基于IMU和GPS数据融合的自车定位

在上一篇博文《动手学无人驾驶（5）：多传感器数据融合》介绍了如何使用Radar和LiDAR数据对自行车进行追踪，这是对汽车外界运动物体进行定位。
对于自动驾驶的汽车来说，有时也需要对自身进行更精确的定位，今天就介绍如何使用IMU和GPS进行自车定位（因为在上一篇文章中对kalman和Extend Kalman原理进行了比较详细的介绍，本文中理论部分不会再介绍的这么详细了，有需要的话可以回看上文）。
本文参考了Coursera自动驾驶课程项目，在此表示感谢。

大家可以先看看下面这个视频，对本项目要介绍的内容有个初步了解，视频链接为：https://www.bilibili.com/video/BV1cE411D7Y9?p=18

1.IMU简介

惯性测量单元（Inertial Measurement Unit）通常指由3个加速度计和3个陀螺仪组合而成，加速度计和陀螺仪安装在互相垂直的测量轴上，这里可以将其输出看作为三个方向的加速度和角速度，表示为：

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margin-left: -0.02691em; margin-right: 0.05em;"><span class="pstrut" style="height: 2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathdefault mtight" style="margin-right: 0.03588em;">y</span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height: 0.286108em;"><span class=""></span></span></span></span></span></span></span></span><span class="" style="top: -0.01em;"><span class="pstrut" style="height: 3em;"></span><span class="mord"><span class="mord"><span class="mord mathdefault" style="margin-right: 0.02691em;">w</span><span class="msupsub"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height: 0.151392em;"><span class="" style="top: -2.55em; margin-left: -0.02691em; margin-right: 0.05em;"><span class="pstrut" style="height: 2.7em;"></span><span class="sizing reset-size6 size3 mtight"><span class="mord mathdefault mtight" style="margin-right: 0.04398em;">z</span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height: 0.15em;"><span class=""></span></span></span></span></span></span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height: 3.35em;"><span class=""></span></span></span></span></span></span></span><span class="mclose"><span class="delimsizing mult"><span class="vlist-t vlist-t2"><span class="vlist-r"><span class="vlist" style="height: 3.85599em;"><span class="" style="top: -0.44997em;"><span class="pstrut" style="height: 3.155em;"></span><span class="delimsizinginner delim-size4"><span class="">⎦</span></span></span><span class="" style="top: -1.60497em;"><span class="pstrut" style="height: 3.155em;"></span><span class="delimsizinginner delim-size4"><span class="">⎥</span></span></span><span class="" style="top: -2.20597em;"><span class="pstrut" style="height: 3.155em;"></span><span class="delimsizinginner delim-size4"><span class="">⎥</span></span></span><span class="" style="top: -2.80697em;"><span class="pstrut" style="height: 3.155em;"></span><span class="delimsizinginner delim-size4"><span class="">⎥</span></span></span><span class="" style="top: -3.40797em;"><span class="pstrut" style="height: 3.155em;"></span><span class="delimsizinginner delim-size4"><span class="">⎥</span></span></span><span class="" style="top: -4.00897em;"><span class="pstrut" style="height: 3.155em;"></span><span class="delimsizinginner delim-size4"><span class="">⎥</span></span></span><span class="" style="top: -4.60997em;"><span class="pstrut" style="height: 3.155em;"></span><span class="delimsizinginner delim-size4"><span class="">⎥</span></span></span><span class="" style="top: -5.85599em;"><span class="pstrut" style="height: 3.155em;"></span><span class="delimsizinginner delim-size4"><span class="">⎤</span></span></span></span><span class="vlist-s">​</span></span><span class="vlist-r"><span class="vlist" style="height: 3.35005em;"><span class=""></span></span></span></span></span></span></span></span></span></span></span></span><br> <img src="https://img-blog.csdnimg.cn/20201122211224765.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NnMTI5MDU0MDM2,size_16,color_FFFFFF,t_70#pic_center" alt="在这里插入图片描述"></p>