2024-03-29T02:08:35Z
https://repository.dl.itc.u-tokyo.ac.jp/oai
oai:repository.dl.itc.u-tokyo.ac.jp:00002425
2022-12-19T03:44:13Z
34:105:330
9:233:280
描画ロボット : 視覚に基づく高レベルプランニング
Robot Painter : High-Level Planning Based on Visual Perception
Ruchanurucks, Miti
6685
548
Robotics
Segmentation
Color reduction
Clustering
Orientation
Manipulation
Trajectory planning
B-spline
University of Tokyo (東京大学)
博士(情報理工学)
Recently, many areas of research on humanoid robots have been studied, such as motion control, man-machine interfaces, artificial intelligence (AI), and so on. Among them many research projects have tried to create artist robots, with the common objective of exploring new sensing, artificial intelligence, and manipulation techniques. The research described in this paper explores new vision and manipulation techniques through painting tasks. The ultimate goal is to create a robot painter that has capabilities similar to those of human artists. Regarding vision, the key problems of 2D/3D object segmentation, color perception, orientation mapping, and geometric edge processing are directly addressed by our method. This research focuses, first, on an effective 2D segmentation scheme using local and global classifiers. Our proposed method can effectively deal with a foreground cut, multiple cuts, and cut before matting. Then it is shown how to exploit normal stereo cameras to roughly extract the object automatically, based on 3D background subtraction and other vision techniques, and how to use our 2D segmentation to extract the object area correctly. The robot must analyze color distribution of the object to select the best set of colors to use. Normally, clustering colors face the tendency to produce colors with low contrast. We solve this problem by incorporating two clustering methods: maximum distance clustering and K-means. Then, in order to draw brush strokes meaningfully, the robot senses the orientation of the object. To smooth the orientation of the whole object, we apply global orientation that exploits the radial basis function to generate a style similar to Van Gogh, for instance, for the entire object. Furthermore, some human artists usually use edges to enhance their paintings. Technically, many researchers use gradient information to represent edges of objects. However, this would be affected by the color information on the surface. Hence, we decided to use 3D geometric edges as an input. We then extract 2D edges from the 3D model. Finally, the 2D edges are processed into brush strokes. We show how to apply these methods to high-level manipulation using a robot platform that consists of two arms and multi-fingered hands. The robot also has a stereo vision system. Based on the derived information, the robot then performs a visual feedback drawing. First, it detects a brush and grabs it using cameras and force sensors. Second, it calculates the position of the brush tip using principal component analysis (PCA). Third, it then draws and compares the canvas with the picture produced by the stereo cameras. Finally, as the trajectories planned by the robot may not be realized on the real robot platform because of its physical limitations, this research presents a method to filter and optimize trajectories targeting offline and online applications. All physical attributes, namely angle, collision, velocity, and dynamic force, are considered as a set of constraints to be met and represented as B-spline coefficients, making the limits guaranteed. The proposed method will be shown to outperform the current methods in the sense of correctness and minimal user interaction, and it does so in a reasonable computation time.
thesis
2008-03
2008-03-24
application/pdf
甲第23947号
https://repository.dl.itc.u-tokyo.ac.jp/record/2425/files/48057414.pdf
eng