The time of safety cages in manufacturing lines is over. In the factory of the future, machines, robots and humans work freely, hand in hand. To enable the same level of seamless interaction between humans and intelligent transport systems, B&R is the first manufacturer to introduce the concept of human-track collaboration.
Humans continue to play an indispensable role in many production lines. Even in the age of Industry 4.0, manual workstations are the best option for handling many assembly and testing tasks. Humans' intelligence and fine motor skills allow them to quickly learn and carry out complex new tasks. "This was the motivation for defining 'human-track collaboration' as a requirement," says Robert Kickinger, mechatronic technologies manager at B&R.
Whenever humans work hand-in-hand with machinery, safety takes top priority. While there are established safety standards and recommendations for human-robot collaboration (HRC), human-track collaboration (HTC) has yet to be addressed in the same context. This is not surprising. After all, as Kickinger points out: "We are pioneering new territory in this field." To ensure safety at manual workstations along an ACOPOStrak system, B&R makes use of limit values that have been defined for human-robot collaboration in technical specifications and type C standards from related fields.
ACOPOStrak features five core functions that ensure safety in human-track collaboration: Safe Torque Off (STO), Safely Limited Speed (SLS), Safely Limited Force (SLF), Safe Direction (SDI) and Safe Maximum Speed (SMS). In addition, the maximum safety response time of six milliseconds is very short. All together, this makes makes it possible for the shuttles to slow down to a safe speed and exert a safely limited force when in the vicinity of humans. In other areas of the track, or when no one is around, the shuttles travel at full speed and full power.
What really sets the B&R solution apart, however, are the details. "The limit values for safe speed and safe force are not fixed values, but can be calculated dynamically by the safety application at runtime," explains Kickinger. This allows shuttles of different weights to travel at their respective maximum speeds without posing a danger. "We are the first to support manual on-track workstations at this level," says Kickinger.
The safety functions of ACOPOStrak also enable implementation of a safe setup mode. In setup mode, the speed and force limits apply to the entire track. Once humans have left the safe zones, the restrictions are lifted. "This is a significant advantage over all other available track systems," emphasizes Kickinger. Other systems have track elements whose construction allows safely limited speed, but this limitation cannot be changed. It is not possible to switch between safe and high-speed operation.
The extremely short response time make it possible to reduce the size of safety clearances. Even with collaborative manual workstations and safe setup mode, the machine surrounding the track can be kept to compact dimensions.
With the introduction of HTC, B&R expands the range of applications for its intelligent ACOPOStrak transport system and enables short time to market (TTM) with an attractive return on investment (ROI). Leaving complex activities to humans rather automating them allows a machine to be engineered more quickly and ultimately less expensive than a fully automated system.
B&R's safety solution also improves overall equipment effectiveness (OEE) compared to conventional rigid solutions by allowing production to continue even while an operator is working at the manual workstation. With this development, B&R is pioneering a collaborative new future for manufacturing.
B&R presented its intelligent ACOPOStrak track system for the first time at the 2017 SPS IPC Drives exhibition. At a speed of more than four meters per second, workpieces travel from processing station to processing station on independently controlled shuttles. In between are electronic diverters that divide and merge product streams. This gives machine builders and manufacturing companies countless possibilities to set up a fully automated manufacturing systems especially for individualized products.