Innovations in robotic grippers from On Robot, Schunk and Cobotect.

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.