Data Collection - Spc

FSWorks™

FSWorks™ is the most complete factory floor statistical process control software package on the planet. This feature packed powerhouse software is designed specifically for touchscreen applications such as CimStat™ making it much easier for the operator to enter data, clear messages, depress virtual switches, retrieve spec plans, and on and on.

FSWorks™ even has a Virtual Keyboard and Virtual Keypad from which to enter data. This eliminates the need for bulky keyboards and pointing devices on the factory floor. However, FSWorks™ will function just as well on standard PC's.

The Variable Data Entry screen is an easy to understand layout containing real time bar graphs for virtually any number and combination of LVDT's, digital calipers and dial gauges, Heidenhain Glass Scale probes and analog signals. Along with real time bar graphs, the screen clearly shows actual readings in numeric form and a continually updating graph based on subgroups determined by the operator, supervisor or author of a particular spec plan. The bar graphs also change colors depending on whether the readings are within spec, borderline or out-of-control and offer other visual aids to enable the operator to see, at a moments glance, when the operations are successful or not.

A message center is available to alert the operator of any changes in system status, out of spec readings encountered, etc. The ability to View Reference documents is a feature designed to provide factory floor operators with such things as test procedures, control documents and part drawings during the manufacturing or quality control operations.

Within FSWorks™, an operator can ask for a chart to be calculated and displayed using limits and data resident within variable data entry. Several charting solutions are available including Histograms (shown), Xbar, Pareto and Cu Sum.

Since FSWorks™ can be linked (via standard NIC) to a host PC on the corporate LAN/WAN, it also has the ability to share all data files with the complete FACS™ host package. FACS™ contains modules for report generation, chart generation, spec plan authoring / maintenance and communications conduit.

Closed Loop Control

In this application the operator supplies the machine with raw parts at entry end of the cell and finished parts are removed by a robotic arm at the other end. The cell runs essentially unattended. It makes use of Closed Loop Control, which essentially is a method of making near perfect parts. It does this by automatically positioning a tool on a machine such that each feature on a part will be machined to the nominal value for that feature.

This application calls for monitoring 5 features (characteristics). Three of these features make use of Closed Loop Control. FSWorks is connected to a Fanuc18i machine controller via ethernet. FSWorks does the gauging for the application. Each time a part is made, FSWorks measures the five features in question. If any of these features are out of tolerance, FSWorks sends a message to the machine controller and the part is put in a reject bin. In addition, three of these features have the measurement values monitored a little more closely. The average for the last three parts for each of these three features are held in memory. As long as these averages fall within the control tolerance ban set for these features there will be no offsets sent to the machine controller. On the other hand if one these averages does not fall within the control tolerance ban, an offset will be sent to the machine controller in an amount that is equal to the difference between this average and the nominal value for this feature.

For example, one of the features being controlled is height. The nominal value for height is 12.5 mm. The tolerance for height is 12.45 to 12.55 mm. The control tolerance is 12.475 to 12.525 mm. If the average for the last three parts is 12.539mm an offset of (12.539mm - 12.5mm) or -.039mm will be sent to the machine controller and the value of the height for the next part should be 12.5mm.