The end of the cage age
© Schaeffler
October 2020

The end of the cage age

Cobots, the smaller, more agile siblings of gross-motor industrial robots, are making a name for themselves. The specialists at Schaeffler have found a way to make this new generation of automated workers perform faster and with greater precision.

A shop floor employee assembles a smartphone, assisted by a robot that hands parts to him or holds the component, freeing up the worker’s hands to do his or her job. Should a hazard arise, the machine stops in time to prevent an accident. It is even able to learn from its mentor – the human – by observing them on the job.

The magic word here is cobots – short for collaborative robots. Working alongside humans, they’re designed to assist and to handle increasingly complex routines – today on the factory floor, tomorrow in workshops, logistics, operating rooms and even in offices. Many manufacturing companies are pursuing new paths, upgrading or transforming their operations. Especially when it comes to repetitive, tiring and physically strenuous jobs, cobots can take over some of the tasks and enable employees to concentrate on more sophisticated process steps. Another advantage of cobots: They’re suitable for automating small-batch production down to batch size 1 – in other words highly customized production runs. The classic industrial robot, which performs repetitive, staccato-like movements, segregated from the human workers in a cage or behind acrylic glass, is clearly at a disadvantage compared to a robot that can collaborate. In Industry 4.0, the traditional robots are losing importance.

The end of the cage age
Intelligence integrated: Cobots not only work directly with human beings, but can also learn from them autonomously© KUKA
Tailwind: a driver for Industry 4.0

With annual sales increasing by 50 percent, the cobot market is already growing faster than that of classic industrial robots. “We can enhance this dynamic market with highly specialized capabilities,” says Ralf Moseberg, Vice President, Industrial Automation, where innovations for various sectors are being developed. “Robotics are an important driver for Industry 4.0 and a central element of our diversification strategy,” says Moseberg. Our experience and know-how in the field of precision manufacturing and the automotive sector can be transferred into this new, competitive field.

A case in point: Schaeffler recently launched a double-row conical thrust cage needle roller bearing for articulated-arm bearing supports. To date, such applications have mainly relied on crossed roller bearings. Schaeffler’s new conical thrust cage needle-bearing solution enables an increase in the number of load-bearing rolling elements, resulting in greater rigidity. Consequently, the robot manufacturer can select smaller bearing sizes, thus saving design space and reducing weight. The movements of the articulated arm gain precision and speed, making the production process significantly more efficient. Additional benefits of this design principle include enhanced sealing performance and avoidance of grease seepage, thereby reducing contamination of the production environment. Schaeffler’s 70 years of experience in needle bearings are brought to bear in this solution.

Sales of $24 billion

are expected in the worldwide cobots market (arms, add-ons, software) by 2030. With an annual growth rate forecast of 28.6 percent, cobots represent the fastest-growing market in robotics.

Source: ABI Industrial Collaborative Robots Market Tracker

Extended capabilities: cobot optimization

The precision, strength and agility of cobots are highly dependent on the gearbox solutions employed. The gearbox is, after all, at the heart of any cobot. With its DuraWave RTWH series precision gearbox, Schaeffler sets new standards. As a result, the robot is able to perform smooth, controlled movements. This design makes the cobot practically maintenance-free and allows its lifecycle to be prolonged. Another Schaeffler innovation makes cobots mobile: Thanks to a range extender, cobots travel on a linear path to various workstations as needed. As a result, smaller cobots can be used for tasks that are close by, for instance, and other cobots can be reserved for remote requirements where they must travel further. Using plug & play connections, cobots can easily be integrated into existing production environments. And this is just what robotics customers – like all customers – are looking for: solutions that offer easy integration, without the need for major conversions.

On the safe side

How Schaeffler uses modern robotic and control technology to enhance the safety of existing plant and equipment.

Even though cobots are gaining ground, heavy-duty industrial robots, when properly used, continue to play a role in the modern world of work – not least of all in the area of occupational safety. A perfect, award-winning example: the forge at Schaeffler’s Schweinfurt location, where an industrial robot assists employees working in conditions of high heat. Whereas in the past, components with a weight of up to 300 kilograms (660 lb) and a temperature of about 1,200 degrees centigrade (2,200 °F) had to be manually placed into the press, this is now done by a robot, which also forwards the components to the next process step. Safety light curtains monitor the hazardous area. The technical challenge in this case was to optimize the control electronics in a way that would ensure trouble-free permanent operation in spite of heat radiation, smoke, scaling or flames due to flash fires. The Wood and Metal Occupational Insurance Association honored Schaeffler with the “Smart Fox” safety award for the plant’s superior work safety.

Schaeffler Schmiede© Schaeffler
Right from the RoboLab: up-and-coming tech

“Schaeffler will not become a full-range supplier of cobots and lightweight robots. However, we are planning to be an important partner in this market in a few years with solutions for bearings, components and sub-assemblies,” says Moseberg, explaining the strategy that is being pursued by his unit. “The fact that we use our solutions in our own manufacturing operations – in keeping with a time-tested Schaeffler tradition – is another unique selling proposition,” he adds. With a worldwide network of 75 plants, Schaeffler obviously has considerable in-house demand. In Herzogenaurach and Schweinfurt, some 50 cobots are already being used in operations that include parts feeding, assembly processes, quality assurance and logistics.

In addition to developments in Germany, Schaeffler has been operating its “RoboLab” in the Japanese metropolis of Yokohama since 2018. There, specialists are focused on developing mechatronic solutions for a new generation of robot arms. Having a presence where a particularly large number of robots are at work is obviously an advantage for Schaeffler. Asia is the fastest-growing market for cobots, and Japan is the cradle of robotics. 75 percent of the robots used worldwide are “Nippon Made.” They not only handle a growing number of functions in industrial operations, but also pick up the slack in a country that is suffering from a labor shortage, primarily caused by demographic change. Personal assistant robots are part of everyday life in Japanese stores, schools and nursing homes, and the island state is home to as many as five manufacturers of world renown: Fanuc, Mitsubishi Electric, Yaskawa, Kawasaki and Denso.

774

industrial robots and cobots per 10,000 industrial workers in South Korea: No other country has a higher “robotic density.” However, in terms of numbers, China (154,000) is by far the largest market for robots, followed by Japan, the number one robot manufacturing country (55,200), the United States (40,400) and South Korea (37,800).

Source: World Robotics Report 2019

The end of the cage age© Schaeffler
Kinetic talents

A rising level of automation and higher production volumes presuppose reliable robotics. Articulated-arm bearing supports from Schaeffler are decisive in determining the load-bearing capacity, dynamics and precision of robots – and thus make a significant contribution to increased productivity.

The ideal solution for any movement
The end of the cage age
  • <strong>Precision gearbox (2) </strong>For use in robot articulated joints, Schaeffler offers silk-hat-type speed reduction gears, also known as speed reducers. Due to the functional principles of strain wave gearing, high gear ratios and correspondingly high torques are achieved, combined with a relatively lightweight design. The new RTWH precision gearbox from Schaeffler is characterized by clearance-free operation, high positioning accuracy, compactness and long service life.
    Precision gearbox (2) For use in robot articulated joints, Schaeffler offers silk-hat-type speed reduction gears, also known as speed reducers. Due to the functional principles of strain wave gearing, high gear ratios and correspondingly high torques are achieved, combined with a relatively lightweight design. The new RTWH precision gearbox from Schaeffler is characterized by clearance-free operation, high positioning accuracy, compactness and long service life.
  • <strong>Range Extender (3) </strong>For linear travel of cobots to various workstations, Schaeffler offers a plug-and-play-ready linear system (range extender). It contains both the mechanical and electrical drive technology with customized interfaces. The Schaeffler range extender is optionally available with a tooth belt or ball screw drive up to a maximum travel distance of 18 meters (60 feet).
    Range Extender (3) For linear travel of cobots to various workstations, Schaeffler offers a plug-and-play-ready linear system (range extender). It contains both the mechanical and electrical drive technology with customized interfaces. The Schaeffler range extender is optionally available with a tooth belt or ball screw drive up to a maximum travel distance of 18 meters (60 feet).
Goodbye to awkwardness: a graceful colleague

Many of the robots produced so far lack fine motor skills. There’s still plenty of development potential in this area. The specialists in Schaeffler’s RoboLab are optimizing the interaction of precision joints and sensors to enable them to operate in the micrometer range. For this purpose, a sensor system integrated in the flexspline has been developed for the new DuraWave precision gearbox. It enables torque to be captured precisely where it is generated and to thus provide cobots with a kind of tactile sense. For instance, when a cobot touches a human who is standing in its vicinity, the sensors are able to capture the change in torque and to immediately stop the system.

Increasingly attractive: affordable and safe solutions

In this context, connectivity with smart software and the artificial intelligence that moves the mechatronics is important as well. Just like a human being uses diverse senses simultaneously and interlinks individual perceptions to create a total picture in the brain, a cobot can perceive, analyze and respond to a variety of events by means of multimodal sensing. This is advantageous, especially in applications involving complex movements and unpredictable events. Schaeffler’s objective in this context is to enhance the safety and collaboration between humans and machines while reducing costs and making the solutions available to a wider market. The goal is to make cobots attractive for small and medium-size companies as well.

The end of the cage age© Schaeffler
Proven success: pilot projects

Obviously, all this can’t be achieved without strong partners. Schaeffler’s Industrial Automation business unit collaborates with universities, research institutions, start-ups and established companies in the fields of microelectronics, software and production technology. Renowned manufacturers are already relying on Schaeffler’s expertise. The robot arms are currently being tested in pilot projects like smartphone assembly and pick & place operations. Schaeffler’s experts have also had initial success in having cobots analyze returned components. The cobot automatically removes the parts from a box, takes a picture of them and puts them back into the box. This reduces defects and enhances manufacturing quality. In view of these developments, Ralf Moseberg has no concerns about the rollout of cobots leading to a large-scale loss of jobs. He even expects the use of cobots to enhance the working conditions for employees. This is an additional side effect that drives him and his colleagues.

Oliver Jesgulke
Author Oliver Jesgulke
How cobots are transforming the industrial world is a fascinating topic for Oliver Jesgulke. However, at home, he’s so far chosen not to use little helpers like robotic lawn mowers and vacuum cleaners. For him, the busy assistants are just tripping hazards and pose a risk to hedgehogs just like to his toddler.