Hopkinton, Mass. —Control Technology Corporation (CTC), originator of Quickstep State Language for integrated machine control, recently received a patent for an object-oriented programmable controller. CTC's patented technology is a technique for encapsulating the principal parts of an automated machine in objects, and providing each object with a series of actions for controlling it. The result is a simplified programming environment with benefits, such as maintainability, reuse of software, and the ability to achieve a common understanding among users in a manufacturing facility.

Object-oriented programming is systematic coding that enables control programmers to define devices in the software and encapsulate each device with its own actions and characteristics. These encapsulated devices are objects that, once created, can be reused as modular blocks in other parts of the program

By defining a control strategy as a hierarchy of devices, each with its own set of attributes, object-oriented code is built in the same way as the machine works, not the way traditional code is written. This makes it easier for engineers to design a control strategy that will work in tandem with the machine. Because these programs are built with a more compact, associative structure, where a device's attributes are encapsulated with it, the code is easier to understand, maintain, and debug by all project team members. The engineer can easily find devices that need to be worked on in the code, and focus on the details of each device independent of the rest of the system.

Objects may also be programmed with an "understanding" of their operational limits. Any object that violates user-defined limits can generate an alarm and/or automatic remedial action. For more information, visit www.control.com or www.controleng.com/freeinfo.