积分时间对TOF激光雷达测距误差影响

Effect of Integration Time on TOF LiDAR Ranging Error

结合飞行时间(time of flight,TOF)激光雷达测距的原理和基本模型,着重分析积分时间对于测距误差的影响。TOF激光雷达采集的原始数据包含噪声,故按照如下方法对数据进行处理:(1)利用上位机软件采集TOF激光雷达在不同积分时间下的原始数据;(2)采用均值滤波算法对采集得到的原始数据进行预处理,降低噪声导致的误差;(3)根据信号相对强度进一步滤除低幅值的像素区域,选取有效区域的数据,并根据选取的有效区域进行距离的计算;(4)根据计算结果详细分析不同积分时间对测距误差的影响。在固定距离为0.6 m时,TOF激光雷达测距在最佳积分时间下平均绝对误差下降为22 mm,误差下降率为97.23%,均方根误差为0.8 mm;在0.3~1.0 m的不同距离下,误差下降率达到97%以上,测距准确度大大增加。

Combining the principle and basic model of time of flight(TOF)LiDAR ranging,we focus on the effect of integration time as a factor on the ranging error.The raw data collected by TOF LiDAR contains noise,so the data is processed according to the following method.Firstly,the raw data of TOF LiDAR under different integration times are collected using the upper computer software.Secondly,the average filtering algorithm is used to pre-process the acquired raw data to reduce the error caused by noise.Then,the pixel areas with low amplitude are further filtered out according to the relative signal strength,and the data of the valid areas is selected,and the distance is calculated according to the selected valid areas.Finally,the influence of different integration times on the ranging error is analyzed in detail according to the calculation results.At a fixed distance of 0.6 m,the average absolute error of TOF LiDAR ranging under the best integration time decreases to 22 nm,the error decrease rate is 97.23%,the root mean square error is 0.8 mm;at different distances from 0.3 m to 1.0 m,the error reduction rate could reach more than 97%.And the accuracy of ranging is greatly increased.