Durr develops AGV for the paint shop of the future

Automobile production of the future is moving away from the conventional production line and toward modular workstations. An important feature in the upcoming change is flexible automatic guided vehicles (AGVs). Dürr, one of the world's leading mechanical and plant engineering firms, has developed an AGV specifically designed for paint shops as a new solution for more intelligent production.

EcoProFleet combines tried-and-tested industrial components with innovative ideas, like a new energy storage concept. The AGV is ready for operation around the clock – without breaks for charging at the power outlet.

Enabling a modular painting process
Whether it’s small cars or SUVs, with electric motors or combustion engines, the range of vehicle models painted in a plant is ever increasing. Manufacturers want to be able to easily integrate new vehicle types into the production process. This desire for flexibility and scalability is pushing linear production to its limits.

The necessary migration to modular production is requiring manufacturers to rethink production logistics. In rigid painting lines, the process time for all car bodies depends on the model that requires the longest time in the individual stations. This results in waiting times for other bodies, which can be avoided with a modular process. Instead of transporting bodies using conveyor technology laid rigidly in the ground, they are moved independently and in parallel formation between work decks, like spot repair or polishing, and intermediate storage. 

According to Durr, EcoProFleet enables a modular painting process in which different processing times for the car bodies no longer cause waiting times. The resulting cost benefits are all the greater the more different and individual the bodies are constructed and painted. Downtimes caused by sudden malfunctions are also reduced to a minimum, since AGVs can be redirected to a different workstation or a different painting booth. "Scalability and flexibility are becoming increasingly important in paint shops. With EcoProFleet we have designed the first AGV for paint shops and thus created an important enabler for these requirements," says Jens Reiner, Director R&D and Product Management at Dürr, describing the significance of the new development.

First AGV designed to meet paint-specific requirements
EcoProFleet is the first AGV that has been specifically optimised for the needs of paint shops. Its paint- and solvent-resistant platform is just 225mm high. This low height means that the AGVs can go under all typical workstations and conveyor systems in order to drive a car body into a workstation, hand over, or pick up bodies, and thus work together perfectly at the interfaces. In order to transport the heavy loads, the EcoProFleet AGV is designed with an unladen weight of 850kg in good proportion with the maximum load capacity of 1,000kg. The integrated technology with laser scanner and safety limit speed guarantees a high level of safety.

Intelligent concept for energy supply and control
The energy storage concept with supercap technology enables smart logistics tailored precisely to the painting process. EcoProFleet uses supercapacitors as energy stores, which charge within 1.5 minutes. The charging points are installed strategically in the plant layout where the AGV would be stationary anyway for passing off or picking up a body. This short time-frame is enough to supply the supercaps with more than enough energy for the next section. Compared with a battery-powered fleet, where a fixed number of transport systems always have to be kept plugged into a power outlet for hours, the major benefit of EcoProFleet’s energy concept is that all the AGVs are always on the move and working. This is guaranteed by a sophisticated control system, which is connected to DXQcontrol, the central production control technology from Durr.

Durr says it offers a consistent, intelligent control system across all levels for the use of AGVs in paint shops: the device control for physical control of the individual AGVs, the fleet control for route planning and the higher-level order planning are transparently linked via interfaces. This allows AGVs to fully exploit their potential as a flexible and efficient transport system.