For manufacturing companies, assembly is usually the most time-consuming part of the process chain and therefore very cost-intensive. At the same time, monotonous, physically strenuous work steps are often even harmful to the health of many assembly workers. At first glance, it sounds like a perfect solution for everyone: Flexible, safe robots are used as cooperation partners to relieve employees and save time and costs.

But it's obviously not that simple. "Almost every robot manufacturer now has a collaborative robot for human-robot collaboration - HRC for short - on offer; a robot that does not need to be separated from humans by a safety fence, but can literally work 'hand in hand' with them. But they have hardly been integrated in a meaningful way in industry to date," says Sebastian Blankemeyer, research associate at the Institute of Assembly Technology at the Production Technology Center of Leibniz Universität Hannover (PZH). He refers to a data survey conducted by the Institute for Industrial Engineering (IFaA) in 2016, which mentions just 100 HRC systems in Germany. Blankemeyer continues: "Hans-Georg Krabbe, Head of ABB Germany, stated in 2016 that collaborative robots account for less than 2% of the global industrial robot market." Why is that?

This question was also posed by a call for proposals from the Federal Ministry of Education and Research. The 'SafeMate' research project, which Sebastian Blankemeyer is currently designing and carrying out with Assem Oubari and Dennis Pischke, two PZH colleagues from the Institute of Production Systems and Logistics (IFA), has been funded within this framework since the beginning of 2017. With a total of nine partners from industry and using real-life scenarios, the three scientists want to develop a guideline that will make it easier for companies to decide to use a collaborative robot and, if necessary, support them in implementing it. The results should be available by the end of 2019.

Extremely important: acceptance and safety

When companies consider whether HRC could be a solution for them, they are primarily concerned with two issues - safety and the question of acceptance. Ultimately, according to Blankemeyer, it is always a question of weighing up the costs and benefits: If the effort required to ensure the safety of employees is perceived to be very high, this is a strong argument against the use of HRC. However, possible reservations on the part of the workforce who are to work with the new non-human colleagues are considered to be at least as high a hurdle. In short: "If the assembly workers reject HRCs, their use will fail," says Blankemeyer.

Assem Oubari expresses a similar opinion. His conclusion after the first employee interviews for SafeMate: "Hardly anyone in the workforce says 'We think it's great'. It's usually only the bosses and production planners who say that". Oubari sees this as confirmation of the sentiment he perceived during his time as an industrial engineer in industry - before joining the IFA in early 2017, he worked at Volkswagen for five years.

In total, the scientists are asking the participating partner companies for 'three and a half perspectives', as Dennis Pischke explains: "We are talking to the people who will be working with the collaborative robots, the production planners and the decision-makers." The 'half' perspective is due to the works council, which is also involved, but ultimately represents the position of the employees.

Team player or job destroyer?

The trio responsible for the SafeMate joint project (from left): Sebastian Blankemeyer from the Institute of Assembly Technology, Assem Oubari and Dennis Pischke (both IFA).

© Institute for Assembly Technology PZH

Why is acceptance such a big issue if the small collaborative robots are supposed to make assembly work easier? In their project profile, the scientists cite the fear of losing personal responsibility or even one's job as the main reason. Conversely, for Sebastian Blankemeyer this means: "The most important thing is to deploy people in such a way that they have a sensible task; that they do something that challenges them more than placing a component on a conveyor belt." Companies must be aware that the introduction of robots is perceived as a threat by many employees; after all, it is clear to everyone that changes must ultimately pay off economically and that efficiency therefore often takes precedence over employee interests: "People on the store floor say: if a robot comes here, then another one will come too, and then I'm gone."

If companies want to introduce an HRC system, Pischke and Oubari conclude, they need to involve employees in the decision-making and design phases of a collaborative workplace right from the start. "We need simple and user-friendly methods and procedures in order to design HRC workplaces optimally together with employees." The concern that collaborative robots pose a physical danger can usually be countered quite easily: "It's not the collaborative robot itself that could be dangerous to humans," explains Blankemeyer, but adds in the same breath: "However, if I give it a knife in its 'hand', for example, it is of course no longer safe to work with."

Later, a checklist will guide companies through the process of implementing a potential HRC workplace, including with regard to such safety aspects. The project managers are aware that neither such a guide nor a checklist can be created by just thinking about it at your desk: "We want to accompany five very different real use cases during implementation and use them to illustrate how such a process can work."

Nine partners on board

The team of scientists from the PZH was able to gain five application partners for these exemplary HRC pilot projects: Sennheiser, Miele, LSG Sky Chefs, Lenze and Weidmüller. Each of these companies would like to create a collaborative assembly workstation and each has its own specific requirements. The sectors also vary greatly, from consumer electronics to white goods and catering. This is good for the planned generic guideline, which is intended to make valid statements regardless of individual use cases, but with the corresponding diversity also allows additional conclusions to be drawn - from different perspectives and industries.

In addition to the five users, there are four smaller companies - all SMEs - that are driving the research project forward as so-called enablers. "We identified fields in which we wanted to bring further expertise into the project - namely the fields of acceptance, safety, ergonomics, assembly logistics and the human-machine interface," says Oubari. The four 'enablers' - ATN from Saxony for system integration, Innotec from Lower Saxony for safety issues, LivingSolids from Saxony-Anhalt as experts for virtual assembly processes and Youse from Berlin on the subject of acceptance and user-centered design - will take care of the safety concept, the interface between sensor technology and control and an acceptance model for the pilot applications, for example.

To kick off the SafeMate joint project, all partners met at Sennheiser near Hanover at the beginning of January to discuss the overall project. These large meetings will take place every six months. The substantive work then takes place in smaller, user-oriented workshops. In particular, the cooperation between decision-makers and affected assembly employees and the various methods used for this are to be evaluated accordingly. Finally, the guideline will also contain implementation strategies and design concepts as sample solutions.

Learning factory shows fixed HRC workstation

Alongside the guidelines, the project is also creating another way for companies to approach the topic of HRC without obligation. Dennis Pischke: "A permanent HRC workstation will be created in our learning factory and incorporated into the training courses. It will help decision-makers and employees if they can experience aspects such as safety and acceptance first-hand."

The learning factory at the Institute of Production Systems and Logistics, which is to have this HRC workstation, has been offering training courses on lean production and Industry 4.0 for many years. "The questions that employees have about collaborative working will be similar to the questions about lean production: only when you have actually experienced and played through the theory in practice do you develop a real connection to it."