Introduction to LabVIEW
LabVIEW (short for Laboratory Virtual Instrumentation Engineering Workbench) is a platform and development environment for a visual programming language from National Instruments. The graphical language is named “G”. Originally released for the Apple Macintosh in 1986, LabVIEW is commonly used for data acquisition, instrument control, and industrial automation on a variety of platforms including Microsoft Windows, various flavors of UNIX, Linux, and Mac OS X. The latest version of LabVIEW is version LabVIEW 2009 which was released in August 2009.
The programming language used in LabVIEW, also referred to as G, is a dataflow programming language. Execution is determined by the structure of a graphical block diagram (the LV-source code) on which the programmer connects different function-nodes by drawing wires. These wires propagate variables and any node can execute as soon as all its input data become available. Since this might be the case for multiple nodes simultaneously, G is inherently capable of parallel execution. Multi-processing and multi-threading hardware is automatically exploited by the built-in scheduler, which multiplexes multiple OS threads over the nodes ready for execution.
LabVIEW ties the creation of user interfaces (called front panels) into the development cycle. LabVIEW programs/subroutines are called virtual instruments (VIs). Each VI has three components: a block diagram, a front panel, and a connector panel. The last is used to represent the VI in the block diagrams of other, calling VIs. Controls and indicators on the front panel allow an operator to input data into or extract data from a running virtual instrument. However, the front panel can also serve as a programmatic interface. Thus a virtual instrument can either be run as a program, with the front panel serving as a user interface, or, when dropped as a node onto the block diagram, the front panel defines the inputs and outputs for the given node through the connector pane. This implies each VI can be easily tested before being embedded as a subroutine into a larger program.
The graphical approach also allows non-programmers to build programs simply by dragging and dropping virtual representations of lab equipment with which they are already familiar. The LabVIEW programming environment, with the included examples and the documentation, makes it simple to create small applications. This is a benefit on one side, but there is also a certain danger of underestimating the expertise needed for good quality “G” programming. For complex algorithms or large-scale code, it is important that the programmer possess an extensive knowledge of the special LabVIEW syntax and the topology of its memory management. The most advanced LabVIEW development systems offer the possibility of building stand-alone applications. Furthermore, it is possible to create distributed applications, which communicate by a client/server scheme, and are therefore easier to implement due to the inherently parallel nature of G-code.
One benefit of LabVIEW over other development environments is the extensive support for accessing instrumentation hardware. Drivers and abstraction layers for many different types of instruments and buses are included or are available for inclusion. These present themselves as graphical nodes. The abstraction layers offer standard software interfaces to communicate with hardware devices. The provided driver interfaces save program development time. The sales pitch of National Instruments is, therefore, that even people with limited coding experience can write programs and deploy test solutions in a reduced time frame when compared to more conventional or competing systems. A new hardware driver topology (DAQmxBase), which consists mainly of G-coded components with only a few register calls through NI Measurement Hardware DDK (Driver Development Kit) functions, provides platform independent hardware access to numerous data acquisition and instrumentation devices. The DAQmxBase driver is available for LabVIEW on Windows, Mac OS X and Linux platforms.
Role of LabVIEW Database in SPC Software
LabVIEW database allows for creating custom applications that interact with real world data or signals. In fields like manufacturing, engineering this is very beneficial, especially where the SPC Software is used. LabVIEW database as part of SPC software ensures that a higher quality is delivered where a process is concerned, in less time and fewer people involved.
It contains several components, a lot of which are necessary for any type of test, measurement or control application. These components include G Programming, hardware support, analysis and technical code libraries, technology abstraction, modes of computation, UI components and reporting tools. While SPC software helps maximize productivity of a process, LabVIEW in SPC Software ensures quick and easy use of the SPC software and also ensures faster processing of data and improve business productivity.
LabVIEW Database Connectivity Toolkit
LabVIEW offers an additional Toolkit called “LabVIEW Database Connectivity Toolkit”. With this toolkit you can communicate with different databases, such as SQL Server, Oracle, etc.
How IntraStage Can Help You?
IntraStage is middleware solution that seamlessly connects all of your LabVIEW testers, legacy testers, and manual entry stations into a centralized LabVIEW database. Once in the database, IntraStage provides off-the-shelf web reports for quality and yield, as well as exporting the data to tools like Excel, Minitab, and JMP. IntraStage also easily ties into enterprise systems, such as ORACLE, SAP and other MES/ERP systems. Now your internal team can develop test databases faster with IntraStage.