DAQ News - Microstar Laboratories http://www.mstarlabs.com/daq.xml Learn more about Data Acquisition (DAQ) from Microstar Laboratories, Inc. Copyright 2006-2007 Microstar Laboratories, Inc. en-us Wed, 08 Nov 2006 13:47:00 PST Thu, 10 Apr 2008 14:45:00 PDT 360 19 20 21 22 23 0 1 2 3 4 5 6 7 Saturday Sunday webmaster@mstarlabs.com (K. Bunzel) webmaster@mstarlabs.com (K. Bunzel) Configurable Sonar Chirp Sound Generation http://www.mstarlabs.com/dsp/sonar-chirp-signals.html?source=rss A typical marine bottom survey in deep water might study sediment accumulations to a depth of 30 meters or so. A "fish" device is trawled below a ship, sending out sonar pulses. These are not simple pulses, rather, they are complex pulses with waveforms having controlled spectral content, and with a well-selected pulse shape. The pulses will echo back from discontinuities between material layers where density changes. By analyzing the distortion and time delay of the return echoes, the properties and dimensions of the layers can be mapped. The shapes and frequency content of the pulses matter. Depending on the study, the signals might be configured differently for best resolution, best directionality, best penetration depth, etc. While DAP boards and the DAPL systems are not complete sonar measurement system solutions, they offer hardware and software features useful for signal shaping, signal generation, and data capture for these systems. A typical marine bottom survey in deep water might study sediment accumulations to a depth of 30 meters or so. A "fish" device is trawled below a ship, sending out sonar pulses. These are not simple pulses, rather, they are complex pulses with waveforms having controlled spectral content, and with a well-selected pulse shape. The pulses will echo back from discontinuities between material layers where density changes. By analyzing the distortion and time delay of the return echoes, the properties and dimensions of the layers can be mapped.

The shapes and frequency content of the pulses matter. Depending on the study, the signals might be configured differently for best resolution, best directionality, best penetration depth, etc. While DAP boards and the DAPL systems are not complete sonar measurement system solutions, they offer hardware and software features useful for signal shaping, signal generation, and data capture for these systems. Click to continue...

]]> Thu, 10 Apr 2008 14:45:00 PDT http://www.mstarlabs.com/dsp/sonar-chirp-signals.html?source=rss Timing for Rotating Equipment http://www.mstarlabs.com/daq/time-rotating-equipment.html?source=rss Most measurements of rotating machines are captured at a set of equal angular increments that span each rotation. To determine angular position, the usual practice is to mount an optical encoder device on the shaft. Optical encoders provide one "top dead center" (TDC) output pulse per rotation, plus a separate stream of pulses at equal angular intervals. The TDC pulse indicates the start of each rotation. For example, engines time their fuel injection and firing cycles based on an angular displacement from the TDC position. Instead of sampling at equal time intervals based on a precision oscillator, your DAP (Data Acquisition Processor) board can use the encoder pulses to initiate sampling action. Depending on the rotation speed, the time between samples might vary, but the sampling locations are always the same. Most measurements of rotating machines are captured at a set of equal angular increments that span each rotation. To determine angular position, the usual practice is to mount an optical encoder device on the shaft. Optical encoders provide one "top dead center" (TDC) output pulse per rotation, plus a separate stream of pulses at equal angular intervals. The TDC pulse indicates the start of each rotation. For example, engines time their fuel injection and firing cycles based on an angular displacement from the TDC position.

Instead of sampling at equal time intervals based on a precision oscillator, your DAP (Data Acquisition Processor) board can use the encoder pulses to initiate sampling action. Depending on the rotation speed, the time between samples might vary, but the sampling locations are always the same. Click to continue...

]]> Tue, 12 Feb 2008 14:45:00 PST http://www.mstarlabs.com/daq/time-rotating-equipment.html?source=rss Online Self-Tuning PID Controller http://www.mstarlabs.com/control/self-tuning-pid.html?source=rss A previously posted note on the Microstar Laboratories Web site describes an experimental PI controller augmented with automatic self-tuning features. Why not a PID controller? This article explains why. It also shows how a classic tuning strategy, unsatisfactory in itself, makes a useful complement to the self-tuning strategy, extending the method to full PID control. A previously posted note on the Microstar Laboratories Web site describes an experimental PI controller augmented with automatic self-tuning features. Why not a PID controller? This article explains why. It also shows how a classic tuning strategy, unsatisfactory in itself, makes a useful complement to the self-tuning strategy, extending the method to full PID control.Click to continue...

]]> Fri, 11 Jan 2008 15:00:00 PST http://www.mstarlabs.com/control/self-tuning-pid.html?source=rss Intelligent Data Selection - A six-part article on software triggering http://www.mstarlabs.com/daq/triggering.html?source=rss First, the basics: what is it, and when does it matter to you? Second, walk through the steps necessary to add software triggering to a data acquisition application on a Data Acquisition Processor system. Third, see how applications can use software triggering to process data in blocks rather than individual samples. Fourth, explore how you can use software triggering to control acquisition on many data channels - perhaps the most common application of software triggering. Fifth, use a DAP board for measurement and control. And, finally, work with the PC host. First, the basics: what is it, and when does it matter to you? Second, walk through the steps necessary to add software triggering to a data acquisition application on a Data Acquisition Processor system. Third, see how applications can use software triggering to process data in blocks rather than individual samples. Fourth, explore how you can use software triggering to control acquisition on many data channels - perhaps the most common application of software triggering. Fifth, use a DAP board for measurement and control. And, finally, work with the PC host.Click to continue...

]]> Wed, 10 Oct 2007 12:14:00 PDT http://www.mstarlabs.com/daq/triggering.html?source=rss Data Reduction: Isolating Information from Bulk Data http://www.mstarlabs.com/daq/reduce.html?source=rss The most common reason for using a Data Acquisition Processor (DAP) board is its extended capacity. But if you use that capacity in the same way that you would use a basic data acquisition device, you will realize only a fraction of the potential benefits. This note is about using data acquisition effectively on a larger scale. The most common reason for using a Data Acquisition Processor (DAP) board is its extended capacity. But if you use that capacity in the same way that you would use a basic data acquisition device, you will realize only a fraction of the potential benefits. This note is about using data acquisition effectively on a larger scale. Click to continue...

]]> Mon, 08 Oct 2007 13:58:00 PDT http://www.mstarlabs.com/daq/reduce.html?source=rss Benchmarking - Throughput Capacity http://www.mstarlabs.com/daq/throughput.html?source=rss Measure tradeoffs between the number of channels, data rates, and onboard processing when capacity requirements conflict. Though embedded processing is often hard to observe and measure, some features of the DAPstudio software make measurements of DAPL processing capacity relatively easy. Most processing commands on a Data Acquisition Processor board - even some intensive DSP processes such as Fast Fourier Transforms - can run as fast as the Data Acquisition Processor can sample. Measure tradeoffs between the number of channels, data rates, and onboard processing when capacity requirements conflict. Though embedded processing is often hard to observe and measure, some features of the DAPstudio software make measurements of DAPL processing capacity relatively easy. Most processing commands on a Data Acquisition Processor board - even some intensive DSP processes such as Fast Fourier Transforms - can run as fast as the Data Acquisition Processor can sample. Click to continue...

]]> Thu, 04 Oct 2007 11:45:00 PDT http://www.mstarlabs.com/daq/throughput.html?source=rss Benchmarking - Response Latency http://www.mstarlabs.com/daq/latency.html?source=rss Measure the time delays you can expect between event detection and the delivery of results. This note describes how to use a Data Acquisition Processor (DAP) board to measure control loop signal propagation delays. Measure the time delays you can expect between event detection and the delivery of results. This note describes how to use a Data Acquisition Processor (DAP) board to measure control loop signal propagation delays. Click to continue...

]]> Tue, 02 Oct 2007 16:22:00 PDT http://www.mstarlabs.com/daq/latency.html?source=rss White Paper: Implementing Automatic Controls on a Windows PC http://www.mstarlabs.com/docs/prcontrolwp.html?source=rss You now can review a white paper on when and how to implement automatic controls on a Windows PC. A PDF version of the complete document is also available for download. You can develop and operate a real-time control system under Windows by using a Data Acquisition Processor (DAP) board from Microstar Laboratories, Inc. Every DAP board includes an onboard processor running a real-time operating system. DAPstudio - a Windows application from Microstar Laboratories - lets you communicate with and control this real-time operating system. You also can do this from third party (or your own) applications. Any software that supports DLL calls can communicate with and control the real-time operating system that runs on every DAP board. There are limitations to PC-based systems like this, of course. The white paper details them. Within these limitations, the approach described provides a reliable platform for the implementation of control methods that would be very difficult or very expensive to deliver any other way. Such systems might implement advanced control methods, require special data analysis, or operate on a scale beyond the capabilities of ordinary control devices. You now can review a white paper on when and how to implement automatic controls on a Windows PC. A PDF version of the complete document is also available for download.

You can develop and operate a real-time control system under Windows by using a Data Acquisition Processor (DAP) board from Microstar Laboratories, Inc. Every DAP board includes an onboard processor running a real-time operating system. DAPstudio - a Windows application from Microstar Laboratories - lets you communicate with and control this real-time operating system. You also can do this from third party (or your own) applications. Any software that supports DLL calls can communicate with and control the real-time operating system that runs on every DAP board.

There are limitations to PC-based systems like this, of course. The white paper details them. Within these limitations, the approach described provides a reliable platform for the implementation of control methods that would be very difficult or very expensive to deliver any other way. Such systems might implement advanced control methods, require special data analysis, or operate on a scale beyond the capabilities of ordinary control devices.

Scope of the White Paper

The white paper points out where you can apply DAP technology and where other approaches may be a better fit. It discusses how hardware affects system performance and how software does. It goes into how to assure response times and how to measure actual performance limits. It covers time-critical and preparatory processing and explores the issues involved in managing complex event-driven systems. It lists different control strategies in common use and describes what to expect when you implement them on the DAP hardware platform. It concludes with examples that illustrate the technical benefits that come with applying DAP technology.

The Next Step

To find out more, take a look at the white paper itself. You can review it online and download a PDF version to refer to later.

]]> Mon, 17 Sep 2007 15:15:00 PDT http://www.mstarlabs.com/docs/prcontrolwp.html?source=rss Sampling Techniques Extend Demodulation Bandwidth http://www.mstarlabs.com/apeng/techniques/highmodulation.html?source=rss It is not unusual for advanced sensor applications to use modulated signals. Sound, light, or electromagnetic signals can be modulated by a high frequency selected according to physical properties to be measured. For example, an infrared laser beam could be modulated by a high frequency and passed through a material. Attenuation and phase shift of the modulated signal will reveal information about the material thickness and density.To get good resolution in measurements, it is often necessary to use high modulation frequencies. This presents a problem when the bandwidths required for the signal exceed the capabilities of the data acquisition equipment. The obvious solutions can become quite expensive. It is not unusual for advanced sensor applications to use modulated signals. Sound, light, or electromagnetic signals can be modulated by a high frequency selected according to physical properties to be measured. For example, an infrared laser beam could be modulated by a high frequency and passed through a material. Attenuation and phase shift of the modulated signal will reveal information about the material thickness and density.

To get good resolution in measurements, it is often necessary to use high modulation frequencies. This presents a problem when the bandwidths required for the signal exceed the capabilities of the data acquisition equipment. The obvious solutions can become quite expensive. Click to continue...

]]> Wed, 15 Aug 2007 18:08:00 PDT http://www.mstarlabs.com/apeng/techniques/highmodulation.html?source=rss Analog Outputs with Isolated Grounds - Simultaneous Updates: No Phase Errors http://www.mstarlabs.com/docs/prmsxb076.html?source=rss You now can design out two serious potential problems - ground currents and phase errors - from the analog outputs in your application. A new analog output board offers high density, enables high channel counts, includes an isolated ground for each channel, and allows simultaneous updates across all channels. Microstar Laboratories, Inc., maker of Data Acquisition Processor (DAP) boards, today announced the MSXB 076 board that includes eight analog outputs, with an isolated ground for every output. Tue, 26 Jun 2007 13:10:00 PDT http://www.mstarlabs.com/docs/prmsxb076.html?source=rss Control Loops Adjust to Process Change - Automatically http://www.mstarlabs.com/docs/prpizst.html?source=rss You know how it goes with control applications: some key control loops require continual tuning. You don't always have time for this, so system performance suffers. But help is on the way. Microstar Laboratories, Inc., maker of Data Acquisition Processor (DAP) boards, now has shown how you can use off-the-shelf components to build a control system that tunes itself. Every DAP board runs a real-time operating system, DAPL, that you control from PC software. A new DAPL command - PIZST, a self-tuning control algorithm based on a variation of the iterative feedback method - keeps your system in full control during the self-tuning cycles, never interfering with feedback processing. You can read all the supporting documentation online, you can download all required software, and you can order evaluation hardware. So you can see for yourself almost right away how you could build into your application a control loop that tunes itself. Fri, 15 Jun 2007 11:40:00 PDT http://www.mstarlabs.com/docs/prpizst.html?source=rss Press Release: Digital I/O for High Channel Counts - Isolated Ground http://www.mstarlabs.com/docs/prmsxb078.html?source=rss If you have concerns about ground currents as a source of noise, and if you need precise timing across many - or potentially many - channels of digital I/O, then check out a new product that addresses both of these issues. A new expansion board from Microstar Laboratories, maker of Data Acquisition Processor (DAP) boards for PC systems, combines simultaneous operation on all channels with a ground isolated from the PC. The new board - part number MSXB 078 - provides sixteen digital inputs and sixteen digital outputs. Eight rack-mounted MSXB 078 boards connected to a single DAP board controlled by a PC give it 128 digital inputs and 128 digital outputs. Multiple DAP boards can work together across a network as a synchronized system that provides you with maybe hundreds of digital inputs and outputs operating simultaneously - and with isolated grounds. Tue, 22 May 2007 17:05:00 PDT http://www.mstarlabs.com/docs/prmsxb078.html?source=rss Press Release: Data Acquisition Case Studies - A Useful Resource http://www.mstarlabs.com/docs/prcasestudies.html?source=rss View several application write-ups that look at a wide range of situations where an engineer has answered the question, "How can a Data Acquisition Processor board help me do what I need to do?" Mon, 23 Apr 2007 13:40:00 PDT http://www.mstarlabs.com/docs/prcasestudies.html?source=rss Technical Article: Ziegler-Nichols Tuning Rules for PID http://www.mstarlabs.com/control/znrule.html?source=rss PID Tuning Rules, Watch Your Step - While many PID control loops are adequately tuned using time-honored heuristic rules, beware of the hazards. Thu, 12 Apr 2007 13:20:00 PDT http://www.mstarlabs.com/control/znrule.html?source=rss Press Release: Sensor Signal Conditioning for High Channel Counts http://www.mstarlabs.com/docs/prscsnetwork.html?source=rss Take a look at sensor signal conditioning packages with data acquisition systems that eliminate all aliasing from sampling and that scale up to acquire data for applications with hundreds of inputs. Wed, 28 Mar 2007 10:31:00 PDT http://www.mstarlabs.com/docs/prscsnetwork.html?source=rss Technical Article: Building PID Controls in Software http://www.mstarlabs.com/apeng/techniques/pidsoftw.html?source=rss Learn how to implement basic and extended PID controls in software. Thu, 08 Feb 2007 17:50:00 PST http://www.mstarlabs.com/apeng/techniques/pidsoftw.html?source=rss Technical Article: Packaging Multiple Commands in a Single Downloadable Module http://www.mstarlabs.com/apeng/techniques/multicmd.html?source=rss Package your processing commands, so that all of the special commands your application needs are installed together. Thu, 08 Feb 2007 17:50:00 PST http://www.mstarlabs.com/apeng/techniques/multicmd.html?source=rss Technical Article: Coding the QDECODE command - State-driven processing in a custom command http://www.mstarlabs.com/apeng/techniques/qdec.html?source=rss Explore coding in depth for a state-driven custom command that processes position encoder signals. Thu, 08 Feb 2007 17:12:00 PST http://www.mstarlabs.com/apeng/techniques/qdec.html?source=rss Press Release: A Clear Path to Windows Vista http://www.mstarlabs.com/docs/prvista.html?source=rss If you install a data acquisition system today on Windows XP, you later can move your application to Windows Vista without any changes to the parts of your application that interface with your data acquisition hardware and related software. Use Data Acquisition Processor (DAP) boards and systems from Microstar Laboratories, Inc., and you can do this. Fri, 02 Feb 2007 12:20:00 PST http://www.mstarlabs.com/docs/prvista.html?source=rss Technical Article: Online Self-Tuning PI Controller http://www.mstarlabs.com/control/selftune.html?source=rss Try this with your ladder-logic PLC - a PI-controller that tests and tunes itself online. Fri, 05 Jan 2007 15:58:00 PST http://www.mstarlabs.com/control/selftune.html?source=rss Press Release: DAPstudio 3.00 Data Acquisition Software http://www.mstarlabs.com/docs/prdstd30.html?source=rss If you need to deliver a data acquisition system quickly and you want to develop a good user interface for it, then DAPstudio 3.00 could help. This upgrade makes development easier for you in several ways: user input controls for run-time application configuration, custom design windows, easily handle multiple log files. Tue, 31 Oct 2006 13:47:00 PST http://www.mstarlabs.com/docs/prdstd30.html?source=rss Case Study: Data Acquisition Critical to Imaging System that Monitors Brain Activity http://www.mstarlabs.com/apeng/redshirtimaging.html?source=rss Learn how a high-speed data acquisition system plays a critical role in an imaging system being used by researchers to monitor brain activity. Mon, 30 Oct 2006 13:47:00 PST http://www.mstarlabs.com/apeng/redshirtimaging.html?source=rss Technical Article: IEC651A - A Processing Command for A-Weight Audio Filtering http://www.mstarlabs.com/dsp/iec651a/iec651.html?source=rss Human Factors in Real Time: Compensate for frequency sensitivity of human hearing in real time, using standard "A-weight" research-grade digital filters. Thu, 05 Oct 2006 13:47:00 PDT http://www.mstarlabs.com/dsp/iec651a/iec651.html?source=rss Press Release: Scalable 16-Bit Data Acquisition - DAP 5016a/527 http://www.mstarlabs.com/docs/pr5016a.html?source=rss If you need easily scalable 16-bit data acquisition or some real-time processing under Windows, use a product with an onboard processor - one that runs a real-time OS you control from software on your PC. Microstar Laboratories, Inc., announced a new mid-range board, the DAP 5016a/527, that includes a 233MHz Pentium CPU and acquires 16-bit data at 500k samples/sec. Optional software lets you create a synchronized network of multiple DAQ boards. Wed, 13 Sep 2006 13:47:00 PDT http://www.mstarlabs.com/docs/pr5016a.html?source=rss Press Release: Just Add Strain Gauges for Single-Box Solution http://www.mstarlabs.com/docs/prdapserver-sg.html?source=rss For networked signal conditioning, simultaneous sampling, and logging, take a look at a network-ready single-box DAPserver 200 system that conditions, acquires, and logs signals from up to 32 strain gauges. Wed, 30 Aug 2006 13:47:00 PDT http://www.mstarlabs.com/docs/prdapserver-sg.html?source=rss Press Release: Simultaneous Sampling on Many Channels - DAP 5380a/526 http://www.mstarlabs.com/docs/pr5380a.html?source=rss For an affordable building block for creating high-channel count systems that sample inputs simultaneously: a new mid-range DAP board, model number DAP 5380a/526, powered by an Intel Pentium 233MHz CPU. An individual board has sixteen analog inputs and can acquire 14-bit data at up to 800k samples per second per channel. The board has been designed to work well in multiples. Fri, 28 Jul 2006 13:47:00 PDT http://www.mstarlabs.com/docs/pr5380a.html?source=rss Press Release: Fast Sampling and High Resolution - DAP 5216a/627 http://www.mstarlabs.com/docs/pr5216a7.html?source=rss When your data acquisition application needs fast 16-bit sampling and significant processing under Windows, check out the latest product from Microstar Laboratories: a new high-end DAP board, model number DAP 5216a/627. Thu, 13 Jul 2006 13:47:00 PDT http://www.mstarlabs.com/docs/pr5216a7.html?source=rss Press Release: Data Acquisition with Onboard Processing - DAP 5000a http://www.mstarlabs.com/docs/pr5000a.html?source=rss When your data acquisition application needs real-time processing and you need to provide a Windows solution, use a product with a powerful additional processor - one that runs a real-time OS you control from Windows. Try the new mid-range board, the DAP 5000a/526, that includes an Intel Pentium 233MHz CPU. Thu, 22 Jun 2006 13:47:00 PDT http://www.mstarlabs.com/docs/pr5000a.html?source=rss Technical Article: Long-Run Engine Testing http://www.mstarlabs.com/apeng/integration/engine.html?source=rss Test Engines with DAP Systems: Combine ordinary measurement, monitoring, and networking features of DAP board systems to make an extraordinary engine test system. Wed, 14 Jun 2006 13:47:00 PDT http://www.mstarlabs.com/apeng/integration/engine.html?source=rss