## 2 Research Status of Key Technology for Environmental Perception of Intelligent Excavators
### Research Status of LiDAR Dust Noise Reduction Technology
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Literature** & **Keywords** & **Major Contribution** & **Time** \\ \hline
[36] & Damping table & The elastic damping damper and installation position of the damping table & 2003 \\  & & are selected according to the vibration response characteristics. & 2011 \\ \hline
[37] & Shock absorber & The shock absorber with nonlinear hysteresis characteristics is selected, & 2011 \\  & & and the layout of the shock absorber is designed. & 2011 \\ \hline
[38] & Wire rope shock absorber & A metal wire rope shock absorber is selected, a reasonable layout is & 2011 \\  & & designed, and a vibration reduction scheme for the optical platform is & 2011 \\  & & also designed. & 2014 \\ \hline
[39] & Damping table & The installation position of the platform is determined, the vibration model & 2014 \\  & & is established, and the damping table is designed. & 2020 \\ \hline
[43] & Passive vibration isolator & Through mathematical modeling, dynamic simulation, and response & \\  & & surface analysis, the structure parameters of optimal rod length, assembly & \\  & & angle, spring stiffness, and damping coefficient are selected, and a passive & 2024 \\  & & isolator mechanism based on a second-order spring damping vibration & \\  & & system is constructed. & \\ \hline
[44] & Rubber shock absorber & According to the vibration-damping design requirements, the rubber shock & \\  & & absorber was designed, and the finite element simulation method of & \\  & & rubber structural parts was summarized. According to the simulation & \\  & & requirements, the material parameters of rubber samples were tested, and & \\  & & the superelastic model parameters of rubber materials and the viscoelastic & \\  & & results of materials were obtained through the test. & \\ \hline
[45] & Multimodal vibration & According to the characteristic design and equivalent principle of the & \\  & suppression & crawler chassis of hydraulic excavators, the multi-mode vibration & \\  & & suppression algorithm is adopted to realize the multi-mode vibration & \\  & & suppression of the crawler chassis of hydraulic excavators. & \\ \hline
[46] & Finite element; & The substructure power flow method is comprehensively used to study the & \\  & & influence of vibration characteristics of the rotating platform on cab noise & \\  & & and improve the dynamic solving efficiency to accelerate the analysis and & \\  & & optimization process of excavator noise and vibration performance. & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._optical path, derived and verified the mathematical model, and simulated the signal-to-noise ratio based on this method. [PERSON] et al. [51] established a probabilistic model of the interaction between LiDAR and dust and verified the model through simulation and experiment. [PERSON] et al. [52] developed a method to measure the level of suspended dust by determining the transmission coefficient and used it for quantitative evaluation of the environmental perception performance of LiDAR. The reliability and accuracy of target detection were evaluated by conducting measurement experiments with sensors in a controlled environment. The above methods focus on evaluating the impact of smoke, dust, etc. on the sensor's environment perception through techniques such as simulation or modeling. However, all of them adopt ideal assumptions, which are difficult to meet in practical engineering applications. Because the dust will make the light emitted by the LiDAR offset, it is easy to cause the outlier. From the perspective of filtering and noise reduction, [PERSON] et al. [53] carried out filtering and noise reduction for point clouds based on a bilateral filtering algorithm while maintaining the characteristics of point clouds. The algorithm fully considered the normal variation of the surface of the point cloud model and the relationship between the distance between neighboring points and noise and realized point cloud noise reduction by adjusting the normal position of sampling points.