这项工作报告了开发针对腿部机器人地形遍历性建模的深层增强学习方法，该方法既包含了外部感受和本体感受性的感觉数据。现有作品使用机器人不合时宜的外部感受的环境特征或手工制作的运动功能；取而代之的是，我们建议还从本体感受的感官数据中学习机器人特异性惯性特征，以在单个深层神经网络中奖励近似。合并惯性功能可以改善模型保真度，并提供取决于在部署过程中机器人状态的奖励。我们使用最大熵深的逆增强学习（Medirl）算法训练奖励网络，并同时提出最大程度地减少轨迹排名损失，以应对腿部机器人示范的次优。所证明的轨迹通过运动能源消耗来排名，以学习能源感知的奖励功能和比示范更节能的政策。我们使用MIT Mini-Cheetah机器人和Mini-Cheetah模拟器收集的数据集评估我们的方法。该代码可在https://github.com/ganlumomo/minicheetah-traversability-irl上公开获得。

目标是在杂乱或Textuleless环境，相机（和多传感器）校准任务中的对象跟踪等问题，以及同时本地化和映射（SLAM）。用于这些任务的目标形状通常是对称的（方形，矩形或圆形），并且适用于结构化的密集传感器数据（例如像素阵列（即，图像）。然而，当使用稀疏传感器数据（例如LIDAR点云）并且遭受LIDAR的量化不确定性时，对称形状导致占用歧义。本文介绍了优化目标形状的概念，以消除LIDAR点云的姿势模糊性。目标被设计成在旋转和平移下的边缘点处引起大梯度，而相对于LIDAR以改善与点云稀疏相关的量化不确定性。此外，考虑到目标形状，我们提出了一种利用目标的几何形状来估计目标顶点的手段，同时全局估计姿势。模拟和实验结果（通过运动捕获系统验证）确认，通过使用最佳形状和全球求解器，即使在部分照明的目标放置30米处，我们也可以在翻译中的厘米误差和几度旋转。所有实现和数据集都可以在https://github.com/umich-bipedlab/optimal_shape_global_pose_estimation中获得。

我们提出并通过实验证明了双层机器人的反应性规划系统，在未开发，具有挑战性的地形上。该系统由低频规划线（5Hz）组成，用于找到渐近最佳路径和高频无功螺纹（300Hz）以适应机器人偏差。规划线程包括：多层本地地图，以计算地形上机器人的拖拉性;任何时间的全向控制Lyapunov函数（CLF），用于快速探索随机树星（RRT *），它会生成一个矢量字段，用于指定节点之间的运动;当最终目标位于当前地图之外时，子目标查找器;和一个有限状态的机器来处理高级任务决策。该系统还包括反应线，以避免在执行路径后用传统的RRT *算法出现的非平滑运动。具有机器人偏差的反应线应对，同时通过矢量字段（由闭环反馈策略定义）消除非平滑运动，其为机器人的步态控制器提供实时控制命令作为瞬时机器人姿势的函数。该系统在Cassie Blue的模拟和实验中进行了各种具有挑战性的户外地形和杂乱的室内场景，这是一个具有20个自由度的双模型机器人。所有实现在C ++中编码了机器人操作系统（ROS），可在https://github.com/umich-bipedlab/clf_reactive_planning_system中获得。

Safety critical systems involve the tight coupling between potentially conflicting control objectives and safety constraints. As a means of creating a formal framework for controlling systems of this form, and with a view toward automotive applications, this paper develops a methodology that allows safety conditions-expressed as control barrier functionsto be unified with performance objectives-expressed as control Lyapunov functions-in the context of real-time optimizationbased controllers. Safety conditions are specified in terms of forward invariance of a set, and are verified via two novel generalizations of barrier functions; in each case, the existence of a barrier function satisfying Lyapunov-like conditions implies forward invariance of the set, and the relationship between these two classes of barrier functions is characterized. In addition, each of these formulations yields a notion of control barrier function (CBF), providing inequality constraints in the control input that, when satisfied, again imply forward invariance of the set. Through these constructions, CBFs can naturally be unified with control Lyapunov functions (CLFs) in the context of a quadratic program (QP); this allows for the achievement of control objectives (represented by CLFs) subject to conditions on the admissible states of the system (represented by CBFs). The mediation of safety and performance through a QP is demonstrated on adaptive cruise control and lane keeping, two automotive control problems that present both safety and performance considerations coupled with actuator bounds.

接受高等教育对于少数族裔和新兴双语学生至关重要。但是，高等教育机构用来与准学生交流的语言通常太复杂了。具体而言，美国的许多机构发布录取申请指令远远高于典型高中毕业生的平均阅读水平，通常接近13年级或14年级。这导致学生之间不必要的障碍和获得高等教育。这项工作旨在通过简化文本来应对这一挑战。我们介绍PSAT（专业简化的录取文本），这是一个数据集，其中有112条从美国的高等教育机构中随机选择的录取说明。然后，这些文本将被专业地简化，并被各个机构招生办公室的专职员工专家进行了验证和接受。此外，PSAT带有1,883个原始简化句子对的手动对齐。结果是在与现有简化资源不同的高风险流派中评估和微调文本简化系统的首个语料库。

本文为两足机器人提供了一个步态控制器，鉴于局部斜率和摩擦锥信息，可以在各个地形上行走高度敏捷。没有这些考虑，不合时宜的影响会导致机器人绊倒，而在姿势脚下的切向反作用力不足会导致滑倒。我们通过以新颖的方式将基于角动量线性倒置的摆（ALIP）和模型预测控制（MPC）脚放置计划者组合来解决这些挑战，该模型由虚拟约束方法执行。该过程始于从Cassie 3D Bipedal机器人的完整动力学中抽象，该机器人的质量动力学中心的精确低维表示，通过角动量参数化。在分段平面地形假设和消除机器人质量中心的角动量的术语中，有关接触点的质心动力学变为线性，并具有四个尺寸。重要的是，我们在MPC公式中以均匀间隔的间隔内包含步骤的动力学，以便可以从逐步到步进机器人的演变上进行现实的工作空间约束。低维MPC控制器的输出通过虚拟约束方法直接在高维Cassie机器人上实现。在实验中，我们验证了机器人控制策略在各种表面上具有不同倾斜和质地的性能。

Making histopathology image classifiers robust to a wide range of real-world variability is a challenging task. Here, we describe a candidate deep learning solution for the Mitosis Domain Generalization Challenge 2022 (MIDOG) to address the problem of generalization for mitosis detection in images of hematoxylin-eosin-stained histology slides under high variability (scanner, tissue type and species variability). Our approach consists in training a rotation-invariant deep learning model using aggressive data augmentation with a training set enriched with hard negative examples and automatically selected negative examples from the unlabeled part of the challenge dataset. To optimize the performance of our models, we investigated a hard negative mining regime search procedure that lead us to train our best model using a subset of image patches representing 19.6% of our training partition of the challenge dataset. Our candidate model ensemble achieved a F1-score of .697 on the final test set after automated evaluation on the challenge platform, achieving the third best overall score in the MIDOG 2022 Challenge.

Supervised Question Answering systems (QA systems) rely on domain-specific human-labeled data for training. Unsupervised QA systems generate their own question-answer training pairs, typically using secondary knowledge sources to achieve this outcome. Our approach (called PIE-QG) uses Open Information Extraction (OpenIE) to generate synthetic training questions from paraphrased passages and uses the question-answer pairs as training data for a language model for a state-of-the-art QA system based on BERT. Triples in the form of <subject, predicate, object> are extracted from each passage, and questions are formed with subjects (or objects) and predicates while objects (or subjects) are considered as answers. Experimenting on five extractive QA datasets demonstrates that our technique achieves on-par performance with existing state-of-the-art QA systems with the benefit of being trained on an order of magnitude fewer documents and without any recourse to external reference data sources.

While the capabilities of autonomous systems have been steadily improving in recent years, these systems still struggle to rapidly explore previously unknown environments without the aid of GPS-assisted navigation. The DARPA Subterranean (SubT) Challenge aimed to fast track the development of autonomous exploration systems by evaluating their performance in real-world underground search-and-rescue scenarios. Subterranean environments present a plethora of challenges for robotic systems, such as limited communications, complex topology, visually-degraded sensing, and harsh terrain. The presented solution enables long-term autonomy with minimal human supervision by combining a powerful and independent single-agent autonomy stack, with higher level mission management operating over a flexible mesh network. The autonomy suite deployed on quadruped and wheeled robots was fully independent, freeing the human supervision to loosely supervise the mission and make high-impact strategic decisions. We also discuss lessons learned from fielding our system at the SubT Final Event, relating to vehicle versatility, system adaptability, and re-configurable communications.

While the brain connectivity network can inform the understanding and diagnosis of developmental dyslexia, its cause-effect relationships have not yet enough been examined. Employing electroencephalography signals and band-limited white noise stimulus at 4.8 Hz (prosodic-syllabic frequency), we measure the phase Granger causalities among channels to identify differences between dyslexic learners and controls, thereby proposing a method to calculate directional connectivity. As causal relationships run in both directions, we explore three scenarios, namely channels' activity as sources, as sinks, and in total. Our proposed method can be used for both classification and exploratory analysis. In all scenarios, we find confirmation of the established right-lateralized Theta sampling network anomaly, in line with the temporal sampling framework's assumption of oscillatory differences in the Theta and Gamma bands. Further, we show that this anomaly primarily occurs in the causal relationships of channels acting as sinks, where it is significantly more pronounced than when only total activity is observed. In the sink scenario, our classifier obtains 0.84 and 0.88 accuracy and 0.87 and 0.93 AUC for the Theta and Gamma bands, respectively.