Synthesizing high-fidelity videos from real-world multi-view input is challenging because of the complexities of real-world environments and highly dynamic motions. Previous works based on neural radiance fields have demonstrated high-quality reconstructions of dynamic scenes. However, training such models on real-world scenes is time-consuming, usually taking days or weeks. In this paper, we present a novel method named MixVoxels to better represent the dynamic scenes with fast training speed and competitive rendering qualities. The proposed MixVoxels represents the 4D dynamic scenes as a mixture of static and dynamic voxels and processes them with different networks. In this way, the computation of the required modalities for static voxels can be processed by a lightweight model, which essentially reduces the amount of computation, especially for many daily dynamic scenes dominated by the static background. To separate the two kinds of voxels, we propose a novel variation field to estimate the temporal variance of each voxel. For the dynamic voxels, we design an inner-product time query method to efficiently query multiple time steps, which is essential to recover the high-dynamic motions. As a result, with 15 minutes of training for dynamic scenes with inputs of 300-frame videos, MixVoxels achieves better PSNR than previous methods. Codes and trained models are available at https://github.com/fengres/mixvoxels
translated by 谷歌翻译
This paper introduces a structure-deformable land-air robot which possesses both excellent ground driving and flying ability, with smooth switching mechanism between two modes. The elaborate coupled dynamics model of the proposed robot is established, including rotors, chassis, especially the deformable structures. Furthermore, taking fusion locomotion and complex near-ground situations into consideration, a model based controller is designed for landing and mode switching under various harsh conditions, in which we realise the cooperation between fused two motion modes. The entire system is implemented in ADAMS/Simulink simulation and in practical. We conduct experiments under various complex scenarios. The results show our robot can accomplish land-air switching swiftly and smoothly, and the designed controller can effectively improve the landing flexibility and reliability.
translated by 谷歌翻译
3D多对象跟踪(MOT)确保在连续动态检测过程中保持一致性,有利于自动驾驶中随后的运动计划和导航任务。但是,基于摄像头的方法在闭塞情况下受到影响,准确跟踪基于激光雷达的方法的对象的不规则运动可能是具有挑战性的。某些融合方法效果很好,但不认为在遮挡下出现外观特征的不可信问题。同时,错误检测问题也显着影响跟踪。因此,我们根据组合的外观运动优化(Camo-Mot)提出了一种新颖的相机融合3D MOT框架,该框架使用相机和激光镜数据,并大大减少了由遮挡和错误检测引起的跟踪故障。对于遮挡问题,我们是第一个提出遮挡头来有效地选择最佳对象外观的人,从而减少了闭塞的影响。为了减少错误检测在跟踪中的影响,我们根据置信得分设计一个运动成本矩阵,从而提高了3D空间中的定位和对象预测准确性。由于现有的多目标跟踪方法仅考虑一个类别,因此我们还建议建立多类损失,以在多类别场景中实现多目标跟踪。在Kitti和Nuscenes跟踪基准测试上进行了一系列验证实验。我们提出的方法在KITTI测试数据集上的所有多模式MOT方法中实现了最先进的性能和最低的身份开关(IDS)值(CAR为23,行人为137)。并且我们提出的方法在Nuscenes测试数据集上以75.3%的AMOTA进行了所有算法中的最新性能。
translated by 谷歌翻译
两栖地面汽车将飞行和驾驶模式融合在一起,以实现更灵活的空中行动能力,并且最近受到了越来越多的关注。通过分析现有的两栖车辆,我们强调了在复杂的三维城市运输系统中有效使用两栖车辆的自动驾驶功能。我们审查并总结了现有两栖车辆设计中智能飞行驾驶的关键促成技术,确定主要的技术障碍,并提出潜在的解决方案,以实现未来的研究和创新。本文旨在作为研究和开发智能两栖车辆的指南,以实现未来的城市运输。
translated by 谷歌翻译
机器人社区早已期望在混乱环境中处理物体的能力。但是,大多数作品只是专注于操纵,而不是在混乱的对象中呈现隐藏的语义信息。在这项工作中,我们介绍了在混乱的场景中进行体现探索的场景图,以解决此问题。为了在混乱的情况下验证我们的方法,我们采用操纵问题答案(MQA)任务作为我们的测试基准,该测试基准要求具有体现的机器人具有主动探索能力和视觉和语言的语义理解能力。任务,我们提出了一种模仿学习方法,以生成探索的操作。同时,采用了基于动态场景图的VQA模型来理解操纵器手腕摄像头的一系列RGB帧以及操纵的每一步,以在我们的框架中回答问题。我们提出的框架对于MQA任务有效,代表了混乱的场景中的任务。
translated by 谷歌翻译
我们通过以端到端的方式对大规模未标记的数据集进行分类,呈现扭曲,简单和理论上可解释的自我监督的表示学习方法。我们使用Softmax操作终止的暹罗网络,以产生两个增强图像的双类分布。没有监督,我们强制执行不同增强的班级分布。但是,只需最小化增强之间的分歧将导致折叠解决方案,即,输出所有图像的相同类概率分布。在这种情况下,留下有关输入图像的信息。为了解决这个问题,我们建议最大化输入和课程预测之间的互信息。具体地,我们最小化每个样品的分布的熵,使每个样品的课程预测是对每个样品自信的预测,并最大化平均分布的熵,以使不同样品的预测变得不同。以这种方式,扭曲可以自然地避免没有特定设计的折叠解决方案,例如非对称网络,停止梯度操作或动量编码器。因此,扭曲优于各种任务的最先进的方法。特别是,在半监督学习中,扭曲令人惊讶地表现出令人惊讶的是,使用Reset-50作为骨干的1%ImageNet标签实现61.2%的顶级精度,以前的最佳结果为6.2%。代码和预先训练的模型是给出的:https://github.com/byteDance/twist
translated by 谷歌翻译
预测未来的人类运动在各种现实生活中的人机相互作用中起着重要作用。统一的制定和多阶建模是用于分析和代表人类运动的两个批判性观点。与事先作品相比,通过构建深度状态空间模型(Deepssm),我们提高人类运动系统的多阶建模能力,以实现更准确的预测。 DeepsSM利用状态空间理论和深网络的优点。具体地,我们通过状态空间理论将人体运动系统作为动态系统的状态空间模型和模型运动系统,为不同的人类运动系统提供统一的配方。此外,新颖的深度网络旨在参数化该系统,该系统共同模拟状态转换和状态观测转换过程。以这种方式,系统的状态由时变人运动序列的多阶信息更新。通过状态观察转换递归预测多个未来的姿势。为了进一步提高系统的模型能力,引入了一种新颖的损失,WT-MPJPE(每个关节位置误差的加权时间平均值),以优化模型。拟议的损失鼓励该系统通过增加重量来实现更准确的预测到早期时间步骤。两个基准数据集(即,Human3.6M和3DPW)的实验证实,我们的方法实现了最先进的性能,每个关节的精度至少为2.2mm。代码将可用:\ url {https:/github.com/lily2lab/deepssm.git}。
translated by 谷歌翻译
Recently, the self-supervised pre-training paradigm has shown great potential in leveraging large-scale unlabeled data to improve downstream task performance. However, increasing the scale of unlabeled pre-training data in real-world scenarios requires prohibitive computational costs and faces the challenge of uncurated samples. To address these issues, we build a task-specific self-supervised pre-training framework from a data selection perspective based on a simple hypothesis that pre-training on the unlabeled samples with similar distribution to the target task can bring substantial performance gains. Buttressed by the hypothesis, we propose the first yet novel framework for Scalable and Efficient visual Pre-Training (SEPT) by introducing a retrieval pipeline for data selection. SEPT first leverage a self-supervised pre-trained model to extract the features of the entire unlabeled dataset for retrieval pipeline initialization. Then, for a specific target task, SEPT retrievals the most similar samples from the unlabeled dataset based on feature similarity for each target instance for pre-training. Finally, SEPT pre-trains the target model with the selected unlabeled samples in a self-supervised manner for target data finetuning. By decoupling the scale of pre-training and available upstream data for a target task, SEPT achieves high scalability of the upstream dataset and high efficiency of pre-training, resulting in high model architecture flexibility. Results on various downstream tasks demonstrate that SEPT can achieve competitive or even better performance compared with ImageNet pre-training while reducing the size of training samples by one magnitude without resorting to any extra annotations.
translated by 谷歌翻译
In this paper, we propose a robust 3D detector, named Cross Modal Transformer (CMT), for end-to-end 3D multi-modal detection. Without explicit view transformation, CMT takes the image and point clouds tokens as inputs and directly outputs accurate 3D bounding boxes. The spatial alignment of multi-modal tokens is performed implicitly, by encoding the 3D points into multi-modal features. The core design of CMT is quite simple while its performance is impressive. CMT obtains 73.0% NDS on nuScenes benchmark. Moreover, CMT has a strong robustness even if the LiDAR is missing. Code will be released at https://github.com/junjie18/CMT.
translated by 谷歌翻译
Dataset distillation has emerged as a prominent technique to improve data efficiency when training machine learning models. It encapsulates the knowledge from a large dataset into a smaller synthetic dataset. A model trained on this smaller distilled dataset can attain comparable performance to a model trained on the original training dataset. However, the existing dataset distillation techniques mainly aim at achieving the best trade-off between resource usage efficiency and model utility. The security risks stemming from them have not been explored. This study performs the first backdoor attack against the models trained on the data distilled by dataset distillation models in the image domain. Concretely, we inject triggers into the synthetic data during the distillation procedure rather than during the model training stage, where all previous attacks are performed. We propose two types of backdoor attacks, namely NAIVEATTACK and DOORPING. NAIVEATTACK simply adds triggers to the raw data at the initial distillation phase, while DOORPING iteratively updates the triggers during the entire distillation procedure. We conduct extensive evaluations on multiple datasets, architectures, and dataset distillation techniques. Empirical evaluation shows that NAIVEATTACK achieves decent attack success rate (ASR) scores in some cases, while DOORPING reaches higher ASR scores (close to 1.0) in all cases. Furthermore, we conduct a comprehensive ablation study to analyze the factors that may affect the attack performance. Finally, we evaluate multiple defense mechanisms against our backdoor attacks and show that our attacks can practically circumvent these defense mechanisms.
translated by 谷歌翻译