Portable Pneumatic Power-Harvesting Ankle-Foot-Orthosis

2008 ◽  
Author(s):  
Robin Chin ◽  
Elizabeth T. Hsiao-Wecksler ◽  
Eric Loth ◽  
Andrew Alleyne ◽  
Scott Manwaring ◽  
...  
Keyword(s):  
Power Source ◽  
Power Harvesting ◽  
Ankle Motion ◽  
Ankle Foot Orthosis ◽  
Locking Mechanism ◽  
External Power Source ◽  
Cam Follower ◽  
External Power ◽  
Pneumatic Power ◽  
Foot Orthosis

In this paper, we present a novel ankle-foot-orthosis (AFO) design that controls ankle motion by providing a plantarflexion stop with free dorsiflexion during gait. The biomechanical controls are accomplished with a unique application of a cam-follower design that uses pneumatic power harvested via an air bellow embedded into the insole of the AFO (Figure 1). This portable design is self-contained and does not require any external power source to provide for the plantarflexion stop locking mechanism. It is the first step in a series of untethered fluid-powered orthotic devices.

scholarly journals A pneumatic power harvesting ankle-foot orthosis to prevent foot-drop

2009 ◽  
Vol 6 (1) ◽  
pp. 19 ◽  
Author(s):  
Robin Chin ◽  
Elizabeth T Hsiao-Wecksler ◽  
Eric Loth ◽  
Géza Kogler ◽  
Scott D Manwaring ◽  
...  
Keyword(s):  
Foot Drop ◽  
Power Harvesting ◽  
Ankle Foot Orthosis ◽  
Pneumatic Power ◽  
Foot Orthosis

Biomechanical Comparison of a New Dynamic Ankle Orthosis to a Standard Ankle-Foot Orthosis During Walking

2020 ◽  
Vol 142 (5) ◽  
Author(s):  
Chloe L. Chung ◽  
Denis J. DiAngelo ◽  
Douglas W. Powell ◽  
Max R. Paquette
Keyword(s):  
Angular Velocity ◽  
Cartilage Damage ◽  
Three Dimensional ◽  
Frontal Plane ◽  
Ankle Injuries ◽  
Ankle Motion ◽  
Ankle Foot Orthosis ◽  
Plantar Pressures ◽  
Biomechanical Comparison ◽  
Foot Orthosis

Abstract Patients who sustain irreversible cartilage damage or joint instability from ankle injuries are likely to develop ankle osteoarthritis (OA). A dynamic ankle orthosis (DAO) was recently designed with the intent to offload the foot and ankle using a distractive force, allowing more natural sagittal and frontal plane ankle motion during gait. To evaluate its efficacy, this study compared ankle joint kinematics and plantar pressures among the DAO, standard double upright ankle-foot orthosis (DUAFO), and a nonorthosis control (CON) condition in healthy adults during walking. Ten healthy subjects (26 ± 3.8 yr; 69.6 ± 12.7 kg; and 1.69 ± 0.07 m) walked on a treadmill at 1.4 m/s in three orthosis conditions: CON, DAO, and DUAFO. Ankle kinematics were assessed using a three-dimensional (3D) motion capture system and in-shoe plantar pressures were measured for seven areas of the foot. DAO reduced hallux peak plantar pressures (PPs) compared to CON and DUAFO. PPs under toes 2–5 were smaller in DAO than DUAFO, but greater in DUAFO compared to CON. Early stance peak plantarflexion (PF) angular velocity was smaller in DAO compared to CON and DUAFO. Eversion (EV) ROM was much smaller in DUAFO compared to CON and DAO. Early stance peak eversion angular velocity was smaller in DAO and much smaller in DUAFO compared to CON. This study demonstrates the capacity of the DAO to provide offloading during ambulation without greatly affecting kinematic parameters including frontal plane ankle motion compared to CON. Future work will assess the effectiveness of the DAO in a clinical osteoarthritic population.

Precise quantitative addition of multiple reagents into droplets in sequence using glass fiber-induced droplet coalescence

The Analyst ◽  
2015 ◽  
Vol 140 (3) ◽  
pp. 701-705
Author(s):  
Chunyu Li ◽  
Jian Xu ◽  
Bo Ma
Keyword(s):  
Glass Fiber ◽  
Power Source ◽  
Droplet Coalescence ◽  
External Power Source ◽  
External Power ◽  
Serial Addition

Serial addition of reagents with controlled volumes is performed using a glass fiber-induced droplet coalescence method without the requirement for an external power source.

scholarly journals Noiseless intensity amplification of repetitive signals by coherent addition using the temporal Talbot effect

2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Reza Maram ◽  
James Van Howe ◽  
Ming Li ◽  
José Azaña
Keyword(s):  
Optical Pulse ◽  
Wave Train ◽  
Extinction Ratio ◽  
Power Source ◽  
Wave System ◽  
Talbot Effect ◽  
Physical Processes ◽  
External Power Source ◽  
External Power ◽  
Time Average

Abstract Amplification of signal intensity is essential for initiating physical processes, diagnostics, sensing, communications and measurement. During traditional amplification, the signal is amplified by multiplying the signal carriers through an active gain process, requiring the use of an external power source. In addition, the signal is degraded by noise and distortions that typically accompany active gain processes. We show noiseless intensity amplification of repetitive optical pulse waveforms with gain from 2 to ~20 without using active gain. The proposed method uses a dispersion-induced temporal self-imaging (Talbot) effect to redistribute and coherently accumulate energy of the original repetitive waveforms into fewer replica waveforms. In addition, we show how our passive amplifier performs a real-time average of the wave-train to reduce its original noise fluctuation, as well as enhances the extinction ratio of pulses to stand above the noise floor. Our technique is applicable to repetitive waveforms in any spectral region or wave system.

A photovoltaic self-powered gas sensor based on a single-walled carbon nanotube/Si heterojunction

Nanoscale ◽  
2017 ◽  
Vol 9 (47) ◽  
pp. 18579-18583 ◽  
Author(s):  
L. Liu ◽  
G. H. Li ◽  
Y. Wang ◽  
Y. Y. Wang ◽  
T. Li ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Visible Light ◽  
Gas Sensor ◽  
Power Source ◽  
Single Walled Carbon Nanotube ◽  
External Power Source ◽  
External Power ◽  
Gas Molecules ◽  
Self Powered ◽  
Trace Concentrations

A self-powered gas sensor activated by visible light which can detect trace concentrations of gas molecules without an external power source.

scholarly journals A 3D-printed hand-powered centrifuge for molecular biology

2019 ◽  
Author(s):  
Gaurav Byagathvalli ◽  
Aaron F. Pomerantz ◽  
Soham Sinha ◽  
Janet Standeven ◽  
M. Saad Bhamla
Keyword(s):  
Molecular Biology ◽  
Low Cost ◽  
Power Source ◽  
Medical Diagnostics ◽  
Resource Limited Settings ◽  
Resource Limited ◽  
External Power Source ◽  
External Power ◽  
3D Printed ◽  
Proof Of Principle

The centrifuge is an essential tool for many aspects of research and medical diagnostics. However, conventional centrifuges are often inaccessible outside of conventional laboratory settings, such as remote field sites, require a constant external power source, and can be prohibitively costly in resource-limited settings and STEM-focused programs. Here we present the 3D-Fuge, a 3D-printed hand-powered centrifuge, as a novel alternative to standard benchtop centrifuges. Based on the design principles of a paper-based centrifuge, this 3D-printed instrument increases the volume capacity to 2 mL and can reach hand-powered centrifugation speeds up to 6,000 rpm. The 3D-Fuge devices presented here are capable of centrifugation of a wide variety of different solutions such as spinning down samples for biomarker applications and performing nucleotide extractions as part of a portable molecular lab setup. We introduce the design and proof-of-principle trials that demonstrate the utility of low-cost 3D printed centrifuges for use in remote and educational settings.

scholarly journals Recent Advances in Self-Powered Electrochemical Systems

Research ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Linglin Zhou ◽  
Di Liu ◽  
Li Liu ◽  
Lixia He ◽  
Xia Cao ◽  
...  
Keyword(s):  
Mechanical Energy ◽  
Power Source ◽  
Triboelectric Nanogenerator ◽  
Application Domain ◽  
Important Research ◽  
Electrochemical System ◽  
Electrochemical Systems ◽  
External Power Source ◽  
External Power ◽  
Self Powered

Electrochemistry, one of the most important research and production technology, has been widely applicated in various fields. However, the requirement of external power source is a major challenge to its development. To solve this issue, developing self-powered electrochemical system (SPES) that can work by collecting energy from the environment is highly desired. The invention of triboelectric nanogenerator (TENG), which can transform mechanical energy into electricity, is a promising approach to build SPES by integrating with electrochemistry. In this view, the latest representative achievements of SPES based on TENG are comprehensively reviewed. By harvesting various mechanical energy, five SPESs are built, including electrochemical pollutants treatment, electrochemical synthesis, electrochemical sensor, electrochromic reaction, and anticorrosion system, according to the application domain. Additionally, the perspective for promoting the development of SPES is discussed.

Reduction in the Knee Adduction Moment During Walking Using Laterally-Wedged Shoes With and Without Ankle Support

2010 ◽  
Author(s):  
Jennifer Erhart ◽  
Thomas Andriacchi
Keyword(s):  
Knee Adduction Moment ◽  
Dynamic Effects ◽  
Medial Compartment Osteoarthritis ◽  
Ankle Motion ◽  
Ankle Foot Orthosis ◽  
Rate Of Progression ◽  
High Maximum ◽  
Ankle Support ◽  
Lateral Wedges ◽  
Foot Orthosis

A high maximum adduction moment at the knee during walking has been associated with an increased rate of progression [1] and worse treatment outcome [2] of medial compartment osteoarthritis (OA) of the knee. Laterally-wedged insoles and shoes have been shown to reduce the knee adduction moment in healthy and osteoarthritic populations [3,4]. However, the mechanism of the effectiveness of such interventions is not well understood. Toda et al. showed that subtalar strapping with laterally wedged insoles in osteoarthritic subjects can improve valgus correction, but the authors did not look at the dynamic effects of walking [5]. A second study looked at the effects of lateral wedges with both semi-rigid ankle support and a rigid ankle-foot-orthosis and found a reduction in the adduction moment only with ankle support and a 10° lateral wedge. The wedge alone did not produce a reduction in the adduction moment [6]. Thus, it seems that the mechanism of action of the lateral wedge may be influenced by ankle motion.

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