries are documented at various gestational timepoints, and the effect of a cervical pessary is determined based on changes in cervical geometry and stiffness. Findings showed that a soft cervix correlates with sooner delivery, and that high pessary placement is ideal to decrease stretch at the internal os.

In this dissertation, the design and development of a hybrid robotic system that simulates dynamic biomechanical tasks of the lower extremity with emphasis on knee and hip joints are presented. The hybrid system utilizes a mechanical hip and a cadaveric knee/ankle component and can accelerate the whole complex towards the ground. This system is used to simulate complex athletic movements such as landing from a jump at various anatomical orientations of the lower extremity with muscle action. The dynamic response of the lower extremity is monitored and analyzed during impulsive contact between the ground and the cadaveric leg. The cadaveric knee is instrumented to measure strain of the Anterior Cruciate Ligament (ACL) during simulated high impact sports activities. The mechanical hip allows various kinematics of the hip including flexion as well as abduction. In addition to the flexion and abduction of the mechanical hip, the controlled flexion and extension of the cadaveric knee allows for simulation of complex tasks such as landing from a jump. A large number of tests were performed at various anatomical positions utilizing this device to simulate landing from a jump. ACL strain was measured during these tasks using a Differential Variance Resistance Transducer (DVRT). Ground Reaction Force and muscle forces were measured and monitored using AmCell load cells recorded using the LabView software. one-inch and 6-inch jump landing heights were used for all the simulations. The tests were performed at differing angles of hip flexion (0°, 30°, 45°, 60°) and at two different ankle positions. Plantar flexion and flat-footed landing conditions were simulated and compared in all degrees of hip flexion. These tests were repeated with and without hip abduction in order to study the effects of these landing positions on ACL strain. Hip flexion was found to effect ACL strain: as angle of hip flexion increases, ACL strain decreases. This occurred in both abducted and non-abducted hip positions. Ankle landing position had an effect only in small drop heights, while hip abduction had an effect in large drops. Future tests must be completed to further study these effects. These studies showed that the robotic system can simulate dynamic tasks, apply muscle forces, and move the cadaveric tissue in three dimensional biomechanical positions. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

The purpose of the present study was to investigate if any relationship exists between anthropometric measurements with average concentric velocity (ACV) at various intensities in the back squat and the number of repetitions able to be performed during a set to volitional fatigue at 70% of one-repetition maximum (1RM). It was hypothesised that short femurs and total height would be related to slower ACVs and lower total number of repetitions performed. 58 resistance trained subjects were recruited and attended one day of data collection. Subjects performed 1RM testing of the back squat followed by two single repetition sets at 30-90% of 1RM and a 70% of 1RM set to fatigue. There was no significant correlation between femur length and height with ACV at any intensity (p>0.05). A significant negative correlation existed between both height (r=-0.39, p=0.003) and femur length (r=-0.31, p=0.018) with total number of repetitions performed. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection

The human spine is an integral part of the human body. Its functions include mobilizing the torso, controlling postural stability, and transferring loads from upper body to lower body, all of which are essential for the activities of daily living. However, the many complex tasks of the spine leave it vulnerable to damage from a variety of sources. Prolonged walking with a heavy backpack can cause spinal injuries. Spinal diseases, such as scoliosis, can make the spine abnormally deform. Neurological disorders, such as cerebral palsy, can lead to a loss of torso control. External torso support has been used in these cases to mitigate the risk of spinal injuries, to halt the progression of spinal deformities, and to support the torso. However, current torso support designs are limited by rigid, passive, and non-sensorized structures. These limitations were the motivations for this work in developing the science for design of torso exoskeletons that can improve the effectiveness of current external torso support solutions. Central features to the design of these exoskeletons were the abilities to sense and actively control the motion of or the forces applied to the torso. Two applications of external torso support are the main focus in this study, backpack load carriage and correction of spine deformities. The goal was to develop torso exoskeletons for these two applications, evaluate their effectiveness, and exploit novel assistive and/or treatment paradigms. With regard to backpack load carriage, current torso support solutions are limited and do not provide any means to measure and/or adjust the load distribution between the shoulders and the pelvis, or to reduce dynamic loads induced by walking. Because of these limitations, determining the effects of modulating these loads between the shoulders and the pelvis has not been possible. Hence, the first scientific question that this work aims to address is What are the biomechanical and physiological effects of distributing the load and reducing the dynamic load of a backpack on human body during backpack load carriage? Concerning the correction of spinal deformities, the most common treatment is the use of a spine brace. This method has been shown to effectively slow down the progression of spinal deformity. However , a limitation in the effectiveness of this treatment is the lack of knowledge of the stiffness characteristics of the human torso. Previously, there has been no means to measure the stiffness of human torso. An improved understanding of this subject would directly affect treatment outcomes by better informing the appropriate external forces (or displacements) to apply in order to achieve the desired correction of the spine. Hence, the second scientific question that this work aims to address is How can we characterize three dimensional stiffness of the human torso for quantifiable assessment and targeted treatment of spinal deformities? In this work, a torso exoskeleton called the Wearable upper Body Suit (WEBS) was developed to address the first question. The WEBS distributes the backpack load between the shoulders and the pelvis, senses the vertical motion of the pelvis, and provides gait synchronized compensatory forces to reduce dynamic loads of a backpack during walking. It was hypothesized that during typical backpack load carriage, load distribution and dynamic load compensation reduce gait and postural adaptations, the user’s overall effort and metabolic cost. This hypothesis was supported by biomechanical and physiological measurements taken from twelve healthy male subjects while they walked on a treadmill with a 25 percent body weight backpack. In terms of load distribution and dynamic load compensation, the results showed reductions in gait and postural adaptations, muscle activity, vertical and braking ground reaction forces, and metabolic cost. Based on these results, it was concluded that the wearable upper body suit can potentially reduce the risk of musculoskeletal injuries and muscle fatigue associated with carrying heavy backpack loads, as well as reducing the metabolic cost of loaded walking. To address the second question, the Robotic Spine Exoskeleton (ROSE) was developed. The ROSE consists of two parallel robot platforms connected in series that can adjust to fit snugly at different levels of the human torso and dynamically modulate either the posture of the torso or the forces exerted on the torso. An experimental evaluation of the ROSE was performed with ten healthy male subjects that validated its efficacy in controlling three dimensional corrective forces exerted on the torso while providing flexibility for a wide range of torso motions. The feasibility of characterizing the three dimensional stiffness of the human torso was also validated using the ROSE. Based on these results, it was concluded that the ROSE may alleviate some of the limitations in current brace technology and treatment methods for spine deformities, and offer a means to explore new treatment approaches to potentially improve the therapeutic outcomes of the brace treatment.

Preterm birth is a public health problem affecting almost 15 million newborns each year, with almost one million cases annually being fatal. Despite many decades of research, identifying high-risk pregnancies remains difficult. Even with the therapies currently available to clinicians, 95% of preterm births are seemingly intractable. We see a great opportunity for engineers to collaborate with clinicians to help reduce the adverse health impact of this phenomenon. This work is a multi-faceted contribution to the study of the biomechanical problem of preterm birth. We portray the successful, full-term, pregnancy as a delicate balance of organ geometry, tissue deformation behavior, and the physical interaction between the uterus, cervix, and fetal membranes. The cervix is our focus, as its preterm ripening and dilation are the final pathway to premature delivery. We consider a selection of geometric and material factors, studying their impact on the loading that occurs in the cervix. We also study the mechanical implications of the use of a cervical pessary on the mechanical environment of pregnancy. Our mechanical analyses use a custom parameterized model of the pregnant anatomy, coupled with Finite Element Analysis techniques, to allow for rapid model development. In addition, we present a push towards the in-vivo measurement of cervical material properties by way of a phantom study using modern MRI techniques.