Wheelchair Mounted Robotic Arm -AND- Wrist/Arm Support for Tremor Patients ATS Kyle Hurley, Graham Barrett, and Casey Brauchie University of Wyoming Department of Mechanical Engineering Assistive Technology Systems

Introduction Robotic Arm Project Wrist/Arm Support Project Cost Analysis Conclusions Questions ATS

Robotic Arm Objective ATS Images Courtesy of:

Design Specifications 1.Support 3 lb. Dynavox Communication Device 2.Controlled via one pushbutton “Jelly Switch” 3.Less than 6” from wheelchair side 4.Easily removable from the wheelchair 5.Drip proof enclosures 6.No wheelchair alterations permitted – Auxiliary battery/circuitry ATS “Engineers shall hold paramount the safety, health and welfare of the public…” - American Society of Mechanical Engineers

Design Approaches Primary Arm (holds communication device) – Double Arm – Telescoping Arm – Single Arm Arm Detachment Mechanism – “Folding” arm, keeping attached to chair – Compression Clamp Power Transmission – Linear Actuator – Right Angle Worm Gear Motor – DC Gear Motor Torsional Spring Assist Control Circuitry – Microcontroller – Mechanical Relays via Logic Gate Control ATS

Mathematical Modeling -Torsional Spring Assist Model- ATS

Mathematical Modeling - FEA Model on Wheelchair Accessory Rail- ATS

Final Design ATS *Auxiliary Battery and Circuit Board located in a separate enclosure behind wheelchair seat.

Compliance Testing -Vertical Deflection- ATS

Final Design -Mounting and Connection to the Wheelchair- ATS

Final Design -Power Transmission Components- ATS Hub Bearings Torsion Spring DC Motor Shaft 3 inch

Final Design -Safety Considerations- ATS

Final Design -Control Circuitry- ATS 4 “ diameter pushbutton switch

Compliance Testing -Operational Current- ATS

Current/Future Scope of Assembly Currently designed for a Quantum Q6 Edge Wheelchair - Allows for greater user freedom - Reduces client’s need for assistance Minimal modification required to adapt to other wheelchairs - Adaptability accomplished by modification of mounting fixture Fits any communication device with 7/8” mount ATS

Wrist Support Objective ATS Image Courtesy of: Essential Tremors in Extremities: “Drug therapies are available and can help, though up to 50 percent of patients with essential tremor either don’t respond to the medications or find the side effects intolerable. And while creating surgical lesions or electrically stimulating the ventral intermediate nucleus of the thalamus can reduce essential tremor, few patients are willing to undergo such invasive surgeries.” Figure and quote: Precise-Essential-Tremor-Treatment#sthash.ams1yVtQ.dpuf

Design Specifications 1.Table top mounted 2.Easily transportable 3.No electrical control 4.Support variety of arm sizes 5.Arm removable by own strength 6.Forward/backward and side-to-side movement 7.Allow for activation of 1”x1” icon ATS

Design Approaches Base/Clamping Mechanism – Suction Cup – Clamp Damping Mechanism – Coil Over Shock – Gas Shock – Spring/Damper Wrist/Forearm Cradle – Inflatable Cuff – Velcro Strap/Memory Foam – Velcro Sleeve/Memory Foam ATS

Mathematical Modeling ATS (Hz)

Final Design ATS Device Weight: 8 [lb] Footprint: 11” x 9”

Final Design -Cradle and Arm Secure- -Rail System- -Mounting Mechanism- ATS

Final Design -Damping Mechanism- ATS

Current/Future Scope of Assembly Allows user to perform fine motor tasks while using touchscreen device - Enhances experience - Increases productivity Future Considerations - Reduce footprint of assembly - Electrical control feedback system ATS

Cost Analysis 1160 Man Hours Total (as of 4/24/14) ~1/3 time (387 hours) – Wrist Support ~2/3 time (773 hours) – Robotic Arm -Rate: $30/hr ATS Man Hour Cost Wrist SupportRobotic ArmTotal $11,610$23,190$34,800 Parts and Fabrication Costs Wrist SupportRobotic ArmTotal $600$500$1,100

Conclusion Did we meet the design specifications? ATS Robotic Arm Specification Met? Move 3 lb. Communication Device Up/DownYES Single Pushbutton ControlYES Not exceed 6" from side of wheelchairYES Easily RemovableYES No Wiring HarnessesYES No Wheelchair AlterationsYES Wrist Support Specification Met? Table Top MountedYES No Electrical ControlYES Support Variety of IndividualsYES Arm Removable by Own StrengthYES Forward/Backward & Side-to-Side MovementYES Ability to Activate 1"x1" IconYES TransportableYES

Acknowledgements Mr. Scott Morton (Instructor) Dr. Steven Barrett (Advisor) UW Machine Shop Gerry O’Berto (Falcon Electronics) Imagine! TM – Mr. Alex Andrews NSF-BME-RAPD Grant EPSCoR ATS

Questions? ATS