Aircraft Pose Estimation Based on Geometry Structure Features and Line Correspondences

et al. 2023

Sensors

To achieve automatic disc cutter replacement of shield machines, measuring the accurate pose of the disc cutter holder by machine vision is crucial. However, under polluted and restricted illumination conditions, achieving pose estimation by vision is a great challenge. This paper proposes a line-features-based pose estimation method for the disc cutter holder of the shield machine by using a monocular camera. For the blurring effect of rounded corners on the image edge, a rounded edge model is established to obtain edge points that better match the 3D model of the workpiece. To obtain the edge search box corresponding to each edge, a contour separation method based on an adaptive threshold region growing method is proposed. By preprocesses on the edge points of each edge, the efficiency and the accuracy of RANSAC linear fitting are improved. The experimental result shows that the proposed pose estimation method is highly reliable and can meet the measurement accuracy requirements in practical engineering applications.

Section: Introductionmentioning

confidence: 99%

Line-Features-Based Pose Estimation Method for the Disc Cutter Holder of Shield Machine

Xie

Zhu

et al. 2023

Sensors

“…The artificial marks processed on the disc cutter or its holder are easy to be worn; thus, the noncooperative target method is more suitable for the actual situation. Usually, some prominent geometric features with simple structure and easy recognition are extracted from the object for positioning, such as point [5], straight line [6], circle [7], etc. By using the corner points on the inside contour of the cutter holder, feature points are extracted to estimate the pose of the cutter holder.…”

Section: Introductionmentioning

confidence: 99%

Pose Determination of the Disc Cutter Holder of Shield Machine Based on Monocular Vision

Peng

Zhu

et al. 2022

Sensors

The visual measurement system plays a vital role in the disc cutter changing robot of the shield machine, and its accuracy directly determines the success rate of the disc cutter grasping. However, the actual industrial environment with strong noise brings a great challenge to the pose measurement methods. The existing methods are difficult to meet the required accuracy of pose measurement based on machine vision under the disc cutter changing conditions. To solve this problem, we propose a monocular visual pose measurement method consisting of the high precision optimal solution to the PnP problem (OPnP) method and the highly robust distance matching (DM) method. First, the OPnP method is used to calculate the rough pose of the shield machine’s cutter holder, and then the DM method is used to measure its pose accurately. Simulation results show that the proposed monocular measurement method has better accuracy and robustness than the several mainstream PnP methods. The experimental results also show that the maximum error of the proposed method is 0.28° in the direction of rotation and 0.32 mm in the direction of translation, which can meet the measurement accuracy requirement of the vision system of the disc cutter changing robot in practical engineering application.

“…Therefore, the line features are more stable in complex environment, so as to the algorithm based on line features has attracted more and more attention. 12 –16 Xu et al 16 –18 independently estimated the landing attitude of unmanned aerial vehicle (UAV) by using the actual shape of the ground cooperative target and shadow line features and verified that the attitude estimation using line features has higher accuracy and reliability than point features. Li et al 19 proposed a point-line stereo visual simultaneous localization and mapping (SLAM) system with semantic invariants.…”

Section: Introductionmentioning

confidence: 99%

Research on solving heading attitude of airdrop cargo platform based on line features

International Journal of Advanced Robotic Systems

et al. 2022

The present study envisages the development of an improved line features method to accurately estimate the attitude of the airdrop cargo platform during airdrop landing. Therefore, this article uses the geometric characteristics of the line features to improve the traditional line features extraction and removes the locally dense line features in the image, which greatly reduces the number of line features in the image. Then, the improved random sample consensus is used to remove the mismatching of line features, which improves the real-time performance of the algorithm and the accuracy of the attitude angle, and makes up for the problem of difficult extraction of point features or low matching accuracy in the airdrop environment. Finally, a constraint equation is established for the line features that are successfully matched, and using homography to obtain attitude of the airdrop cargo platform. This article also meets the requirements of accurate calculation attitude of airdrop cargo platform. The experiment shows the significance and feasibility of the airdrop cargo platform heading and attitude calculation technology based on the line feature, and it has a good application prospect.