823 research outputs found
A novel hardware approach to integrating active and passive rehabilitation in a single exoskeleton
The proposed exoskeleton is based on the elbow joint where patients can have active and passive rehabilitation in a single structure without changing its configuration. The structural formation of the exoskeleton has been designed in such a way that it offers two working regions namely; actuator based active rehabilitation in the first phase and passive rehabilitation in the second phase. The solution for integrating these two phases has been implemented using an innovative passive locking mechanism which uses a spring-based system for transformation. The stiffness of the spring is utilized to switch between active and passive rehabilitation regions. Besides this there are some other advantages this exoskeleton offers such as reduction of the actuation torque as well as ease of control. The paper is divided into three parts: the first part describes the existing designs, the second part gives an overview of the developed mechanism with structural description and the last part provides the solution with technical specification
Design Proposal for a Portable Elbow Exoskeleton
Exoskeleton based rehabilitation for post-stroke recovery is being aggressively pursued due to unavailability of adequate number of caregivers and huge investment for the manual treatment [1]. The structural framework for providing different training exercises is not similar for all exoskeletons and there is no standardized protocol for rehabilitation following stroke [2]. Various approaches have been undertaken to come up with customized exoskeleton design for implementing a specific type of exercise. Though a few exoskeletons have proved to be beneficial in terms of clinical outcomes, there is still a long way to go before a useful rehabilitation device becomes acceptable to the users. After reviewing the 46 exoskeletons (commercial or prototypes) [3], two key requirements can be considered for the design of an exoskeleton; the structural parameter which decides the size, weight and the ease of control and the other is the nature of rehabilitation therapy which defines the type and intensity of the exercises performed during training
A mechanism for elbow exoskeleton for customised training.
It is well proven that repetitive extensive training consisting of active and passive therapy is effective for patients suffering from neuromuscular deficits. The level of difficulty in rehabilitation should be increased with time to improve the neurological muscle functions. A portable elbow exoskeleton has been designed that will meet these requirements and potentially offers superior outcomes than human-assisted training. The proposed exoskeleton can provide both active and passive rehabilitation in a single structure without changing its configuration. The idea is to offer three levels of rehabilitation; namely active, passive and stiffness control in a single device using a single actuator. The mechanism also provides higher torque to weight ratio making it an energy efficient mechanism
Assessment of joint parameters in a Kinect sensor based rehabilitation game
Copyright © 2019 ASME. A Kinect sensor based basketball game is developed for delivering post-stroke exercises in association with a newly developed elbow exoskeleton. Few interesting features such as audio-visual feedback and scoring have been added to the game platform to enhance patient’s engagement during exercises. After playing the game, the performance score has been calculated based on their reachable points and reaching time to measure their current health conditions. During exercises, joint parameters are measured using the motion capture technique of Kinect sensor. The measurement accuracy of Kinect sensor is validated by two comparative studies where two healthy subjects were asked to move elbow joint in front of Kinect sensor wearing the developed elbow exoskeleton. In the first study, the joint information collected from Kinect sensor was compared with the exoskeleton based sensor. In the next study, the length of upperarm and forearm measured by Kinect were compared with the standard anthropometric data. The measurement errors between Kinect and exoskeleton are turned out to be in the acceptable range; 1% for subject 1 and 0.44% for subject 2 in case of joint angle; 5.55% and 3.58% for subject 1 and subject 2 respectively in case of joint torque. The average errors of Kinect measurement as compared to the anthropometric data of the two subjects are 16.52% for upperarm length and 9.87% for forearm length. It shows that Kinect sensor can measure the activity of joint movement with a minimum margin of error
Optimization and design of a cable driven upper arm exoskeleton
This paper presents the design of a wearable upper arm exoskeleton that can be used to assist and train arm movements of stroke survivors or subjects with weak musculature. In the last ten years, a number of upper-arm training devices have emerged. However, due to their size and weight, their use is restricted to clinics and research laboratories. Our proposed wearable exoskeleton builds upon our extensive research experience in wire driven manipulators and design of rehabilitative systems. The exoskeleton consists of three main parts: (i) an inverted U-shaped cuff that rests on the shoulder, (ii) a cuff on the upper arm, and (iii) a cuff on the forearm. Six motors, mounted on the shoulder cuff, drive the cuffs on the upper arm and forearm, using cables. In order to assess the performance of this exoskeleton, prior to use on humans, a laboratory test-bed has been developed where this exoskeleton is mounted on a model skeleton, instrumented with sensors to measure joint angles and transmitted forces to the shoulder. This paper describes design details of the exoskeleton and addresses the key issue of parameter optimization to achieve useful workspace based on kinematic and kinetic models.</jats:p
Parametric Seismic Analysis of Tall Buildings with Different Geometry and Constant Plan Area.
In this study, seismic analysis of high rise building frames have been carried out considering four buildings of different geometrical plan but same area , three diaphragms and four seismic zones. In this way total 48 frames were analysed for 27 load combinations. STADD-Pro software has been used for analysis purpose. Structural analyses results are collected in terms of maximum moments in columns and beams, storey displacement, peak storey displacement which are critically analysed to quantify the effects of various parameters
Structural and Optical Studies of 100 MeV Ni+7 Irradiated Cadmium Selenide Thin Films
The effect of irradiation with Swift (100 MeV) Ni+ 7 ions on the structural and optical properties of
Cadmium Selenide (CdSe) thin films have been investigated at different fluencies in the range of 1 1011-
1 1013 ions/cm – 2. The CdSe films on glass substrates were prepared by thermal evaporation. The structural
and optical changes with respect to increasing fluence were observed by the means of X-ray diffraction
(XRD), UV-VIS and Raman spectroscopy. After irradiating the films with Ni+ 7 ions XRD show the increased
in peak intensity and crystallite size with increasing fluence. The UV-VIS-IR spectroscopy revealed
that there is decrease in band gap energy of the films after irradiation with increasing fluencies.
Raman spectrum for as deposited and irradiated films show two peak, one at 209 cm – 1 and at 410 cm – 1
which is assigned to the longitudinal optical (LO) phonon mode
Structural and Optical Studies of 100 MeV Ni+7 Irradiated Cadmium Selenide Thin Films
The effect of irradiation with Swift (100 MeV) Ni+ 7 ions on the structural and optical properties of
Cadmium Selenide (CdSe) thin films have been investigated at different fluencies in the range of 1 1011-
1 1013 ions/cm – 2. The CdSe films on glass substrates were prepared by thermal evaporation. The structural
and optical changes with respect to increasing fluence were observed by the means of X-ray diffraction
(XRD), UV-VIS and Raman spectroscopy. After irradiating the films with Ni+ 7 ions XRD show the increased
in peak intensity and crystallite size with increasing fluence. The UV-VIS-IR spectroscopy revealed
that there is decrease in band gap energy of the films after irradiation with increasing fluencies.
Raman spectrum for as deposited and irradiated films show two peak, one at 209 cm – 1 and at 410 cm – 1
which is assigned to the longitudinal optical (LO) phonon mode
Moving towards a control technique to help small firms monitor and control key marketing parameters: a survival aid
This article considers that one way
to help the small- and medium-sized
enterprise (SME) to survive is to
offer it a robust but simple
monitoring and control technique
that would help it manage the
business effectively and this, in
turn, should help to increase its
chances of survival. This technique
should also be of interest to all
people involved with monitoring or
advising a large number of small
enterprises or business units within
a larger organization. For example,
a bank manager or a small business
consultant responsible for a
portfolio of firms. The authors
utilize process control techniques
more often used in production and
inventory control systems to
demonstrate how one might
monitor the marketing ``health'' of
small firms
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