The goal is for the operators to see and analyze process, quality, and production-related data. Usually a PLC, motion controller, or standard HMI on a machine doesn't have those capabilities, or it is more difficult to add charting and graphing functions. Users want to get a higher level of information out of the machine.
Fischbach said that both smartphones and tablets are each finding different roles and applications. For maintenance and life cycle management, smartphones are being used more because usually the maintenance people have a smartphone as they move around the plant. Some users may want to know about the lubrication cycle, for example, or many different types of preventative maintenance information. Some preventative maintenance information is embedded into the control and is a prime application for smartphones. He said:
If we look at production and quality management, applications move more into the tablet world. The production quality manager can go to a machine and analyze in the palm of his hand the quality of the product produced at the time. If companies make more complex machines, they often embed a standard PC as an HMI and use LabVIEW and the Wind River real-time operating system to create their control system.
Tablets such as the iPad are often viewed as a convenient interface for viewing data to improve management of production and quality functions.
(Source: Bosch Rexroth Corp.)
At the highest level, users are developing a machine control or machine management PC, and then additional solutions targeting the tablet and smartphone. All of these three use cases can be addressed with Open Core because it is scalable. Companies often use Visual Studio and other software development tools, along with the SDKs, which also makes it possible for customers to actually load their own real-time core into the Bosch Rexroth control.
A design goal is to address the efficiency of users creating solutions, making it open to the future by using open standards. The development kits offer greater flexibility, so users can pick tools they are used to working with and the solutions can be customized to a machine builder's requirements. In the past, machine builders developed their own PC-based control but then communicated using a field bus such as PROFIBUS, DeviceNet, or a very specific Ethernet protocol. But now with mobile devices in the mix, the current direction is switching to standard communication using a span of tools like Eclipse, Xcode, Visual Studio, or LabVIEW.
Using the SDK, the user gains easy access to all of the available system variables, calls, and functionality that can be automatically uploaded into the development tool. With OPC, someone needs to create variable maps or import maps, and there is a lot of work required to achieve this level of connectivity.
Mobile web apps
Another approach to creating mobile or web apps has been developed by Opto 22. This solution uses what is called a groov network appliance to interface with the machine control network in a plant, and an integrated set of tools that make it easy for users to develop their own mobile applications. "We are calling groov at a highest level an HDI, or human device interface, because the human is interfacing with any device, any screen size, and any web browser," Ben Orchard, an applications engineer at Opto 22, told Design News. "It's more about the human to the device interface, rather than how the device interfaces the process or the machine."