“The success of our customers is a success for us” Issue 9, December 2018
WE WISH YOU
ALL THE BEST
New issue of Spotlight is available with the announcement of the brand new DEWESOFT X3 SP5 and release of the Dewesoft Sound Intensity solution.
DEWESOFT X3 SP5 is already the fifth iteration of the X3 software, and it brings several new and exciting features out of the release candidate stage into the official release spotlight.
Despite being simple, Dewesoft Sound Intensity can be used to determine sound power of small and big devices.
We also present some exiting application notes and other news!
Your Dewesoft team
DEWESOFT X3 SP5 RELEASE
The Dewesoft team is pleased to announce the release of the new Dewesoft X3 SP5 (available in January 2019).
DEWESOFT SOUND INTENSITY
When “Where the sound is coming from” is in question, nothing is as simple and intuitive as our Sound Intensity solution.
RPC® ANALYSIS ON A MULTIAXIS ROAD SIMULATOR
Dewesoft now offers easy interface to MTS Flextest durability test bench saving time, costs and reducing chance of an error
ANGULAR VIBRATIONS IN AUTOMOTIVE APPLICATIONS
Torsional vibrations can have an effective range from negligible low amplitude sounds, to in severe cases broken or bent shafts.
ORDERTRACKING OF GAS TURBINES
Development and integration of a novel design and manufacture technologies for a range of small gas turbine engines up to approximatively 1000 kW to provide aircraft manufacturers with better choice of modern propulsion units.
Dewesoft solutions can be safely and easily used with servo motors, stepper motors, etc. in conjunction with actuators, torque fixtures or other automation devices for control-type projects.
DEWESOFT STRONGER THAN EVER
The world in orange
Mounting plate for a Krypton system.
See which events are coming up
- Cover page
- Product releases
- Application notes
X3 SP5 release
The Dewesoft team is pleased to announce the release of the new Dewesoft X3 SP5. Official release is coming in January 2019.
This is already the fifth iteration of the X3 software, and it brings several new and exciting features out of the release candidate stage into the official release spotlight. As software stability remains one of the key focus points of our development team, we can proudly say that the software version available with the latest installer has passed the most automated as well as manual tests of any Dewesoft installer to date.
Sound Intensity Application
Probably the most important out of all of Dewesoft’s new functionalities is the sound intensity module, as it opens up a brand new application field for Dewesoft. The sound intensity module offers a complete measurement solution, enabling customers to use it for precise noise source location or sound power calculations, without the need for a special environment, such as reverberation rooms or anechoic chambers.
Because of the module’s importance, it is featured in a dedicated section of the spotlight, accessible here.
Map visual control
The brand new map visual control is the perfect solution for vehicle testing visualization. With support for all standard map tile services and an out-of-the-box "Open street map" layer (image below), there is no longer a need for manual image alignment, meaning that users can quickly and easily achieve sophisticated imaging results.
Map visual control
A major focal point of development has been to make the map usable offline, as measurement systems in the field often lack internet connectivity. If you are performing a measurement where an internet connection is not possible or not allowed, you can pre-download a certain region with a user-defined level of detail, so that the map can correctly display tile data even when your system becomes offline. On the contrary, when the system is online and you scroll the map, all layers are automatically downloaded so that they can load faster next time.
Both TMS (Tile Map Service) and WMS (Web Map Service) protocols are supported, which means that you can connect to most free or commercial map tile servers. However please keep in mind that tile server providers often require a license for downloading map tiles.
The map supports multiple layers, so in case you have access to high-resolution aerial images of your area of interest, you can show them as an additional layer, which will provide an even more detailed view. Geo-referenced images are automatically aligned with other layers, which removes any errors that would normally arise from manual alignment.
Layers can also be combined using custom transparency levels, allowing you to perfectly visualize the data, depending on your needs and preferences. For example, you can add the Open street map layer on top of satellite images to add road and street names.
Map visual control 2
Another extremely useful feature that the map offers is trace coloring. You can for example color the path of a vehicle using velocity or acceleration data, giving you a clearer picture and a better understanding of what took place during the measurement. For even more customization you can select one of the standard heat map color palettes like jet, spring, cool, hot, etc. The visual control is also not limited to just one channel source, as multiple objects/vehicles can be added so that you can see the correlation between them. Each object can have its own coloring definition.
All in all, the map visual control has been developed with the intention of seamlessly performing difficult graphical computation and alignment tasks so that users can effortlessly visualize their data and focus on analyzing it instead.
Modal Test Application
Even though the modal test module has already been available in Dewesoft for quite some time, it has received a significant overhaul in X3 SP5. The update addresses a lot of the customer requests that we’ve received, expands the feature range of the module and makes it even easier to use.
The new version allows users to add multiple excitation and response channels simultaneously. Using this option you can easily perform a modal test in all three directions in the same file. When having closely spaced resonant frequencies, customers can use this functionality as a multiple reference method to accurately determine the resonances. The autofill option allows you to more easily and quickly add a large number of excitation and response channels. With a graphical representation of weighting windows for the excitation and response signals, it is easier to set the windows according to your application. In addition to the H1 estimator, we’ve also added the H2 estimator and PSD calculations.
To support all added functions in the setup, the visual control “FRF geometry” also needed an upgrade. Now you can animate the structure in all three directions, manually select excitation and response points, animate complex, real or imaginary data… During the measurement, the identification of response and excitation points is also much easier due to the different colors of the points. An example of the reworked visual control can be seen in the picture below.
Modal test application
Support for Vector CAN FD devices
In SP5, Dewesoft has added support for CAN FD. As Dewesoft devices aren’t ready for reading the CAN FD protocol yet, users are able to do so with several supported Vector cards*, which are used by Dewesoft to acquire the messages, followed by a decoding process in the software. Apart from reading, the combination of Dewesoft X3 and Vector acquisition cards can also be used to transmit CAN FD messages. Acquiring CAN FD data is by no means a standalone application, as the messages can, of course, be used with pretty much any other data source such as analog, digital, video, GPS…
The main advantage of CAN FD compared to the regular CAN protocol is that a CAN FD frame can hold up to 64 bytes of data, while a regular CAN frame can only hold 8 bytes, allowing more data to be transferred over the same network. The bus speed at 8 Mbit/s is much faster compared to the standard CAN with a maximum of 1 Mbit/s.
Support for Vector CAN FD devices
In the message settings dialogue, the DLC can be set up to 64 instead of 8 with CAN. This means that the total length of the message can be up to 512 bits.
Support for Vector CAN FD devices 2
Users will be happy to know that the interface is exactly the same and shared with CAN, meaning that whoever knows how to use CAN in Dewesoft, also knows how to set up CAN FD, which is enabled with a click of a button.
Support for Vector CAN FD devices 3
DBC import/export is supported with CAN FD which makes setting up new channel lists easy and fast.
*The following Vector hardware is currently supported in Dewesoft and can be used for CAN FD: VN1610, VN1611, VN1630, VN1640, VN7600, VN7610. The first Dewesoft device supporting CAN FD will the Krypton 1xCAN, scheduled to come out in 2019.
The newly released Dewesoft version also features a brand new module called “Cursor”, available to all users. The cursor module expands the functionality of the existing “Latch value math” by allowing users to interactively search for level crossings in analysis, as well as find local/global minimums or maximums of channels. These values are marked on the Recorder and XY Recorder visual controls with specially labeled and colored cursors, visible in the image below.
The purpose of the functionality is to enable you to easily find events within a data file and extract values from other channels at that same time. When searching for a level crossing, Dewesoft will linearly interpolate between the two closest sample points, meaning that the extracted values will have a higher precision than just by taking the nearest synchronous or asynchronous sample. Users are also able to define “Cursor pairs”, in which case Dewesoft will automatically calculate the delta values between all input channels as well as the time difference between the two events. If the data file in question contains multiple instances of the same event then users can move the cursor between those events using the "Next prev button", searching for new events in either the left or right direction.
Additional information about the module and its capabilities is available in Dewesoft’s manual, accessible using the F1 context help or using this link.
Export to ASAM MDF
A highly requested feature in Dewesoft’s automotive sector has been the ability to export data to the ASAM MDF format. While Dewesoft already has an extensive list of supported export types, MDF is one of the formats that users have missed in the past. With X3 SP5, that is no longer the case, as the format is now officially available in Dewesoft.
Generally speaking, ASAM MDF is a file format supported by the Association for Standardization of Automation and Measuring Systems, or ASAM for short. The organization is one of the leaders in the field of standardization and its main focus is the automotive and measurement industry. MDF or Measurement Data Format is a binary file format that stores recorded data for post-measurement processing. Dewesoft’s MDF export is written according to version 4 of the standard defined by ASAM, therefore the files created using the export will receive the mf4 suffix.
Export to ASAM MDF
The export is available as an extension and can be acquired either by using the latest software installer or by downloading the extension directly from our downloads section and adding it to X3 SP5 or any newer Dewesoft version. As is the case with any other supported format, the MDF export can be found in the “Export file type list”, marked in the picture above.
Other features and improvements
- Added a prompt for saving unsaved setup file changes
- New setup button in the channel selector in analyse mode for editing mathematic channels within the review tab
- Next/prev button functionality on the Input control display
- Apply action can now also copy the colors of channels
- Added multiple options for handling sample rate divided channels when changing the global acquisition rate
- Exact frequency math now shows the unit of the selected channel's treshold
- Added the acqtime function to the formula, which returns the elapsed time since the start of acquistion
- File size is available as a system monitor parameter
- Changed addons structure so every extension has a separate folder
- PWM (Pulse-width modulation) functionality for the KRYPTONi-8xDI-8xDO and KRYPTONi-16xDO
- Added signal conditioning support for the HD Sirius slices with analog outputs
- Advanced option which can disable hardware sample rate dividers for faster signal conditioning
Newly supported devices:
- KRYPTONi 1xSTG
- New adapters: DSI-V-20, DSI-ODU-TH-T/J/C, DSI-ODU-5A
- New connectors: SIRIUS-HD-STGS-L2B10fs, SIRIUS-HS-STG-L2B10f
- Added 4k and 40k filter options for the Sirius line of products
- Ability to lock amplifier, sensor and channel properties over TEDS
- Optional warning when an empty TEDS is connected
- Support for writing TEDS with USB 1-Wire writer
- Display a warning message if any changes are done and not written to TEDS upon exiting channel setup
- Warning message when the sample rate is adjusted from TEDS sensor
- Support for pausing TEDS scanning
- Order tracking’s FFT bandwith now takes into account the global bandwith setting
- Added phase information for symmetrical components
- Added support for calculating a 3-phase system out of a 2-phase measurement
- Added a QH_H1per calculation
- Included phase-to-Phase Voltages for the 3-phase delta connection
- Supported all energy calculations (positive, negative, total)
- Added subfolders for symmetrical components
Official release will be available in January 2019.
SOUND INTENSITY SOLUTION
WHEN “WHERE THE SOUND IS COMING FROM” IS IN QUESTION, NOTHING IS AS SIMPLE AND AS INTUITIVE, AS OUR SOUND INTENSITY SOLUTION.
DESPITE BEING SIMPLE, DEWESOFT SOUND INTENSITY SOLUTION CAN BE USED TO DETERMINE SOUND POWER OF DEVICES BIG AND SMALL.
- Complies to sound intensity, based sound power calculation discrete points segmentation method (9614-1) and scanning method (9614-2)
- Calibration according to IEC61672
- Quick sound source Identification
- Adapted method for measuring big chillers and transformers
- Reuse existing sound intensity probes from G.R.A.S. and other manufacturers*
- Feature complete sound intensity measurement
- Works on existing Dewesoft hardware
- Future-proof application
- Easy to use and set-up
- Dewesoft quality and flexibility
- Familiar and comprehensive user interface
How does sound intensity work?
The sound intensity measurement technique is a powerful tool used for sound source location, their order ranking and determination of emitted sound power. The method is based on the simultaneous determination of sound pressure and particle velocity using two closely-spaced, face-to-face, phase matched microphones. The sound intensity probe itself must maintain a well-defined acoustical spacing between the microphones and at the same time cause as little disturbance to the sound field as possible.
Plug and play solution with only three connectors that need to be connected, our state-of-the-art SIRIUS mini seamlessly pairable with intensity probes of different manufacturers. Measurement is fully controlled from intensity probe, making it straightforward and agile for the user to conduct.
Portable. Expandable. Adaptable.
Our powerful solution is completely portable since SIRIUS mini can be powered over USB and coupled directly with intensity probe. Moreover, we support 200V polarization voltage on-the-go for the probes that require it. SIRIUS mini features four analog inputs, two are used by intensity probe leaving two additional inputs available for other measurement sensors.
Besides fully supporting existing probes, we offer complete kits with intensity probe supplied as well. G.R.A.S. 50GI-R was chosen for this purpose, as it can cover entire frequency range with provided selection of spacers.
The useful frequency ranges for different microphone spacers are shown below:
Quick sound source identification feature
Depending on the direction of sound waves travel (from microphone A to B or vice versa), Sound Intensity plugin will display different values, either positive or negative as it is moved along the axis of the probe (microphone axis). When the intensity probe is perpendicular to the noise source (located directly above it), the visual control inside DEWESoft X3 will toggle between positive and negative value. As this process is done for the horizontal and vertical alignment of the probe axis, our Sound intensity solution has reliably identified noise source location with state-of-the-art precision.
Sound sources can be located using the direction of sound intensity (SI Live display)
Sound intensity sound power measurement
Sound power measurement is universally recognized method which was established to compare devices for their acoustic properties. It is often assumed that sound power is measured. And certain methods do measure all parameters simultaneously which makes calculation happen instantly as well.
So, the reality is that sound power is always calculated. Depending on the method used, there are limitations. Some methods require anechoic room or reverberation room which imposes limitation on the size of the measured object and considering all the facts, making them significantly more expensive. Intensity based sound power calculation might not be as fast as other methods, but it definitely brings a set of benefits:
- No limit to the object size and shape
- Few requirements for the room or location of measurement (can be done in any sound field)
- Device requiring specific and complex mounting to operate, can only be measured efficiently with Sound Intensity method
- In-situ measurement to check conformance to factory measurement for fast troubleshooting
- Complex devices where there is residual noise and we are interested only in the sound power of a specific machine
Modern measurement techniques and solutions all require a way to ensure quality and compliance of measurement chain. Dewesoft has recently put special efforts in this area. Every Dewesoft SIRIUS model can thus be calibrated according to IEC 61672-3:2013 Class 1. Our sound intensity solution also includes procedures for single frequency pressure accuracy and also Phase calibration of the whole measurement chain using intensity probe calibrator. In addition, we also carry out calibration of octave-band and fractional-octave-based filters according to EN 61260.
Intensity Sound power can be calculated according to two different standards:
Scanning method (9614-2)
Sound intensity Scanning method for sound power determination is on average slightly less accurate from the Segmentation method. The main reason why scanning method comes handy is the speed at which the measurement can be done. This holds especially true for large devices. Dewesoft solution shines with a very clear visual control and on-screen guidance in regards to timing and scanning patterns. The most powerful aspect is the support for the buttons on the sound intensity probe, making it fully operational by a single person. Scanning method is meant to be simple and fast. So, we delivered just that.
Segmentation method (9614-1)
When more time is available or more detailed approach is necessary, segmentation method is the best option. Once an object is measured from all (usually 5) sides, sound power can be calculated. However, with our solution it is possible to do a more detailed analysis of the result. The software maintains the levels for each segment and further sub-segmentation is possible to extract extra information about the device. On top of all this, intensity probe buttons are supported for moving between segments and triggering start/stop of the measurement. Accompanied with a beautiful visual control with overlay on top of the object image, our solution gives an intuitive view of the results and key quality parameters of measurement.
Dewesoft Sound Intensity solution features familiar and comprehensive user interface:
Default Sound intensity plugin display creates a noise map of selected surface shapes, displaying sound intensity values for individual segments in a comprehensive grid, that can be laid over the image of your measured product. Recorded instantaneous sound intensity values for segments are shown in color according to the predefined color scale. Values for sound power of selected segments and surfaces are displayed in frequency domain as a whole or 1/3 octave spectra.
Live Sound intensity plugin display portrays instantaneous sound power and intensity in either whole or 1/3 octave spectra and displays instantaneous overall values for both quantities. Instantaneous directions for individual octave bands are exhibited in the table on the right side of the screen and overall instantaneous direction is written out as well.
Tech specsThe tech specs for the SIRIUSm-4xACC can be found on the product page .
Dewesoft now offers easy interface to MTS Flextest durability test bench saving time, costs and reducing chance of an error
Signal conditioning for an MTS® test bench and high resolution data acquisition for post-analysis with the same instrument
Manufacturers in automotive and aerospace industry typically use different instrumentation for in-vehicle and test bench testing. However, thanks to DEWESoft combining two data buses (USB and EtherCAT®) and MTS implementing the EtherCAT® communication on the FlexTest® series controllers, the DEWESoft R8rt instrument can now cover all of the following:
- High channel count test bench data acquisition,
- Real-time signal processing for load analysis feedback (over EtherCAT®) and
- Compact size high performance data logger for in-vehicle use.
Figure 1 - DEWESoft R8rt with up to 8 SIRIUS amplifier slices can easily be taken out of the cabinet and used as an in-vehicle data logger
DEWESoft SIRIUS slices have already been used in many signal conditioning applications for test bench
instrumentation, but only as a preamplifier with analog output of +-10 V which is used as an input to the
controller analog input stage.
The secondary input stage can now be removed thanks to direct conversion of analog data to EtherCAT® bus inside the SIRIUS instruments. This significantly improves the user experience due to:
- Lower cost, since there is no need for the additional controller analog inputs,
- 2-in-1 instrument, since the R8rt can also be used as an in-vehicle data logger,
- Simpler hardware setup due to less cabling (a single cable from the controller to the R8 rt),
- Easy and fast amplifier setup in DEWESoft X software,
- High-speed (200 kS/s) and high-resolution (160 dB dynamic range) data acquisition with the same instrument that is used for the test bench load analysis feedback.
DEWESoft SIRIUS R8rt combines 8 SIRIUS slices (and the SBOX industrial PC) into a compact package featuring:
- up to 64 Dual Core ADC channels with 160 dB dynamic range or
- up to 128 channels in single-ADC (24 bit) configuration.
With DEWESoft X software running on the high performance SBOX PC (Intel i7 CPU, up to 1 TB SSD drive, integrated 100 Hz GPS ), it can be used as an all-around data logger for in-vehicle use or a test bench data acquisition device. With the latest addition of EtherCAT® backplane, the SIRIUS slices also behave as EtherCAT® slaves in parallel to the standard operation in USB mode.
EtherCAT® protocol as a standardized technology enables hardware combinations from different vendors in the overall solution for the customer. But if the user is to run the test bench and also acquire data to DEWESoft X software, the data from the SIRIUS slices needs to be collected by two master systems: the MTS FlexTest (EtherCAT® master) and DEWESoft X on the SBOX. Therefore additional data bus (USB) is needed besides EtherCAT® to transfer the data at high rate to DEWESoft X. This is achieved in the following way:
- AD converters on the SIRIUS slices run with the rate set in DEWESoft Channel Setup
- SIRIUS firmware copies the sampled data from ADC in real-time to two locations: a buffer for USB transfer and a separate buffer for EtherCAT® bus.
- The EtherCAT® buffer only holds one sample per channel and is constantly updated with the latest values. EtherCAT® master can collect the most recent data at any time.
The exact moment when the EtherCAT® buffer is latched and the data copied to the EtherCAT® bus is controlled by the EtherCAT master, see Figure 2. In this case the time between those samples copied to EtherCAT® bus depends on the EtherCAT® master jitter which can be up to 100 ps.
Figure 2 - Dual mode clocking diagram (SM sync)
The overall system schematic is shown in Figure 7. Test rig actuator control is done with the analog signals
connected straight to the FlexTest. The rest of the input channels that are used for load analysis feedback on the
specimen (RPC analysis) are acquired by the R8rt, stored on the SBOX and available in real-time to the
Load cells and accelerometers are typically used to measure the response of the specimen. The setup of the amplifiers is done in DEWESoft Channel Setup,
see Figure 3. The EtherCAT® Network Information (ENI) file is required by MTS HWI File Editor to be
able to add
EtherCAT® slaves to the hardware configuration (Figure 4). The ENI file is exported from DEWESoft
copied to the appropriate directory to be accessible by MTS software.
Due to EtherCAT® bus bandwidth usage optimization the data from the SIRIUS slices sent over EtherCAT® is raw and unscaled. Scaling factors are obtained from DEWESoft Channel Setup and are exported to a text
Figure 4 - MTS HWI File Editor
file and included in the ENI file for quick import to the MTS Station Manager. The scaled data always represents the same value as displayed in DEWESoft X software: if the user applies custom scaling in DEWESoft, the scaling factor will also change to give the same physical values when applied to the raw data.
RPC® analysis on a multiaxis road simulator
An application of the R8rt was done on a road simulator for testing the durability of car and truck suspension systems. It consists of 4 corners, each having 6 degrees of freedom. 104 analog input and output channels are used by the MTS FlexTest controller for actuator control. Additional 96 channels are used for measuring the response of the specimen to correlate the loads on the test bench to the real road load data. Signals from those channels are acquired by two DEWESoft R8rt systems (each including 6 SIRIUS amplifier slices) and streamed over EtherCAT® to the FlexTest controller.
Figure 5 - one corner of the rig equipped with accelerometers
To compare the performance of the EtherCAT® data transmission to a classical solution used on such rigs (using +-10 V analog output from the SIRIUS to transmit the data to the controller), a test RPC analysis was performed. Three 3-axial accelerometers were placed on one corner of the rig with input channels distributed between both R8rt instruments. An exemplary drive file was played out on the corner and the response recorded by the R8rt's. MTS RPC® Pro software was used to create new drive file that replicated the initial run. There was no difference in performance and convergence of the RPC Pro compared to the classical analog data acquisition.
Standardized technology adapted by multitple vendors always opens up better solutions for the users. EtherCAT® allows more connectivity with the MTS control system while the parallel EtherCAT®/USB technology allows the user to use the same hardware for completely different tasks. EtherCAT® solution for connecting the DAQ system with the controller can also save kilometers of expensive analog cables that are replaced by a single CAT5 cable. At the same time the performance of the RPC analysis is the same as with the analog preamplifiers.
Figure 6 - 2 kilometres of expensive cabling were saved after installing the EtherCAT® DAQ system
Figure 7 - multiaxis test rig system schematics
ANGULAR VIBRATIONS IN AUTOMOTIVE APPLICATIONS
In this application note we talk about torsional vibration, its origins, effects and how we measure them with Dewesoft. Torsional vibration is an angular vibration usually on a shaft along its axis of rotation. Typically occurring for example in electric motor driven systems, steam turbine plants, automotive driveshafts and generally everywhere where there are uneven rotational loads on shafts. Torsional vibrations can have an effective range from negligible low amplitude sounds, to in severe cases broken or bent shafts. To identify and analyse this problematic frequencies we developed several modules that concentrate on machinery diagnostics. In our case we will talk about Order tracking and Torsional vibration modules.
To properly optimise a system, might it be a drive shaft, differential or a transmission we first need to analyse the designed prototype or existing production model for its flaws. With reliable and accurate data gathered from a controlled environment test, we can then redesign the unit in order to implement the changes which will reduce or completely eliminate the problematic superimposed frequencies. The newly refined part is then tested for confirmation of improvement.
We can also use this tools to determine the state of the machine as means of preventive diagnostics or to test long term reliability.
Rotational speed can be measured in many ways. Not all of the methods can be always used, so it's up to us to determine the right sensors for the required job. Usually we measure rotational speed by means of:
- Tacho: A laser or optical reflection from a reflective or a stripped sticker on the shaft.
- Gear tooth: A magnetic response, induced by the hall effect sensor, from a toothed wheel, with a protruding or sunken wedge on the shaft. Sometimes a gear in the gearbox or differential can be used.
- Encoder or CDM: Encoders or CDM’s are mounted on the end of the shaft or by means of toothed belt and provide several pulses per rotation.
Dewesoft supports many different types of sensors directly and others by Event counting or Waveform timing. For example Encoder, gear tooth, tacho and CDM type sensors are mostly predefined, and you only set the input channels to sooth your type of connection. Other types of sensors have to be configured according to the pulse output they provide, so the hardware and the software knows how to interpret the signal.Dewesoft super counters
Counters are mainly used for measuring RPM and angle of rotating machines. Dewesoft super-counters work on a 102.4 MHz internal time base, always, independent of the current sample rate. In comparison to standard counter, which only output whole numbers like 1,1,2,2,3,4, … one sample later, Dewesoft X is able to extract the accurate values like 1.37, 1.87, 2.37, … full time - and amplitude - synchronized! This is done by measuring the exact time of the rising edge of the signal with an additional counter.
Figure 1: Super Counter mode
Basic event counting
Basic event counting is the mode where we can count either falling or rising edges of the signal.
Figure 2: Basic event counting
Gated event counting
Gated event counting is a mode where the counter counts only when the gate signal is high.
Figure 3: Gated event counting
Up/down counting is a counter operation which counts up when the gate is high and counts down when a gate is low.
Figure 4: Up/Down counting
Waveform timingPeriod, pulse width, duty cycle and Two pulse edge separation
Period and pulse-width measurements are similar in function. The period measurement measures the time between two consecutive low to high transitions, while the pulse-width measurement measures the time that the signal is high. The duty cycle is a procedure where the ratio between the high (or low) pulse of the signal and the period is measured.
Figure 5: Waveform timing comparison
In this category we can find: Encoders, CDM, Tachos or Gear tooth sensors. Each of them uses a different style of measurement and has different good and bad characteristics.
Encoder and CDM
Encoder is the most precise in terms of pulses per rotation. Normal span is from 360p / R, to 3600p / R in high end models.
Figure 6: Encoder 360 pulses / 1 revolution
Figure 7: Encoder 3600 pulses / 1 revolution
They are relatively small, precise, tell the direction and have zero pulse. They require to be connected at the end of the shaft or by means of toothed belt. The problem of mounting is the main reason of why they are not used in more applications. CDM is basically the same device but lacks the zero pulse.
Figure 8: Tacho probes
Tachos are optical or magnetic sensors that usually measure one pulse per revolution (1p/R). They are used for simple rotational speed measurements because they are easy to set up and don’t require much configuration. Their disadvantage is bad precision because we don’t know what is happening to the speed during one rotation.
Gear tooth and Striped tape
It’s possible to increase the precision of Tacho type of measurement by adding reflective or inductive surfaces. This will increase the precision of measurement but at the same increase the complexity of of installation.
Figure 9: Gear tooth sensor
Figure 10: Striped tape sensor
If we further expand the configuration by cutting one or more teeth from the sprocket, we get a zero pulse position and can now calculate the exact angle. Usually we use a 36-2 or 60-2 configuration, for good sensitivity and resolution. In case of striped tape sensors a zero pulse must be 3 pulses long. This is achieved by cutting the tape so we start and end with a black stripe and if necessary paint or cover the remaining gap.
Measurement and analysis is done completely within Dewesoft software. This lets us combine and synchronise multiple different kinds of measurement at once. For example if the drivetrain in a car is tested, we can monitor the engine through OBD, transmission input and output with gear tooth sensors, road conditions with a camera and speed and position of the car with GPS. The software is pc based and can be run from a stationary computer, laptop or our portable SBOX data logger solution. Counters on Dewesoft Sirius hardware run with 100 Mhz which allows us acquisition of an 60-2 Gear tooth sensor at 40.000 RPM.
In our case we can use the speed provided by the counter and derive the acceleration from it. Angle in radians is calculated from Counter angle. Angular velocity in radian is calculated from rotational frequency and then derived to get angular acceleration in radians.
In Dewesoft different types of measurements are divided in Modules. Configurations and calculations dependent on the type of measurement are displayed once we open the module. In this paper we will concentrate on Modules: Order tracking and Torsional vibration.
For Order tracking we need a source of signal Input and a rotational frequency source. Typically we use Vibrational acceleration or Angular acceleration for input signal and one type of encoder for rotational frequency source. In the modul we then setup the kind of measurements we want to make, be it run up, coast down or both, number of calculated harmonics, resolution etc.. If we want to control the run up/down, we can do so by using an analog output and Function generator module.
Results can be visually displayed in different 3D graph in respect to Order or FFT,
Figure 11: 3D graph of Orders vs. Speed
Figure 12: 3D graph of Frequency vs. Speed
and in views like Solid and Line(X or Y axis).
Figure 13: 3D graph in Solid
Figure 14: 3D graph in Line (X axis)
Figure 15: 3D graph in Line (Y axis)
In Torsional vibration we measure the angular difference between two encoders, in other words twist of the shaft.
Figure 16: Representation of torsional twist
Accuracy of this measurement is greatly dependent on the accuracy of the rotational measurement. If we have sufficient pulses per revolution we can accurately see angular velocity.
As soon as we are finished with acquisition of our data, we can switch to Analyze mode. In Analyze mode we can:
- Add mathematics, filters or other signal processing functions and recalculate the results.
- View all measurements
- Print results
- Export selected data in many different formats (Excel, Matlab, Text/CSV…)
In analysis mode it is also possible to add Math functions, and recalculate the signal to display results. It is possible to post-synchronize video files from, for example an action cam or a smartphone. The display can also be changed to sooth the needs of analysis. Results of the analysis can be printed or exported to one of many formats supported by Dewesoft.
Flywheel speed measurement
By measuring the timing of injector pulses we can see the fire order of the engine and compare it with the speed fluctuation of the flywell. With this measurement we see the smoothness of the engine and can determine the source of unwanted irregular angular accelerations.
Figure 17: RPM fluctuation on flywheel in idle
If we measure during run-up we see fluctuation of RPM while the engine is under load. Order tracking further broadens the possibilities to see which frequencies grow through change of RPM.
Figure 18: RPM fluctuation on flywheel during run-up
Figure 19: Primary sensor Angular acceleration
Dual mass flywheel isolation measurement
Dual mass flywheel is a machine designed to provide a constant rotating energy from a non linear source. This used to be done with a conventional flywheel, that would use the force of inertia to compensate for engines lack of power during the combustion cycles. Normal flywheel design lacks the possibility to dampen out violent torques or unwanted vibrations, but is simple in design and relatively cheap to manufacture. The dual mass flywheel is a more complex machine and thus more expensive but offers great vibrational damping.
Figure 20: Dual mass flywheel
Selecting the right flywheel for the drivetrain is therefore extremely important. It must be matched to engine and
the drivetrain for optimal effect.
For analysis of performance a measurement in real conditions must be done. The measuring equipment consists of two counter inputs with two rpm sensors, 4 current sensors connected to Low voltage inputs and one CAN input for engine monitoring. RPM sensors are located on the primary and secondary side of the DMF. Rotational speed is measured on gear tooth wheels that usually have 100+ teeth with 2 or more missing for zero reference. The angular acceleration of each side is calculated from the rotational speed and inputed in Order tracking (Figure 20 & 21) to calculate and isolate the 2nd order of both sides (Figure 22).
Figure 21: Order tracking Prim. Angular acceleration
Figure 22: Order tracking Sec. Angular acceleration
Figure 23: 2nd orders of Prim. and Sec. Angular acceleration
From this two orders the isolation between primary and secondary side of the DMF can be calculated (Figure 23) and analysed to see the flywheels damping efficiency. Current sensors are each connected to an injector so that we can compare the time of fuel injection to the change of angular acceleration on the primary side of DMF. Measurements are taken in 2nd, 3rd, and if possible 4th gear to determine the characteristics trough different loads.
Figure 24: Dual mass flywheel Isolation
Expansion of the system is also possible. By using the gear position information from CAN, defining some triggers and programming a short sequencer, we could make a setup that would trigger a measurement if the car was in desired gear and at right rpm. With that a single test engineer could safely perform the measurement while driving the car.
In conclusion torsional vibrations could potentially harm the drivetrain or at least worsen the comfort and driving experience of the car. They can be measured and mitigated to improve the overall quality and comfort of not only cars but all engine powered vehicles.
Dewesoft hardware and software is a good example of an adoptable system that can be used for a number of different measurements in perfect synchronisation.
ORDER TRACKING OF GAS TURBINES
Under the European research project ESPOSA (Efficient Systems and Propulsion for Small Aircraft (https://cordis.europa.eu/project/rcn/100644_en.html), for which COMOTI is a partner, the aim was to develop and integrate a novel design and manufacture technologies for a range of small gas turbine engines up to approximatively 1000 kW to provide aircraft manufacturers with better choice of modern propulsion units. It was also made researches for engine related systems which contribute to the overall propulsion unit efficiency, safety and pilot workload reduction, in this case the gear-box. As a producer a turbine motors, COMOTI came into this project with projecting, simulations and measurements for the transmission gear-box with a multiplication factor of 26. COMOTI has to project, simulate and test for this assembly. Among the tests made for the fault detection, an Order Tracking analysis was performed.
Founded in 1985, under the name of Scientific Research and Technological Engineering for Aviation Engines within INCREST, former aviation institute, COMOTI becomes in 1996, as a result of institutional evaluation and certification, COMOTI Turbine Engines Research and Development Institute. COMOTI Turbine Engines Research and Development Institute is the only unit in Romania specialized in development and integration of scientific research, constructive and technological design, manufacturing, experimentation, testing, technological transfer and innovation in the field of aviation turbine engines, gas turbine industrial machines and high speed blade machines.
For testing procedures, it was build a special stand (Fig. 2) on which the gears were brought to running speed. With 8 accelerometers placed axial and transversal to the axis of transmission, the signal was transform from time domain to the angular domain. The technique of Order Tracking was applied for bringing the asynchronously signals to a single sampled signal of the reference shaft, this resampling being actually an interpolation. The FFT of angular domain signal is defined as an order and represent a fraction of the angular velocity of the reference shaft. These orders make it possible to identify the frequencies which are related with angular speed and those which are different and which are a result of the structural vibration of the transmission gear-box.
For an order tracking analysis it was used 8 analog channels for acceleration measurement and a laser counter for measuring RPM. One channel is defined as alternatively RPM determination from FFT acceleration spectrum.
As an encoder for measuring the velocity it was used a non-contact laser system with black-white marks on the shaft. For finding the eigen-frequencies related with angular speed, the Campbell diagram was plotted as a vibration response spectrum as a function of the shaft rotation speed.Data acquisition system
- 8 Bruel&Kjaer Single axis accelerometers
For setting up the channels, it was specified 8 channels for accelerometers and one channel for acquisition the angular speed or rotation per minute. Alternatively, the RPM was acquired from the FFT spectrum of one accelerometer.
The regimes of gear-box running on different angular speeds was found during the order tracking analysis with Dewesoft. Using Dewesoft OT module, the time domain data was resampled in order tracking way. It was plotted FFT spectrum and Campbell diagram. The angular speed was taken alternatively directly from the acceleration spectrum and from laser encoder and was obtained similar results.
It was searched through this analysis to define the possible errors or faults in the ensemble of the gear box which might come from unbalancing, bearing faults, gearing imprecisions, eccentricity or assembling faults. Unbalancing was searched on the first order, eccentricity on the second order and different upper orders for bearings faults.
This application note shows how DEWESoft solutions can be safely and easily used with servo motors, stepper motors, etc. in conjunction with actuators, torque fixtures or other automation devices for control-type projects. The combination of DEWESoft X3 software along with an analog output device allows the user to easily control the forcing function of the test fixture while simultaneously measuring signals and inputs from the instrumented part. This configuration makes tasks such as File Playback possible where the user collects field data then brings the part back to a laboratory environment where the field data can be replayed and simulated for many cycles.
In the early days of Programmable Logic Controllers (PLC’s), the technology was revolutionary, simplifying millions of projects, replacing hundreds of relays and timers per project, speeding up various processes and making once time-consuming tasks a breeze. Many universities, regardless of the program thrived on teaching students the basics to circuits along with the industries advancements in PLC’s. In recent years, modern universities have taken a much more focused approach and degrees and are much more specialized in their own areas of interest with only a few degrees reaching detailed discussions and education in the topic of PLC’s.
Younger test engineers and technicians have a great deal of knowledge in many aspects of test and measurement including 3D modeling, material properties, advanced calculations, etc.; however, they lack the experience in traditional test setups such as the use of PLC’s. The industry is moving to stand alone solutions with easy and intuitive Graphical User Interfaces (GUI’s).
With the increases in demand for productivity in the test and measurement industry, more test engineers and technicians are looking to set up control projects but would rather not go back to learning the basics and yet another software to control a traditional PLC. This application note goes through a simple way to use DEWESoft’s X3 software which many test engineers and technicians are already familiar with and apply that knowledge to perform control projects in a safe and timely manner.
The first step to any project is designing and building a test fixture in which to perform the test. For this example, we have designed and built a small load frame out of anodized extruded aluminum to house a linear actuator and servo motor. In this example we used a Tolomatic ERD20/BNM05/SM154.2/LMI actuator along with a Tolomatic ACSI34-1Q1-B servo motor to apply our forcing function and a Futek LCM325 load cell to measure load in our part which could also be used at the feedback for PID Control.
Analog Output Device
Any SIRIUS unit with Analog Output (AO) and the function generator software upgrade can be to send the control signal to the servo motor. In this case we used a SIRIUSi-3xHV-1xACC+-2xACC-1xMULTI-1xSTG unit. In this test, we used the AO from the Multi-channel and used the STG-channel for the Load Cell.
The DS-WDT Watchdog could also be used at a safety precaution. With the SIRIUS Analog Output, the user can look for a heartbeat from DEWESoft throughout the test. If the heartbeat is missing, the DS-WDT Watchdog can be programmed to send a digital message to the motor stopping or coasting to stop motion.
Analog Inputs Setup
The analog input channels need to be configured based on the sensors used for the test. The Simple Measurement
Using DEWESoft Pro training is a great resource to setting up your analog inputs.
The function generator is an additional software package in which the user can define the analog output signal. Using your analog channel as “Signal Output” and creating either a Sine, Triangle, or Arbitrary waveform will be the most practical. The following image shows a user defined arbitrary waveform to program the actuator to perform a specific task. In the arbitrary waveform setting, old data could also be copied to simulate data that has already been collected.
In addition to configuring the waveform, the frequency, number of cycles, and output initiation should also be set. In this case we have set our frequency in a manner where the waveform will repeat itself every 10 seconds (frequency of 0.1Hz) and will be performed for 50 cycles. We have also programmed this analog output to have a manual start once we are in measurement mode.
If the DS-WDT Watchdog is to be used, it will also need to be programmed and can be done so following the user’s
manual at the link below.
Third Party Setup
During the first test for a new setup, a few parameters must be programmed into the automation system so that the system knows what to do upon startup and how to interpret the analog output from the SIRIUS System as well as the digital output from the DS-WDT Watchdog if the DS-WDT Watchdog is used.
“Home Position” must be selected. In this example I programmed my motor to retract to actuator until its hard-stop (at 10% load) then extend 0.5 inches.
Analog Input must be defined. First, we select that we want to operate in Analog Position mode then select that we want voltage to define position for a stroke-controlled application.
Digital Input must be defined. Finally, we select that we want one of the digital channels to “stop motion”. This selection must match how the user has wired in the digital signal as there are 4 conductors to digital inputs in this case.
Once your hardware and software has been programmed, you can go to measurement mode to begin running your automated test. If the function generator was configured to start “manually”, the user will have to go to the control tab and select “Start Output”. From this point forward, the test will be conducted just as the user has programmed. Once the test in initialized, the user can watch the test perform while data is being collected from the same measurement PC.
Previously users have had to use multiple systems to perform the forcing function and the Data Acquisition or have had to make the choice between the stability of a PLC with limited options in terms of Data Acquisition and post processing; or flexibility in terms of DAQ and post processing with the susceptibility from the control aspect. By using a combination of DEWESoft’s hardware and software in conjunction with Tolomatic’s easy to use programmable motors, the user can get the stability of a PLC but also the flexibility and GUI offered by DEWESoft’s powerful hardware/software combination.
DEWESOFT STRONGER THAN EVER
The success of our customers is a success for us
"It is hard to believe that yet another year is coming to an end... and what a year it was. New customers, projects, technologies, products, partners, co-workers and countries has transformed Dewesoft. We are now present with our own subsidiaries in 15 countries around the world.
The next steps in technology are so exciting - not just for us, but also for our customers who acknowledged our work with awarding us with orders in more and most demanding projects.
With our new technologies we are erasing the line between high end data acquisition and control systems which opens totally new world. Together with you, our valuable customers and partners, we will love to explore and expand in the years to come.
Wish you lots of happy moments in the coming year."
dr. Jure Knez, president
By far the greatest change in projects, customers and technologies is the merge of data acquisition and control world. Our data acquisition systems providing real time data to control software are applied in tasks ranging from simplification of durability test beds to the most demanding testing and control of rocket engines for space travels.
REAL TIME DATA ACQUISITION
Together with our customer Clemessy we have created a standard product "SyDew" (Syclone + Dewesoft). In 2018 we have already delivered around 1200 STG channels and the future looks prosperous - the plan for 2019 is to deliver additional 2000 channels.
We heavily expanded our KRYPTON product line, especially with the KRYPTON ONE line. With these products the customers are able to distribute their measurements down to a single channel.
We have started to build partner networks in solutions, products and sensors to make sure that the customers get total service and that our measurement devices are working perfectly with other devices.
In April we had the honour to host 400 partners and customers from all over the globe at the measurement conference in Slovenia.The aim of the conference was to share as much knowledge as possible and balance the educational part with a great portion of fun and networking.
Under the theme ”Where the love for technology and years of experience come together” our valuable customers shared their success stories - the event was a huge success. The red line of the conference was dewesoft software and instruments, but for the first time we also had a small trade show with exciting products from our partners such as sensor companies etc.
Sales and support network
Besides a major expansion in headquarters and of our sales offices in Germany, US, China, France and UK, we recently opened our offices in Sweden, Italy, Belgium, India and Denmark, aiming to fulfill the promise to offer our customers worldwide support. Dewesoft has now 15 subsidiaries in all major countries around the world.
Another great step in China was the establishment of a joint laboratory with Harbin Institute of Technology. The laboratory used for education as well as for research projects is named Dewesoft - and is fully equipped with our systems.
Mounting plate for a Krypton system features an aluminum ground plate with an easy click mechanism, which is the same as the one on top of Krypton instruments. It is suitable for mounting any Krypton as well as a Krypton CPU. Please note that the mechanism is not meant to sustain large vibrations and a huge stack of devices.
Featured eventsAll the upcoming events can be found on the Dewesoft website
- 07.01.2019: Sci Tech 2019
- 16.01.2019: Siat Expo
- 29.01.2019: SEPEM Industries
- 29.01.2019: IMAC Orlando Florida
- 19.02.2019: SAE Hybrid & Electric Vehicle
- 06.03.2019: Testing Expo
- 19.03.2019: APEC Anaheim
- 25.03.2019: Forum Mesure 2019
Upcoming webinarsAll the upcoming webinars can be found on the Trainings website
- 15.01.2019 08:00 CET: X3 SP5 new features
- 15.01.2019 09:00 CET: Order tracking
- 15.01.2019 16:00 CET: X3 SP5 new features
- 15.01.2019 17:00 CET: Order tracking
- 22.01.2019 08:00 CET: NEW Combustion analyser webinar
- 22.01.2019 09:00 CET: C++ Script
- 22.01.2019 16:00 CET: NEW Combustion analyser webinar
- 22.01.2019 17:00 CET: C++ Script