Correct machine control system increases profits for customer and machine builder; the five key items
The quantity of electronics and software in each machine is increasing very rapidly and machine control systems are becoming more and more complex. In the past a machine was operated with just an on/off switch, but now machines has many motors, cylinders and sensors. Machines have more features and are also required to work more precisely, more reliably and more quickly. More inputs and outputs have to be controlled and more sensors and actuators are therefore present. The inputs and outputs have to be more accurate to allow the sensors and actuators to work with much greater precision. Another factor that improves accuracy is the data output speed and the response to output values. These cycle times are becoming faster and faster in order to guarantee even more accurate and reliable functioning. The behaviour of these cycle times in real time also has considerable significance. Each of these facets has an impact on the way the machine is controlled.
There are a very large number of new requirements imposed on machine control systems, and it is therefore becoming more and more complicated to assemble them using the right components that are available on the market. The right choices must be made in terms of the speed of the control system as well as correct input and output modules. Some I/Os demand a high level of accuracy, while other I/Os do not. The same applies to data output speeds and settings. If components are used which are available on the market, the specifications of the most demanding I/O is used and the modules are selected on this basis. A large number of I/Os are overspecified as a result of this, which is in turn reflected in the cost price.
The same also applies to the speed of the control system. The process that needs the shortest cycle time is considered. The cycle type is often dependent on the programme size, and some margin is therefore needed. The speed of the control system is selected on this basis, resulting in relatively high costs for processes that do not demand such high speeds.
The communication features of a machine control system are becoming increasingly important because machines have to be able to communicate within ever more environments. Machines need communication in order to create (or reload) their settings, pass on production data, report breakdowns, for preventative maintenance data and for software upgrades. The requirements in relation to this data and the users of the data are often very diverse. Perhaps only the machines in the production line need the machine's status. Breakdowns are dealt with by the service manager and the software is upgraded by an internal or external software department. A number of different communication features are therefore needed. As a result, a control system is often equipped with multiple different interface modules in order to meet these requirements. These different communication features also increase the cost of the control system.
When updating the machine control system, the Human-Machine-Interface (HMI) is also addressed.
Once again this has to be aligned with what users are currently familiar with. It has to be a colour interface that can be operated via touch or swipe, possibly with keys alongside it. The screen must have graphic icons which can express meaning without added text. The user must be able to see the status of the machine at a glance. This also applies to error messages: the machine operator must be able to deal with standard breakdowns him- or herself without the need to appeal to a specialist.

If a machine control system is updated, it is also important to know what will be required in the future. Fraunhofer published a report on these issues entitled “Industrie 4.0”. This emphasises where the control systems market is going and what will be required of machine control systems in the future. One important theme of this report is that we want to remain ahead of competitors in other parts of the world so as to strengthen our existing position.
“Industrie 4.0” emphasises communication features that enable the sharing of production data with other machines in the production line as well as outputs for service and management data. This is not the only focus however: there is still constant pressure on price, time and quality.
My own vision is seamlessly linked to this view. A machine builder has to be able to offer a new generation of machines to customers, resulting in the creation of an even better business case. This business case involves delivering better machine quality, machine speed and machine cost.
It is difficult to find components available on the market that ensure that the correct I/O configuration can be implemented in a way that guarantees the correct speed and accuracy of each
I/O. To ensure that money is not spent on I/Os that are not used or I/Os that are faster and more accurate than is really necessary, a machine-specific solution is a good alternative.
The same also applies when it comes to finding the right control speed, communication features and
HMI. With a machine-specific solution, all requirements can be met and in many cases they can be implemented at a lower cost.
When it comes to software development, the technological choices that must be made are often complicated. It is now possible to choose between different software platforms such as Windows
Embedded, Android and Embedded Linux. There are major differences between these platforms, and different specialist knowledge is therefore also required. These technologies are moreover constantly evolving and knowledge gained today quickly becomes obsolete. Choosing the most suitable software platform and microprocessor is therefore not a simple matter. It is necessary to use platforms specific to machine building that companies have ready-made and are offering in the marketplace.
To do this, the machine must be in serial production. In this discussion, "machine" means all types and derivatives of a specific machine. When configuring the machine-specific control system, the modules are selected in such a way that both the simple type and the most complex type of machine can be implemented. With this approach, the machine's performance is optimised, its control panel is perfectly matched to the user and the right communication takes place with other machines and the outside world.
This approach only works if the machine-specific control system can be implemented using building blocks. Important building blocks here are a Soft-PLC stack based on the IEC61131 standard, an HMI layer, an HMI interface for monochrome and colour, different screen sizes, touch/swipe/keys, different processor cores from low-end to high-end multi-cores and communication modules. Linux is used for the underlying control system: it is a license-free open platform which allows the customer or end-customer to add applications himself. These building blocks can be depicted as follows in a global architecture diagram.

Using these building blocks, a control system can be implemented very quickly to precisely meet the requirements for the machine. As a result, the best possible machine performance is achieved and the right communication features are also put in place. This means that the machine is able to communicate with machines in the line but also with a BackOffice application. Such an application can be used to manage different machines within a production location.
Management of these machines involves both production data (how much is produced, balancing machine load, correct production etc.) and machine maintenance. It is possible to show a summary of running hours and wear and tear on parts if applicable. This makes it possible to prevent machine breakdowns, as well as allowing the service department to work more efficiently. End customers are able to save a lot of money in both of these areas.
This involves a collaboration between machine control, machine data and a back-office application, which is also referred to as an end-to-end application. This collaboration is essential to optimise functioning, and it is an advantage if all this can be supplied by the same company, avoiding discussions over whether a problem is caused at the control or back office level and also allowing cost savings and improvements in quality and efficiency in case of expansion. One important factor is that real expertise should be available in terms of both machine control and back-office application, although these are different worlds in terms of technology.
The end-to-end application can be depicted diagrammatically as follows:

Another requirement for a machine control system is that it should remain available for a long time.
The control system plays a part in determining the image of a machine. Customers should recognise a machine by its image. If a control system is made up of components available in the market, there will be a dependency on the suppliers as for the period they will continue to make them available in the same form. Quality is another area of dependency. Changes in a module are often not reported if the module still has the same features. Nevertheless, such changes can sometimes lead to complaints in relation to specific installations. This is another area where greater control is available when using a machine-specific control system. It is important that the company ultimately implementing the control system offer a guarantee that it will continue to be supplied for as long as the control system is being purchased. If a component ceases to be available, it must then be replaced by an equivalent component and the new configuration tested in its entirety, including testing in the field. This means carrying out a full check, even at the component level, to ascertain whether there are any changes and if so what tests are needed. In short: the control system will continue to be available in the exact same form for as long as the machine producer requires it.
Summarising all the items that have been mentioned above, Fraunhofer indicates in “Industrie 4.0” that we can only stay ahead of the competition by adding new features and above all by making use of communication features. These new features demand a more extensive machine control system as well as communication with a BackOffice. All this has to be achieved at a lower cost price. The
R&D department of a machine builder will then be able to determine the precise specification of the machine control system that is needed. This will eliminate the need to think in terms of the limitations imposed by components available in the market, and instead enable us to develop what is really needed for a state-of-the-art machine. The five key items for this are:

1.
Right I/O configuration in terms of speed, quantity, precision, local/remote
2.
Optimised HMI for the application
3.
Application standardisation and freedom to expand
4.
Communication features
5.
Cost price
For more information, please contact Arjan Kleiboer, Business Development at ICT Automatisering
Nederland B.V. ICT stands for Industriële Computer Toepassingen (Industrial Computer Applications).
The company has been active in the field of industrial automation for over 36 years. The vertical
Machine&Systems is specifically aimed at the machine control market.