Skip to main content

Resilience of Bolometer Sensors

Vibration testing of mechanical resilience of bolometer sensors and sensor holders under ITER-relevant conditions


The ITER bolometer diagnostic will provide the measurement of the total radiation emitted from the plasma, a part of the overall energy balance. Up to 550 sensor channels will be installed in ITER in 71 cameras of various sizes and types. The sensor holder is the component inside those cameras to provide attachment and signal connections to the sensor itself. A design of a sensor holder has been proposed previously based on ceramic front and back plates with wire bonded contacts to the sensor and welded signal cables.

This concept can provide the reliable electrical connections required for ITER at temperatures up to 350 C and had been prototyped and proven to be manufacturable. In order to verify its resilience against mechanical loads as well as that of the sensors, sensor holder assemblies have been subjected to accelerations on a shaking table. The magnitude of the accelerations applied in the frequency range from 5 Hz up to 1 kHz) have been deduced based on load definitions from ITER describing the floor response spectra for typical seismic events as well as the ones expected during disruptions due to electro-magnetically induced forces in bolometer cameras and port structures within which they are mounted.

A particular focus has been placed on testing whether it is beneficial to cover the bond wires with a ceramic paste to protect them against fatigue breaks due to vibrations. The tests demonstrated that the chosen sensor assembly is well capable of withstanding all applied loads without failures and thus demonstrating its structural integrity during the expected operations. Within the limited number of load cycles no need to apply the ceramic paste could be identified.

The ITER bolometer diagnostic shall provide the measurement of the total radiation emitted from the plasma, a part of the overall energy balance. Up to 550 sensor channels will be installed in ITER in up to 71 cameras of various sizes and types. The sensor holder is the component inside all those cameras that provides attachment and signal connections to the sensor itself. It might vary in shape within each camera, but concepts for implementing signal connections and handling of loads in all cameras are very similar, if not identical.

Another important result is that the bolted connections in the sensor holder were neither affected by the acceleration tests nor by the baking afterwards. Despite that bolts were tightened only by hand with a torque of only 0.1 Nm and without specific precautions against loosening under vibrations, all bolts were still tight after each test. Furthermore, no damage was noticed on the sensor holder components after acceleration testing. This demonstrates that the proposed sensor holders can withstand typical mechanical loads as expected for ITER and that they will not lose their structural integrity.
Nonetheless, the assembly process is very demanding and shows significant risks. For final manufacture it is strongly recommended to optimize and practice the assembly procedure thoroughly, involving the provision of a sufficient number of spare sensors and components.

IoT sensors, smart sensors, wireless sensors, optical sensors, biomedical sensors, pressure sensors, temperature sensors, proximity sensors, humidity sensors, chemical sensors, biosensors, motion sensors, infrared sensors, environmental sensors, wearable sensors, industrial sensors, acoustic sensors, microelectromechanical sensors, nanotechnology sensors

#SensorTechnology, #SmartSensors, #IoTSensors, #BiomedicalSensors, #WirelessSensors, #PressureSensors, #TemperatureSensors, #OpticalSensors, #ProximitySensors, #ChemicalSensors, #Biosensors, #InfraredSensors, #HumiditySensors, #EnvironmentalSensors, #MotionSensors, #WearableSensors, #IndustrialSensors, #AcousticSensors, #NanoSensors, #MEMSSensors

Comments

Post a Comment

Popular posts from this blog

Global Lighthouse Network

Smart, sustainable manufacturing: 3 lessons from the Global Lighthouse Network Launched in 2018, when more than 70% of factories struggled to scale digital transformation beyond isolated pilots, the Global Lighthouse Network set out to identify the world’s most advanced production sites and create a shared learning journey to up-level the global manufacturing community. In the past seven years, the network has grown from 16 to 201 industrial sites in more than 30 countries and 35 sectors, including the latest cohort of 13 new sites. This growing community of organizations is setting new standards for operational excellence, leveraging advanced technologies to drive growth, productivity, resilience and environmental sustainability. But what exactly is a Global Lighthouse and what has the network achieved? What is the Global Lighthouse Network? The Global Lighthouse Network is a community of operational facilities and value chains that harness digital technologies at scale to ac...
Post a Comment
Read more
 How Network Polarization Shapes Our Politics! Network polarization amplifies political divisions by clustering like-minded individuals into echo chambers, where opposing views are rarely encountered. This reinforces biases, reduces dialogue, and deepens ideological rifts. Social media algorithms further intensify this divide, shaping public opinion and influencing political behavior in increasingly polarized and fragmented societies. Network polarization refers to the phenomenon where social networks—both offline and online—become ideologically homogenous, clustering individuals with similar political beliefs together. This segregation leads to the formation of echo chambers , where people are primarily exposed to information that reinforces their existing views and are shielded from opposing perspectives. In political contexts, such polarization has profound consequences: Reinforcement of Biases : When individuals only interact with like-minded peers, their existing beliefs bec...
Post a Comment
Read more

Quantum Network Nodes

An operating system for executing applications on quantum network nodes The goal of future quantum networks is to enable new internet applications that are impossible to achieve using only classical communication . Up to now, demonstrations of quantum network applications  and functionalities   on quantum processors have been performed in ad hoc software that was specific to the experimental setup, programmed to perform one single task (the application experiment) directly into low-level control devices using expertise in experimental physics.  Here we report on the design and implementation of an architecture capable of executing quantum network applications on quantum processors in platform-independent high-level software. We demonstrate the capability of the architecture to execute applications in high-level software by implementing it as a quantum network operating system-QNodeOS-and executing test programs, including a delegated computation from a client to a server ...
Post a Comment
Read more