Flexibility and safety go hand in hand with 3D cable beads for robots

With the far-reaching digitization of business processes, the tasks of robots in production environments are only expanding. Thus, they form dynamic "work forces" for welding, painting, soldering, palletizing ... to list just a few possible tasks. These 3D applications involve continuous rotating and turning movements, and then cable tracks such as igus' triflex R, which safely guide and protect the robots' cables, are needed. Meanwhile, the specialist from Cologne, Germany, continues to invest in the development of innovative solutions, including the triflex TRX cable bead with a unique telescopic mechanism and the i.Sense TR.B sensor, the world's first system for breakage detection in 3D cable beads.

Revolutionary 3D cable beads

Safe cable routing is essential for industrial robots to operate reliably. After all, a robot's cables must be able to withstand numerous bending cycles and loads due to torsion and tension. With the triflex R, igus supplied a round cable bead with a defined bending radius for the energy supply in industrial robots, which protects the cables even during dynamic turning and swiveling movements. This 3D cable caterpillar is therefore used in a wide variety of applications. In the past, to avoid loops caused by movements that could interfere with the operation of the robot, retraction systems on the third axis were used. However, the axes of robots offer less and less space, so the specialists at igus started looking for an alternative solution.

"Based on the triflex R, we developed triflex TRX, a four-dimensional cable caterpillar, in which the retraction system is already integrated. This space-saving solution can be attached directly and compactly to the third axis of the robot. It rotates within itself, lengthening and shortening spirally, as is the case with a telescopic extension and retraction system. This allows compensation of the cable track length of up to 40%," says Jörg Ottersbach, head of the e-chains business unit at igus.

"To do this, we use a screw connection system in the unique mechanism and on an integrated rubber band, which constantly brings the links back to their starting point. The retraction force can also be adjusted via this band. The cables are spirally integrated into the cable caterpillar and are also safely guided through the movements by that caterpillar. In addition, the cables and hoses are secured in the center of this triflex TRX so that they remain in place when the cable caterpillar is pulled. Compared to other retraction systems, 83% saves weight and requires less than half the space. In this way, the robot's performance is further optimized, and since no additional retraction system needs to be provided, the costs are also significantly lower."

Sensor for intelligent fracture detection

igus' R&D department and product management also thought about the rapid detection of problems in the cable tracks. After all, breakages must be avoided at all times, as this leads to production stoppages and late deliveries of finished products, and thus ultimately limits the company's profit margin. Thus, a new, cost-effective solution was developed to detect breakage at the 3D cable bead triflex R in real time: i.Sense TR.B. With a limited investment, customers can now make their robotic systems more sensitive sustainable. 

"The i.Sense TR.B sensor connects directly to the customer's PLC control, with no additional software cost. If a link in the cable truss breaks, the system detects the change in cable length and a digital signal is sent to the system controller. Real-time break detection allows for immediate maintenance. Individual breaks will thus never lead to unplanned downtime. The added value of this real-time monitoring of the status of cable tracks is therefore considerable," explains Richard Habering, head of the smart plastics business unit at igus. 

"We are constantly working to further optimize our products in terms of quality and durability. To this end, many tests are carried out in our laboratory. The combination of the flexible triflex R 3D cable bead with high tensile force absorption and the i.Sense TR.B sensor makes it possible to safely guide and protect robotic cables - thus significantly extending their service life. Maintenance also becomes more sustainable, as the user does not have to replace products unnecessarily or prematurely. Moreover, in the event of a breakage, the sensor can be reused after a correct emergency stop." ■