Flexible Material Handling

Past, Present, and Future

Professor Steve Derby

MANE Department

October 18, 2006

Professor Steve Derby

• Designed automation work cells and conducted related research for over 35 companies

• 8 US patents in automation and mechanisms

• Authored “Design of Automatic Machinery”

• 6 years work in Fuel Cell MEA process design

• 4 years work B&L soft contact lens inspection

• Started 2 robotic automation companies

Flexible Material Handling

RPI team has had many projects in past 25 years with material handling of flexible objects

• Fabrics

• Hydrated contact lenses

• Springs

• Surgical robotics

• Fuel Cell Electrodes & Membranes

Flexible Material Handling - Fabric

RPI team developed a machine to make custom shaped swimming pool covers consisting of many panels

• CAD/CAM process

• PC based controls

• Large (9 ft x 75 ft) gantry robot

• Unrolled fabric (woven polypropylene)

• Sensed and compensated for fabric defects

• Marked with 2 colored inks (cut lines, sew lines, alignment fiducials)

• Rolled up for cutting process

Flexible Material Handling - Fabric

Flexible Material Handling - Fabric

RPI team created a robotic workcell to press men’s dress trousers (during manufacture) for Defense Logistics Agency (DLA)

• First tried to duplicate humans

• Sense wrinkles then smooth out

• Finally gripped with 4 grippers - easier

Flexible Material Handling - Fabric

Flexible Material Handling - Fabric

RPI team developed system for digital printing of textiles for sampling and small lots of custom designed fabric

• Developed unique CMYK color set jetable textile fiber reactive dyes

• Material handling (zero tension) of fabric

• Designed and built our own custom ink jet print heads with active redundancy, including sensing of condition of each individual orifice (thousands), and automated error recovery

• Created custom raster image processing (RPI)

• Built working Proof of Principle Model

Flexible Material Handling - Springs

RPI team created automation to handle springs for

• Kodak one time use camera assembly

• Texas Instruments sensor assembly

• Standard Gage (Brown & Sharpe) dial indicator assembly

Flexible Material Handling - Membranes

RPI team developed robotic end effector to handle fuel cell membrane

Flexible Material Handling - Membranes

Vacuum alone not sufficientSpatula used to break surface tension

Flexible Material Handling - Membranes

Stack Assembly Material Handling

• Automation is needed to handle (load/unload, transport, manipulate, align, assemble) stack components

• Bipolar plates, end plates

• Cell seals

• Electrodes

• MEA’s

• Electrodes and MEA’s are not rigid

Stack Assembly Research Challenges

• Validation of incoming components and materials• Robust and efficient handling of fragile flexible materials• Custom fixturing and end-of-arm tooling • Vision guided precision placement• Vision/sensing/tension control to avoid wrinkles• Assembly with tight geometric and force tolerance

(Incremental stack performance / leak test?)• Design for manufacture & assembly

Stack Assembly Material Handling

• Automation cannot simply duplicate present day human assembly techniques and rely on post assembly testing

• Research needs to be conducted to develop better methods with integrated modeling, design, sensing, & control

• Research will likely produce suggested stack component design rules

Stack Assembly Material Handling

• Lab demo shows early work to date

• Consortium needed to increase dialog & exchange with fuel cell component suppliers, fuel cell manufacturers, fuel cell users, & fuel cell researchers to accelerate progress

• No commercially viable product without automated assembly !!