Plastics Technology - Dedicated to improving Plastics Processing.
Issue link: http://pty.epubxp.com/i/839458
So-called "collaborative" robots, or "cobots," have captured the imagination of a number of plastics processors who are looking for automation that can operate safely in close proximity to human workers and doesn't have to be locked away behind "hard" guarding. However, these cobots are often compared unfavorably with standard robots in terms of significantly lower speed and payload capacity. That's why there's a trend afoot to make conventional robots collab- orative—i.e., safe around people— without sacrificing high speed and load-carrying capacity (see short. ptonline.com/Kcollabora). One supplier that recently showed off this capability at April's Automate show in Chicago is Staubli North America, Duncan. S.C. At the show, Staubli showed off its new TX2 six-axis articu- lated robots (which also were featured at K 2016 in Dussel- dorf). Sebastien Schmitt, Robotics Div. Manager, explains the significance of this new robot series in terms of five levels of Man-Robot Collaboration (MRC): • MRC-1 is the standard robot setup, inside a cage so that it can operate at high speed with no possibility of contacting a human. • MRC-2 (human contact not desired but possible) and MRC-3 (human contact expected) eliminate guarding but use elec- tronic sensors such as laser scanners to sense when a human approaches. Two safety zones are defined: If a human enters one zone of proximity, the robot slows to a relatively safe speed, so the human can easily avoid it. If a human enters an even closer zone of proximity, the robot comes to a complete stop. What's unique about this setup is that as soon as the human moves away from the robot, it immediately resumes slow motion on its programmed path, and then full speed as the person moves farther away. No reset command is required. • MRC-4 is force-limited operation of the robot, so that it can run fast but stop immediately upon contact without harming the human—or itself if it strikes a hard obstacle, like a forklift. This functionality can be enhanced by covering the robot with a touch-sensitive skin to help it stop on contact. • MRC-5 is the highest level of collaboration, in which a human manually guides the robot arm to achieve precise positioning of the end-of-arm tooling—perhaps in a hard-to-reach area and/ or when the object being handled is heavy or cumbersome. The robot thereby acts as an extension of, or assistant to, the human, but with no limitation in payload capacity. Schmitt says that the innovation in Staubli's TX2 series robots is that they can be programmed to operate in all five MRC levels. Schmitt called the TX2 "the world's fastest safe robot." He noted that these robots come with a new CS9 safety control and have a "separate safe digital encoder" for each axis and an "integrated safety board." The series has six models that handle loads from 2 to 15 kg with a reach of 515 to 1450 mm. To ensure maximum safety, every motion is monitored by sensors and all position coordinates of the robot arm, as well as its speed and acceleration, are recorded in real time. 800-257-8235 • staubli.us Borealis to Build Automotive PP Compounding Plant Austria's Borealis Group (U.S. office in Port Murray, N.J.) will build a dedicated automotive PP compounding plant in North America, part of its strategy to secure a position as a local supplier to automotive OEMs and their tier partners. To be located in Taylorsville, N.C., the plant is to be commercially operational in early 2019. Initial production will consist of Daplen TPO compounds and Fibremod short-glass-fiber PP compounds. The plant will complement the existing Borealis automotive compounding assets located in New Jersey, as well as current production via tolling partners. Some of the company's latest innovations include materials for light- weighting through reduced filler content, improved surface finish and paintability, and grades for chemical or physical foaming and replacement of metal and engineering plastics. 908-850-6200 • borealisgroup.com New Cellulose-Based Engineering Bioplastic At the Chinaplas show in May, Eastman Chemical Co., King- sport, Tenn., introduced Treva, a cellulose-based polymer that is sourced 50% from sustainably managed forests, unlike other bioplastics that are derived from food sources. Described as an "engineering bioplastic," Treva is said to compare favorably in properties to PC, ABS, and PC/ABS blends. It also boasts better dimensional stability than other bioplastics, as well as strong chemical resistance to skin oils, sunscreens and cleaners, suit- ing it to high-durability items that come in contact with the skin. Eastman says Treva provides high gloss and clarity, as well as a "warm" touch and feel and takes color well, allowing for high pigment saturation. In addition, low birefringence eliminates the rainbow effect some plastics experience with polarized light, giving the material some potential advantage in electronic device screens and retail displays. "Your typical bioplastic doesn't have good color, isn't very tough, and doesn't have chemical resistance," said Randy Beavers, regional business director, Asia Pacific and global sales director at Eastman Chemical (China) Co., Ltd. Eastman also praises the material's processing ease in injection molding and extrusion, noting that in a 0.75-mm spiral-flow test, it performed better than PC and PC/ABS, while being comparable to ABS. Eastman sees applications in eyeglass frames, wearable electronics, headphones, housings, cases, and other items with high level of design intricacy. 800-327-8626 • eastman.com New Robots Made Safer Around People—Without Sacrificing Performance 10 JULY 2017 Plastics Technology PTonline.com T E C H N O L O G Y A N D I N D U S T R Y N E W S St ar t ing Up