With the ASC RAIL series of MEMS-based precision accelerometers and gyroscopes certified to EN 50155 and other relevant industry norms, ASC Sensors empowers railway networks across the globe. These robust analogue, digital and smart sensors set new milestones in railway safety, capacity and productivity.
INFRASTRUCTURE MONITORING WITHOUT SERVICE DISRUPTION
Inertial sensors play a critical role in accurately measuring vibrations – impacting vehicles as well as rail infrastructure. Beyond their distinct value in the testing and certification of new train models, ASC’s RAIL accelerometers and gyroscopes are ideally suited for permanent installation on regular and high-speed trains. They are integrated into customised measurement systems to enable continuous track monitoring from active in-service trains without service disruption. Based on their accurate real-time collection of data, deviations in longitudinal height, dynamic direction or distortion of tracks are calculated.
Applications include:
- Characterisation of track geometry (EN 13848)
- Specifying structural requirements for bogie frames (EN 13749)
- Dynamic interaction pantograph/overhead contact line (EN 50317)
As across the world, a substantial share of network delays and disruptions are caused by track alignment errors and related issues. These require low-speed zones and service discontinuations that further compound delays and inefficiencies. Based on ASC RAIL sensors that are dedicated and certified to rail applications, tracks and further infrastructure assets can be monitored from rolling stock in real time. Therefore, they can be maintained predictively and issues addressed proactively, before service disruptions or more serious consequences occur.
EVALUATION OF SAFETY-CRITICAL DRIVING DYNAMICS ON THE BOGIE
Rolling stock, too, is constantly being monitored to ensure safe, efficient operation and cost-effectiveness. Particularly on high-speed trains, inertial sensor technology helps achieve appropriate driving dynamics, running stability and to avoid derailment.
This is because at higher speeds, rail vehicles tend to exhibit a natural sinusoidal motion of the wheel sets due to the conical wheel profiles. This motion around the z-axis is sinusoidal at small amplitudes with a constant wavelength; its frequency, therefore, increases with travel speed. Once the critical running speed gets exceeded or if the undercarriage is insufficiently damped, that sinusoidal motion can become instable and transition into safety-critical swaying. Vibrations can build up, leading to severe lateral vehicle movements and increased flange forces. This can result in so-called hunting oscillation, potentially leading to a zigzag motion with the wheel flanges forcefully striking the rails.
Extremely robust inertial ASC sensors installed at the axle box, bogie frame and various points across the vehicle body accurately determine all relevant acceleration forces. They feature an excellent signal-to-noise ratio and a precise frequency response below 10Hz – essential requirements for the demanding measurement of low frequencies and lateral accelerations of a few tenths’ m/s2. Applications include:
- Running characteristics of railway vehicles (EN 14363)
- Passenger ride comfort (EN 12299)
THE ASC RAIL SERIES
Meeting diverse relevant railway norms, the ASC RAIL series’ performance significantly facilitates implementation. Vehicle manufacturers, infrastructure and railway operators, system integrators as well as engineering and testing service providers rely on a proven set of precise, stable sensors ready for installation that drastically reduces individual documentation requirements.
ASC RAIL sensors have been designed to resist the toughest challenges – for optimal performance and long-term use in harsh conditions. With this flexible, dedicated sensor portfolio, rail operators can realise custom solutions. The outcome:
- enhanced safety
- stable long-term performance
- increased profitability of rolling stock
Superior sensor technology made in Germany, solving complex measuring challenges globally to ensure high precision, customer focus, flexibility and rapid delivery. Visit ASC Sensors at Innotrans Hall 27, 690.
Words by Oliver Stohlmann on behalf of ASC Sensors: www.asc-sensors.de
