Robotic Arm Assist

Extending an Arm Toward the Future

Assisting Tecnalia's venture in designing a rehabilitation robot to aid stroke victims in their recovery.

2013 University of Idaho Capstone Senior Project



Mission
Mission: Our mission is to design and build a set of add-on modules to extend the functionality of an existing arm rehabilitation robot for TECNALIA.

Development and Project Goals
TECNALIA's Arm Assist Robot is an assistive robot for the rehabilitation of patients with upper limb neuromuscular impairment, specifically for patients who have suffered from a stroke. This assistive robot is accompanied by a tele-rehabilitation platform, thus allowing rehabilitation at home under supervision from the therapist by its quantitative evaluation.[]

The Robotic Arm Assist team, provided by the University of Idaho, will work through the capstone project to further develop the rehabilitation robot. The team will add to the overall functionality of the robot by providing TECNALIA with modules that will increase the current lift function, ability to rotate wrist, and ability to open and close the patients hand.

Sponsors
TECNALIA

http://www.tecnalia.com/en



University of Idaho

http://www.uidaho.edu/

Joe Osborn
Mechanical Engineering Student

Hometown: Gig Harbor, WA

Hobbies/Interests: My professional interests have always been geared towards helping people and making a difference, and thus I have been interested in the bio-med and bioengineering fields. In my free time I enjoy several board sports, including snowboarding, wake surfing and longboarding. Along with this I am an avid rock climber.

Plan for Future: I don’t have a set plan for what I will do after college, but at this point am determined to pass the PE exam as soon as possible.

Email: osbo8726@vandals.uidaho.edu

Roman Pacheco
Computer Engineering Student

Hometown: Arco, Id

Intersests include building and programing computer systems. Designing applications for implementation on microcontrollers and FPGA's. Ultimately would like to get into building and designing prosthetics or new medical technologies. Also spend time cooking, playing baseball and target shooting.

Email: pach7646@vandals.uidaho.edu



Brenden Staab
Biological Systems Engineering Student

Hometown: Worland, Wyoming

I enjoy skiing, reading, playing video games, and writing.

My future goals are to go into Biomedical Engineering.

Email: staa1939@vandals.uidaho.edu



Kadrie Swanson
Biological Systems Engineering Student

Hometown: Fargo, North Dakota

Hobbies/Interests: My professional interests center around the application of ergonomics in engineering, I apply this at my current internship working on the Advanced Accessible Pedestrian System. At the University of Idaho, I am a member of the Concrete Canoe Club in addition to being the president of the Agricultural and Biological Engineering Club and the secretary/fundraising chair to the Civil Engineering Club. In my spare time, I enjoy reading, cooking, and playing tennis.

Plan for the future: Eventually, I would love to have an engineering career focusing on how medical devices can be more functional for the user.

Email: swan5849@vandals.uidaho.edu



Steven Witkoe
Mechanical Engineering Student

Hometown: Spokane, WA

Hobbies and interests: My academic interests include robotics and fluid dynamics. I have taken multiple classes that relate to these topics including Robotic Kinematics, Control Systems, and Computational Fluid Dynamics. I also enjoy running, cooking and watching my hometown basketball team, the Gonzaga Bulldogs.

Plan for the future: After graduation I intend on pursuing a career in robotics. My ideal location would be somewhere in the Pacific Northwest. Wherever I end up, I plan on making a positive difference in peoples lives.

Email: witk8835@vandals.uidaho.edu

Dr. Joel Perry
Project Manager - TECNALIA, Rehabilitaiton Technologies Dept., Health Division

Adjunct Faculty - University of Idaho, Mechanical Engineering

Dr. Matthew Riley
Assistant Professor

http://www.uidaho.edu/engr/me/faculty/matthewriley

Chris Ohlinger
Graduate Student Mentor

Design Goals
Build grip, twist and lift modules to incorporate with current design with few alterations. Modules should be passive and able to stand alone, with the capabilities of being powered and used in conjunction with one another depending on the needs of the user.

Grip Module
1.	Sense full grip 1-2° (individual fingers not necessary)

2.	Incorporate vibration feedback when full grip is complete

3.	Help individuals complete tasks when necessary

Wrist Rotation Module
1.	Allow rotation of ±90°ideally (minimum ±60°)

2.	Help individuals complete tasks when necessary

Arm Elevation Module (Lift Module)
1.	Allow 4” of arm lift without lifting the device (2” minimum)

Other
Modify GUI to show output from modules and display them in a useful manner for the future development of games.

Project Learning
Throughout the project learning section of our design process we were able to conclude several general ideas in order to start progress in the correct general direction. Primarily, we have gained a greater understanding as to what is occurring in a stroke victim’s body from the lesion in the brain to the synergies that react when the person attempts to send a call from the brain to the body. The severity is rated on a Rankin Scale (RS). This understanding will help us design the modules specifically to help the victims in the RS that we are directed towards. Learn more: Stoke or cerebrovascular accident (CVA) []

Learn more: Muscle coordination and synergies []

Learn more: Clinical evaluation of stroke patients [] []

We have also gained much understanding in the hardware in use. Being able to look at the robot and visualize the scale of module we need to produce was helpful in comprehending the module’s needs. Research pricing and variability of strengths in hardware was helpful in producing a very rough budget. And researching the PCB hardware necessary to handle each of these modules we were able to understand its limits. Specifically, the research into components that measure distance and force was invaluable to our preliminary research and understanding how to design a functioning module that will meet the specifications provided for us.

Learn more: Initial pricing research, aluminum []

Learn more: Initial research on PCB

Finally, researching the ideas and current prototypes of the same general concepts on the internet was very important in understanding what the biggest challenges will be for us (i.e. making the design simple enough to actually use). This was very helpful in seeing flaw in other designs and well as general concepts that could be incorporated into our design (while being aware of patentability).

Learn more: Potentiometer []

Learn more: Load Cell []

In conclusion, we believe the amount of knowledge that we spent in the project learning section of our process will be very valuable in our conceptual design process along with throughout the entire design.

Morphology Chart Summary
Each member of the team was asked to sketch 3 to 5 design concepts to analyze. The designs were evaluated in a series of meetings by general feasibility. The ideas that were found infeasible were reconsidered and combined with other ideas in order to have a wide variety of viable options to consider.

Designs were then evaluated on capability, ranging from 1 to 5, the highest score being the most capable. Each specification was given a value (found immediately before the description) that represents its weight in reference to the other specifications; higher values are directly correlated to its importance. These numbers were then put into a morphology chart; the designs with the highest weighted totals were then further scrutinized to ensure that we chose the most advantageous designs.

The designs were then analyzed upon the following specs (1 being incapable 3 being moderately capable and 5 being very capable):

Grip Design's Specifications and Values
Help Open – (1) does this module assist in opening the hand

Help Close – (1) does this module assist in closing the hand

Accuracy – (1) would this module be able to accurately measure its task

Adjustable – (1.25) would this module be adjustable to all sizes

Easy to put on – (1.5) would this module be easy for the user to put on

Passive – (1) would this module be able to be made passive

Active – (.25) would this module be able to assist in making these movements for the user

Simplicity – (.25) how complex is this module

Machinability – (.6) how easy would this module be to machine in shop

Cost – (3) overall cost of this module (five being most cost efficient)

Integration – (.75) how easy would this module be to integrate into the current prototype

Longevity – (.9) will this module be a long lasting device

Safety – (2) will this module be safe for the average at home user

Lift Design's Specifications and Values
2” – (1) would this module have a range of 2”

4” – (1)would this module have a range of 4”

Accuracy – (1) would this module be able to accurately measure its task

Force required – (1.25) how much force would be necessary for the user to apply

Weight – (1.25) weight of module in device

Simplicity – (.6) how complex is this module

Machinability – (.9) how easy would this module be to machine in shop

Cost – (3) overall cost of this module (five being most cost efficient)

Integration – (1.5) how easy would this module be to integrate into the current prototype

Longevity – (.75) will this module be a long lasting device

Safety – (2) will this module be safe for the average at home user

Wrist Rotation's Specifications and Values
±90° – (.6) would this module have a range of 90°

±60° – (1) would this module have a range of 60°

Accuracy – (1.1) would this module be able to accurately measure its task

Easy to put on – (1.5) would this module be easy for the user to put on

Passive – (1) would this module be able to be made passive

Active – (.4) would this module be able to assist in making these movements for the user

Simplicity – (.75) how complex is this module

Machinability – (.75) how easy would this module be to machine in shop

Cost – (3) overall cost of this module (five being most cost efficient)

Integration – (1.25) how easy would this module be to integrate into the current prototype

Longevity – (.9) will this module be a long lasting device

Safety – (2) will this module be safe for the average at home user

Completed Morphology Chart found here []

Anthropometric Research
In order to have an ergonomically sound device, each portion of the device needs to be built in reference to the human body. Therefore, the 1st, 5th, 10th, 50th, 90th, 95th, and 99th percentile measurements of the length of the forearm, hand, and fingers along with the breadth of the four fingers, and the hand were taken of both male and females, with the intention of designing the modules to be able to fit 5th through the 95th percentiles.

Anthropometric data found here []

Concept Development
Following the preliminary research, the top rated modules from the morphology chart were chosen. These modules were then drawn in Solidworks and were analyzed, searching for errors and miscalculations.

Grip Concept Development




This simple Linear Grip Concept Design on the left allows the hand to be completely opened and resists being closed, which combats the gripping synergies, but does not allow for a natural grasp. The more complex Multi-grip Concept Design on the right simulates a more natural grasp which allows to assistance in opening and closing of the hand.

Wrist Rotation Concept Development




The wrist rotation concept design on the left has a center rotation pivot, giving the user a centralized rotation. Intended to simulate a natural movement. The wrist rotation concept design on the right is a half ring design, this rotation is a fully stabilized rotation. Stabilization along with the natural movement associated with the half ring would be beneficial for the user.

Lift Concept Development




The Scissor Concept Design on the left is a very simplistic lift mechanism that takes up a relatively small space and completes the action in both passive and active forms. The Linear Lift Concept Design is a lift mechanism that can be both passive and active but needs alteration of the original robot.

Meeting Minutes
Meeting Schedule:

Team meetings: Tuesdays at 2:30, Senior Design Suite

Team meetings with Mentor: Thursday at 10:00, Senior Design Suite

Sponsor meetings: As necessary, BEL 111

Frequently updated agendas [] and meeting minutes []available on dropbox.