Smart cameras check diode shapes
Surface-mount diodes often need to be inspected to ensure the integrity of the epoxy resin that houses them. If the injection molding is not complete, then the device will not be rectangular. These inspections are usually conducted by technicians, but the quality of the encapsulation can only be subjectively assessed, and the inspection task is both monotonous and error-prone. To automate this process, PRIMCE, a Spanish manufacturer of printed-circuit-board equipment, has developed a vision-based system that uses a manipulator to place three copper carrier strips that each hold 24 diodes in front of three Pictor smart cameras from Vision & Control (Suhl, Germany; www.vision-control.com). The three cameras are mounted on a single block, with a working distance to the strips of 450 mm.
After the diodes are inspected for irregularities, the position of diodes with defective injection moldings is sent as ASCII code to an Omron (Schaumberg, IL, USA; www.omron.com) PLC via a serial interface. This ASCII code contains the position of the device on the carrier strip. A cutter, controlled by the PLC, then cuts out the defective diode. Images of the copper carriers are displayed on a single monitor screen by merging them using a video splitter, enabling the operator to observe all 72 diodes simultaneously.
Vision-guided robots to package nuclear waste
Nevada’s Yucca Mountain site is under study as the US national repository for commercial and government spent nuclear fuel and radioactive waste. A critical element in considering the site for such purposes is the integrity of a remotely controlled waste package-closure system (WPCS) that permanently closes containers of nuclear waste before final burial. At present, a prototype of the closure system is under development at the US Department of Energy Idaho National Engineering and Environmental Laboratory (Idaho Fall, ID, USA; www.inl.gov).
Each waste package uses two containers, one nested within the other. Package sizes vary, and new and modified remote-handling equipment will be needed because of the radiation involved. The WPCS is being developed by Battelle Energy Alliance (Columbus, OH, USA; www.battelle.org), an organization that recently contracted with Braintech (North Vancouver, BC, Canada; www.braintech.com) to supply the vision-guided robotic software to control the WPCS remote handling system. Guided by a radiation-resistant camera, this system will move robotic tools between storage locations and the waste package. The software will determine the 3-D location of each tool and the waste-packaging station in the nonfixtured environment of the closure cell.
Vision and SPC check banknotes
Approximately 10 billion Euro banknotes are now in circulation, with 14 printing plants in the Euro nations printing 3.6 billion new banknotes each year. Typically, these banknote-production presses are sheet-fed and run at approximately 10,000 sheets per hour. To achieve constant quality levels, vision systems must inspect security features such as variations in inks and substrates, foil patches and microperforations, and numerous print fonts and sizes, all applied in multiple stages over several days.
Parvis Systems and Services (Milan, Italy; www.parvis.it), a developer of visual inspection systems for industrial process control, has built the Proxima inspection system to address this printing challenge. The Proxima can perform measurement and statistical process control (SPC) operations on individual banknotes or sheets during printing operations, and total inspection and sorting at the final stage. The movable, self-contained inspection system can be inserted into the printing press or set in a separate inspection station.
Vision market continues growth
In its annual report, Machine Vision Markets: 2004 Results and Forecasts to 2009, the Automated Imaging Association (AIA; Ann Arbor, MI, USA; www.machinevisiononline.org) found that the industry has continued its overall recovery from the 2001-2002 recession with considerably higher sales of components and systems, but with declining prices on a per-unit basis. The 2004 worldwide end-user market was approximately $8.1 billion, including sales of OEMs and system integrators, a 23.4% increase over 2003. The end-user market in North America was approximately $1.9 billion, for an annual growth rate of 16.1%. Average annual growth in North America from 2000 to 2004 was 3.3%, while Europe experienced a 14.2% annual growth rate and Japan an 18.8% rate. Total worldwide end-user revenue is expected to grow to approximately $15.7 billion by 2009. The complete 350-page market report is available from the AIA.
Photogoniometer characterizes light and color
Controlling the color and gloss during the final stages of manufacturing is difficult, especially in products that feature deeply textured surfaces and metallic or interference lacquers. To obtain a comprehensive characterization in a single measurement, Radiant Imaging (Duvall, WA, USA; www.radiantimaging.com) has licensed from Philips (Eindhoven, The Netherlands; www.philips.com) a photogoniometer technology called the Parousiameter, which characterizes optical appearance by measuring the full hemispherical light distribution in a few seconds. Instead of using a standard movable photodetector, the Parousiameter uses a cooled CCD system with no moving parts. With 80-dB dynamic range, the tool can measure reflection and transmission and self-luminous devices such as LEDs and LCDs. It has raw data-output modes in the form of 16- or 8-bit images in TIFF format, text files, and BRDF files.