Visualizing and Analyzing Machine‐soil Interactions using Computer Vision
Visualizing and Analyzing Machine‐soil Interactions using Computer Vision
复制标题
使用计算机视觉可视化和分析机器与土壤的相互作用
DOI：
--
复制
发表时间：
2014
期刊：
影响因子：
--
通讯作者：
David S. Wettergreen
中科院分区：
文献类型：
--
作者：
K. Skonieczny;S. Moreland;V. Asnani;C. Creager;H. Inotsume;David S. Wettergreen
这项工作提出了一种可视化和分析机器-土壤相互作用的实验方法，即土壤光流技术（SOFT）。SOFT使用光流和聚类技术来处理土壤与车轮或工具相互作用的图像，这些图像来自通过土壤箱的玻璃墙拍摄的照片。它产生的结果比过去使用长曝光摄影的方法丰富得多。它实现了与粒子图像测速或粒子跟踪测速相当的性能，但不需要专门的测量设备或特别标记的土壤颗粒。该处理技术对不同土壤类型表现出稳健性。地面实况和交叉验证实验在估计土壤运动方面表现出亚像素精度。该技术应用于野外机器人研究的一个例子是详细研究斜坡攀爬和软土穿越的推-滚。推滚通过滚动其车轮的一部分来推进车辆，同时改变其轴距以保持其他车轮静止并推靠地面。实验表明，推压轧制比传统轧制获得更高的净牵引力。使用SOFT观察推压的两个方面（滚动和水平推动）表明，它们导致完全不同形式的土壤剪切（分别为“抓地力破坏”和“地面破坏”）。SOFT还演示了如何更有效地利用土壤运动的方向，通过推动水平推力比传统的滚动。正在进行的利用SOFT的工作也证明了其在研究挖掘工具相互作用，履带对车轮效率的影响以及各种其他车轮-土壤相互作用方面的潜在用途。
This work presents an experimental method for visualizing and analyzing machine‐soil interactions, namely the soil optical flow technique (SOFT). SOFT uses optical flow and clustering techniques to process images of soil interacting with a wheel or tool from photos taken through a glass wall of a soil bin. It produces results that are far richer than past approaches that utilized long‐exposure photography. It achieves a performance comparable to particle image velocimetry or particle tracking velocimetry, but without the need for specialized measurement equipment or specially marked soil particles. The processing technique demonstrates robustness to different soil types. Ground‐truth and cross‐validation experiments exhibit subpixel accuracy in estimating soil motions. An example of an application of this technique for field robotics research is the detailed study of push‐rolling for slope climbing and soft soil traverse. Push‐rolling advances a vehicle by rolling a subset of its wheels while changing its wheelbase to keep the other wheels static and pushing against the ground. Experiments show that push‐rolling achieves higher net traction than conventional rolling. Observing the two aspects of push‐rolling (rolling and horizontal pushing) using SOFT shows that they result in entirely different forms of soil shearing (“grip failure” and “ground failure,” respectively). SOFT also demonstrates how the direction of soil motion is more efficiently utilized for horizontal thrust by pushing than conventional rolling. Ongoing work utilizing SOFT has also demonstrated its potential use in studying excavation tool interactions, the effects of grousers on wheel efficiency, as well as a variety of other wheel‐soil interactions.