Since the 1990s, robot capabilities have advanced in speed, accuracy, and repeatability, along with payload. For example, the Kuka KR 1000 Titan six-axis articulated-arm robot lifts a 1000-kg (2200-lb) payload over a 3202-mm (126-in) maximum reach with repeatability up to 0.2 mm (0.008 in).
Enhancements in machine vision enable non-structured tasks such as bin picking. Force-feedback technology has given robots a sense of touch. Combined with offline programming as part of a complete manufacturing simulation package, not only are robots cheaper to buy, but they are also easier to program. While there is still a place for traditional transfer technology, use of robots is growing. They are used in ever more complex operations. These operations include fixturing whole car and truck bodies. They also are used in material removal such as deburring or drilling, as well as the more traditional welding and painting applications. Pushing their capability into the computer numeric control arena, Stäubli announced in September its RX170 HSM robot specifically designed for machining, with a high-speed spindle integrated directly into its forearm.
This is forcing suppliers of end-of-arm tooling and support equipment to adapt as well. “There are really two areas of change in robotic automation that is forcing us [as suppliers of tooling] to adapt: increasing robotic payload and advances in control technology,” said Walter Saxe, Automotive Business Development Manager for Applied Robotics. “Our tool-changers need to hold those higher-payload end effectors. Where we used to have to pick up a 200-kg weld gun, we are being asked today to pick up a 500-kg car body.”
Saxe added that higher reliability, easier repair ability, and inherent reliability (think fewer parts) are ongoing improvements to their equipment.
Significant advances in controls technology have forced suppliers of end-of-arm tooling and support equipment to adapt as well, according to Saxe.
“There is no universally preferred controls technology globally,” he said. While some customers use the DeviceNet standard, others use Profibus, ethernet, or fiber optics.
“The controls system tracks if welds are done properly, if the vehicle body has indexed into the weld station, or if the weld gun has failed among other functions. It collects, gathers, and controls what is going on in the plant,” Saxe explained.
Applied Robotics developed an electronic module that interfaces with these different control system protocols. “To meet our customers changing controls requirements, we are working to develop a more flexible system to accommodate the disparate controls technologies that are used today,” said Saxe. “We expect to release something truly unique and innovative in the first quarter of 2009.”