Overview:

The fiber-frax pick-and-place cells are a unique set of in-line feeding systems. Each cell acquires fiber frax pieces from corrugate containers, locates them with machine vision, and precisely places them onto an air-bag assembly on the associated pass-through conveyor.  The cell consists of a SCARA robot, corrugate box feeder, interlayer stripper and debris collector, and machine vision system.

Process Description:

As the main air bag assemblies arrive at the cell, a single piece of fiber frax is acquired from the corrugate shipping container using a high-flow vacuum head.  In the container, the fiber frax sheets are arranged in stacks, with each sheet separated from its neighbors by a non-porous interlayer plasticized paper.

Once acquired, the sheet is carried to a stripping station, where the paper interlayer is grabbed from below, using a pneumatic actuator fitted with a vacuum cup.  The paper is pulled from the bottom of the fiber frax and deposited into a collection bin as trash.

The stripped fiber frax sheet is then carried over a machine vision station, where the location of the sheet is determined relative to the gripper.  The register sheet is then precisely placed onto the air bag assembly, and carried to the next station.

Technical Challenge:

The main challenge of this cell was creating a means to grip the fiber frax materials. Being porous, a typical vacuum gripper could not grip a sheet. To overcome this challenge, a high-flow vacuum gripper was created using a regenerative blower as a vacuum source. Air flow and drag were used, instead of vacuum pressure, to keep the materials on the gripper. It was also found during development that even the high-flow gripper could not acquire a sheet while in contact with the sheet. However, a sheet could be "sucked" up to the gripper from a flat surface or from a stack of similar sheets by holding the gripper a few millimeters away with the vacuum source engaged.

Features:

SCARA robot;
Machine vision;
Custom feeding systems;
Pallet transfer.