近年來，無人自動駕駛車為全球多國重點發展領域，對於車輛安全性能的各項改善對交通事故的減少有一定的影響力。自動駕駛也已經發展迅速，這些系統需要定位車輛位置，無論白天或晚上都要準確地被定位。我們基於機器學習的新穎雷達定位技術在不需要視覺影像的輔助下，透過深度學習技術暨光學雷達所獲得的資訊來執行定位。我們首先在所收集的光學雷達點雲資料中，確認較有代表性之特徵關鍵點，然後於每個關鍵點，收集附近64個點雲的資訊之深度學習特徵資訊，接著透過三維卷積網路得到位移機率值，最後透過時間域資訊的整合得到最終結果，完成雷達定位。為了提高我們網絡的速度，我們利用深度可分離卷積結構減少在三維卷積時的運算速度、利用時間卷積網路代替傳統在時序資料中使用的遞迴神經網路已達成快速計算。我們的實驗證明，我們的網絡在基於深度學習的雷達定位中具有好的表現。

Self-driving systems need to be able to localize its position with high accuracy regardless of whether it is during the day or night. This means because of the sensitivity to the lighting conditions, we cannot rely on ordinary cameras to sense the surrounding environment. A solution to replace the images is to use light detection and ranging sensor (LiDAR) to generate a three-dimensional point cloud of each point representing the distance to the sensor. In this paper, we propose a novel method for LiDAR localization using the three-dimensional point clouds generated by the LiDAR, a pre-build map, and a predicted pose as inputs and achieves centimeter-level localization accuracy. Our approach first selects a certain number of the online point cloud as key points. We then extract learned features from convolutional neural networks in order to train these neural networks to localize lidar. Our proposed method achieved significant improvements in terms of speed over prior state-of-the-art methods.

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