Teamwork à la ZKW: humans and robots work hand in hand

Teamwork à la ZKW: humans and robots work hand in hand

After around a year of development and optimization, the ZKW COBOT program has now gone live. The collaborative robot works together with the staff on the production line. While industrial robots are used shielded behind protective structures or safety doors in their own cell, the ZKW COBOT stands free and interacts with the operator. The intelligent machine is currently used to assemble headlight light bars.

The first experiences are promising: teamwork with the smart robot makes the strenuous manual work easier for the employees on the assembly line, speeds up the assembly process by around 20 percent and ensures consistently high production quality. "The COBOT project focuses on efficiency, safety and quality. The collaborative robot is intended to specifically support our employees in production," says Oliver Schubert, CEO of the ZKW Group.

The particular challenge of the COBOT project was not only the implementation of the necessary process technology requirements, but also safety-related requirements. The automated robot application had to be usable without any protective enclosure, safety fence or light grid. The requirement for the collaborating robot was to screw nine screws into a headlight strip within a maximum cycle time of 70 seconds - while observing the safety guidelines for human-robot collaboration. The light strip is inserted manually by the operator into the holder provided. After fixing the component, the operator gives permission for the robot to work using a button. While the operator manually positions additional components, the robot moves to the different positions of the screw holes and screws in the screws automatically. 

Safety first

The biggest challenge in programming the COBOT was to ensure safety for the operating personnel. "We have precisely analyzed and evaluated the possible danger points and implemented them in a safety concept, for example by means of a movable screw spindle. If the robot's sensors or the screw spindle detect resistance or collision during movement, for example, sensors pass this information on to the robot's safety and PLC control. The COBOT then stops or avoids immediately. A normal industrial robot cannot do this," says Christian Blamauer, ZKW COBOT project manager. Notching the spindle mouthpiece requires very little force. The system can immediately detect and defuse any collision that may occur between, for example, the screw spindle, finger and light strip. This development was also submitted to the European Patent Office. The ZKW employee who works with the COBOT also confirms that the system has proven itself in practice: "I don't need to check the work of the COBOT, I trust the robot implicitly. We are a good team, I save myself the strenuous, manual screwing in of the screws."

The benefits of human-robot collaboration outweigh the investment costs. Human-robot collaboration helps to increase the efficiency of manufacturing. Because robots and operators work in parallel. In addition, quality can be further assured due to the increased level of automation. The integrated scanner records the serial number of each component. This makes it easy to trace faulty batches. “In the future, further work steps in production, such as the handling of components, could be supported with the COBOT,” says Oliver Schubert.