Fraunhofer Adaptronics Alliance

Mode RC-Car-Demonstrator - Wireless Sensor Network for Damper Monitoring

Image 1: RC-Car-Demonstrator

To show a new ability of monitoring vehicles dampers, an RC-Car is equipped with four wireless sensor nodes. Those nodes acquire vibrations related to the health state of the damper and transmit them to a central observation unit.

The sensor nodes make use of sensing units which in the reported case are MEMS type accelerometers in tailored housings. The signals coming from the sensors are amplified, digitized and processed in a programmable embedded unit. This unit is connected to a Bluetooth interface that establishes the communication to a central unit.

In the presented case, the central unit of this network of smart sensors is a tablet PC. Using this computer, different results coming from the sensor nodes can be postprocessed. Firstly, it is possible to view the acceleration signal measured from each sensor node. Secondly, a rainflow matrix can be displayed counting the different vibrational amplitudes that have happened during operation. This matrix is generated inside the sensor nodes and its acquisition can be controlled via the tablet PC.

Image 2: MEMS-type accelerometer (without housing) and sensor node
Image 3: Components of sensor node: MEMS-type accelerometer, sensor node consisting of embedded hardware and Bluetooth interface, MEMS-type accelerometer without housing

Using the described technology - sensor nodes, wireless communication, central unit - a system can be designed that autonomously acquires the parameters indicating the health state of a damper and transmits them to a further decision making unit.