What’s New in End Effectors: Higher Payload, Faster Speed and Better Safety

Isaac Maw posted 2017-09-19

Companies such as Universal Robots, Rethink and Kuka are getting good at making safe, easy-to-program and highly precise collaborative robots. But an arm can only do so much without a suite of other components, including controllers, sensors and a tool at the end of it to perform tasks. Deployment of a robotic cell requires integration of all these components.

For end effectors, companies such as On Robot, Schunk and Robotiq offer versatile options. Two-fingered grippers are both mechanically simple and simple to program. Their basic similarity to our human hands makes them versatile for performing a wide range of tasks, including machine tending, assembly and pick and place. Unlike a human hand, manufacturing engineers can choose the right gripper for the job, optimizing for strength, speed or a specific configuration.

On the other hand, human hands are soft and fleshy. This poses a major problem for cobot designers, since sharp metal end effectors can pose a safety hazard. Solutions for this have included foam padding or reducing the speed of the robot, but one company, Cobotect, has an innovative solution using airbag technology.

On Robot RG6: Bigger and Stronger

On Robot is a Danish manufacturer of electric grippers for collaborative robots. They recently launched a gripper for cobots tasked with handling objects of various sizes. According to the company, the RG6 is designed to be easy to install on the arm of a cobot and simple to program.

The RG6 is a bigger and stronger version of the company’s RG2, capable of handling a higher payload. A higher adjustable force (25N to 120N) enables three times higher payload (6-8 kg or 13.2-17.6 lbs.) and wider stroke (160 mm or 6.3 in.). This type of gripper is ideal for manufacturers automating the movement of heavy objects in applications such as pick and place, CNC machine tending, packaging and palletizing and assembly.

The RG6 includes many of the same features as the RG2:

  • Customizable fingertips to fit production requirements
  • Dual grippers support without the need for extra wiring
  • Assisted center-of-gravity calculation that lets users enter the weight of the payload and let the robot calculate the rest.
  • Automatic Tool Center Point (TCP) calculation on how the robot arm moves around the calculated TCP of an object, depending on the position in which the gripper is mounted.
  • Continuous grip indication that allows the gripper to discern any lost or deliberately removed object.

 Schunk EGP25: Smaller and Faster

The EGP series from SCHUNK is a series of compact electric small part grippers. SCHUNK expanded the series with the EGP25, a smaller size which weighs 110g and has a stroke of 3mm per finger. The company has also developed an optional “speed” version of the EGP25. By reducing the internal gear ratio, the speed version exchanges grip force for speed. This gives the EGP25 speed version the ability to open or close in 0.03s. With a grip force of 13 N, it is capable of handling parts up to 0.05 kg. The EGP 25 speed version  is designed for high speed pick and place applications.

Users can transfer the sensor systems used in the SCHUNK MPG-plus to the SCHUNK EGP-Speed, and convert existing systems from pneumatic to electrical operation.

 

Cobotect Airbag System

While human-robot collaboration has come a long way in making robots safer, sharp or heavy workpieces and end effectors are still a major risk. Cobotect offers an innovative solution:


When the robot is stationary, the bag deflates in 0.8 seconds, allowing access to the tool and workpiece. When the arm begins to move, the bag inflates in half a second, insulating sharp objects. The system requires a compressed air supply.

With this system, it is possible to drive a robot at up to 1m/s without exceeding (ISO/TS 15066) safety requirements. This could enable manufacturers to meet safety requirements without compromising speed.

The airbag was presented to the public for the first time in 2016 and won the € 20,000 KUKA Innovation Award at the Hanover Fair 2017.

 

With every innovation in end effectors, the capabilities of robotics in manufacturing continue to expand. For more, check out this article on everything you need to know about cobots.