The shift towards electromobility in the automotive industry has placed strain on production and assembly processes. Businesses that produce manual, automatic and hybrid transmissions, for example, are currently confronted with a highly volatile market brought on by changes in technology and fluctuations in sales.
What role can automation play in reducing this complexity? And what are the benefits of automating certain processes in assembly? Can robots and humans work together collaboratively for greater cost efficiency? These were the very questions we focused on in our project with a manufacturer of transmissions.
Selecting processes for automation
During an initial process efficiency audit, we identified processes along the assembly line suitable for automation and specifically, those that could be leaner, waste-free and scalable in terms of associated costs. Typically, transmission assembly is organized in several production areas arranged into workshops or cells, which supply many assembly lines with internally manufactured wheels and shafts. Perhaps the greatest complexity exists in the high variety of suppliers, components, load carriers, and part-specific inserts, as well as the many different types of packaging.
Authors
Jan-Moritz Metelmann
Principal at 4flow consulting
Christian Lieberoth-Leden
Principal at 4flow consulting
Robots, then and now
In the past, complex process requirements and high costs provided a strong argument against automation in assembly. Automated order picking involved industrial robots located in robot cells with standard grippers for picking all types of parts from wire containers. Grippers had to be extremely complex, however, often resulting in total investment costs that were not economically viable. In addition, cycle time requirements were often unachievable.
The story is now quite different thanks to the number of specialized and experienced suppliers in the field of robotics and special machine construction today.
Using a new approach to robotic automation, we focused on reducing complexity by automating only simple and recurring steps along the manufacturer’s assembly line. The key to achieving this was to have people work alongside robots, to carry out any varied and complex processes.
Collaborative robots – working together with people
A cobot, or collaborative robot, is a robot designed for direct human interaction within a shared space. Cobots are the latest technology in robotics and have changed the world of automation. Equipped with sensors that give the robot a sense of “feeling”, the cobot will default into a safety mode if it is interrupted in its work, whereas traditional robots would simply continue working, potentially injuring people.
Using a cobot application, we divided up the assembly line work between tasks that were too complex for the robots – including removing layers of tightly wrapped foil or other types of intricate packaging from the various components – and those more suited to automation.
The robots took over recurring tasks including removing wheel and shaft components from large load carriers and preparing semi-finished products for assembly by placing them on roller conveyors. Additional standardized cobot activities included lifting heavy components or sorting standard items from containers, creating a more ergonomic workplace for the workers.
Open space design and increased efficiency: among the benefits
Several advantages of cobot applications were discovered in the study
Step-by-step implementation
Additional functionalities can be added in a modular manner to make improvements, and at a much lower risk than having to rebuild entire robot cells. This type of continuous improvement also offers the possibility to improve reliability and efficiency by shortening cycle times.
Open workspace design
This enables workers to intervene in situations where cobots require support. Unlike with industrial robots, which must be located behind locked doors to ensure safe working conditions, workers can quickly access cobot workspaces. This also means that they can efficiently support several cobot workstations at once.
Efficiency
With standardized activities performed by cobots coupled with human support, our study determined that the manufacturer required 45% fewer employees to complete the work, as compared to the as-is setup. Furthermore, assigning cobots to standardized activities significantly reduced complexity and waste, leading to an expected amortization period of 3.2 years.
Using cobots, automated parts handling on the manufacturer’s assembly line could be designed with low initial investment and quick implementation time. Among the chief benefits were reduced complexity and increased efficiency: an outcome that serves as a business case and nucleus for further assembly line automation projects.
This is based on the article written by Jan-Mortiz Metelmann and Christian Lieberoth-Leden published in the report: “Robotik”, Number 3 August 2022 by Irgendwas mit Logistik.