Design of a small form factor high-frequency wireless data acquisition and logging system.

摘要

The experimental tools necessary for full numerical model validation and understanding the detailed physics of any parachute system were not available until now. If successfully developed and applied, wireless sensor networks will provide experimental data that is critical in order to validate the structural dynamics and computational dynamic code. The goal of this thesis is to design, build, and evaluate a data acquisition and logging system to collect sensor data on a parachute.; Due to the specific application requirements, the system needs to be small, light-weight, and able to acquire and log sensor data at a high frequency. We present a system design based on the master-slave architecture using a commercial-off-the-shelf mica2dot(TM) wireless sensor network hardware platform and TinyOS(TM) operating system. The master node broadcasts commands to slave nodes via wireless channel to start data acquisition at specified sampling rates for a specified number of samples. This removes the need for wires and allows for easy time synchronization. Upon request from the master node, each mica2dot(TM) mote starts to convert sensor signals to digital data and stores the data in its flash memory, which are read out later after experiments have been completed.; The performance of the system, including wireless communications between master and slave nodes, Analog-to-Digital-Converter (ADC) conversion rate, and flash memory throughput, are measured experimentally. The results show that the system design is well suited for the application. While the system is specifically designed and implemented to work in a parachute, the design can be used or adapted to a wide range of embedded sensor data acquisition and logging applications.