【作者】 陈丹；

【导师】 赵美蓉；

【作者基本信息】 天津大学 ， 仪器仪表工程， 2012， 硕士

【摘要】 陀螺经纬仪作为一种具备全天候自主定向、高精度的精密测量仪器,在测绘、军事、航空和航天等领域有着广泛的应用。目前,国外的陀螺技术很先进,已经实现陀螺经纬仪的全自动寻北测量,但是国产的陀螺经纬仪多数还需要人工的干预才能完成寻北测量。因此研究全自动、“一键寻北”的陀螺经纬仪,是具有非常重要的意义的。论文从陀螺的寻北原理出发,研究分析了几种常用的寻北算法,开发了一种高效的寻北算法,并设计了基于双单片机系统的自反馈控制寻北系统。论文的主要内容如下:1.设计实现了基于趋势预测的误差补偿多级步进初寻北算法。主单片机实时地采集陀螺光标的位置信号,并通过USB实时地传递给PC机,PC机对数据进行误差补偿的预测寻北算法,得到预测结果N1后根据补偿函数查询得到补偿角度N′,将实际寻北结果(N1+ N′)发送给主单片机,然后主单片机控制精密电控转台将陀螺经纬仪转到相应的位置,这样一次寻北结束。2.设计方案完成双单片机控制系统,实现了两个单片机之间的异步串行通信。从单片机触发步进电机自动下放陀螺,同时主单片机实时采集监测陀螺光标的运动信息,并经USB上传至PC机进行寻北结果的计算,PC机回传结果给主单片机后,主单片机控制转台做相应的旋转,进一步逼近真北方向。如此进行几次即可完成初寻北过程。3.设计并实现了自反馈控制寻北系统,首先建立了陀螺光标信号的初始位置与半脱位置之间的函数关系,其次,确定双单片机系统之间的反馈信号——半脱位置。在陀螺下放过程中,主单片机不断地查询判断,当光标信号的变化满足这一函数关系时,即代表陀螺到达半脱位置,此时主单片机将该信号反馈给从单片机,从单片机控制步进电机停止下放陀螺。这样提高了陀螺下放的质量,有效的将陀螺摆幅控制在有效的范围内。4.完成了双单片机自反馈系统的系统软件编程并验证了该系统的有效性和稳定性,其初寻北时间在4min内,初寻北误差最大均值为15′35″,标准偏差最大为5′35″,提高了初寻北速度和精度。更多还原

【Abstract】 As an all-weather and self-orientation fine measuring instrument, gyro-theodolite is widely used in surveying and mapping, military, aerospace, etc. At present, the foreign gyro technology is very advanced, and has been seeking to achieve automatic north-seeking measurement of the gyro, but the majority of the domestic gyro theodolite needs manual intervention to complete the north-seeking. Therefore, the study of the automatic and“a key north-seeking”gyro theodolite is a very important significance.A high-efficiency north-seeking algorithm is proposed in terms of gyro principle and some common north-seeking algorithm, and the feedback control system based on the double MCU system is designed. The main research contents of the paper are as follows:1. The error compensation multi-stepping rough north-seeking method based on trend forecast is put forward. The main MCU real-time collects the movement information of the gyro cursor, and delivers the data to the PC by USB, and then PC calculates the result of the north-seeking with the algorithm of the error compensation multi-stepping rough north-seeking method based on trend forecast and gets the predicted result N1 and the compensation point N′by the compensation function ;then the actual result(N1+ N′) is sent to the main MCU ;At last the main MCU control the turntable to rotate the appropriate location.2. The double MCU system is designed and completed, and the asynchronous serial communication between the two MCU is achieved. The stepper motor is triggered by the slave MCU and automatically delegates, while the main MCU real-time collects and monitors the movement information of the gyro cursor, and uploads the data to the PC via USB to calculate the result. And then the result is conveyed to the main MCU to control the turntable to rotate according to the result. This can be completed the process of the north-seeking after several the above process.3. The self-feedback control of the north-seeking system is designed and implemented. First, the function relation between the initial position of the gyro cursor and the half off position is established; secondly, the feedback signal between the double MCU system-half off position is determined. During the process of the gyro downing, the main MCU constantly checks the changes of the cursor, when the change of the cursor meets the function, which represents the gyro arriving the half off position; then the main MCU delivers the feedback signal to the slave MCU to make the stepper motor stop. The system not only increases the quality of the gyro downing, but also effectively controls the gyro swing within the effective range.4. The software programming of the feedback system is completed, and the effectiveness and stability of the system is verified by experiments. Through rough north-seeking experiments in many orientations, it is proved that the north-seeking time of the system is within 4 min; in different initial azimuth, the max average of the north-seeking error is about 15′35″,the maximum of the standard deviation is about 5′35″,which greatly improves the rough north-seeking speed and accuracy.更多还原