November 23, 2017

Robotic colleagues


The market for robotics and automation is growing fast. Cobots, i.e. collaborative robots, are a major trend—and are now being used in laser processing procedures too.

In the middle of 2017, the German Mechanical Engineering Industry Association (VDMA) had to correct its forecast as regards robotics and automation: eleven instead of seven percent growth will push the annual turnover over the €14 billion mark for the first time. The figures match the forecast of the International Federation of Robotics (IFR), according to which 346,000 industrial robots were installed around the world in 2017—around 50,000 more than in the previous year.

The shift towards Industry 4.0 is now tangible. More and more companies rely on fully automated, digitally connected processes. In addition to robots, industrial image processing systems now play a key role. Accordingly, demand in the imaging market is growing quickly. The VDMA expects growth of 18 percent. The turnover of German providers alone will then be around €2.6 billion.

Humans and robots work hand in hand

As part of the digital transformation, image processing systems are monitoring quality during production processes. They help to control processes and act as sensitive sensor systems for robots. This is now so advanced that industrial robots are leaving their once-compulsory protective cages. So far, humans and robots were kept apart when working for reasons of safety. Now, however, robots are becoming “cobots”: collaborative robots which work hand in hand with humans.

These cobots are lighter, padded all round and move more slowly than robots in a cage. If there is a risk of a collision with careless human colleagues, they stop within milliseconds thanks to their sensitive sensor systems. Laser scanners and camera systems are replacing the protective fences. With their help, the cobots also remember their actions. In order to program them, their human colleagues move their robotic arms into the desired position using gentle pressure – half a dozen joints ensure the necessary freedom of movement. The cobots then remember these movements and reproduce them without ever becoming tired.

Growing range of applications for cobots

Automotive manufacturers including BMW, Ford and Volkswagen rely on cobots, as do manufacturers in the electrical and electronics sector. The sensitive robots are also taking on physically demanding tasks in the production of power saws and in shipping logistics. Thanks to high-speed 3D sensors, they can also select parts reliably even if they are mixed up. The first providers are equipping cobots with high-resolution 3D measuring systems in order to automate procedures in quality control. Because the large protective cages are no longer needed, cobots can measure components inside machines or work with quality controllers in laboratories.

The Fraunhofer Institute for Laser Technology ILT Aachen is now involving cobots in laser processing procedures. With laser-based tape-automated bonding (LaserTAB), they take over the micro bonding of battery cells and the contacting of round cells with 3D-printed connecting components made of copper. In order to do this, the researchers have equipped a lightweight cobot from Kuka with a relay optical system and a spacer. The latter ensures that the welding locations remain at a constant distance from the lens for optimum focal lengths during the laser welding process.

Micro bonding without laborious positioning

The user can also guide the cobot during the ILT process. This saves the user the difficult task of searching for the focal position and positioning the laser. During the welding process, the cobot not only maintains the exact distance, it also presses the copper connector onto the battery. Thanks to the combination of sensitivity and power, contacting can be achieved without additional clamping equipment. The researchers in Aachen believe that LaserTAB offers benefits where complex components need to be processed with low production tolerances in spite of varying conditions. When partnered with humans, robots become more flexible here but without sacrificing their major advantage: the fact that they can carry out recurrent processes an unlimited number of times and with consistently high quality but without ever becoming tired.