Vision systems eliminate need for PCs

A trend in all-in-one vision systems is the inclusion of interfaces on the controller for a monitor, a keyboard, and a mouse.

By Ann Thryft, Contributing Technical Editor -- Test & Measurement World, 3/1/2011 12:00:00 AM

Email

In a vision system with multiple smart cameras, each camera performs single-point, local vision tasks and then feeds results over the network to a central processor (sometimes called an industrial controller) or to a central PC. Most of these smart cameras must be configured by a PC and then operated by either another PC or by a central processor. But according to Jeff Schmitz, marketing director for PPT Vision, some OEMs and integrators want an all-in-one, pre-integrated, embedded vision system that doesn't rely on a separate PC for either configuration or operation.

Read more "Tech Trends" columns. Read more from the March issue.

"It takes a lot of time to build your own vision system from scratch, usually with a standard programming language and a library of vision algorithms to develop and debug software and configure hardware," Schmitz said. "Instead, many engineers want to accelerate development and reduce the man-hours required to get the vision system operating in the production environment."

Because pre-integrated embedded vision systems have an embedded microprocessor, developers can program smart cameras on the same machine that will be used as the central controller on the factory floor—a feature that is helping to speed the adoption of these systems for inline use. For example, PPT Vision's Impact M-Series Embedded Vision System platform runs on an Intel CPU with Windows XP Pro, thus eliminating the need for a separate PC. The PC-based vision system provides basic connectivity in a manufacturing enterprise; it transmits data and images to plant machinery and connects to databases and SCADA systems, said Schmitz.

The system also runs PPT Vision's Impact vision software, which developers can use to program and operate the company's smart cameras and M-Series GigE cameras. When a multicamera controller such as the M-40—the company's first product in the M-Series line—is deployed with multiple dumb cameras that share its processing power, vision system designers can reduce the cost per inspection point compared to smart cameras, said Schmitz.

Another trend in small, all-in-one systems is the inclusion of  interfaces on the controller for a monitor, a keyboard, and a mouse. Such interfaces allow a ruggedized machine like the M-40 to connect directly to a display on the factory floor in place of a PC, so operators can monitor inspection processes, said Schmitz.

In a multicamera system, each camera performs separate inspection tasks, such as ensuring the coplanarity of components on a board, inspecting dimensions, or checking connectors. A system that triggers dumb cameras independently so they perform separate tasks running separate inspection or guidance programs, either simultaneously or at different times, is beneficial because the system can inspect multiple parts, as well as multiple processes, while a product is being manufactured, said Schmitz.

"Although smart cameras can be independently triggered, this ability has not been common in multicamera vision systems," he said. "In developing the M-Series system, we wanted to provide independent triggering, as well as improve intra-camera communications so that inspection data can be more easily shared and referenced."

Compact cameras use CMOS sensors Point Grey's Gazelle series of Camera Link cameras employ CMOS sensors and offer opto-isolated GPIO for triggering and strobe output, pixel-binning and region-of-interest modes, and user-configuration sets for custom default settings. The 2.2-Mpixel model outputs images at up to 280 fps; the 4.1-Mpixel version outputs images at 150 fps. www.ptgrey.com. Module inspects 3-D packages The F30 module from Rudolph Technologies can be used for edge inspection of 3-D stacked packages during manufacturing to ensure that trimmed wafer edges do not have hairline cracks or mechanical flaws. After wafer thinning, the module may perform a frontside inspection to verify that all temporary bonding material has been removed; a backside inspection ensures that the thinning process did not damage the surface. www.rudolphtech.com. Large-format camera works in SWIR range Sensors Unlimited has introduced  the SU640KTS large-format InGaAs high-resolution snapshot video camera that operates in the shortwave infrared range (0.9 microns to 1.7 microns) at 30 fps. The Camera Link camera has a 640x512 pixel array with a 25-µm pitch. It features non-uniformity corrections, automatic gain control, and adjustable automatic contrast enhancement. www.sensorsinc.com.