Automation Industry Association

Advances in communications technology have certainly made the world a smaller place. Sophisticated mobile phones and personal digital assistants (PDAs) with ever-increasing functionality and e-mail make it possible for many people to access documents at any time in almost any place. Such quick access to information has resulted in increased efficiency in many aspects of business life.

Automation companies are constantly innovating to leverage the benefits of such developments in an industrial environment and have developed solutions that give mobile access to a factory's process control system.

In most industrial plants, control systems are used to monitor and control many device parameters, for example, the level of a tank, the temperature of a fluid in the process or the opening of a valve. Most plants have one or more centralized control rooms and in each room, the user typically has access to several operator stations with large 20-inch monitors. Using the graphical user interface of each station, the operator can supervise a process by means of graphical representations of real world devices. The system returns alarms and events from these devices as well as giving the operator device control, eg, motor stop and start.

It is often necessary for operators, process engineers and service personnel to visit the production area for troubleshooting, commissioning of new system parts or during scheduled inspections, etc. Problem solving usually means that the person in the production area has to be assisted by a person in the control room. Communications are carried out by means of a walkietalkie, telephone and even by miming or simply shouting. Naturally, the risk of miscommunications is quite high.

This dependency can be significantly reduced, or even eliminated, if staff could move around within the factory and still have access to the tools and information they need. Think of the time saved trying to explain complicated instructions and the reduction in downtime when a problem occurs.

This potential has now been realized with the development of a solution that allows factory employees mobile access to the plant's process control system. The solution now termed 'the mobile control room' is perceived as a new and future way of working.

Challenges faced

Mobility can be achieved in a number of ways, ranging from a laptop via Tablet PCs and Pocket PCs to a mobile telephone. From a human-computer interaction perspective, mobility in general, and the use of small devices in particular, has some special requirements. Because of their size, pocket PCs and telephones cannot display the level of detail seen on 20-inch monitors in the control room. For an operator working in the production area, such detail is not really necessary. Engineers are therefore faced with the challenge of filtering out the most important and relevant information available in the controlroom to a normal operator and structuring it for use on a mobile device.

With this in mind, the designers focus on the display of dynamic information such as the state of a device, measured values and set points, while using only graphical symbols for all devices.

The solution

A good solution gives a mobile user (eg, an operator or service technician) real time access and control to all devices in the control system by means of hand-held computers and wireless communication.

A process portal server acts as:

• A connectivity server to access data from the process controllers (through OPC).
• An access server for mobile clients (by means of the Microsoft Internet Information Server IIS).

This solution ensures the following functions are available to users:

• Process overview: This allows the user to monitor the state of his process.
• Process control: Using faceplates, the operator can interact with the process.
• Alarm list: The user is always notified and can evaluate and acknowledge whenever there is an alarm.
• Device search: The operator can do this using an object request function.

Technical overview

When the device is turned on, the mobile user is automatically connected to the local area network (LAN) using, for example, wireless LAN (WLAN), Bluetooth or GSM/GPRS/3G.

• The client software requests information using an http-type request. In fact, the graphical user interface is in the form of a web page.
• The server in turn queries the process controller(s) for dynamic information using OPC.
• The user is then presented with continuously updated real-time information.

One of the key objectives when designing such solutions is to ensure that they are 'terminal independent'.

The User experience

In a highly automated environment, operators very often become so dependent on operator stations that it becomes nearly impossible for them to move outside the control room. Yet, highly automated processes require inspection and control by a person on the move. When a problem has been detected in this way, quick and effective action means equipping the operator with tools that enable the execution of various tests that give immediate visual feedback.

Adopters believe operators and service engineers should have the proper tools available to enable them to carry out their jobs effectively. In addition, they carry a reputation for adopting new technologies, and off-theshelf type Pocket PCs with relatively few teething problems.

Users observe that:

• It is very important to realize that mobility means a new way of working. Work processes and thus the tasks the user performs, must be changed.
• From a design and implementation point-of-view, it is important to focus on what functionality is really needed and what can actually be accomplished on a small device. In addition, it is critical to maintain the same look-and-feel as a normal control system. The mobile device is after all a complement to operator stations.

Benefits

The benefits users experience include the following:

• Problem solving is somewhat easier and quicker when operators are next to the machine and are able to run the equipment manually.
• Access to the alarm list has been of vital importance.
• Production is quickly back to normal after certain disturbances.
• Problems are spotted earlier, thus improving preventive maintenance.
• The commissioning and testing of new process equipment is easier.
• There has been a very noticeable reduction in communications traffic between the factory floor and the control room.
• Operators found the use of the standard voice record function, available on most Pocket PCs, to record memos very useful.

In the long-term, some companies believe this technology will minimize or even eliminate the need for special purpose panels (for manoeuvring). Minimizing the use of local panels, buttons and indications could save costs in a number of different aspects including electrical design, installation and commissioning, actual material, programming and maintenance. In fact, when it comes to the design of a new process section, the 'mobile control room' concept can reduce costs over the complete life cycle.

Functionality in the future

In the not too distant future, it is anticipated that the following functions will become part of a mobile control room:

• Video transmission to enable communication with a remote expert when problem solving.
• The use of video sequences to demonstrate work procedures, for example for certain maintenance tasks.
• Access to maintenance systems in order to create, receive and finalize work orders.

Some companies strongly believe that use of this type of technology will help them remain very competitive. They see new technology as a means of improving work processes and therefore productivity and efficiency.

- Pierre Öberg, Christoffer Apneseth