Wearable Mobile Arm Support

The goal of this project is to improve upon the current arm support device by making it portable, reducing friction, improving force mapping, and making it safe. This was achieved by creating a portable model, testing pulley friction, continuous device testing, and redesigning cams within the system.

Background
Patients with neurological damage to the brain from events such as stroke often exhibit a loss in arm range of motion on the contralateral side of the body. It has been shown that by simulating a low-gravity environment, through gravitational support to the arm, a patient can achieve a larger range of motion. This increased range of motion may be sufficient to allow the completion of otherwise unattainable movements and tasks such as functional ADLs (activities of daily living) or tasks that are beneficial to promote further recovery of lost range of motion. The University of Idaho has designed an arm support that supports the arm and could allow stroke patients to regain lost function and mobility. Our objective is to understand its shortcomings, identify sources of error, and improve the system.

Design Constraints

 * Device must
 * Safe to the user
 * Low friction to allow for close mapping of desired forces
 * Wearable/Mobile
 * Device should
 * Be comfortable for extended use
 * Sleek enough to avoid collisions with environment
 * Wearable
 * Able to put on and taken off in under 2 minutes
 * Be aesthetically pleasing
 * Improve elbow stability when the arm is extended

=Project Learning= {| class="wikitable"

Pulley Board Trials
Our initial test setup can be seen on the left. The objective of this test was to observe how different masses, numbers of pulleys, and types of cable effects friction. We also compared how different cable diameters and pulley diameters effect the system. While doing this test a mass was moved up and down by hand which lead to a high margin of error.

Surgical Tubing Fatigue
Preliminary tests were taken to allow for comparisons after modifications and to check for ongoing issues. These tests ended up showing us that the bands used to store energy were fatiguing over time. An image of the results can be seen to the left. We believe that the fatigue was mainly caused due to constant tension on the tubes and repeated use. To resolve this we replaced the tubing.

Contact Points and Deformation
Upon receiving the project we looked over the current model closely and found a contact point between a cam and the bracket as seen on the left. We removed material from the bracket, which in turn reduced the friction in the device. We also found that the cams were deforming due to the high stresses within the system. We later redesigned the cams to eliminate this problem.
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=Design= {| class="wikitable"

Shaft/Cams Redesign
An image of the redesigned shaft can be seen on the left. We decided to make the cams and the shaft one solid part and slightly modified the shapes to avoid stress concentrations. The shaft was also made out of steel rather than aluminum to eliminate deformation further.

Pulley Board 2.0
The pulley board was redesigned to reduce the error that was prominent in the initial tests. A motor was used to move the mass rather than by hand which moved the mass at a more consistent velocity. This helped reduce the effects of inertia while testing and produced more accurate results.

Wearable/Portable
JACE AND KYLO HIT GET THIS

Safety Cover
A cover was designed to improve the devices aesthetics as well as providing safety for the user. The design is lightweight and uses several arches to support a nylon cover. This cover protects the user from a potential cable snap, pinch points, and sharp edges.
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=Results= {| class="wikitable"

Pulley Board
Not Complete

FEA Analysis
FEA Stuff

Force Mapping
Preliminary tests were taken to allow for comparisons after modifications and to check for ongoing issues. These tests ended up showing us that the bands used to store energy were fatiguing over time. An image of the results can be seen to the left. We believe that the fatigue was mainly caused due to constant tension on the tubes and repeated use. To resolve this we replaced the tubing.
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Meeting Minutes

 * [[Media:2014_FuelRodDefectDetection_Sep16_2014_Minutes.pdf|September 16, 2014]]


 * [[Media:2014_FuelRodDefectDetection_Sep30_2014_Minutes.pdf|September 30, 2014]]


 * [[Media:2014_FuelRodDefectDetection_Oct7_2014_Minutes.pdf|October 7, 2014]]


 * [[Media:2014_FuelRodDefectDetection_Oct28_2014_Minutes.pdf|October 28, 2014]]


 * [[Media:2014_FuelRodDefectDetection_Nov6_2014_Minutes.pdf|November 6, 2014]]


 * [[Media:2014_FuelRodDefectDetection_Nov13_2014_Minutes.pdf|November 13, 2014]]


 * [[Media:2014_FuelRodDefectDetection_Jan20_2015_Minutes.pdf|January 20, 2015]]


 * [[Media:2014_FuelRodDefectDetection_Feb10_2015_Minutes.pdf|February 10, 2015]]


 * [[Media:2014_FuelRodDefectDetection_Feb17_2015_Minutes.pdf|February 17, 2015]]


 * [[Media:2014_FuelRodDefectDetection_Mar3_2015_Minutes.pdf|March 3, 2015]]


 * [[Media:2014_FuelRodDefectDetection_Mar24_2015_Minutes.pdf|March 24, 2015]]


 * [[Media:2014_FuelRodDefectDetection_Apr21_2015_Minutes.pdf|April 21, 2015]]

Other
Project Timeline

[[Media:2014_FuelRodDefectDetection_SPERT_Tests_Summary.pdf|INL SPERT Tests Summary]]

[[Media:2014_FuelRodDefectDetection_Profilometer_Research_Summary.pdf|Profilometer Research Summary]]

[[Media:2014_FuelRodDefectDetection_Team_Contract.pdf|Team Contract]]

[[Media:2014_FuelRodDefectDetection_Design_Review.pdf|Design Review (November 21, 2014)]]

[[Media:2014_FuelRodDefectDetection_Expo_Presentation.pdf|2015 Expo Technical Presentation]]