基于微机械加速度计的无陀螺捷联惯性技术研究

发布时间：2018-06-06 07:10

本文选题：加速度计 + 无陀螺捷联系统　；参考：《哈尔滨工程大学》2014年硕士论文

【摘要】：微惯性导航系统(MINS)是由MEMS陀螺和加速度计构成的导航系统,然而由于MEMS陀螺的漂移较大,并且陀螺的抗冲击能力差,导致由其构成的MINS精度比较低,无法单独使用。而与MEMS陀螺相比较,MEMS加速度计的精度相对较高,并且成本相对较低、稳定性好、使用时间相对较长、功耗小等特点,因此本文采用由MEMS加速度计来构成的无陀螺微惯性导航系统的惯性测量单元。本课题是基于微机械加速度计的无陀螺捷联惯性技术研究,并验证其是否可行,用微机械加速度计来构成无陀螺捷联惯性导航系统,通过基于DSP+FPGA的硬件平台采集6路安放在载体非质心处的高精度MEMS加速度计信息,以代替陀螺来测量载体角运动信息,最终经过DSP进行解算来实现系统的导航定位定姿。本文首先介绍无陀螺捷联惯导的理论基础,通过和有陀螺捷联惯性导航系统的工作方式进行比较发现无陀螺捷联惯导系统的工作原理和有陀螺捷联惯性导航系统的工作原理是相类似的。其次对六个微机械加速度计在载体上的固定方式进行设计,根据载体非质心处的比力信息可求得载体的质心处的比力和绕质心的转动角加速度,进而解算出由载体质心对地线加速度和载体绕质心的转动角速度,采用FPGA来完成6路MEMS加速度信号的采集,并对FPGA的外围电路进行了具体的设计。并且根据本文的硬件系统设计了标定方案,对安装在载体非质心处的六个微机械加速度计进行误差标定,以及设计了角速度解算方法,最后通过导航解算得到载体的姿态,导航解算由DSP完成。其次设计系统的总体方案并对主要器件进行选型,在完成上述工作后,将要对硬件电路进行设计,并对系统的软件部分进行设计,软件设计部分主要包括对各模块的编程,本文采用的编程语言是C语言。最终根据实验室现有的条件设计了具体的实验方案,根据实验数据进行仿真分析,其结果验证本课题设计的基于微机械加速度计的无陀螺捷联惯导系统在理论上是可行的。
[Abstract]:Micro inertial navigation system (MEMS) is a navigation system composed of MEMS gyroscope and accelerometer. However, because of the large drift of MEMS gyroscope and the poor impact resistance of MEMS gyroscope, the precision of MINS constituted by MEMS gyroscope is low and can not be used alone. Compared with MEMS gyroscope, the accelerometer has higher precision, lower cost, better stability, longer service time and lower power consumption. Therefore, the inertial measurement unit of gyroscope free micro inertial navigation system is used in this paper, which is composed of MEMS accelerometer. This paper is based on the research of gyroscope-free strapdown inertial technology based on micromechanical accelerometers, and verifies whether it is feasible to use micromechanical accelerometers to construct gyroscope-free strapdown inertial navigation system. Through the hardware platform based on DSP FPGA to collect the high-precision MEMS accelerometer information placed in the non-centroid of the carrier, instead of the gyroscope to measure the angular motion information of the carrier, finally through the DSP solution to achieve the navigation positioning and attitude determination of the system. This paper first introduces the theoretical basis of gyroscope-free strapdown inertial navigation. It is found that the principle of gyroscope free strapdown inertial navigation system is similar to that of gyroscopic strapdown inertial navigation system by comparing with that of gyroscope strapdown inertial navigation system. Secondly, the fixed mode of six micro-mechanical accelerometers on the carrier is designed. According to the specific force information of the non-centroid of the carrier, the specific force at the center of mass and the angular acceleration of rotation around the center of mass can be obtained. Then, the acceleration of ground wire and the rotation rate of carrier around the center of mass are calculated by the carrier centroid, and the FPGA is used to complete the acquisition of six MEMS acceleration signals, and the peripheral circuit of FPGA is designed in detail. According to the hardware system of this paper, the calibration scheme is designed, the error calibration of the six micro-mechanical accelerometers installed in the non-centroid of the carrier is carried out, and the angular velocity calculation method is designed. Finally, the attitude of the carrier is obtained through the navigation solution. The navigation solution is completed by DSP. Secondly, the overall scheme of the system is designed and the main devices are selected. After completing the above work, the hardware circuit will be designed, and the software part of the system will be designed. The software design part mainly includes the programming of each module. The programming language used in this paper is C language. Finally, according to the existing conditions in the laboratory, a specific experimental scheme is designed. The simulation results show that the gyroscope free strapdown inertial navigation system based on micro-mechanical accelerometer is feasible in theory.
【学位授予单位】：哈尔滨工程大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN96

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