Construction machines are becoming more efficient reducing their environmental footprint. STW from Kaufbeuren, Germany, offers a sensor portfolio suitable for everything from highly automated mobile machines through to mobile robotics. With special technologies, for example for hydrogen powered machines, the sensing experts from the Allgäu are helping paving the way to zero emissions.
bauma 2022 in Munich is all about the current and future construction machinery trends: Automation, sustainability, digitalization, and reduced emissions, down to zero emissions. STW has been developing robust and innovative sensor technology for mobile machinery for almost 40 years. With the current sensor portfolio, the tradition rich company is now at the forefront of technology trends. From October 24th to 30th, 2022, STW will present new developments in pressure, temperature, inclination and strain sensors. All STW sensors are designed for harsh environmental conditions. With a protection class of up to IPX9K and road approval, the sensors are optimal for the requirements of mobile machinery. For fast and reliable integration, STW products are supported by the openSYDE software engineering platform, making system integration, programming and monitoring efficient and intuitive.
Safe under pressure
STW offers the M01 series of pressure sensors for both low and high pressure applications. Using the M01 modular concept, customer-specific variants for hydrogen or CNG/LPG can be realized, for example for mobile fuel cells and the corresponding infrastructure, and so, these products make an important contribution to emission reduction. Depending on the configuration, the M01 products can be used with media temperatures ranging from -40°C to +150°C.
For safety related applications, STW offers the F02 Safety pressure sensor for pressure ranges up to 1200 bar. This sensor series is certified up to SIL 2 / PL d. The overall accuracy is 1 % FS or better in the compensated range of 0...+80 °C. Both product lines, M01 and F02 Safety, are available with a wide range of process and electrical connections for flexible system integration.
Stable measurement in the presence of disturbances
The disturbances that occur in mobile machines during rugged operation, including shock and vibration, typically influence measurement results, especially in inclination sensors. To address this, STW has equipped the SMX.igs-e inclination sensor with an Inertial Measurement Unit and Kalman filter functionality. This merges the acceleration and rotation rate data using sensor data fusion technology. Based on the results of the sensor fusion, the required measured values are calculated, and their future course estimated and corrected. The resulting measurement is more stable and precise, even in the presence of strong interference. The Kalman filter applied is characterized by its high dynamic range and good damping of parasitic accelerations. Integrated sensor data fusion reduces the load on the mobile machine control system and reduces data streams on the machine, leaving more bandwidth for complex automation processes.
STW's SMX.dms-a strain sensors are used to monitor the loads on a machine and its components. For example, they can be used to measure the deflection in steel booms. This enables the indirect measurement of the acting forces and vibrations. The SMX.dms-a strain sensors are characterized above all by their low profile and simple integration during the mobile machine assembly process.
Robust in any media
The greatest challenge for temperature sensors in mobile machinery is the rapid detection of temperature changes, for example in pneumatic and hydrostatic drive systems, which are best detected directly in the operating media. In the T01, parts in contact with media are made of stainless steel and so, in combination with welded temperature elements, the T01 has outstanding media compatibility and response times. The accuracy is 0.6 %FS in the temperature range from -40 °C to +150 °C and 0.4 %FS from -40 °C to +85 °C. With excellent EMC characteristics, and high shock and vibration resistance, the T01 is ideally suited to demanding applications like mobile hydraulics.
Equipped for tomorrow's trends
With their range of sensor products and their latest control systems, STW are prepared
for the automation and digitalization requirements of current and future mobile machines. The open-source software platform openSYDE makes integration of the components especially user-friendly. Innovative and intuitive: This is how the sensors from Kaufbeuren will be presented at the world's leading construction machinery trade fair in Munich.