关键词： STEAM   计算思维   项目式学习   机器人  

摘要： 目前,国内STEAM教育理念越来越受到人们的关注,计算思维培养也日趋低龄化。文章结合小学生认知规律、学习兴趣和学习需求,与团队成员从顶层设计出发,开展面向小学生计算思维的机器人项目式学习实践研究,依托多学科知识,发展小学生计算思维。研究采用项目式学习方式开展教学,以“精准防御抗击病毒”竞赛项目为例,从“进入情景、分析问题”“找出规律、抽象特征”“建立模型、设计算法”“运行程序、改进优化”“总结经验、迁移应用”等环节阐述了其在研究中的具体实施情况,旨在培养小学生运用计算思维界定分析问题、抽象建立问题模型、设计系统解决方案的能力,为发展小学生的计算思维提供了借鉴和参考。

关键词： 三自由度并联机器人   Delta机器人   动力学建模   凯恩方程  

摘要： Delta并联机器人被广泛用于小物品的高速拣选和包装等。为了得到优良的性能,控制系统设计和机械结构设计时需要考虑动力学模型的影响。文中利用凯恩方程对三自由度Delta并联机器人建立了动力学反解模型。文中建立的动力学模型结构紧凑。在整个建模过程中,只是用到了动平台的位置、速度、角速度参数和主动转动副转角、角速度及角加速度,不需要求出被动臂(即空间平行四边形机构)的位姿参数、(角)速度和(角)加速度。

关键词： Evolutionary robotics   Estimation-exploration algorithm   Neural network   Physics-based simulation   Information loss  

摘要： Theory of mind (ToM) is the ability to understand others' mental states (e.g., intentions). Studies on human ToM show that the way we understand others' mental states is very efficient, in the sense that observing only some portion of others' behaviors can lead to successful performance. Recently, ToM has gained interest in robotics to build robots that can engage in complex social interactions. Although it has been shown that robots can infer others' internal states, there has been limited focus on the data utilization of ToM mechanisms in robots. Here we show that robots can infer others' intentions based on limited information by selectively and flexibly using behavioral cues similar to humans. To test such data utilization, we impaired certain parts of an actor robot's behavioral information given to the observer, and compared the observer's performance under each impairment condition. We found that although the observer's performance was not perfect compared to when all information was available, it could infer the actor's mind to a degree if the goal-relevant information was intact. These results demonstrate that, similar to humans, robots can learn to infer others' mental states with limited information.

关键词： Group of rigid motions   Compactification   Robotics  

摘要： We introduce a compactification of the group of rigid motions in 3-space derived from the Study model for this group. We use this compactification in robot kinematics, by considering the boundary of the configuration space of a robot. We study in particular the degeneration of the direct kinematic problem for some parallel robots with three degrees of freedom. (C) 2020 Elsevier B.V. All rights reserved.

关键词： mobile robots   artificial potential fields   field lines of force   trajectory control  

摘要： In the well-known works devoted to the method of potential fields in mobile robotics, the key importance is attached to the mechanism of force influence on the movement of the robot;it determines the law of change in the velocity of its movement. In this article, a new methodology for using virtual fields is proposed: the force aspect is excluded and the lines of intensity of the created field set only the desired trajectories of the robot's movement, and following a given trajectory is carried out by a two-contour control system for the direction and velocity of the robot's movement. The question of constructing the attracting and repulsive potentials is discussed. The results of simulating the trajectory control of the two-wheeled robot are presented.

关键词： Chronic stroke   Dual-site transcranial direct current stimulation   Gait recovery   Robot-aided gait training  

摘要： Background Stroke is one of the main causes of impairment affecting daily activities and quality of life. There is a growing effort to potentiate the recovery of functional gait and to enable stroke patients to walk independently. Aim To estimate the effects of dual-site transcranial direct current stimulation (dstDCS) on gait recovery in chronic stroke patients provided with robot-aided gait training (RAGT). Methods Thirty-seven patients were included in this retrospective clinical study. Nine patients were provided with dstDCS during the first 10 min of RAGT by using Lokomat (R) Pro (on-RAGT), 15 patients immediately after RAGT (post-RAGT), and 13 patients immediately before RAGT (pre-RAGT). Results Each group improved over time concerning disability burden and lower limb strength. on-RAGT and post-RAGT experienced better improvement in balance (p < 0.001) and, moderately, gait endurance (p = 0.04) as compared to pre-RAGT. Furthermore, all treatments decreased the facilitation of the unaffected hemisphere (p < 0.001) and the inhibition of the affected hemisphere (p < 0.001). The duration of such aftereffects was found to be greater for post-RAGT. Discussion and conclusion This is the first trial with dstDCS coupled with RAGT in chronic stroke patients with gait impairment. When timely coupled with RAGT, dstDCS may be considered an effective tool for the recovery of lower limb function in patients with first unilateral stroke in the chronic phase. Moreover, our data suggest the ductility of dstDCS concerning RAGT timing, thus making this intervention suitable in a neurorehabilitation setting and well adaptable to patients' needs.

关键词： Dynamic task allocation   Communication topology   Swarm robotics  

摘要： Cooperation is a central idea to the usage of swarm robotics. It enables the solution of complex problems with a coordinated execution of simple tasks by a large group of small robot, which together lead to the achievement of the swarm common goal. This coordination is only possible with an efficient task allocation. Inspired by the strategy of the particle swarm optimization algorithm, we propose a novel algorithm called the Clustered Dynamic Task Allocation. This algorithm performs task allocation in a swarm robotic system in a fully distributed manner. It performs a guided search of the allocation space using the concept of adaptive speed. This search process requires information exchange between robots. This robot communication process must be planned carefully so as to achieve two conflicting objectives: the knowledge acquired by a given robot must flow throughout the swarm so that the optimization process may converge yet this communication must be limited so it does not hinder the efficiency of the task allocation process regarding large swarms. This paper proposes the use of a clustered communication topology between the swarm robots, aiming to optimize the underlying communication process, and thus enabling efficient task allocation for large robotic swarms. The results obtained with the cluster-based topology are compared to those obtained with the full mesh-based topology. On average, the results show a clear improvement in terms of execution time and battery charge requirements. Moreover, the performance of the proposed algorithm and the stability of the produced allocation are compared to other well-known models, demonstrating its better applicability to real-world swarm robotics based systems. (C) 2021 Elsevier B.V. All rights reserved.

关键词： Self-healing materials  

摘要： The intrinsic compliance of soft robots provides safety, a natural adaptation to its environment, allows to absorb shocks, and protects them against mechanical impacts. However, a literature study shows that the soft polymers used for their construction are susceptible to various types of damage, including fatigue, overloads, interfacial debonding, and cuts, tears and perforations by sharp objects. An economic and ecological solution is to construct future soft robotic systems out of self-healing polymers, incorporating the ability to heal damage. This review paper proposes criteria to evaluate the potential of a self-healing polymer to be used in soft robotic applications. Based on these soft robotics requirements and on defined performance parameters of the materials, linked to the mechanical and healing properties, the different types of self-healing polymers already available in literature are critically assessed and compared. In addition to a description of the state of the art on self-healing soft robotics, the paper discusses the driving forces and limitations to spur the interdisciplinary combination between self-healing polymer science and soft robotics.

关键词： Autism spectrum disorder   Robots   Education   Intervention   ICT  

摘要： During the last two decades, the use of Information and Communication Technologies (ICT) has opened new paths in the intervention of people with Autism Spectrum Disorder (ASD). These may include intervention based on "social robots". This research aims to review the state of scientific production on social robotics in the intervention of students with ASD during 2000-2019 to establish an action protocol in the use of this tool through a list of bibliometric indicators. To achieve this objective, we worked through the main collection of the Web of Science (WoS), obtaining a sample of 69 *** results indicate that the authors with the highest scientific production are American, even though they do not own the most cited articles in the field. In this sense, the great number of publications are indexed in the JCR Q1. Likewise, two journals are the work core of the field of study. Moreover, the vast majority of the studies are focused in different areas such as: communication and social interaction, repeated and stereotyped patterns of behaviour, interest, or activity. As a conclusion, robotics is a tool increasingly used by students with ASD. Moreover, robotics can be applied through a protocol based on the indicators analyzed. Therefore, future researchers in the field would use the indicators to determine, for example, which area to work in, which year they could obtain information or which journals publish the highest quality research. With the information provided by these indicators, a robotic intervention could be implemented.

关键词： Task analysis   Service robots   Collaboration   Resource management   Decision making   Symbiosis   Collaborative robots   fog computing   Industry 4   0   Internet of Things   robotic symbiotic network   task distribution  

摘要： Collaborative robots are an emerging area where robots share resources among each other for mutual benefit. They are particularly becoming popular in a modern industrial environment, primarily to improve production efficiency. This often involves some sort of decision making at the robots. Traditionally, the robots are connected to the cloud infrastructure and edge locations to offload compute-intensive tasks. But due to the dynamic workload generated and additional network delay, cloud, and edge locations are deemed unsuitable computing paradigms for use in industrial robots. In this article, we propose a symbiotic robotics framework where robots share their onboard computing capabilities for effective task offloading and its execution. Furthermore, the underlying symbiotic paradigm incorporates the concept of repute based on every successful task offloading and execution. The experimental results demonstrate a significant performance gain in terms of offloading time, task completion time, and overall efficiency when compared to two classical task offloading schemes.