However, Sheffield Measurement shop floor CMM's with built in temperature compensation and Single Touch Interface software (STI) permit a much more productive model: measuring parts at the point of production.  This requires only one CMM programmer to develop easy-to use, customized menu-driven inspection programs that allow machine operators to inspect parts right in the production cell along with their regular duties.

This distributed model allows inspection that is "real time" since inspection results are displayed in easy to read graphical pictures that, with a color change, indicate whether the parts inspected conform.  This provides immediate feedback to the operators.

Single Touch Interface includes simple menu building tools for the creation of an easy-to navigate menu system featuring pictorial buttons that run their previously created part programs.  Operators will execute a complete inspection cycle using either touch screen or keyboard and mouse input.  The main menu shows the available inspection routines and utilities, such as calibration and crash recovery.  The menu's are customizable to a user's need.  The simplest implementation would be a single screen that shows a fixed number of available programs that can be run, as shown in the graphic.  However, an almost unlimited number of part programs can be run from a single STI menu, using various techniques for part identification as programmed in the part program.

Other input devices such as barcode scanners can be integrated, for fast and foolproof part identification and part program selection.

STI slideshows can display inspection results using digital photos, scanned documents such as blueprints or screen captures from your CAD software or PCDMIS.  STI can also be used to convey other information besides measurement results, so the STI program developer can use STI to instruct the user as to proper loading procedures, part orientation, clamp closure, etc.

Using STI as individual features are measured, on-screen feature identification icons pointing to the feature are automatically updated with the measured data, and color coded to indicate in-spec (green), warning (yellow) or out-of-spec (red).  The colors can also represent the percentage of tolerance being used which is also customizable.

The operator has immediate visual feedback as the inspection commences if critical features are within spec.  Since the measurement results are included with the part pictures, identification of good and bad parts is a snap as the visual records are kept in a historical file and can be printed.  If any one feature is out of tolerance the entire slideshow indicates that by changing the top title bar RED.

Complete records of each inspection are maintained for future review, including the time, date and operator running the machine.

If the program and slideshow contained numerous slides showing measurement data the user simply presses the JUMP button to move to the first non-conforming feature for easy identification.

Even Inspections that were partially completed or aborted are recorded.  The STI program can also lock users out of accessing any other functions on the computer without the appropriate password, so unauthorized program operation or modification can be prevented.  Inspection results, integrity and security is also maintained by using STI's access restriction.  No modification or deletion of inspection reports is allowed.

Since STI uses all the available features of the metrology software, all the logic and functions of the program can be utilized.

In most cases, such as the five position fixture shown here, some intelligence can be built into the program that allows the CMM to determine if the part is present, and how it should be oriented in the fixture.

In this example, the CMM probe "searches" for the part by slowly approaching the part from the right.  If the probe finds the part within a specified search zone, the probe then moves to the top surface and starts inspecting in a counterclockwise direction (red dashed line on inset).  The customization of the logic in the program is extensive, due to the underlying programming capability.

Another example is the customization of part identification, presence and location using binary hole patterns which are drilled into custom part holding fixtures-- when the program "searches" for the holes, the pattern of holes and number identifies the part fixture (and thus the part program) automatically.  The probe then seeks the part to see if it's on the fixture, seeks the clamps to make sure they're closed, and then commences the inspection.  Any anomaly can either abort the inspection, or provides operator feedback to fix the problem, and then loops the program back to the seek routines.

Once inspection proceeds, results of each inspected features are available in real-time as the program runs.

Because STI is predominantly graphically based, it's language-independent.  This means that no matter how the part program was developed, an STI routine can be created in any language to run it.  With universally recognizable graphical and color representations for good and bad parts, multinationals can create inspection routines that can be developed as local-language STI programs in many languages for use around the world.  STI programs are currently field deployed in many languages, including Chinese, English, German, Korean, Swedish and Spanish.

As mentioned, this is made possible by the combination of STI along with Sheffield's rugged shop floor type CMM's, such as the Discovery II.  We designed Discovery specifically for harsh environments by using machine-tool type recirculating bearings and hardened ways instead of delicate, easily clogged air bearings.  Discovery is moveable, so you place it wherever you need it, whenever you need to.  It runs on 110/220 AC power, so you can plug it in anywhere.  And it's affordable-- it can replace inflexible hard gages or hand gaging methods, since it's computer controlled, and about 30 times faster than manual methods.  Discovery II is a proven technology that has been installed in hundreds of locations worldwide over the last six years.  STI applications drive many of those CMM's, in diverse production environments from automotive parts to electronic components to plumbing fixtures.

STI is a component of Sheffield Measuremax Classic software, and is now an optional module that works directly with PC-DMIS.  Contact Us for details.