The requirements in mechanical engineering - whether for handling systems, robot applications or machine tools - always read the same: flexibility, individualization, transparency, availability and efficiency. But that's not all: the digitalization megatrend is also contributing to the fact that machine manufacturers are increasingly required to look for new strategies and solutions for short changeover times, batch size 1 and modern concepts of human-machine interaction. In view of ever faster development times, it is becoming more and more of an art to harmonize these demands and trends with your own company and to derive calls for action for improved processes and future-oriented technologies.

However, without immediately turning the big wheel of problems, from an engineer's point of view it is often the operational innovations at project level that are convincing in a customer-specific application and improve the development of systems and plants. If the approach proves successful, a project-neutral assessment can be made of the extent to which this specific solution can be standardized for other projects with similar requirements.

Distributed intelligence in the form of multiprocessor architectures, for example, is one solution for making production processes more efficient, networked and secure. Intelligent networking plays a decisive role in decentralized, modular machine architecture in particular, as the identification and localization of devices must be ensured during communication - from the field to the office level.

The requirement to map diverse machine types in mechanical engineering and to keep them maintainable also calls for solutions that support market standards such as Ethercat or Codesys, so that the simple integration of components into superimposed line structures is ensured by standard interfaces. This ensures the aforementioned flexibility and openness to be able to change automation structures quickly.

Regardless of whether you are aiming for a centralized or decentralized automation topology or an intelligent mix of both: From a software engineering perspective, an open automation platform allows the machine manufacturer to choose whether a servo inverter is integrated into the machine topology as a simple actuator, as a parameterizable axis or as a freely programmable axis. In other words, hybrid approaches that guarantee the combinability of different system architectures create the necessary freedom in the design.

Multi-talented movement monitor

The coupling of Motion Control with the Android world opens up a new world for motion apps for typical motion tasks such as axis synchronization, print marks, winders and cross cutters.

© AMK

If several axes need to be coordinated on a machine, the factors of cabling effort and space requirements can quickly become cost traps when commissioning several servo inverters. This is because the coupling of many inverters requires more space and also increases the effort involved in connecting the components. In such cases, it is therefore worth considering a multi-servo as an alternative. Compared to single servos, such a solution allows the drive technology to be up to 60 % more compact. In addition, there is no need for wiring, as - as is the case with the 'MultiServo' from AMK - the cross-wiring of the four axis modules and the power supply (DC link, 24 V, real-time Ethernet) is implemented internally in the device.

The dynamic and sophisticated coordination of up to four axes within a machine segment offers further advantages in terms of communication: The response time of the drive control in the MultiServo in relation to the setpoint is many times faster, as there are no fieldbus cycles. The device also interacts with a higher-level controller in real time. The Ethercat CoE profile (CAN over Ethercat) is currently implemented for this purpose; further fieldbus slave connections are planned.

As far as programming is concerned, the MultiServo relies on predefined basic functions that can be customized for the motion task using a teach-in procedure - in line with the motto: configuring instead of programming. The advantage of such a solution can be seen, for example, in the axis control of a delta robot. Normally, the time required here increases if an additional language has to be learned to program the robot.

Sequence control distributes the intelligence

The digitally operating compact inverter modules coordinate the drives in 4-quadrant operation precisely and with high dynamics using integrated motion control. The motion transformation and path interpolation are therefore calculated directly in the inverter and not in a higher-level controller. In the event of a data interruption to the higher-level system, the axes can be brought to a standstill in a coordinated manner in an emergency. Regardless of this, the compact inverter modules can still be networked multifunctionally via various fieldbuses to the higher-level control system.

Last but not least, the integrated motion control creates the basis for a flexible, expandable machine configuration, as a new module can be quickly integrated during the life cycle of a system without having to reprogram it in the central control system. Instead, all target coordinates are specified and the complex calculation takes place decentrally and clearly in the MultiServo. From a transparency perspective, this type of motion control takes the complexity out of the machine - subsystems can be manufactured, tested and commissioned separately.

Functionalities that can be integrated via app

If non-time-critical sequence controls are also integrated into standard mobile devices such as smartphones or tablets, a human-machine interface familiar in the consumer environment can be used on site at the machine. In practice, the complete operation and programming of the system, including motion control, can be carried out on the basis of functionally subdivided apps instead of centralized, extensive and correspondingly complicated engineering environments.

The drive and device communicate via OPC UA - a control world without a PLC is therefore possible.

© AMK

Machine control via smartphone, in which the automation components are compliant with the Android operating system, ultimately paves the way for solving typical motion tasks with standardized motion apps in the future. In combination with the controllers from the A7 series and the 'AMK Cloud Solution', AMK has already put together a corresponding package that links the drive train directly to higher-level IT structures for commissioning and predictive maintenance via these motion apps. In a nutshell: cloud-based approaches for control technology and services will create even more room for creative ideas in the future for hybrid-oriented control structures when implementing complex drive solutions, for example in the field of robotics.

Authors:
Matthias Deuschle is Product Manager at AMK;
Jürgen Rapp is Product Manager at AMK.