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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 19 of 19 for “"Human ankle"”.
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Kinematic study of human ankle control during walking
In order to determine the extent to which ankle motion is voluntarily controlled during walking, angular velocity measurements at the ankle were taken in two cases. In the first case, subjects were seated and instructed to move their ankle as quickly as possible in eight directions indicated by a …
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Spatial mechanisms for modelling the human ankle passive motion
… articular surfaces guide passive motion at the human ankle joint complex is fundamental for the design of relevant surgical treatments. The dissertation presents a possible improvement of this knowledge by a new kinematic model of the tibiotalar articulation. In this dissertation two one-DOF …
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Quantitative characterization of multi-variable human ankle mechanical impedance
Ankle mechanical impedance, which is a dynamic relationship between angular displacement and the corresponding torque at the ankle joint, plays a key role in natural interaction of the lower-extremity with the environment. The human ankle is a biomechanically complex joint consisting of three bones …
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Sagittal plane characterization of normal human ankle function across a range of walking gait speeds
The function of the human ankle during the stance phase of walking is characterized in terms of simple mechanical elements that can reproduce the sagittal plane dynamics of a normal ankle. The dynamics of the ankle are taken from the analysis of the slow, normal, and fast gait of 10 healthy young …
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In-vivo cartilage contact biomechanics : an experimental and computational investigation of human ankle joint complex
… to investigate the in-vivo biomechanics of human ankle joint complex in this work. The in-vivo kinematic data showed that the talocrural joint contributes more in dorsi/plantarflexion, while the subtalar joint is more responsible for inversion/eversion and internal/external rotation of the …
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A 3D neuromuscular model of the human ankle-foot complex based on multi-joint biplanar fluoroscopy gait analysis
During the gait cycle, the human ankle complex serves as a primary power generator while simultaneously stabilizing the entire limb. These actions are controlled by an intricate interplay of several lower leg muscles that cannot be fully uncovered using experimental methods alone. A combination of …
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Powered ankle-foot prosthesis for the improvement of amputee walking economy
The human ankle provides a significant amount of net positive work during the stance period of walking, especially at moderate to fast walking speeds. On the contrary, conventional ankle-foot prostheses are completely passive during stance, and consequently, cannot provide net positive work. …
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Biomechanics and dynamics of turning
… the effects of turning around a 90° corner for humans with and without lower-limb, below-knee amputations. I find that amputees appear to compensate for their limb loss by reducing the extent to which they shift their prosthetic limbs under their pelvis during a turn. I also find that there is …
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Mechanical bracing solutions to decrease tibial slippage of Anklebot
Anklebot is a general-purpose therapeutic robot designed to guide the human ankle through motions with appropriate assistance. Anklebot relies on accurate position feedback from its actuators, which may or may not be corrupted due to slippage of Anklebot. This study seeks to quantify the slippage …
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Preliminary Design Approach for Prosthetic Ankle Joints Using Compliant Mechanisms
… design approaches and models for prosthetic ankle joints using kinematic models of the human ankle and compliant mechanisms technology. Compliant mechanisms offer several potential design advantages over traditional rigid-body designs including high reliability and low cost. These design …
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Simulating control of the ankle joint
… to fill this need. Models and simulations of the human ankle were created in PyODE. This program is useful for creating simple models where the programmer desires a high level of control over model parameters. Simulations of the ankle kicking a ball and taking a step were created to examine the …
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Design and control of a Two-Degree-of-Freedom powered ankle-foot prosthesis
Powered ankle prostheses have been proven to improve the walking economy of transtibial amputees although these powered systems are usually much heavier in weight than conventional prostheses. All commercial powered ankle prostheses that are currently available can only perform …
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EMG control of prosthetic ankle plantar flexion
Similar to biological human ankle, today's commercially available powered ankle-foot prostheses can vary impedance and deliver net positive ankle work. These commercially available prostheses are intrinsically controlled. Users cannot intuitively change ankle controller's behavior to perform …
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Understanding the Differential Effects of Dexamethasone on the Metabolism of Healthy and Diseased Articular Cartilage
… cartilage explant monoculture PTOA model to use human donor knee cartilage. Proteins released into the media were clustered by the kinetics of their release over three weeks. This analysis further details the classification of biomarker candidates by their timing of release from cartilage, which …
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Energy Harvesting from the Human Body for Wearable and Mobile Devices
… there is a huge amount of energy stored in the human body. While walking, there is a large amount of power dissipated in the human body as negative muscle work and the energy loss by impact. By sourcing locally and using locally, human body energy harvesting is a promising solution. This …
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Mechanical and Biologic Impact of Dynamic Loading on Bovine and Human Models of Osteoarthritis
… and biochemical composition of cartilage in human osteochondral tissues when treated with exogenous inflammatory cytokines. Bovine knee cartilage and human ankle cartilage-bone explants were used in vitro with a cytokine challenged to mimic an OA disease state. A load-controlled dynamic …
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Improving Effectiveness of Robot-Assisted Ankle Rehabilitation via Biomechanical Assessment and Interaction Control
The human ankle joint plays a significant role in maintaining body balance during ambulation, but it is particularly susceptible to musculoskeletal and neurological disorders. A general rehabilitation program for ankle injuries requires intensive efforts from therapists and patients over prolonged …