AST’s fluid/gas sensors often combine several measurement principles into one sensor. For example, fill level measurement is often combined with a measurement of the concentration/quality of the liquid. In the case of fill level measurement, the technologies used range from ultrasound to capacitive systems that take readings from the outside through the tank wall to hydrostatic pressure measurement. The most suitable measuring principle is selected on the basis of customer requirements and the respective available installation space.
For concentration/quality measurement, thermal conductivity is often measured in addition to using ultrasonic systems. Sensors based on the tuning fork principle not only offer high-precision density measurement, but also allow the viscosity of the medium to be measured. The measurement of resistive and capacitive properties of liquids rounds out the technology portfolio. Concentration measurement is used, for example, in SCR (measurement of urea concentration) and in determining the antifreeze properties of the washer fluid in the washer fluid tank (measurement of ethanol concentration). All AST sensors are equipped with a microcontroller and are therefore able to execute complex algorithms directly on the sensor. An output signal processed in this way is then made available in analog or digital form. Examples of fluid/gas sensor applications include leak detection in hydrogen-powered vehicles and measuring the concentration of antifreeze in windshield washer fluid
Sensors for the detection of leakage (volume percentage of hydrogen in air) in the H2-supply of FCE-Vehicles
Vehicles with hydrogen drives require a safety concept at the highest level. In particular, the detection of a leak in the hydrogen supply is an essential element in the careful handling of the critical medium hydrogen. The Hydrogen sensor based on the TCS process with its robust measuring principle fulfills this requirement perfectly. It is characterized by its low cross-sensitivity to other gases and its long-term stability.
Clear Vision Sensors
Sensors for measuring cleaning fluids: fluid level, temperature, and antifreeze
Manual and autonomous driving alike are only possible if both the driver and the visual assistance systems have a clear view.
Especially in the case of poor weather conditions, this can only be ensured if there is sufficient fluid in the corresponding cleaning system and if the fluid does not freeze during the journey.
The AST sensors measure the fluid level and the temperature in the fluid tank as well as the antifreeze (ethanol/methanol) concentration. This enables the driver to top up in good time and travel with confidence.
Sensors for measuring the fluid level and urea concentration of diesel exhaust fluid
In diesel vehicles, exhaust gas treatment with AdBlue® reduces nitrogen oxide (NOx) emissions by up to 90 percent. However, engines equipped with this technology only run if the tank contains sufficient AdBlue® fluid of the required quality.
AST sensors monitor the fluid level in the AdBlue® tank so that the driver can top up the fluid in good time. The sensors also measure the quality of the AdBlue® fluid, which features a mixture of urea (32.5%) and demineralized water.
This ensures compliance with the statutory requirements and prevents any potential improper use.
Water Injection Sensors
Sensors for measuring the fluid level and the degree of purity for water injection systems
Water injection is a temperature reduction process for internal combustion engines, boosting performance while also reducing fuel consumption and emissions.
In order to prevent damage to the engine, it must be ensured at all times that sufficient demineralized water and no foreign fluids such as gasoline or windshield wiper fluid are present in the water tank.
The AST sensors detect foreign fluids via a conductivity measurement (based on an additional measured variable), as distilled water is non-conductive. Other non-conductive fluids are also safely detected.
Battery Coolent Fluid Sensor
Sensor for property monitoring of Electrical Vehicle Battery Coolant Fluid (direct cooling topologies)
Property monitoring of the coolent fluid used for direct cooling of High Performance EV batteries is an essential task for the safe operation of the vehicle. Especially the isolation resistance of the fluid is a critical parameter but also the information about the degrading of other parameters will help to define the optimum time for maintenance. AST’s BCF-Sensor is able to determine the isolation resistance, the relative dielectric constant, the density and the viscosity of the fluid. This multi-dimensional approach gives an outstanding performance in terms of accuracy and reliability of the measurement.
Air quality sensor
Air quality sensors permanently measure the intensity, degree of pollution, and number of odor molecules in the exhaust air. These measurements can then be used to adjust the fan performance levels and generate a pleasantly fresh atmosphere.
In addition, the continuous measurement of air pollution enables our smart sensors to predict when the filters will need to be replaced and when the unit will next require servicing.