针对当前推土机在作业过程中操作复杂、施工效果评估困难等问题,基于北斗实时动态差分定位(real time kinematic,RTK)技术和运动学方程,求得推土机实时位置;提出了以推土高程和设计平面的高程差作为平整施工质量评价的方法,可直观评价...针对当前推土机在作业过程中操作复杂、施工效果评估困难等问题,基于北斗实时动态差分定位(real time kinematic,RTK)技术和运动学方程,求得推土机实时位置;提出了以推土高程和设计平面的高程差作为平整施工质量评价的方法,可直观评价施工效果,研制了驾驶引导装置,可实时显示推土机状态与施工进度。工程应用表明,该装置达到了厘米级的定位精度,定位的绝对误差小于5 cm,满足推土机精准施工的需求;车载显示终端使用RS232通信可精确获取推土机坐标、速度、航向等自身状态参数和施工数据。在实际施工场景中,该系统可有效减少驾驶员返工次数、降低劳动强度,提高了施工效率,达到了辅助施工的目的。展开更多
This paper presents the technical basis for wide area real time decimetre positioning services using multiple carrier signals transmitted by future GNSS such as modernized GPS and Compass systems. The first step is to...This paper presents the technical basis for wide area real time decimetre positioning services using multiple carrier signals transmitted by future GNSS such as modernized GPS and Compass systems. The first step is to form two ionosphere-reduced extra-widelanes (EWL) that have the minimal total noise levels in cycles, considering the effects of the ionospheric and tropospheric delays, orbital error, and phase noise terms in various observational environments. The proposed three carrier ambiguity resolution approach can determine the integer ambiguities of the selected EWL signals with geometry-free and geometry- based estimations respectively over the distances of typically hundreds of kilometres. With two ambiguity-fixed EWL signals, the kinematic positioning solutions can be achieved in decimetre level accuracy. A semi-simulation method is employed to generate three frequency Compass data to demonstrate the above expected performance for decimetre positioning services. Both theoretical and experimental results have demonstrated the overall 3D root mean square accuracy of better than 15 cm obtained through with a phase smoothing process over 120 epochs. The dominating error factor in this positioning result is the residual tropospheric biases, which would become less correlated as the baselines grow beyond hundreds of kilometres. With respect to dual-frequency based precise point positioning and wide area differential positioning solutions, a major advantage of using the third frequency signals is the convergence time being shorten from tens of minutes to a few minutes. In addition, due to the instant ambiguity resolution capability, phase breaks or cycle slips no longer affect the continuity of the solutions. This reliable decimetre positioning capability introduces a significant improvement to safety-of-life, liability-critical and professional applications.展开更多
搭载的低成本微机电系统惯性测量单元(micro-electro-mechanical system-inertial measurement unit, MEMS-IMU)的实时动态载波相位差分(real time kinematic, RTK)接收机的初始对准是一个关键的技术问题,也是目前惯导RTK的一个挑战。...搭载的低成本微机电系统惯性测量单元(micro-electro-mechanical system-inertial measurement unit, MEMS-IMU)的实时动态载波相位差分(real time kinematic, RTK)接收机的初始对准是一个关键的技术问题,也是目前惯导RTK的一个挑战。针对这个问题,提出一种基于梯度下降的惯导RTK初始对准方法,将多矢量定姿与梯度下降相融合,有效地提高了多矢量定姿的精度。通过仿真实验和现场实验验证改进算法的有效性。试验结果表明:在不使用任何附加传感器(如磁力计)的情况下,使用低成本MEMS-IMU,仅需2~3 s,就可以在91%的置信度下,对中杆倾斜40°范围内RTK的测量精度达到2.5 cm,该算法的精度和收敛速度都能很好地满足惯导RTK应用的要求。展开更多
To obtain higher accuracy of information concerning boat motion, the use of global positioning system (GPS) real-time kinematic (RTK) technology was investigated. Through RTK technology, a measurement precision of th...To obtain higher accuracy of information concerning boat motion, the use of global positioning system (GPS) real-time kinematic (RTK) technology was investigated. Through RTK technology, a measurement precision of the ±1 cm range can be achieved. The research equipment included a GPS receiver and a personal digital assistant as a data control and processing unit. Real-time GPS data was captured and processed to acquire various parameters, including the boat track, velocity curve, stroke rate, and stroke distance. Using this data, the quantitative information related to rowing training can be achieved. The results are helpful for analyzing the biomechanical parameters of rowing techniques and for evaluating training efficiency.展开更多
文摘针对当前推土机在作业过程中操作复杂、施工效果评估困难等问题,基于北斗实时动态差分定位(real time kinematic,RTK)技术和运动学方程,求得推土机实时位置;提出了以推土高程和设计平面的高程差作为平整施工质量评价的方法,可直观评价施工效果,研制了驾驶引导装置,可实时显示推土机状态与施工进度。工程应用表明,该装置达到了厘米级的定位精度,定位的绝对误差小于5 cm,满足推土机精准施工的需求;车载显示终端使用RS232通信可精确获取推土机坐标、速度、航向等自身状态参数和施工数据。在实际施工场景中,该系统可有效减少驾驶员返工次数、降低劳动强度,提高了施工效率,达到了辅助施工的目的。
基金financial supports from the Austrialia Cooperative Research Centre for Spatial Information (CRCSI) Project (Grant No. P1.04)the Key Laboratory of Advanced Engineering Sur-veying of SBSM (Grant No. TJES0809)
文摘This paper presents the technical basis for wide area real time decimetre positioning services using multiple carrier signals transmitted by future GNSS such as modernized GPS and Compass systems. The first step is to form two ionosphere-reduced extra-widelanes (EWL) that have the minimal total noise levels in cycles, considering the effects of the ionospheric and tropospheric delays, orbital error, and phase noise terms in various observational environments. The proposed three carrier ambiguity resolution approach can determine the integer ambiguities of the selected EWL signals with geometry-free and geometry- based estimations respectively over the distances of typically hundreds of kilometres. With two ambiguity-fixed EWL signals, the kinematic positioning solutions can be achieved in decimetre level accuracy. A semi-simulation method is employed to generate three frequency Compass data to demonstrate the above expected performance for decimetre positioning services. Both theoretical and experimental results have demonstrated the overall 3D root mean square accuracy of better than 15 cm obtained through with a phase smoothing process over 120 epochs. The dominating error factor in this positioning result is the residual tropospheric biases, which would become less correlated as the baselines grow beyond hundreds of kilometres. With respect to dual-frequency based precise point positioning and wide area differential positioning solutions, a major advantage of using the third frequency signals is the convergence time being shorten from tens of minutes to a few minutes. In addition, due to the instant ambiguity resolution capability, phase breaks or cycle slips no longer affect the continuity of the solutions. This reliable decimetre positioning capability introduces a significant improvement to safety-of-life, liability-critical and professional applications.
文摘搭载的低成本微机电系统惯性测量单元(micro-electro-mechanical system-inertial measurement unit, MEMS-IMU)的实时动态载波相位差分(real time kinematic, RTK)接收机的初始对准是一个关键的技术问题,也是目前惯导RTK的一个挑战。针对这个问题,提出一种基于梯度下降的惯导RTK初始对准方法,将多矢量定姿与梯度下降相融合,有效地提高了多矢量定姿的精度。通过仿真实验和现场实验验证改进算法的有效性。试验结果表明:在不使用任何附加传感器(如磁力计)的情况下,使用低成本MEMS-IMU,仅需2~3 s,就可以在91%的置信度下,对中杆倾斜40°范围内RTK的测量精度达到2.5 cm,该算法的精度和收敛速度都能很好地满足惯导RTK应用的要求。
文摘To obtain higher accuracy of information concerning boat motion, the use of global positioning system (GPS) real-time kinematic (RTK) technology was investigated. Through RTK technology, a measurement precision of the ±1 cm range can be achieved. The research equipment included a GPS receiver and a personal digital assistant as a data control and processing unit. Real-time GPS data was captured and processed to acquire various parameters, including the boat track, velocity curve, stroke rate, and stroke distance. Using this data, the quantitative information related to rowing training can be achieved. The results are helpful for analyzing the biomechanical parameters of rowing techniques and for evaluating training efficiency.
