The primary goal of the Air Muscle Artificial Limb project is to design, build, and control a robotic hand with realistic finger motions; all gesticulations are made possible via forces produced by pneumatic muscles. Dr. Kathleen Lamkin-Kennard, of the Bio-Mechanical Engineering Dept. at RIT, facilitated the project with specific product requirements and team guidance. In order to achieve the project objective, a team of engineers was divided into Design/Build, Controls, and Air Muscles sub-teams. During the initial stage of the project, three fingers were prototyped, control algorithms were created, and air muscles were characterized in order to produce a consistently and accurately controlled hand. The final product is an aluminum hand with index, middle, and ring phalanges that are capable of achieving four degrees of freedom (DOF): flexion, extension, abduction, and adduction.

Jonathan Kasper / Project Manager Matthew Lewis / Design Lead Mark McKann / Controls Team

Jenna Fike / Lead Engineer Josa Hanzlik / Air Muscle Team Nick Rappa / Controls Team

Dr. Kathleen Lamkin-Kennard / Advisor Ellen Cretekos / Air Muscle Team Eric Giang / Controls Team

Project #: P08023

Design/Build Team : responsible for configuring and producing a robotic hand that was capable of the requisite hand motions; this included the production of:

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Controls Team : in charge of implementing control mechanisms and algorithms for management of the solenoid valves that were used to manipulate air flow

Air Muscle Team : focused on the development and implementation of air muscles for the project:

o Determined the method for constructing reproducible muscleso Evaluated optimal sizes and materialso Characterized the bladders so that they were capable of consistently producing the necessary forces

o CAD drawingso Prototypeso Final functioning hand

Artificial Limb CAD DesignFinger CAD Design

Read configuration file to determine relative

potentiometer range

Wait for User’s Command

Call AB/AD module

Determine current % flexion

Finger Abducts or Adducts

Cycle extension valve once

Cycle flexion valve once

Finger Flexes by Instructed

Percentage

= Ab/Adduction Instruction

= n% Flexion Instruction

= Too Flexed

= Too Extended

= Absolute Direction

LabVIEW Relay Board

Valves

DAQ

Air Muscles

Potentiometer

Feedback

System Architecture

Portable Air Compressor

Logic Diagram of Finger Actuation Control

Push-to-connect

Mesh Material: PET

Inside Tubing: Rubber

Eye-Hook

Air Muscle Displacement Based on Pressure and Length

Dr. Kathleen Lamkin-Kennard, Mr. John Wellin, Mr. Scott Kennard, Dr. Steven Day, Dr. Matthew Marshall, Mr. William Scarbrough, Mr. Edward Hanzlik, Mr. David Hathaway, Dr. Mark Kempski, Mr. Robert Kraynik, Mr. Steven Kosciol, and Mr. Jonathan Niebielski Special Thanks to RIT New Faculty Development Grant for Funding

o 3 Fingers capable of the 4 DOF: Flexion/Extension & Abduction/Adduction

o Control Feedback obtained via Linear Potentiometers

o Forces produced by 9 Air Muscles with the following lengths:

o [3] Abduction & [3] Adduction – 2.5 in

o [3] Flexion – 7 in

o Ease of air muscle serviceability

o User-Friendly LabVIEW Interface

o Addition of pinky, thumb, and wrist motion

o Grasping capabilities and tactile feedback

o Simultaneous flexion of varying degrees

o Air muscles with increased life expectancy

o Improvements in maintenance and assembly

Final Limb