Monday, April 21, 2014

A Hand in Automation

Introduction

A recent assessment of advances in robotics published by the Packaging Machinery Manufacturers Institute (PMMI) attributed increased robotic dexterity to the overall rise in robotics for manufacturers:

While the benefits of manpower reduction and increased operating efficiency are enough to justify the use of robots in the manufacturing line, the real growth in robotics is due to the advances in the design of end-of-arm-tooling (EOAT) or the end effector.

(PMMI. “2014 Trends in Robotics Market Assessment.” PMMI, Reston Virginia: 2014, p. 16.)

This increase is also true for those involved in primary and secondary packaging processes, especially for packagers of pharmaceuticals, diagnostics, and medical devices. Indeed, innovations in vacuum cups, pneumatic grippers, etc., coupled with advances in mechanical design tools using 3-D simulations of EOAT allow engineers to create ever more flexible and nimble robotic tooling capable of handling multiple tasks. As an authorized robotics system integrator for FANUC America, ESS engineers have designed hundreds of robotic end effectors for a range of applications from assembling drug delivery devices to machine infeeds, robotic carton and case loading, track & trace inspection, and robotic palletizing. Each application requires a different approach to the design of the robot EOAT.

Types of EOAT

Robotic end effector styles can be categorized as vacuum, gripper, platen, or some combination, which can be referred to as hybrid EOAT. Recent developments in “bean bag” soft robotic grippers offer variations on these basic categories. Magnetic EOAT represent yet another category of end effectors beginning to make headlines in automation. The application will dictate which type of EOAT works best.

Vacuum EOAT

ESS deploys vacuum-style EOAT most often. In this design, one or more vacuum cups with vacuum pumps are fitted to a base plate that attaches to the robot. When air is applied, the pumps create a vacuum seal with the cups, allowing the robot to lift whatever is attached to the vacuum cup. This style is best for lifting objects and cases that have a smooth surface. The wide range of vacuum cups available today handles everything from large cases to individual products.
Just a Few of the Wide Range of Vacuum Cup Shapes and Sizes Available to EOAT Designers

Gripper / Pincher EOAT

Gripper-style EOAT represents the next most designed style that ESS sees. Also called pincher EOAT, pneumatically controlled grippers can clamp around an object (or objects) and lift it. Objects with irregular shapes or non-smooth surfaces can be handled more reliably with this type of EOAT. Gripper EOAT is also ideal for applications where the robot must manipulate the product, such as shaking a bottle. In case packing such products as foil pouches, gripper EOAT can be fingered to grab products from a stacker.
Three-sided Grippers Allow Robot to Shake the Bottle without Dropping (left) Pinchers Firmly Grip Vials (right) 
Fingered Gripper EOAT Can Grab Foil Pouches, etc. From a Stacker

Hybrid EOAT

ESS sometimes integrates vacuums with gripper EOAT to create a more stable hybrid end effector for irregularly shaped packages. The vacuum cups affix to the smooth parts of the irregular product while the grippers prevent slippage.
EOAT with Vacuum Cups and Side Grippers Give Added Support When Case-Packing Bottles with Topserts (Portions of the EOAT have been masked to protect proprietary designs.)

Platen EOAT

Platen end effectors also employ vacuum pumps, but rather than using suction cups, the plate of the EOAT is punched with numerous holes. A foam pad is then placed over the plate. When the vacuum pump is applied the entire plate becomes a vacuum, allowing the robot to pick entire layers of product at once.
Platen EOAT Picking a Layer of Bottles from a Tote

Multi-Zone and Multi-Function EOAT

EOAT design has also advanced in terms of how much one end effector can actually do. Multi-function EOAT allows a single robot end effector to perform multiple tasks. For example, ESS’s CEL 5 Case Erector / Loader incorporates an EOAT that uses a vacuum arm to pick and erect RSC cases and move them across a bottom taper. The same EOAT then picks objects that have been automatically collated at the infeed and places them in the same RSC case that it just erected. The same EOAT also bumps the case out of the robotic cell to an integrated top case closer or manual closing station.
 
One EOAT Erects the RSC Case (left) and Loads it (right)

EOAT for Palletizers

Even palletizing end effectors can be designed for more than one product or purpose. ESS designed a pallet cell end effector that allowed the pharmaceutical manufacturer to palletize large bottles into crates, picking three bottles at one time. ESS engineers programmed the same robot and end effector to nudge the bottles into their correct position to allow room for more bottles within the crate. Palletizer EOAT can be “multi-zoned” devices that arrange the vacuum cups in such a way that multiple case sizes can be handled with a single EOAT, reducing the cost for size parts and eliminating lengthy changeover times.
Multi-zone Palletizing EOAT (left) and EOAT with “Nudge Blade” for Crating Bottles (right) (Portions of the EOAT have been masked to protect proprietary designs.)

Advanced Design Tools

Software that allows 3D modeling of a robot end effector as well as simulation design software allows designers to fully visualize a robot end effector and test its functionality in a virtual environment. This allows engineers to fully test the interoperation of vacuum and grippers in hybrid EOAT as well as verify speed and product handling. By designing the EOAT in a virtual environment first, engineers can reduce the R&D time required to specify correct vacuum cup sizes and configurations, as well as vacuum pump PSI, and other details.
Concept Case Erector / Loader EOAT (left) and Final EOAT (right)

Conclusion

Today’s advanced EOAT design tools and components have allowed EOAT designers to create ever more flexible, nimble and functional robot end effectors. This increased functionality has allowed robotic automation to expand into every part of the manufacturing and packaging processes. The 2014 PMMI report concludes that:

For manufacturers, the future will be more robots – working across the entire manufacturing process -performing repetitive tasks and doing the heavy lifting in collaboration with human workers...Robots of the future will move along the manufacturing line tirelessly improving throughput, eliminating waste and reducing overall operational costs.

(PMMI. “2014 Trends in Robotics Market Assessment.” PMMI, Reston Virginia: 2014, pp. 35-36.)

 ESS has years of experience successfully integrated robotic solutions into manufacturing processes as well as primary and secondary packaging processes. Our EOAT designs handle the most delicate products and safely palletize the most robust shipping cases. Contact us to learn more about ESS robotic manufacturing and packaging solutions.

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