TCM3电子罗盘的特性与应用

电子罗盘正广泛应用于各类导航定位系统中。介绍了TCM3电子罗盘的特性,详细说明了TCM3的控制编程和航向、俯仰、横滚等参数的读取,利用TCM3和GPS组合实现在农业机器人控制平台上的导航应用。经试验测试,TCM3在农业机器人导航平台上航向精度为±1℃,能够满足大部分精准农业应用的需要。     

磁阻式电子罗盘的设计

通过对磁阻式电子罗盘工作原理的介绍,设计了一套利用磁阻传感器和加速度计测定航向角、俯仰角、侧滚角的电子罗盘测量系统;分析了影响磁阻式电子罗盘测量精度的误差来源,并在此基础上提出了基于牛顿迭代算法的校正方法;最后,经实验结果表明,利用这些校正算法,可使电子罗盘的航向角误差由±9o降到±0.6o,有效地减低由于制造和安装等所引起的误差;同时,这种校正算法不仅适用于电子罗盘,也适用于其它3轴传感器系统。     

三维磁阻式电子罗盘的设计与实现

所设计的三维磁阻式电子罗盘的硬件方面是由三维磁阻传感器HMC5883l(深圳市凡高科技有限公司)、三维加速度传感器ADXL345B(深圳市创联发科技有限公司)以及微处理器MCU LPC1114FBD48(NXP公司)所组成,来测定系统的航向角、俯仰角和翻滚角。软件方面,通过对误差来源的分析,提出了椭圆拟合误差校正方法,来消除影响罗盘测量精度的误差,实现了高精度、运行稳定的三维电子罗盘。     

无航向基准条件下电子罗盘的误差补偿方法研究

针对HMR3300电子罗盘在实际使用时,航向角测量精度低问题,探讨有效的磁差补偿方法.在分析电子罗盘航向角测量误差产生机理的基础上,建立了无航向基准条件下电子罗盘的误差校正模型,推导了自差补偿系数的计算公式,实验结果表明该补偿方法是正确有效的,可将HMR3300的航向角测量误差控制在0.5°之内.     

基于MEMS器件的电子罗盘系统设计

研究了一种基于MEMS加速度传感器、三轴磁阻传感器和MSP430F169单片机的数字电子罗盘测量系统。介绍了航向的测量原理、航向角表达式以及系统的整体框架,重点阐述了系统的硬件电路设计和误差补偿方法,使罗盘系统精度最大误差从41.5°提高到了1.5°左右。     

电子罗盘的航向数据的修正

电子磁罗盘作为天线座架栽体姿态的测量装置，提供载体的航向、横摇、纵摇等姿态信息。依据罗盘提供的横摇、纵摇以及当前的栽体角计算出当前的航向角，用它与罗盘提供的航向角的差值修正罗盘提供的航向角．可获得较高精度的航向角，并提高系统的快速性。     

三轴磁罗盘的设计与误差校正

介绍了三轴磁罗盘的工作原理,设计了一种利用磁阻传感器和加速度计测定航向角、俯仰角、侧滚角的测量系统.分析了影响磁罗盘测量精度的误差来源,并在此基础上提出了相应的校正方法.实验结果表明,利用这些算法,可使磁罗盘的航向角误差由±9°降到±0.6°,有效地降低了由于制造和安装等引起的误差.这种校正算法不仪适用于磁罗盘,也适用于其它三轴传感器系统.     

三维磁阻式电子罗盘的研制

利用三轴磁阻传感器和两轴倾角传感器研制三维磁阻式电子罗盘.三轴磁阻传感器HMC1043测量地磁场的3个分量,倾角传感器SCA100T测量罗盘的翻滚角和俯仰角,2只传感器的信号经过电路处理后传入单片机中,再通过RS-232接口输入到计算机进行计算处理,计算机终端采用VC编制的界面来显示罗盘的方位角和翻滚、俯仰角.系统采用了低功耗的置位/复位电路来保证磁阻传感器的灵敏度.最终电子罗盘的方位角精度达到0.5°,方位角分辨率达到0.1°.     

电子罗盘水平状态下航向角误差补偿算法的研究

针对电子罗盘测量时存在传感器的零位、灵敏度误差和干扰磁场引起的航向角误差问题,应用一种航向角误差补偿算法进行校正;在分析了电子罗盘航向角测量的工作原理、航向角误差形成原因的基础上,详细阐述了该补偿算法的实现原理,并通过LbVIEW软件仿真验证;同时设计了两种测量方案和测试系统,利用HMC1043芯片的电子罗盘进行多次实测验证并得出结论;实验结果表明:补偿后电子罗盘测量的航向角误差在4.5°以内;该补偿算法补偿效果良好,实现简单。     

陀螺经纬仪自动粗寻北系统的设计研究

提出了一种利用电子罗盘实现陀螺经纬仪粗寻北自动化方案。通过分析电子罗盘的原理和影响其精度的因素,对电子罗盘进行了校准。设计了基于DSP的控制电路,根据电子罗盘的输出驱动系统指向粗北方向。实验结果表明：电子罗盘粗寻北系统的精度在±30’以内,完全满足使用要求,粗寻北时间由10-15min减少到1-2min。     

基于恒定姿态误差的磁罗差偏差补偿算法研究

针对具有恒定俯仰角度载体的磁航向罗差标定和补偿问题,提出了一种用于磁罗差修正的偏差补偿算法(DCA)。通过DCA的原理分析和证明得出:该算法对具有恒定横滚角度和俯仰角度的磁航向罗差修正均有效,经过DCA补偿的磁航向角度误差在±0.3°以内,满足飞机的航向标定要求。     

无磁转台的电子罗盘误差分离标定方法

采用3个分立的磁感式磁传感器和三轴加速度传感器制作了全数字输出电子罗盘;基于自制三轴旋转无磁转台提出了一种电子罗盘标误差分离标定方法.通过无磁转台获取磁传感器敏感轴非正交或未对准的参数和磁传感器输出特性曲线,磁传感器的灵敏度系数因子和偏置量.分别评价偏置、灵敏度系数不一致以及非正交或未对准对电子罗盘方位角精度的影响.实验结果表明:经过校准后,电子罗盘水平面内误差不超过0.22°,而俯仰角和翻滚角在60°内时,方位角最大误差约为0.4°,说明了标定方法的有效性.     

基于系统芯片(SoC)的低成本电子罗盘的设计

航向与姿态是物体运动轨迹的重要参数,其测量方法一直是导航领域的研究重点.以系统芯片为核心,设计了基于磁阻传感器与MEMS加速度计的全芯片化电子罗盘,并实现了全部信号的无缝直连,最大化地减少了外围器件的使用,其设计使结构简单,降低了成本、体积和功耗,增强了抗干扰的能力.本设计给出了航向角与姿态角的实现算法,分析了电子罗盘的误差,提出了元件级和系统级的误差补偿方法,并提出了一种7项罗差校正公式.经试验证明,系统性能稳定,性价比高,其微型的体积,适合于低速的便携导航应用.     

基于RBF神经网络的全姿态磁航向误差建模与补偿

对磁罗盘系统误差和目前多数文献所提出的全姿态磁航向误差补偿方法的不足进行了分析.针对具有一定俯仰角或横滚角的磁罗盘系统磁航向误差建模和补偿问题,提出了基于径向基函数(RBF)神经网络的修正方法,并与BP神经网络方法进行了比较.在分析算法原理的基础上进行了实验仿真,结果表明:采用RBF神经网络在明显提高网络收敛速度的基础上,大大减小了全姿态磁航向误差,校正效果优于BP神经网络.     

CORDIC算法在三轴电子罗盘中的应用

CORDIC算法是用于计算三角、反三角、指数、对数等超越函数的简捷算法。将该算法应用在以单片机为核心的三轴电子罗盘中,用于实现罗盘的倾斜补偿并计算俯仰角、横滚角和航向角。实验表明,该算法可有效地在单片机上运行,能够较好地兼顾计算精度与效率,有实用价值。     

All terrain vehicle loss of control events in agriculture: Contribution of pitch,roll and velocity

All terrain vehicle (ATV) (i.e. quad bike) loss of control (LOC) events are a major cause of injury and death on New Zealand and Australian farms. ATV LOC history, work experience, anthropometric data and vehicle pitch, roll and velocity data were recorded from 30 farmers. The terrain induced 95th percentiles were forward pitch 27.8°, backward pitch 28.7° and 20.8° for left and right roll. Nineteen participants (mean 42.4 years) had experienced 53 LOC events and were on average 9.5 years younger than the 11 participants (mean 51.9 years) who had not previously experienced LOC. Peak pitch, roll and velocity were not associated with LOC; however, at peak left roll the non-LOC group had a pitch of 3.1° downhill, while the LOC group had a pitch of 2.1° uphill. Results indicate ATV LOC prevalence is considerably underestimated, while increased risk for LOC may be influenced by a combination of personal, mechanical or terrain factors. The ATV pitch, roll and slope traverse data may help in the better understanding of why LOC events occur, may help in the development of safety equipment such as a tilt warning device and will contribute to national safety guidelines.

Statement of Relevance: Approximately 80,000 ATVs are used in rural New Zealand and ATV accidents are the single most common cause of work-related fatalities, apart from road accidents. This fieldwork research provides pitch, roll and velocity data and considers how these data might contribute to risk of ATV accidents.     

Light Chisel: 6DOF Pen Tracking

We present a novel interaction device tracked in 6 degrees of freedom by two commodity cameras. The inexpensive Light Chisel is statically illuminated with two LEDs, and uses no additional sensor (e.g. inertial or magnetic) or means of communication or synchronization. Its form factor is well suited for a screwdriver or chisel grip, allowing the Light Chisel to be rolled between the fingers. The position and orientation of the tool is tracked absolutely, making the Light Chisel suited for complex interaction, e.g. geometric modeling in augmented reality. The Light Chisel is physically small, limiting the physical and optical collisions with the real world. The orientation of the tool is tracked in a wide range of angles: pitch and yaw ±90°, roll ±180°. We evaluated our system against the OptiTrack optical tracking system. Our system achieved mean differences from OptiTrack reference of 2.07 mm in position, 1.06° in yaw and pitch, and 5.26° in roll using a pair of VGA cameras. We demonstrate usefulness of our Light Chisel in four applications: character animation, modeling by swirls, volumetric modeling, and docking of CAD models.     

Validation of in situ wave spectrum with JONSWAP in the Indian Ocean

The moored data buoys deployed by the National Institute of Ocean Technology (NIOT) are floating platforms designed to carry a specific suit of sensors to measure wave parameters. Waves are measured by the Motion Reference Unit (MRU), which outputs roll, pitch, compass, and heave. These data are recorded at a rate of 1 Hz for 17 minutes every three hours. For this study, wave measurements were carried out at two locations (deep and shallow water) over the same period. The wave spectra were generated from the hard disk data (roll, pitch, heave, and compass) of the moored buoys. A Matrix Laboratory (MATLAB) program was developed for generating the wave spectrum using the hard disk data. The spectrum exhibits significant features for deep- and shallow-water buoys. In a single peak spectrum the dominant peaks are observed at 0.08 and 0.1 Hz and the multi-peak spectrum energy is distributed over a wide range, from 0.05 to 0.25 Hz. The buoy spectra were compared to the Joint North Sea Wave Project (JONSWAP) spectrum in deep- and shallow-water locations in the Bay of Bengal, and also the deep-water buoy spectrum was compared to the wave model (WAM) output spectrum in the Arabian Sea. The JONSWAP spectrum mostly conforms to the buoy spectrum in regard to marine wind conditions.