【作者】 苑海静；

【导师】 赵琳；

【作者基本信息】 哈尔滨工程大学 ， 导航、制导与控制， 2010， 硕士

【摘要】 基于MEMS惯性器件的低成本航姿测量系统在军事领域和民用领域的都具有广泛的应用前景。本文依托实验室有关低成本船用卫星天线姿态测量系统的在研项目,开展基于MEMS惯性器件、磁强计及GPS的组合航姿系统相关算法研究,并通过仿真验证了算法的可行性及有效性,为MEMS航姿测量系统在船载卫星天线稳定系统中的实际应用奠定了一定的基础。(1)MEMS陀螺随机漂移是影响姿态解算精度的主要因素,针对其误差模型的未知性,本文利用时间序列分析法通过静态测试数据建立了陀螺随机漂移的ARMA模型,并将其应用于后续姿态估计算法比较中。(2)在不使用GPS的情况下,根据船舶运动特点与系统工作要求,通过对多种姿态更新算法的理论分析与仿真比较,得出修正的Rodrigues参数法计算量明显比四元数法和旋转矢量法要小,计算精度与四元数相近,同时克服了四元数描述姿态时存在冗余带来的不足,为姿态更新算法选择提供依据。(3)在前述研究的基础上,推导了以陀螺零偏和修正的Rodrigues参数为状态向量,以加速度计、磁强计输出为观测向量的EKF姿态估计模型,利用与其影子参数相互切换的方法解决了修正的Rodrigues参数在描述姿态时存在奇异的问题。通过全姿态以及摇摆运动条件下的仿真验证了算法的可行性及优越性。(4)为检验ARMA模型的适用性,通过静止及摇摆运动条件的仿真得出,采用ARMA模型对姿态角和陀螺零偏的估计及补偿精度在静态条件下较随机游走模型高,但在摇摆运动条件下精度和计算量均不理想,而基于后者的MRP EKF估计算法更具普适性。在调整观测噪声方差阵的前提下,为进一步减小重力和地磁向量在受到干扰时的系统输出误差,引入GPS信息,开展了MEMS AHRS/GPS组合系统松耦合Kalman滤波算法的研究,仿真实验证实了方案的有效性。更多还原

【Abstract】 Low-cost Attitude and Heading Reference Systems based on MEMS inertial sensors have broad application prospects both in the field of national defense and civilian areas. The paper relies on the going project of the laboratory which is low-cost shipborne satellite antenna micro attitude measurement system, makes a study of correlation algorithms of an integrated attitude measurement system based on MEMS inertial sensors, magnetometers and GPS, and the approach is verified to be feasible and effectiveness by simulations.The work makes a foundation for the practical application of the MEMS Attitude and Heading Reference System on the shipborne satellite antenna stable system.(1) The large random drift of MEMS gyro is the great factor on impacting the accuracy of attitude algorithm. Aiming at the unknown nature of its error model, the paper establishes a gyro random drift of ARMA models using the time series analysis through the static test data, and applied it to the compare of the following attitude estimation algorithm.(2) On the condition of without GPS, taking the characteristic of the shipborne movement and the AHRS working application requirements into account, through the theoretical analysis and the comparison of simulation results about the various attitude updating algorithms, the paper finds that the calculational complexity of the modified Rodrigues parameter algorithm is significantly smaller than the quaternion algorithm and the rotation vector algorithm, the calculational accuracy is similar to the quaternion algorithm, while overcoming redundant when using quaternion to descript the attitude. It supplies the gist for choosing the attitude updating algorithm.(3) According to the above analysis, the extended Kalman filter for attitude estimation algorithm is derived with gyro bias and the modified Rodrigues parameters for the state vector and output of accelerometers, and magnetometer for the observation vector, and used the switch between the modified Rodrigues parameters and its shadow parameters to solve the singularity problem.. The validity and superiority of the algorithm are verified by the simulation under the conditions of the whole attitude and the swing movement.(4) To checkout the applicability of the ARMA model, through the simulation of the conditions of the static and swing motions, the paper obtained the conclusion that in static condition the estimation algorithm based on the ARMA model for gyro bias has higher precision both of the attitude estimation and the gyro bias compensation than the random walk model. However, under the conditions of swing movement the accuracy is less than the estimation algorithm with the random walk model for gyro bias, while the calculating amount is larger. Therefore, the MRP EKF estimation algorithm used random walk model for gyro bias has more universality. In the precondition of adjusting the observation noise variance matrix, to minish the output error ulteriorly in the condition of the gravity and magnetic vectors are disturbed, the GPS information is introduced, and carries out a study of loosely coupled Kalman filter algorithm for MEMS AHRS/GPS integrated system, and the simulation verified the feasibility of the algorithm.更多还原