Bosch Rexroth Prepares for Industry 4.0 with Connected Hydraulic Systems

Machine manufacturers are increasingly digitalizing their machinery and expect hydraulic systems to integrate seamlessly with this networked environment. For many years, hydraulic systems equipped with electronics, sensors, appropriate accessories and autonomous controls for the future have now reached the same level as electromechanical drives in terms of automation technology. Bosch Rexroth has introduced a new software wizard to the market that transfers decades of experience in parameter configuration. Thanks to the software that facilitates the commissioning of electronic hydraulic axes, technicians can achieve flawless results within minutes. European machine manufacturers are increasingly digitalizing their machines and expect hydraulic systems to integrate seamlessly with this networked environment. Tasks previously performed with iron and steel valve controls are now being carried out using decentralized intelligence within electronic drive control units. When the customer needs power, they adjust the speed of the drive pump or reduce it to nearly zero. Variable-power hydraulic systems consume up to 80 percent less energy compared to fixed systems. Intelligent Solutions with Decentralized Intelligence Decentralized intelligence and open interfaces are of great importance for future automation solutions. Bosch Rexroth uses multiple-Ethernet interfaces that support all standard protocols in their electronics and hydraulic systems. The next step is to integrate sensors into existing valve bodies. This brings various possibilities with it. For example, during condition monitoring, sensors can record all types of information—from oil quality to heat, from vibrations to cycle changes. Deep learning algorithms provide users with the ability to identify wear before it causes any malfunction, which is one of the most important steps toward preventive maintenance. Intelligent single-axis controls are already responsible for decentralized hydraulic movement in closed control loops. To achieve this, powerful motion control is integrated into the electronics above the valve. Controls without control cabinets are increasingly being used across different markets. Rexroth offers motion control fully integrated with valve electronics and without a control cabinet through its IAC control valve. Using open interfaces such as proprietary decentralized fluid circulation servo-hydraulic axes, it becomes possible to connect fully to the network. Commissioning of axes, pumps and cylinders ready for this configuration is completed with a single assembly that requires the machine manufacturer to only connect the power source and manage communication.

'Plug and Play' for Hydraulic Systems

In the future, valves previously required for motion will be replaced by best-in-class controls. Electric drive positions the hydraulic cylinder only according to the speed of the drive pump. Therefore, hydraulic gears have exactly the same function as electromechanical linear drives. As an added benefit, thanks to all the advantages of hydraulics, they convert the rotary motion of electric drives into linear motion. Progress is more evident in the next development stage, referred to as autonomous linear axes. Special, high-level fluid circuit cylinder groups are ready for commissioning. For this reason, machines operating these axes do not need central hydraulic units. Autonomous axes are connected in the same way as electronic drives. All that is required is a power cable and a machine-controlled data connection. The same software tools used to operate electronic drives are used. Commissioning engineers do not need in-depth knowledge of hydraulic systems because they can simply adjust pre-programmed functions for the machine conditions.

New Design Using 3D Printing

Rexroth offers innovations in new materials and manufacturing technology. 3D printing of cores for cast housings or direct printing greatly reduces energy requirements for functioning valves. While manifold design previously had to account for the divisibility of the manifold tool, this requirement is eliminated with manifold printing. For example, Bosch Rexroth can design a pipe that permits lower pressure losses and improves energy balance. In a valve with a flow of 10,000 liters per minute, a 20 percent reduction in flow resistance results in substantial savings in operating costs.

Hydraulic Commissioning Process Is Becoming Largely Automated

Thanks to Rexroth's new software assistant, you can easily commission electric hydraulic systems without needing comprehensive knowledge of fluid technology. It reduces the initial commissioning of hydraulic actuators and the setting of axis and motion parameters to just a few button presses. Technicians have achieved flawless, robust results within minutes and been able to move the axes. For the initial operation of electronic hydraulic axes, Rexroth transferred decades of experience in parameter configuration to the software wizard. This software wizard guides technicians logically through parameter configuration and prevents incorrect inputs. Even those without any experience with hydraulic systems can quickly and reliably obtain robust results. If the wizard cannot read the information from the electronic board, it queries the components in a dialog. Subsequently, the assistant requests application-specific information such as installation location, masses to be moved and maximum impact. It also calculates characteristic values such as maximum speed, maximum power and natural drive frequency. The software internally considers all properties of fluid mechanics. By entering a linear distance, it creates a nonlinear valve characteristic and balances 'overshoots'. Commissioning engineers are not involved in these calculations; they only work on the physical parameters of the application. Thanks to the suggested parameters, drives can be moved within minutes without risk of impact. Automatic distance detection is also possible for many hydraulic axes. With the commissioning wizard, commissioning engineers can allow hydraulic drives to independently perform monitored movements within specified limits. The intelligent function automatically calculates all internal values without human intervention and allows for manual fine-tuning.