Controlling the process with distributed multimedia

A. Guha, A. Pavan, J.C.L. Liu, B.A. Roberts
1995 IEEE Multimedia  
The process control industry has many uses for multimedia, from incorporating diverse imaging sensors to visualizing, monitoring, and controlling timecritical processes. A distributed clientserver architecture, together with specialized imageprocessing hardware and a number of commercial products, demonstrates the effectiveness of using multimedia data in a simulated filmcoating process. n the control and automation industry, multimedia's potential outstrips its traditional use. Sources of
more » ... media data I include image data from video and X-ray, and spectral data from infrared, color, acoustic emission, and other optical devices. However, the traditional control room is removed from the world of the process, with a human operator basing decisions on sensor information. In most cases, the information is textual data with some graphical representation, as in commercial supervisory control and data acquisition systems (SCADA). A few modern automated facilities, such as the inspection systems in nuclear power plants, supplement this with video images. The advantage of using multimedia information is its ease of assimilation, which leads to a more efficient and effective operation. Given the lack of integrated multimedia sources, human operators are the eyes, ears, and noses of the control system; they monitor the process and make the critical decisions necessary to run the process smoothly. Increasingly, however, as industry automates the highly complex processes underlying the production of such advanced materials as liquid crystal displays, semiconductors, and composites,' human monitors are not always sufficient. In these instances, accuracy and speed dictate that the con-trol system itself process data from visual and aural sources. While decision making usually implies a human in the loop, many time-critical automated systems use in-the-loop signal or image processing to automate or facilitate alarm management and diagnostics. The need for sensing higher order process parameters impels the development of multimedia sensing for monitoring a process such as alarm detection.? The drive toward using multimedia in distributed systems is fueled by recent technology: new workstations, displays, and switched networks like Asynchronous Transfer Mode (ATM)" that can support transmission of near-full-motion or fullmotion imagery. This confluence of application needs and emerging technologies indicates that multimedia-based closed-loop control systems are becoming feasible for prototype projects such as power-plant visualization and documentation.' At the Honeywell Technology Center (HTC) we developed a generic distributed architecture for building process monitoring and control systems that incorporate multimedia sensory and data information with real-time decision making provided by in-the-loop signal processing. To test our ideas, we emulated a paper-coating process monitoring system using commercial workstations, video cards, and ATM network hardware. Our early success indicates that new control and manufacturing systems can close the loop on visual or spectral information. We foresee many applications for this class of multimedia systems in the process controls industry, including multimedia operator interfaces, intelligent alarms, in-the-loop broadband sensors for analytical measurements, and descriptive history recording for future process analysis. Generic requirements of a control system The attributes of distributed multimedia impose stringent and diverse requirements on the control network and the system as a whole. The attributes that define system requirements are 1. data bandwidth and volume 2. temporal constraints and synchronization 3 . latency 4. priority 5. reliability 6. predictability and adaptability 1070-986X/95/$4.00 0 1995 IEEE
doi:10.1109/93.388202 fatcat:4jzbu7tcorfzvmuqpa2f3pjvdm