Construction

Digital twins of buildings are increasingly being created in the planning, implementation and operating phases. Building information modelling (BIM) allows the visualization of the entire life cycle of buildings. The big data volumes necessitate compact and intelligent sensor solutions. Smart sensors from ASC provide the answer to these challenges.

ASC inertial sensors monitor construction machines during operation for timely reporting of even minimal deviations from standards values. This allows predictive maintenance to prevent unplanned downtimes.

Capacitive accelerometers of the ASC OS series  monitor the functionality of hydraulic vibrators, for example, which are used for analysis and compacting of subsoil. The sensors detect the frequency and amplitude of vibrations created by the placement of steel wall sections. Deviations in the frequency response can be an indication of damage to the piling equipment.

Condition monitoring of construction vehicles requires not only precise sensor signals – the sensors must also be designed for high resistance to impacts and the forces exerted on the cable connections.

The harsh everyday conditions of construction sites place high requirements on special concrete mixing vehicles. Durability tests provide engineers with important data to prevent errors as early as the vehicle design stage.

This is where the capacitive accelerometers ASC 5511LN comes into play: LN (Low Noise) sensors from ASC feature an outstanding signal-to-noise ratio, an integrated cable and IP67 protection.
With these sensors it is possible for example to obtain ideal and precise measurements of the vehicle life cycle and stability of single modules. Stability is especially important in concrete mixers, because the weight involved directly affects the vehicle’s actual transport capacity.

Mobile mapping systems are used for the assessment and monitoring of infrastructure buildings and for creating and updating map material. Mobile mapping is based on the principle of sensor fusion, since the imaging sensors and laser scanners have to be positioned and oriented by means of inertial measuring systems to ensure precise 3D detection of the area.

In particular, the high data rates of inertial measurement units, in combination with GNSS, allow effective mobile mapping processes by land, rail or air. The analogue ASC IMU 7 or ASC IMU 8 and the digital IMUs HG4930 and HGuide i300 from Honeywell offer the ideal solution.

While the analog IMUs allow maximum freedom in the processing of data and a modular concept that enables application-specific configuration of the users’ IMUs, the digital versions feature numerous pre-configured settings that allow fast start-up using the Honeywell HGuide data reader software.

Safety-related components of buildings must be monitored continuously. This is especially the case with power plants or tunnels, with structures that are affected by tectonic processes. The detection of seismic waves for example allows immediate alerting of the authorities and fast implementation of safety actions for the population in an emergency. A fundamental requirement here is the use of seismic sensors that reliably detect even very small amplitudes of vibrations.

The capacitive accelerometers of the ASC EQ series fulfil the requirements of Motion Class B and can achieve a resolution of less than 1 µg.

Measurement while drilling is required to avoid collisions when several drilling processes are carried out at the same time. Due to the harsh conditions regarding vibrations and high impacts during the drilling process the measuring devices must be very robust. In addition, the shocks that occur must not affect the measurement signals.

Therefore, the sensors of the ASC QF-series are ideally suited for this application, as they provide a very high shock resistance of up to 1,500 g but also achieve a very low noise level with a resolution of less than 1 µg. As a result, the capacitive based accelerometers detect the smallest deviations from the predetermined drilling direction, which could be caused by obstacles in the ground.

The capacitive accelerometers of the ASC CS series were specially developed for monitoring vibrations in bridges. These sensors are used for example to monitor the longest sea crossing in the world (Hong Kong-Zhuhai Macau bridge).

The bridge, with a length of 55 km, spans a high-traffic waterway, where there is a major risk of collisions with ships. In case of an accident, it must be determined that the mechanical structure of the bridge is ensured. Comprehensive dynamic characterization of the bridge properties is made possible by the output signal of 4-20 mA, which guarantees loss-free transmission of the measurements over long distances.

Continuous condition monitoring of buildings by means of inertial sensors is also known as structural health monitoring (SHM). These measurements provide valuable information both for construction calculations and for regular safety inspections of critical building components. Maximum precision and reproducibility of measurements are the requirements of sensors in SHM systems – especially with a view toward long-term monitoring of seasonal or cyclical influences, and also the detection of overloads or material defects.

For structural health monitoring ASC offers capacitive accelerometers with a high signal-to-noise ratio and low measuring ranges. The hermetically sealed sensors of the ASC OS series are often used for example for reliable recording of vibrations in buildings in harsh climatic conditions.

Remote-controlled or autonomous drones (unmanned aerial vehicles, or UAVs) are used to analyze inaccessible structures such as dams or bridges. The goal is to prolong the operational life and to plan maintenance more effectively. UAVs create high-quality photographs that are used for the analysis and identification of structural damage.

The gyroscopes ASC 271 (uniaxial) and ASC 273 (triaxial) are used in dynamic yaw rate and roll rate measurements, as well as position and motion measurements. In difficult environmental conditions such as strong gusts they also guarantee optimal orientation and stabilization of unmanned aerial vehicles.