Wireless sensor network system for solar array vibration measurement in space station
Based on the requirement of flexible vibration measurement and dynamic parameter identification of the solar array in China space station,China has successfully applied a wireless accelerometer sensor network in orbit for the first time.Firstly,the architecture designs of the wireless sensor network in Tianhe core module and Wentian lab module are introduced.Then,for the requirement of multi-source data fusion of modal identification,the responsive TCP/IP time synchronization based on wireless delay self-optimization compensation and the broadcast UDP time synchronization based on wireless reference node are proposed.To address the issue of measurement interruption of wireless node communication links caused by the possible obstruction of the solar array,an autonomous wireless network topology dynamic management method based on relay transmission is proposed,achieving high reliability transmission of vibration measurement data.The in-orbit application of wireless accelerometer sensor networks in Tianhe module and Wentian module is summarized.The flight measurement data show that the time synchronization accuracy is better than 20ms for TCP/IP mode and 70ms for UDP mode.The highly reliable acquisition capability of wireless network is evaluated by using the measurement data of active excitation conditions at a 180° angle of the solar array,meeting the requirement for modal identification.Finally,based on the flight test results of space station solar array vibration measurement,several inspirations are proposed for the widespread application of future wireless sensor networks in orbit.