Differentiable rendering aims to compute the derivative of the image rendering function with respect to the rendering parameters. This paper presents a novel algorithm for 6-DoF pose estimation through gradient-based optimization using a differentiable rendering pipeline. We emphasize two key contributions: (1) instead of solving the conventional 2D to 3D correspondence problem and computing reprojection errors, images (rendered using the 3D model) are compared only in the 2D feature space via sparse 2D feature correspondences. (2) Instead of an analytical image formation model, we compute an approximate local gradient of the rendering process through online learning. The learning data consists of image features extracted from multi-viewpoint renders at small perturbations in the pose neighborhood. The gradients are propagated through the rendering pipeline for the 6-DoF pose estimation using nonlinear least squares. This gradient-based optimization regresses directly upon the pose parameters by aligning the 3D model to reproduce a reference image shape. Using representative experiments, we demonstrate the application of our approach to pose estimation in proximity operations.

在这项工作中，我们分析了两个卫星之间的相对姿势初始化问题：一个追逐者和一个不合作目标。该分析针对两种基于单眼摄像头系统的近距离方法：Sharma-ventura-d'amico（SVD）方法和Silhouette匹配方法。两种方法均基于对目标几何形状的先验知识，但是不需要基准标记或先验范围的测量或状态信息。测试是使用2U立方体模型进行的，该目标是连接到机动旋转阶段的目标，以模拟其相对于追赶者摄像机的相对运动。运动捕获系统用作参考仪器，该工具提供了两个模型之间的基准相对运动，并允许评估所分析的初始化算法的性能。

本文介绍了一种新型的多视图6 DOF对象姿势细化方法，重点是改进对合成数据训练的方法。它基于DPOD检测器，该检测器会在每个帧中产生密集的2D-3D对应关系。我们选择使用多个具有已知相机转换的帧，因为它允许通过可解释的ICP样损耗函数引入几何约束。损耗函数是通过可区分的渲染器实现的，并经过迭代进行了优化。我们还证明，仅根据合成数据训练的完整检测和完善管道可用于自动标记的真实数据。我们对linemod，caslusion，自制和YCB-V数据集执行定量评估，并与对合成和真实数据训练的最新方法相比，报告出色的性能。我们从经验上证明，我们的方法仅需要几个帧，并且可以在外部摄像机校准中关闭相机位置和噪音，从而使其实际用法更加容易且无处不在。

Estimating 6D poses of objects from images is an important problem in various applications such as robot manipulation and virtual reality. While direct regression of images to object poses has limited accuracy, matching rendered images of an object against the input image can produce accurate results. In this work, we propose a novel deep neural network for 6D pose matching named DeepIM. Given an initial pose estimation, our network is able to iteratively refine the pose by matching the rendered image against the observed image. The network is trained to predict a relative pose transformation using a disentangled representation of 3D location and 3D orientation and an iterative training process. Experiments on two commonly used benchmarks for 6D pose estimation demonstrate that DeepIM achieves large improvements over stateof-the-art methods. We furthermore show that DeepIM is able to match previously unseen objects.

运动结构在现实世界中非常普遍。它们范围从简单的铰接物对象到复杂的机械系统。但是，尽管它们相关，但大多数基于模型的3D跟踪方法仅考虑刚性对象。为了克服这一限制，我们提出了一个灵活的框架，该框架允许将现有的6DOF算法扩展到运动结构。我们的方法着重于采用类似牛顿的优化技术的方法，这些方法广泛用于对象跟踪中。该框架考虑了树状和封闭的运动学结构，并允许对关节和约束的灵活配置。为了从单个刚体到多体系统的项目方程式，使用了雅各布人。对于封闭的运动链，开发了一种具有Lagrange乘数的新型配方。在详细的数学证明中，我们表明我们的约束配方会导致精确的运动解，并在单个迭代中收敛。基于提出的框架，我们将ICG扩展到了最新的刚性对象跟踪算法，将其扩展到多体跟踪。为了进行评估，我们创建了一个高度现实的合成数据集，该数据集具有大量序列和各种机器人。基于此数据集，我们进行了多种实验，这些实验证明了开发框架和我们的多体跟踪器的出色性能。

We introduce MegaPose, a method to estimate the 6D pose of novel objects, that is, objects unseen during training. At inference time, the method only assumes knowledge of (i) a region of interest displaying the object in the image and (ii) a CAD model of the observed object. The contributions of this work are threefold. First, we present a 6D pose refiner based on a render&compare strategy which can be applied to novel objects. The shape and coordinate system of the novel object are provided as inputs to the network by rendering multiple synthetic views of the object's CAD model. Second, we introduce a novel approach for coarse pose estimation which leverages a network trained to classify whether the pose error between a synthetic rendering and an observed image of the same object can be corrected by the refiner. Third, we introduce a large-scale synthetic dataset of photorealistic images of thousands of objects with diverse visual and shape properties and show that this diversity is crucial to obtain good generalization performance on novel objects. We train our approach on this large synthetic dataset and apply it without retraining to hundreds of novel objects in real images from several pose estimation benchmarks. Our approach achieves state-of-the-art performance on the ModelNet and YCB-Video datasets. An extensive evaluation on the 7 core datasets of the BOP challenge demonstrates that our approach achieves performance competitive with existing approaches that require access to the target objects during training. Code, dataset and trained models are available on the project page: https://megapose6d.github.io/.

这项工作介绍了斯坦福大学的Rendezvous和光学导航（Tron）的机器人测试的最新进展 - 这是一个能够验证空间载光学导航机器学习算法的第一个机器人试验。 Tron设施包括两个6度自由的Kuka机器人武器和一组Vicon运动轨道摄像机，以重新配置相机和目标样机模型之间的任意相对姿势。该设施包括多个地球玻璃灯箱和阳光灯，以重建高保真星源照明条件。在该设施概述后，该工作详细说明了多源校准程序，使物体与相机之间的相对姿势估计，具有毫米级位置和跨越级别的方向精度。最后，使用在合成图像上预先培训的卷积神经网络（CNN）进行合成和Tron模拟成像的比较分析。结果显示了CNN性能相当大的差距，表明Tron模拟图像可用于验证从计算机图形学更容易访问的合成图像训练的任何机器学习算法的鲁棒性。

Camera pose estimation is a key step in standard 3D reconstruction pipelines that operate on a dense set of images of a single object or scene. However, methods for pose estimation often fail when only a few images are available because they rely on the ability to robustly identify and match visual features between image pairs. While these methods can work robustly with dense camera views, capturing a large set of images can be time-consuming or impractical. We propose SparsePose for recovering accurate camera poses given a sparse set of wide-baseline images (fewer than 10). The method learns to regress initial camera poses and then iteratively refine them after training on a large-scale dataset of objects (Co3D: Common Objects in 3D). SparsePose significantly outperforms conventional and learning-based baselines in recovering accurate camera rotations and translations. We also demonstrate our pipeline for high-fidelity 3D reconstruction using only 5-9 images of an object.

我们提出了一种称为DPODV2（密集姿势对象检测器）的三个阶段6 DOF对象检测方法，该方法依赖于致密的对应关系。我们将2D对象检测器与密集的对应关系网络和多视图姿势细化方法相结合，以估计完整的6 DOF姿势。与通常仅限于单眼RGB图像的其他深度学习方法不同，我们提出了一个统一的深度学习网络，允许使用不同的成像方式（RGB或DEPTH）。此外，我们提出了一种基于可区分渲染的新型姿势改进方法。主要概念是在多个视图中比较预测并渲染对应关系，以获得与所有视图中预测的对应关系一致的姿势。我们提出的方法对受控设置中的不同数据方式和培训数据类型进行了严格的评估。主要结论是，RGB在对应性估计中表现出色，而如果有良好的3D-3D对应关系，则深度有助于姿势精度。自然，他们的组合可以实现总体最佳性能。我们进行广泛的评估和消融研究，以分析和验证几个具有挑战性的数据集的结果。 DPODV2在所有这些方面都取得了出色的成果，同时仍然保持快速和可扩展性，独立于使用的数据模式和培训数据的类型

通常，非刚性登记的问题是匹配在两个不同点拍摄的动态对象的两个不同扫描。这些扫描可以进行刚性动作和非刚性变形。由于模型的新部分可能进入视图，而其他部件在两个扫描之间堵塞，则重叠区域是两个扫描的子集。在最常规的设置中，没有给出先前的模板形状，并且没有可用的标记或显式特征点对应关系。因此，这种情况是局部匹配问题，其考虑了随后的扫描在具有大量重叠区域的情况下进行的扫描经历的假设[28]。本文在环境中寻址的问题是同时在环境中映射变形对象和本地化摄像机。

我们介绍了日常桌面对象的998 3D型号的数据集及其847,000个现实世界RGB和深度图像。每个图像的相机姿势和对象姿势的准确注释都以半自动化方式执行，以促进将数据集用于多种3D应用程序，例如形状重建，对象姿势估计，形状检索等。3D重建由于缺乏适当的现实世界基准来完成该任务，并证明我们的数据集可以填补该空白。整个注释数据集以及注释工具和评估基线的源代码可在http://www.ocrtoc.org/3d-reconstruction.html上获得。

综合照片 - 现实图像和视频是计算机图形的核心，并且是几十年的研究焦点。传统上，使用渲染算法（如光栅化或射线跟踪）生成场景的合成图像，其将几何形状和材料属性的表示为输入。统称，这些输入定义了实际场景和呈现的内容，并且被称为场景表示（其中场景由一个或多个对象组成）。示例场景表示是具有附带纹理的三角形网格（例如，由艺术家创建），点云（例如，来自深度传感器），体积网格（例如，来自CT扫描）或隐式曲面函数（例如，截短的符号距离）字段）。使用可分辨率渲染损耗的观察结果的这种场景表示的重建被称为逆图形或反向渲染。神经渲染密切相关，并将思想与经典计算机图形和机器学习中的思想相结合，以创建用于合成来自真实观察图像的图像的算法。神经渲染是朝向合成照片现实图像和视频内容的目标的跨越。近年来，我们通过数百个出版物显示了这一领域的巨大进展，这些出版物显示了将被动组件注入渲染管道的不同方式。这种最先进的神经渲染进步的报告侧重于将经典渲染原则与学习的3D场景表示结合的方法，通常现在被称为神经场景表示。这些方法的一个关键优势在于它们是通过设计的3D-一致，使诸如新颖的视点合成捕获场景的应用。除了处理静态场景的方法外，我们还涵盖了用于建模非刚性变形对象的神经场景表示...

手工姿势和形状估计研究领域的数据集和工具的数量和质量作为所做的重大进展的证据。然而，即使是迄今为止报告的最高质量的数据集，也具有注释的缺点。我们提出了一种基于可分辨率的射线跟踪的细化方法，并演示了如何具有高质量的公共可用的，双摄像机数据集（Interwand2.6m）可以成为一个更好的数据集，相对于注释质量。到目前为止，迄今未采用可分辨率的射线跟踪，特此被证明优于过去已经采用的近似替代品。为了解决缺乏可靠的地面真理，就量化评估而言，我们求助于现实的合成数据，表明我们诱导的改进确实很重要。通过视觉评估，实际数据中的实际数据也是如此。

We introduce an approach for recovering the 6D pose of multiple known objects in a scene captured by a set of input images with unknown camera viewpoints. First, we present a single-view single-object 6D pose estimation method, which we use to generate 6D object pose hypotheses. Second, we develop a robust method for matching individual 6D object pose hypotheses across different input images in order to jointly estimate camera viewpoints and 6D poses of all objects in a single consistent scene. Our approach explicitly handles object symmetries, does not require depth measurements, is robust to missing or incorrect object hypotheses, and automatically recovers the number of objects in the scene. Third, we develop a method for global scene refinement given multiple object hypotheses and their correspondences across views. This is achieved by solving an object-level bundle adjustment problem that refines the poses of cameras and objects to minimize the reprojection error in all views. We demonstrate that the proposed method, dubbed Cosy-Pose, outperforms current state-of-the-art results for single-view and multi-view 6D object pose estimation by a large margin on two challenging benchmarks: the YCB-Video and T-LESS datasets. Code and pre-trained models are available on the project webpage. 5

Estimating the 6D pose of known objects is important for robots to interact with the real world. The problem is challenging due to the variety of objects as well as the complexity of a scene caused by clutter and occlusions between objects. In this work, we introduce PoseCNN, a new Convolutional Neural Network for 6D object pose estimation. PoseCNN estimates the 3D translation of an object by localizing its center in the image and predicting its distance from the camera. The 3D rotation of the object is estimated by regressing to a quaternion representation. We also introduce a novel loss function that enables PoseCNN to handle symmetric objects. In addition, we contribute a large scale video dataset for 6D object pose estimation named the YCB-Video dataset. Our dataset provides accurate 6D poses of 21 objects from the YCB dataset observed in 92 videos with 133,827 frames. We conduct extensive experiments on our YCB-Video dataset and the OccludedLINEMOD dataset to show that PoseCNN is highly robust to occlusions, can handle symmetric objects, and provide accurate pose estimation using only color images as input. When using depth data to further refine the poses, our approach achieves state-of-the-art results on the challenging OccludedLINEMOD dataset. Our code and dataset are available at https://rse-lab.cs.washington.edu/projects/posecnn/.

Affine correspondences have traditionally been used to improve feature matching over wide baselines. While recent work has successfully used affine correspondences to solve various relative camera pose estimation problems, less attention has been given to their use in absolute pose estimation. We introduce the first general solution to the problem of estimating the pose of a calibrated camera given a single observation of an oriented point and an affine correspondence. The advantage of our approach (P1AC) is that it requires only a single correspondence, in comparison to the traditional point-based approach (P3P), significantly reducing the combinatorics in robust estimation. P1AC provides a general solution that removes restrictive assumptions made in prior work and is applicable to large-scale image-based localization. We propose two parameterizations of the P1AC problem and evaluate our novel solvers on synthetic data showing their numerical stability and performance under various types of noise. On standard image-based localization benchmarks we show that P1AC achieves more accurate results than the widely used P3P algorithm.

A monocular visual-inertial system (VINS), consisting of a camera and a low-cost inertial measurement unit (IMU), forms the minimum sensor suite for metric six degreesof-freedom (DOF) state estimation. However, the lack of direct distance measurement poses significant challenges in terms of IMU processing, estimator initialization, extrinsic calibration, and nonlinear optimization. In this work, we present VINS-Mono: a robust and versatile monocular visual-inertial state estimator. Our approach starts with a robust procedure for estimator initialization and failure recovery. A tightly-coupled, nonlinear optimization-based method is used to obtain high accuracy visual-inertial odometry by fusing pre-integrated IMU measurements and feature observations. A loop detection module, in combination with our tightly-coupled formulation, enables relocalization with minimum computation overhead. We additionally perform four degrees-of-freedom pose graph optimization to enforce global consistency. We validate the performance of our system on public datasets and real-world experiments and compare against other state-of-the-art algorithms. We also perform onboard closed-loop autonomous flight on the MAV platform and port the algorithm to an iOS-based demonstration. We highlight that the proposed work is a reliable, complete, and versatile system that is applicable for different applications that require high accuracy localization. We open source our implementations for both PCs 1 and iOS mobile devices 2 .

同时定位和映射（SLAM）对于自主机器人（例如自动驾驶汽车，自动无人机），3D映射系统和AR/VR应用至关重要。这项工作提出了一个新颖的LIDAR惯性 - 视觉融合框架，称为R $^3 $ LIVE ++，以实现强大而准确的状态估计，同时可以随时重建光线体图。 R $^3 $ LIVE ++由LIDAR惯性探针（LIO）和视觉惯性探测器（VIO）组成，均为实时运行。 LIO子系统利用从激光雷达的测量值重建几何结构（即3D点的位置），而VIO子系统同时从输入图像中同时恢复了几何结构的辐射信息。 r $^3 $ live ++是基于r $^3 $ live开发的，并通过考虑相机光度校准（例如，非线性响应功能和镜头渐滴）和相机的在线估计，进一步提高了本地化和映射的准确性和映射接触时间。我们对公共和私人数据集进行了更广泛的实验，以将我们提出的系统与其他最先进的SLAM系统进行比较。定量和定性结果表明，我们所提出的系统在准确性和鲁棒性方面对其他系统具有显着改善。此外，为了证明我们的工作的可扩展性，{我们基于重建的辐射图开发了多个应用程序，例如高动态范围（HDR）成像，虚拟环境探索和3D视频游戏。}最后，分享我们的发现和我们的发现和为社区做出贡献，我们在GitHub上公开提供代码，硬件设计和数据集：github.com/hku-mars/r3live

本文提出了一种类别级别的6D对象姿势和形状估计方法IDAPS，其允许在类别中跟踪6D姿势并估计其3D形状。我们使用深度图像作为输入开发类别级别自动编码器网络，其中来自自动编码器编码的特征嵌入在类别中对象的姿势。自动编码器可用于粒子过滤器框架，以估计和跟踪类别中的对象的姿势。通过利用基于符号距离函数的隐式形状表示，我们构建延迟网络以估计给定对象的估计姿势的3D形状的潜在表示。然后，估计的姿势和形状可用于以迭代方式互相更新。我们的类别级别6D对象姿势和形状估计流水线仅需要2D检测和分段进行初始化。我们在公开的数据集中评估我们的方法，并展示其有效性。特别是，我们的方法在形状估计上实现了相对高的准确性。

现代计算机视觉已超越了互联网照片集的领域，并进入了物理世界，通过非结构化的环境引导配备摄像头的机器人和自动驾驶汽车。为了使这些体现的代理与现实世界对象相互作用，相机越来越多地用作深度传感器，重建了各种下游推理任务的环境。机器学习辅助的深度感知或深度估计会预测图像中每个像素的距离。尽管已经在深入估算中取得了令人印象深刻的进步，但仍然存在重大挑战：（1）地面真相深度标签很难大规模收集，（2）通常认为相机信息是已知的，但通常是不可靠的，并且（3）限制性摄像机假设很常见，即使在实践中使用了各种各样的相机类型和镜头。在本论文中，我们专注于放松这些假设，并描述将相机变成真正通用深度传感器的最终目标的贡献。