Light and flexible rotating energy supply ensures gentle cable guidance to the gripper
Pick-and-place robots are increasingly important in automated processes, such as assembly lines. With its EXPT, the automation specialist Festo offers an exact and dynamic solution for this. Operating at up to 150 picks per minute, the robot works continuously. For this, safe and gentle feeding of the cables to the gripper had to be guaranteed. The unique feature—a rotating additional axis—led to increased wear of the cables. With a unique energy chain for tight installation spaces and dynamic applications, including a rotation module, the cables are now safely guided at high rotation angles
Problem
Festo SE & Co. KG is a leading provider of automation solutions for processes and entire production plants. The manufacturer also includes its universal parallel robot, “EXPT,” in its extensive product portfolio. The tripod-based pick-and-place robot works with high performance and precision and manages up to 150 picks per minute. Its design and control system enable flexible and cross-application use, enabling convenient implementation in applications with several robots in the production line.
An A5 axis was to be implemented at the lower end of the robot, where the gripper is located, enabling the gripper to rotate quickly and precisely. A particular challenge was guiding the cables to the rotating axis safely and gently. With a high number of cycles and continuous operation, 360° rotations in less than a second, speeds of up to seven m/s, and accelerations of up to 60m/s2, all cables are under a heavy load, leading to high wear.
Solution
For the cable guidance, we suggested a rotary energy supply to the customer, i.e., an energy chain with a reverse bend radius including a rotation module. To be more precise, the cables run in an energy chain of the E2 micro-series. The energy chain, running in a special rotation module, can also achieve the desired high angle of rotation.
The design of the cable guidance enables several advantages for the pick-and-place robot. The extremely lightweight allows the robot to be highly flexible and move quickly, and the failure rate of the cables leading to the A5 axis has been significantly reduced.
So far, there has yet to be a solution on the market for such a cable feed to the rotary axes, which is why a very close exchange characterised the development work between the Festo engineers and our cable specialists. The specific cables for this application were also selected during this collaboration. Among other things, the manufacturer relies on chainflex® control cables for high loads in moving applications. So that Festo can save itself the harnessing, the automation specialist ordered the energy chain directly with the cables drawn in and ready for connection as a so-called readychain.
Profile
- What was needed: E2-micro series energy chain, designed as Reverse Bend Radius energy chain and moving in a rotation module, delivered pre-assembled as readychain®.
- Requirements: gentle cable guidance to the rotating axis with many cycles, under continuous operation, with 360° rotations in less than one second, speeds of up to 7m/s and accelerations of up to 60m/s2.
- Industry: robotics; pick and place robots.
- Success for the customer: The energy chain with a reverse bend radius achieves high rotation angles and, thanks to its extremely lightweight, supports the robot’s high flexibility and fast movements. The failure rate of the cables leading to the A5 axis has been significantly reduced.