A global leader in of car powertrain technology, car chassis technology, commercial vehicle technology, e-mobility and safety technology, ZF has deployed robots as part of its Industry 4.0 strategy implemented at all its locations, including India. This article highlights how this has been done and the spin-offs resulting from automation.
In the recent past, there has been an exponential growth in the field of robotics, especially in the automotive sector. It is growing in importance as a result of the massive demand of highly customised vehicles and is a necessity to meet the constantly changing customer needs. As compared to the highly expensive robots found in the automobile assembly lines previously, economical and flexible machines are now being installed, which are intended to be more adaptive. Here is a case to drive home the point: For Birol Serdar, a production line worker in transmission assembly at ZF, digital networking makes the impossible seem possible.
When he first saw his new assembly workstation in Friedrichshafen’s commercial vehicle plant, his first thought was: “It’s straight out of science fiction!” Transmissions weighing over 650 pounds rotate on the production line as though guided by invisible hands as robots move them into convenient working positions. At any stage in the assembly process, Serdar can find the information he needs on
his workstation’s touch-screens. He’s still amazed: “I have become one with the computer!”
Computer-aided assembly (CAA) is the technical term for the system now in use in Friedrichshafen, Sorocaba and Passau; an example of how ZF is tapping the potential of Industry 4.0. Flexibility is key: Serdar assembles 190 transmissions per shift. Each one is unique, and there are 6,000 possible product variants. This is why he is grateful for ‘Pick-by-Light’, a paperless part-picking solution. During the ‘small parts’ step in the assembly process, for instance, the drawer with the precise part he needs lights up right when he needs it.
The operator assistance system provides information, authorises resources, and helps with quality control. There’s only one thing it can’t and isn’t intended to do: replace people. “When people think of Industry 4.0, they usually assume everything is fully automated. But many operations will still require the human touch – even in the future,” says Dr Nils Macke, head of ZF’s Industry 4.0 steering committee. Birol Serdar isn’t worried that a robot will take his job. “Our products are much too complex and individual for that,” he says.
Back home in India, the Brakes India plant (JV partner of ZF with ZF 49 per cent and TVS 51 per cent) implemented robot operations that have led to a 200 per cent increase in productivity. This system gives an option of running a third shift with minimum manpower deployment and helps reduce the capital expenditure for increasing capacity. The automated press lines with nine presses and end-to-end automation includes feeding the sheet metal to palletizing the finished components. Brakes India introduced robot automation in hazardous MIG welding operations
for the fabrication of brake shoes.
This has eliminated operator fatigue and has resulted in consistent output with superior quality. For electro plating and painting of components, automated transporters or automated conveyors are used instead of robots. Furthermore, the introduction of robot automation in assembly line which works in clean room atmosphere for Slip Control System (SCS) where robots are used for application of wet sealant in a contour and also for staking operation in multiple planes.
Meanwhile, the use of robots also enhances safety. “Safety is our overall goal. All of our processes have to be absolutely safe. Working with heavy machines and air-powered tools requires a lot of power, endurance and accuracy which is done with precision by a robot. As they have sensors, the robots instantly stop functioning if they sense an arm or a finger in their track guaranteeing safety of workers around. Besides this, the new generation of helpers (robots) is designed and built in such a way that they can work side by side with human colleagues. These days there are robots which are padded, and thanks to a sophisticated system of sensors, they can also ‘see’ and ‘feel’, enabling them to avoid collisions with its human co-workers. Robots are also capable of performing complex assembly routines with the highest precision,” informs Dr. Macke.
The Brakes India plant is also considering robots mounted on gantry system for loading and unloading in manufacturing cells for machining heavy castings. They are now in the process of extending robot application for four cells in their press shop to increase productivity and to achieve ergonomics of the operation. This eliminates operator fatigue when handling heavy components. Meanwhile, for the successful implementation of robot automation, design of ‘End of Arm Tool’ (EOAT) is critical and it determines the consistency of the operation. Accessibility to small areas of the product can be achieved by suitable EOAT design. Depending on the profile of the component, ZF decides whether to use magnetic grippers or vacuum grippers.
The big advantage of using robots is that activities which are generally considered mundane, repetitive, dirty or hazardous are the ones where they are used the most. Says Dr Macke, “When we talk about digitalisation in production, we are really talking about enhancing efficiency through intelligent factories with new technologies and the automated exchange of data in real time. But this only happens if we increase our flexibility so we make better use of our existing resources. Even collaborative robots couldn’t replace human beings – but they could help reduce error rates in production. What we at ZF are really interested in doing is empowering everybody in the workforce – regardless of their age or stage – by expanding their skill-sets so they that they are capable of tackling these new challenges. To do this, we intend to further enhance our commitment to training and continuing education.”