Klas Bengtsson 2017-04-26 04:51:13
THE AGE OF INDUSTRIAL ROBOTS IS CLEARLY HERE. As manufacturing moves from mass production to mass customization the flexibility to efficiently change and adapt production becomes critical. Shorter product lifecycles, continually evolving consumer tastes and made-to-order strategies have changed the game for many companies that produce both consumer and commercial products. Once popular, hard automation systems dedicated to one product are cost-effective and deliver consistent quality in low mix, high volume environments. But they don’t have the flexibility of robotic systems that are able to alternate among different products, product sizes and configurations with minimal changeover time. The age of industrial robots is clearly here, with manufacturers in a growing array of industries investing in robotic automation lines that can handle a wider range of products with agility and minimal disruption. VISION GUIDED ROBOTS Machine vision is a powerful tool that can greatly enhance the performance of industrial robots. As markets increasingly demand high mix, low volume production, vision is becoming a more prevalent component of robotic installations as manufacturers strive to integrate the necessary flexibility into their operations. A vision guided robot (VGR) system is basically a robot equipped with one or more cameras that function as sensors that provide information to the robot controller. Based on that information the controller accurately guides the robot to locate a part and perform a task, despite variability in the product shape or form, or randomness in the way the part is presented. The ability for a robot to essentially “see” enables manufacturers to more easily and cost-effectively implement a robot system for flexible, high quality production. NO EXPENSIVE FIXTURES One major cost savings associated with VGR systems is the absence of expensive fixtures that arrange and present parts in a uniform manner to non-vision enabled robots. The cost of these fixtures, which are typically tailored to each specific part handled by the system, can be quite high on production lines that produce multiple product variations and undergo regular changeovers. With a VGR system, moving between different products requires no more than calling up a new program on the vision system, usually accomplished in a matter of minutes. In non-vision systems a product changeover between batches shuts down the line while the fixtures are changed, an event that can take an hour or more. In addition to the lost production time, there is the cost to store, maintain, and physically move and attach the fixtures. QUALITY INSPECTION Robotic vision systems can be set up to perform quality inspection at any point in the process of locating and handling parts. Part inspection can begin once a part is initially located, verifying that it is the correct product and detecting any abnormalities that may cause further damage down the line. In this case the system can discard the part to avoid further, more expensive damage. Vision systems can also inspect a part once the cycle is complete, assuring the value-added process the robot performed was completed within the necessary quality standards. PROGRAMMING ADVANCEMENTS Recent advancements in software technology have made the design, installation and programming of robotic vision systems far easier. For example, offline simulations software can be used to streamline and test a system design prior to deployment. This can assure the most effective system is configured before any components are specified and purchased. When the VGR system is specified and installed, the simulation software can test the performance of a program, and download it to the robot controller once it has been thoroughly verified offline. Such programming software is an important factor contributing to the growing percentage of robotic applications using vision, while helping solve some of the challenges inherent to vision system installation, including: Establishing a common language for the cameras and the production equipment; Designing and programming the robotic and vision systems simultaneously; Training onsite production personnel to operate the system. In the final analysis it is very common that the expenditures associated with setting up a robotic vision system are justified when compared to the resources required to program robotic systems to recognize multiple parts without the benefit of vison.
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