Automated Inspection

touchscreentestingInline inspection during the production process can catch defects early, minimizing rework, ensuring consistent quality, and providing fine-grain traceability.

Traditionally, the deployment cost for inspection systems has meant that they are often only installed for final inspection or perhaps for a critical intermediate point along the production line.

Distributing inspection requires that the inspection equipment be

  • Easy to deploy for inspection of components, subassemblies, and devices
  • Readily re-taskable to handle product variations or new target inspection areas
  • Compact and not disruptive to the existing production workflow

The Cytons are used for inspection in two ways, either to present components and devices to an inspection camera or by doing direct inspection with an arm-mounted camera.

For example, one customer had been performing manual inspection of devices and wanted to add automated inspection. Automated inspection could ensure consistent quality assessment and detect subtle defects difficult for a person to perceive.

One constraint for automation was that it readily integrate with the current manual production process. Workstations on either side of the inspection station involve manual assembly. In their prior process, a person would perform assembly and then place a subassembly in an output tray within reach of the inspector. The inspector would leave approved subassemblies in an output tray for pick up by the downstream assembler. Subassemblies could be freely placed on the trays, minimizing distraction from the assembler’s focus on the intricate assembly work.

For the Cyton AOI inspection solution, the Cyton was trained to recognize and grasp the subassemblies using the on-arm camera, then present the subassemblies to an inspection camera. Based on the inspection result, the Cyton places the subsassembly in the ‘OK’ output buffer or in a defect output area. The assemblers upstream and downstream of the inspection cell could freely place and pickup the subassemblies as before. No fixturing or precise placement of the input subassemblies was required.

The compact footprint of the Cyton actually reduced the size of the inspection station. In addition, the Cyton would pick and place from an open table, and then insert and hold the subassemblies in a light-shielded chamber for inspection. This open table space, coupled with the easy reprogramming of the arm, allows rapid re-allocation of Input vs. Output buffers or ‘OK’ vs. ‘Defect’ buffer areas on the table.

Sometimes retasking is a planned need, expected when new product variations are introduced to the production line. Often, though, retasking is an immediate need in response to a discovery about the device being produced. For example, during one recent new product introduction (NPI), inspection was planned for a set of key surfaces on a mobile device. As part of the NPI process, the customer decided to add inspection within a battery compartment of the mobile device. This required an entirely new set of view angles, none aligned with the prior views used for surface cosmetic inspection. With the Cyton-based AOI inspection system, a motion path was added to present the device to the inspection camera at just the right view angles. This update required less than a day to setup and test. No change to the inspection station hardware was required. In contrast, our customer estimated that adding the new views with a traditional inspection station would have required a hardware modification and 2+ weeks of effort.

In other automated inspection systems with the Cyton, an on-arm machine vision camera is swept over the inspection target. The Cyton’s 7 axes and the built-in Actin robotic control enables the arm to look at devices by scanning over them, orbiting around them, or reaching inside and looking around. The Cyton capabilities are particularly beneficial for components and devices with 3D structure. The ability to look at subcomponents and device surfaces from a variety of angles can be critical for finding partially hidden or subtle defects.