TEST RIG DEVELOPMENT GROUPVoice of the EngineerProject: R13301
Rochester Institute of Technology
Design Project Management (0303.735.01 & 0304.730.01 )
R13301 TEAMS & MEMBERS
EP Printing Team Jonathan Erbelding & Sakif Noor
Garlock Team Usman Asad & Jessica Fuss
Polymer Membrane Team Steven Lucchesi & Seaver Wrisley
PMTR MOTIVATION & BACKGROUND Mission Statement:
The Mechanical and Biomedical Engineering Departments at the Rochester Institute of Technology (RIT) have developed a need for a test device capable of measuring the mechanical properties of biologically relevant materials.
Principle Needs: The Biomaterials professors (Drs. Lamkin-Kennard and
Gaborski) need classroom equipment for student lab experiments.
Satisfied by Biomaterials Instructional Test Rig. Bill Spath needs a research quality test machine to test
Electroactive Polymers (EAPs) in in vivo conditions for his Ph.D. work. He needs to measure voltage output as a function of loading, and force output as a function of applied voltage.
Satisfied by ASSET Test Stand.
ENGINEERING REQUIREMENTS
Biomaterials student test machine Single-axis loading Analog display Lower accuracy Manual control
ASSET Test Stand Multi-axis loading Fully automated interface (Matlab or LabView) Closed loop control of loading Higher accuracy Environmental control capabilities Aqueous environment capabilities
PMTR CURRENT TECHNOLOGY
Currently, there is no lab equipment available for educational use in the two Biomaterials courses. Typical tensile testers damage
biomaterials at the clamping points, rendering the test invalid
Previous/Current RIT Projects: Lowell Smoger’s Biaxial Test Rig P06218 Bausch & Lomb Eye
Membrane Indenter Bill Spath’s ASSET concept
Transverse Plunger
Axial Servo Driver
Environmental Tank
Figure 1: Automated Smart Sensing EAP Tank
Transverse Plunger Linkage Box
EAP
PMTR CURRENT TECHNOLOGY- ASSET (AUTOMATED SMART SENSING EAP TANK )
Preliminary design by Bill Spath Biaxial tension tester in horizontal direction for in-plane
loading Indenter for out-of-plane loading Capable of being
completely filled with aqueous solution
Interior made from biologically inert materials
POSSIBLE SOLUTIONS- COMPONENT OPTIONS
Functions
Input load/deflection Computer program Knob controlling motor speedUser physically generates load
(drill press style handle)Hang a weight
Generate and apply load/displacement
Hydraulic pistonDirect drive electric motor & ball screw (would require reaction to torsion)
Electric motor or drill press handle to rack & pinion
Cable going to a suspended weight
Position measurement options
Position sensor Micrometer stages Calipers Ruler
Load measurement options Load cell Measure the weight
Environmental conditions, voltage across specimen
Sensors to measure, computer controls heater, humidifier, power supply
Manually adjust voltage, heater knobs based on thermometers or other
measurements
Provide power for system components
DC for sensors and AC for motors
DC for everythingDC for sensors, human power
to actuateNo electricity at all
Secure specimenTraditional clamp, possibly with rubberized or knurled
gripsMold the specimen into the grips
Rubber band shaped specimen over parallel rods
Structural materials Durable plastics (such as ABS) Metals
ASSET tank materials Lexan Polycarbonate Acrylic
ASSET tank sealing Gaskets Silicone sealant
Generally decreasing complexity →
PROPOSED SENIOR DESIGN PROJECTS
Biomaterials Instructional Test Rig Design & Build Will design and build classroom test machines for the lab component
of the Biomaterials courses. Staffing: 3-5 MEs Budget Estimate: $300 per Machine
ASSET - Biaxial Tension Tester Redesign & Build Will redesign Lowell Smoger’s machine to have a variable x:y loading
ratio (his can only apply a 1:1 ratio). Will serve as a base for the other projects to integrate into. Staffing: 3 MEs, 2 EEs Budget Estimate: $2,125 (ASSET total ~ $6,500)
ASSET - Indentation Tester Design & Build Will produce an indentation tester that will integrate into mounting
provided by Biaxial Tension Tester team. ASSET - Environmental Chamber Design & Build
Will design and build the tank itself, with environmental controls. Will be responsible for building a Matlab or LabView control program.
TO BE DETERMINED BY MSD COMMITTEE How many of the 12 Biomaterials
Instructional Test Rigs will be built by their senior design team. Could build one machine per design iteration.
Start dates for the 2nd and 3rd ASSET projects Biaxial Tension Tester Redesign & Build Indentation Tester Design & Build Environmental Chamber Design & Build