Automated guided vehicles (AGVs) make a decisive contribution to optimizing processes in intralogistics. They ensure that the right part is always in the right place at the right time. These systems, for which robust vehicles are used, can be in operation for decades and perform their task with unchanged precision. EK Automation shows that this is possible with an appropriate retrofit concept.

"The service life of a system is calculated based on operating hours. For automated standard industrial trucks - i.e. vehicles from well-known manufacturers that we convert for automated operation - we calculate around 30,000 operating hours, which is at least ten years. For special vehicles, which we design and construct individually to meet the special requirements of our customers, we even estimate 60,000 to 80,000 operating hours. This corresponds to a service life of more than 20 years," explains Ronald Kretschmer, Director Marketing & Sales at EK Automation. Despite so many operating hours, the vehicle must work with unchanged precision at all times during this period. At the end of this period, the user does not have to invest in a completely new system. Instead, with forward-looking planning, the existing system can be gradually brought up to the new technical standard and adapted to changing tasks as required.

Mechanical and electronic refurbishment
EK Automation gives its customers long-term guarantees for the subsequent delivery of components. For the transport robotics specialist, however, refit means that components are not just replaced selectively - as in the case of regular maintenance, for example. Instead, the automated vehicles are completely overhauled. The central task is the electronic rejuvenation program: the entire vehicle control system and cabling is replaced. The mechanical rejuvenation includes the replacement of wearing parts such as bearings, wheels, rollers, chains and belts - comparable to regular maintenance. In this way, the vehicles are brought up to date electronically and mechanically - and their life cycle starts all over again.

Reliability must be a given
Three vehicles from a Berlin crematorium recently arrived one after the other for a pit stop at EK Automation in Rosengarten. For more than two decades, an AGV from EK has been placing coffins in the multi-storey storage area in the crematorium's cold store. Here, the three area-moving vehicles from the Custom Move division move forwards, backwards, sideways and crossways in confined spaces. The vehicles specially designed by EK for this purpose are equipped with a lifting mast and telescopic fork. A tray is mounted on the mast, in which the coffins are transported safely and moved to their intended location. After more than twenty years of operation around the clock, seven days a week, a complete overhaul including an update was required. As the original control system is understandably no longer available on the market, the three vehicles were retrofitted with a new control system and the latest safety technology - so that they can continue to do their job as reliably as before for decades to come.

Planning a future-proof system right from the start
To ensure that users do not suddenly have to do without their entire automated material flow for an extended period of time in the course of refit measures, AGV modernization should be carefully planned, ideally right from the design stage. This is because the task is challenging: an overall system consists of vehicles that communicate with each other as well as with higher-level departments. There are no uniform technical standards for a refit in the industry. Every AGV company uses its own components and many new technologies are conquering the market. Not every provider has given sufficient thought to the future-proof use of their systems once they have become outdated. EK considers itself to be ideally positioned in this respect and has, for example, been using a control system for more than two decades that has been available on the market for a long time and has been used in continuously updated versions since 1996. This makes it possible to mix old and new vehicles in existing systems during successive modernization.

A step-by-step refit
The first step in the refit process is the engineering phase, in which a new vehicle control system is designed and prepared. The central control system is usually converted first and then communicates with the old vehicles. These are then brought up to the latest technical standard one after the other. For a certain period of time, the new control system is therefore in operation with both old and upgraded vehicles. At some point, the refit will also be completed on the last vehicle. It is possible that new vehicles have already been gradually integrated into the system during the process. Finally, the layout, i.e. the routing and interaction of the vehicles, can also be optimized as part of the refit.