When it comes to public transportation lots of tests and measurements are required to ensure safety and passenger comfort. The trains for example require many measurements during development phase, first measurements when they come in operation and repetitive measurements for determining the quality of the tracks. High number of channels distributed over the long vehicles can be easily achieved with the use of DEWESoft NET - networked data acquisition solution.

From New York subway to crash testing of high speed trains in Europe we provide solutions in this area. Here are only some basic applications.

Inspection and performance testing

To determine the highest speed of the trains the measurement of acceleration of the trains and under carriage must be performed to calculate the derailment index. Not only that we are able to calculate all the values with extensive math library which DEWESoft offers, but we can also acquire GPS data to determine where the section with potential problems is and video data to SEE the train as it drives along the track.

Application reports

Rail car testing	Rail Car Testing at the New York Metros New York Subway, USA	View
Application Each train must be tested as they come from the factory. The same tests as with development vehicle (acceleration, deceleration, voltage tests) must be performed. Due to limited time that the trains can be tested system must be simple to use providing test results immediately after the end of testing. Measurement challenge The measurement consists of voltage and current channels, speed input with optical sensors as well as GPS for applications above ground. The ability of DEWESoft to use templates in Flexpro post processing package offers a very nice chance to offer ready-made reports which can be finished immediately after testing. Train testing DEWESoft in action DEWESoft in action Data export to FlexPro for posr processing
Data recording	Trains and railroad infrastructure monitoring London Underground, United Kingdom	View
Application For maintenance purposes the track, train and tunnels of the underground needs to be tested repeatedly. In addition to that, the system must be capable of measurement the track performance, vibration on surface building as well as train ride comfort. Measurement challenge A challenge in this application is clearly the need to have a very flexible, but nevertheless portable system to be able to fulfill all the needs. The system must measure acceleration, voltage, frequency and must be upgradable and expandable. The Dewetron 2010 with Dewesoft is preferred choice since it offers all that functions.
Increasing allowed track speed	Increasing allowed high speed on rail tracks Slovenske Železnice, Slovenia	View
Application Since Slovenia bought high speed trains, there is a long term effort to increase maximum allowed speeds on certain segment to reduce the travelling time. A special filter and math formulas must be calculated to determine derailment index - the number which tells if the train is still safe on tracks. Measurement challenge The need of the system is to measure static and dynamic acceleration on the undercarriage and in the cabin. The system is also equipped with the video camera and the GPS for determine the position of the train. Filters and formula inside Dewesoft are used to calculate all parameters even during measurement. Pendolino train used for test DEWESoft in action DEWESoft in action Sensor placement Camera setup Connections setup

Passenger comfort

Passenger comfort is one of the numerous tests performed on the public transportation. With the measurement of vibration, the ride comfort index is calculated to determine how good the vehicle and the track perform. The systems are used not only for a single decision pass/fail criteria, but also for determining the cause of the higher values and providing the ways to analyze the possible solutions.

Ride testing

Dewesoft is not only fun to work with, but it plays a major role in fun applications. The software with the support of gyro platforms from XSens and Genesys in combination with video data offers great base for analyzing amusement park ride tests. The new rides must be checked for safety as well as the passenger comfort that people don't get sick while riding it.

Component testing

Since transportation is very similar to automotive, virtually the same rules apply to testing components in transportation application area.

Application reports

Transmission testing	Transmission system testing Alstom Rail Transport, Italy	View
Application The transmission shaft of the train is covered with the housing which prevents that the transmission shaft falls under the train in case it brakes. With over 300 km/h that shaft would most probably cause derailment of the train which needs to be prevented. The test must prove that the housing will hold the shaft if it fails. Measurement challenge The system acquired several analog signals from the test bench with the addition of two high speed video cameras. The cut was initiated on the shaft that it will break. After applying the load the crack propagated until the shaft was broken. During that time all the data was recorded on huge hard drive. Two video cameras clearly showed the behavior of housing when the shaft broke off. This train components are tested Train transmission Train transmission DEWESoft in action Test result - shaft safety container Transmission testing

Structural testing

When designing the vehicle, all mechanical parts are done with the use of computer and qualified with finite element method to determine natural frequencies of the structures. However, the need to check those method is needed more than ever to produce a closed loop to correct the models that they fit the measurement results. DEWESoft provides DeweFRF add-on software to add the ability to import the geometry models, measure transfer functions with the use of either hammer or shaker excitation and see fascinating animation of the structures on the fly. Data can be easily exported to UFF format for further processing.

Order tracking

When determining how the structures behave under real operating conditions, order tracking provides the means of seeing the structural response to real life excitation. The rotating parts of the vehicle like engine, shafts or the wheels creates excitation forces on the structure. Did you ever had a car starting to rattle and shake at certain vehicle speed? This car was for sure not tested with DEWESoft and those high vibrations were result resonance frequencies of some elements at certain input frequencies.

By measuring rotating speed and the response (in terms of vibration, noise and others) the Nyquist, Bode and three dimensional FFTs are generated on the fly giving clear picture of the frequencies having a problem.

Torsional vibration

If the acceleration sensors provides information about linear movement, torsional vibration procedure provides the information about angular vibration. Imagine a long shaft going through the vehicle. Like each structure has linear natural frequencies, this shaft will have angular natural frequencies resulting at high angular vibration at certain rotation speed. To check the bending of the shaft, we mount any kind of angular sensor on each end of the shaft and measure the angle difference. The data can be used in order tracking to give a clear indication of natural frequencies.

Combustion analysis

Dewesoft adds the power of acquiring angle based data and calculate parameters of combustion analysis (maximum pressure, MEP, heat release, temperature, knocking, combustion noise and others). The p-v and CA-scope display shows the measurement results while measuring. DEWESoft uses multi-threading technology to use the new multi-core processors for real time calculations.

Another major advantage of CA module is that it can be used with other data sources like CAN bus, video, OBDII and time domain analog signals, all synchronized with engine data.

Electrical systems testing on vehicles

One of the important parts of testing on electrical vehicles is power analysis. With the support of 50, 60, 400, 800 Hz and also 16 2/3 Hz and variable frequency as input to the power module, DEWESoft offers a great base for testing electrical systems.

Distributed acquisition

Distributed data acquisition on long vehicles is crucial in system design. Since DEWESoft offers a great chance to synchronize more systems together, customers can buy more small data acquisition devices and use them independently, but when higher number of channels is needed, they can be connected together with LAN and sync connection to act like a single instrument.

Crash tests

Public transportation vehicles must be also checked for crashes. The trains for example are driven to the solid barrier. DEWESoft with the support of high speed data acquisition cards as well as high speed cameras is perfect software to perform such tests.