The main limitation to obstacle avoidance nowadays has been negative road anomalies which is the term we used to refer to potholes and cracks due to their negative drop from the surface of the road. This has for long been a limitation because of the fact that they exist in different, random and stochastic shapes. Today’s technology lacks the presence of sensors capable of detecting negative road anomalies efficiently as the latter surpasses the sensor’s limitations rendering the sensing technique inaccurate. A significant amount of research has been focused on the detection of negative road anomalies due to the fact that this topic is becoming a hot research topic. In this paper, the existing techniques will be reviewed. Their limitations will be highlighted and they will be assessed via certain performance indicators and via some chosen criteria which will be introduced.

中文翻译：

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负面道路异常检测方法综述

如今，避障的主要限制是负面道路异常，这是我们用来指代坑洼和裂缝的术语，因为它们从道路表面下降。这长期以来一直是一个限制，因为它们以不同的、随机的和随机的形状存在。当今的技术缺乏能够有效检测负面道路异常的传感器，因为后者超出了传感器的限制，导致传感技术不准确。由于该主题正在成为热门研究课题，因此大量研究都集中在检测负面道路异常上。在本文中，将回顾现有技术。