基于管式应变天平的飞艇螺旋桨飞行测力系统

Flight Measurement System for Airship Propeller Based on Tube-type Strain Gauge Balance

平流层飞艇巡航高度距地面25 km左右,由于空气温度和密度的不同,螺旋桨提供的推力与地面试验可能存在较大的差异。为飞艇螺旋桨设计了测力系统,实时测量飞行中螺旋桨受到的力和力矩,用于飞艇的气动参数辨识。测力系统主要包括管式二分量应变天平和数据采集系统。天平尺寸根据飞艇的螺旋桨结构设计,尽量降低了其对飞艇本身的干扰,并采用序列二次规划方法对天平进行优化,提升轴向力信号输出。数据采集系统用于传递天平采集的载荷,同时内含多种传感器以修正天平信号。对测力系统进行了包含温度、气压、轴向加速度、倾角、振动等影响因素下的校准和地面模拟试验,保证了系统测量的准确性和可靠性。飞艇螺旋桨测力系统的飞行试验数据结果表明,其准确度、一致性和可靠性好,可以满足测量需要。

The cruising height of the stratospheric airship is 25 km from the ground.Due to the differences in air temperature and density,the propulsive force provided by the propeller is likely to be quite different from the ground experiment.A flight measurement system is designed for the airship propeller to measure the force and moment in real time,which are received by the propeller during flight.It is used to identify the aerodynamic parameters of the airship.A tube-type two-component strain gauge balance and a data acquisition system are included in the measurement system.The dimension of the balance is designed considering propeller’s structure,which can minimize the interference with the airship.And sequence quadratic programming(SQP)method is used to optimize the balance to enhance the axial force signal output.The data acquisition system is used to transmit the load collected by the balance,and contains a variety of sensors to correct the signal.The calibration and the ground simulation test which include influencing factors such as temperature,air pressure,axial acceleration and vibration,are carried out to ensure the accuracy and reliability of the measurement system.The results of flight test data show that the accuracy,consistency and reliability of the system test are good,which can meet the needs of measurement.