关键词： Language arts   Education   Robotics  

摘要： Two areas in education that researchers continue to address are: (1) the search for best practices to support students who are language learners with academic success (Lesaux & Geva, 2006; Lesaux, Kieffer, Kelley, & Harris, 2014; Wilson, Fang, Rollins, & Valadez, 2016); and (2) the increased inclusion of STEM-related activities in educational settings (Barak & Zadok, 2009; Mitnik, Nussbaum, & Soto, 2008; Sullivan, 2008). The purpose of this qualitative, case study was to examine the use of robotics – a STEM-related activity – with connections to the literacy development of students identified as language learners during an eight-week, community-based robotics program. Additional attention was paid towards the students’ development and application of academic vocabulary within the program. The theoretical framework for this study was framed by Papert’s (1993) theory of constructionism and Long’s (1996) interaction hypothesis for language acquisition. The major findings from this study collapsed into the following themes: (1) informational texts; (2) writing; and (3) dialogue. Overall, findings from this study showed providing students with a specific task (i.e., constructing and programming a LEGO® MINDSTORMS® robot) promoted research, writing, and communication, in which the students encountered and used academic vocabulary. This study demonstrates the potential robotics has in supporting the literacy and academic vocabulary development of students who are language learners, and encourages the need for additional research on the use of robotics in educational settings and non-STEM-related fields.

关键词： Motivational system   extrinsic motivation   cognitive developmental robotics   goal identification  

摘要： Cognitive Developmental Robotics relies on lifelong open-ended learning processes, where mechanisms are needed to allow the robot to self-discover and self-select goals as well as to self-define its state space evaluation with regards to them. Thus, this paper addresses the problem of finding and using goals in continuous state spaces and automatically obtaining sub-goal hierarchies that allow autonomous development. In particular, the main purpose of this paper is to propose a new approach to the creation of utility models based on the concept of separable utility regions (SURs), which reduce the complexity of standard value function like utility models. These regions exhibit a correlation between the expected utility and the response of one sensor of the robot. Once they are discovered, the evaluation of the candidate states is only based on the changes of one sensor, which provides a strong independence from noise or dynamism in the utility models. A non-static variation of the classical collect-a-ball scenario and a robot gathering problem were used to test this approach in simulation and on real robots in order to identify goals and sub-goals in an autonomous way. The results confirm the good response of the method as a highly promising approach towards autonomous learning of continuous domains in cognitive robotics.

关键词： 工业机器人   机器人动力学   时间最优轨迹规划   轨迹优化   凸优化  

摘要： 随着工业生产线的自动化与智能化水平不断提高,工业机器人的轨迹规划能力也面临着更严格的要求。工业机器人的时间最优轨迹规划是提高生产效率的重要技术,在过去几十年中吸引了国内外众多研究人员的研究兴趣。如何使工业机器人的末端执行器,在最短的时间内沿着预定的笛卡尔空间路径运动,同时满足运动学约束与动力学约束,仍然是一个困难而重要的问题。因此本文以工业机器人的轨迹优化算法为研究对象,针对不同的约束条件与目标函数,规划出满足工业应用要求的最优轨迹。具体研究内容如下:首先,根据小型六轴机器人的改进DH参数进行运动学建模,分析正运动学并计算连杆间的齐次变换矩阵。为了避免采用代数解法进行过多的矩阵求逆运算,选择几何投影法与欧拉角解法相结合的方法,求解小型六轴机器人的逆运动学。分别利用牛顿欧拉迭代法与拉格朗日方程法对小型六轴机器人进行动力学建模,通过编写MATLAB程序验证动力学算法,并比较了两种动力学算法的计算效率与计算误差。其次,介绍了沿预定路径的工业机器人时间最优轨迹规划算法。该算法基于机器人的完整非线性动力学,利用路径参数化的方法,建立时间最优轨迹规划的数学模型。利用凸松弛法将粘性摩擦力引入的非凸约束转化为凸约束,并将非线性的目标函数和约束转化为二阶锥约束。制定适当的离散化方案,将轨迹优化问题转化为有限维度的二阶锥规划问题。编写时间最优轨迹规划算法的MATLAB程序,调用凸优化求解器SDPT3获得时间最优轨迹的数值解。再次,针对时间最优轨迹规划算法存在的缺点,通过原理分析、模型推导、程序实现等方法,对时间最优轨迹规划算法进行改进:施加更多满足实际需求的运动学约束;目标函数增加对能量消耗和总加加速度的限制,从而降低运行时间最优轨迹的能量消耗,限制关节加速度的突变,改善轨迹的跟踪性能;引入速度相关的转矩约束,进一步降低时间最优轨迹的运行时间。最后,为了验证时间最优轨迹的可实施性,搭建了小型六轴机器人的Simulink-ADAMS机电联合仿真平台,对轨迹优化算法生成的最优轨迹进行了仿真测试,再将仿真验证后的最优轨迹在小型六轴机器人实验平台上运行,验证算法的有效性与最优轨迹的可实施性。

关键词： 中国青少年   机器人竞赛  

摘要： 人工智能、机器人、编程……这些大热的词儿对于咱们的读者来说肯定早就不陌生了。因为这些知识已经进入了校园,被越来越多的同学所熟知,更加高级的运用也被一些同学熟练掌握。在这次机器人大赛中,猫哥看到不少同学年纪轻轻,俨然已经是机器人编程及操作的大佬,实在是让人佩服!

关键词： Human-robot interaction   co-verbal gesture   gestural annotation   word representation   robotic speech  

摘要： Human-Robot Interaction (HRI) is a growing area of interest in Artificial Intelligence that aims to make interaction with robots more natural. In this sense, numerous research studies on verbal and visual interactions with robots have appeared. The present paper will focus on non-verbal communication and, more specifically, gestures related to speech, which is an open question. With the aim of developing this part of Human-Robot Interaction or HRI, a new architecture is proposed for the assignment of gestures to speech based on the analysis of semantic similarities. In this way, gestures will be intelligently selected using Natural Language Processing (NLP) techniques. The conditions for gesture selection will be determined from an assessment of the effectiveness of different language models in a lexical substitution task applied to gesture annotation. On the basis of this analysis, the aim is to compare models based on expert knowledge and statistical models generated from lexical learning.

关键词： 机器人教学   机器人竞赛   教学模式   WER  

摘要： 随着我国科技和信息化水平的不断提高,人工智能、虚拟现实、智能机器人等新兴技术的出现,人工智能领域的机器人教育与机器人竞赛已经逐步走入人们的视野,成为培养和提高中学生创新能力的主要手段之一。目前我国许多地区的中小学已经将人工智能和机器人教育引入课堂教学,西部欠发达地区大部分中小学虽然也已经开始了机器人教育的相关推广活动,但由于师资力量、教学资源相对缺乏和薄弱,面向全校开展相关课程还存在困难。因此,在教学资源条件较弱的情况下,如何通过组织建立兴趣小组,机器人社团,让感兴趣的学生参与机器人竞赛等相关活动,使其更好地掌握机器人方面的知识与技能,进而达到以点带面、开拓学生眼界和思维的目的,提升学生创新能力的作用,是当前机器人教育者亟待解决的问题。本文以机器人竞赛为前提,机器人教学方法为落脚点,探究不同情境下对学生的培养模式。主要研究内容如下:(1)通过阅读大量文献资料,针对西部某中学高一年级学生进行了综合素质相关的调查,分析了学生的学习目的、学习风格及综合素质培养方面的欠缺。并通过对相关个别学生的访谈,总结出机器人竞赛对学生的积极影响,目前竞赛培训的现状及存在的问题。(2)针对目前机器人竞赛培训中的不足,提出机器人竞赛培训模式设计的需求,针对应试教育中缺少对学生的创造性培养的问题,构建出机器人竞赛培训模式的具体内容,实施方法及评价体系。(3)针对市面上缺少WER机器人竞赛的培训教材的问题,列出培训手册的大纲及主要内容,以期为机器人教师提供理论参考,为零基础的学生提供指导建议。结合“发射卫星”任务做出具体案例的设计、实践与分析并提出对教师的12条切实可行的建议。

关键词： 超冗余混联机器人   脊线模态法   运动学   轨迹规划   刚体逆动力学  

摘要： 超冗余混联机器人具有较高的负载能力、较强的避障能力以及较好的灵活性，对复杂的非结构化环境具有较好的适应性、相容性及容错性，使其具有较为广泛的应用前景。本文根据超冗余混联机器人的研发需求，对其运动学、刚体逆动力学以及轨迹规划等方面进行研究，论文的主要工作和取得的研究成果如下：　　1.通过分析超冗余混联机器人的结构方案进而研究其位置逆解。在给定末端位姿下，可采用一条平滑连续的空间曲线来穿过各个平台的中心来表征机器人的整体特征，通过引入“脊线模态法”构造出一条模态脊线，利用二分法进行平台中心位置搜索，并以并联组成模块中间支链长度约束、动平台最大转角、外围支链上球铰链最大转角及并联组成模块外支链上虎克铰的转角等作为约束条件，从而得出超冗余混联机器人的位置逆解。　　2.对超冗余混联机器人的运动学进行分析。通过闭环矢量法构造出超冗余混联机器人并联组成模块的运动学方程，根据超冗余混联机器人“累加”的特性推导出各个平台在基座标系下的运动学关系式，并给出了速度级逆运动学的表达式。　　3.对超冗余混联机器人的关节空间轨迹规划进行了研究。在关节空间内，通过对并联组成模块动平台的转动进行解耦，并运用多项式对欧拉转角进行插补，从而实现超冗余混联机器人平稳的运动。　　4.对超冗余混联机器人的刚体逆动力学进行了研究。通过推导出超冗余混联机器人任务空间与关节空间的运动学映射关系，在此基础上进一步推导得到各个部件质心的运动关系，通过虚功原理建立出支链驱动力理论模型，最后通过数值算例进行仿真验证。　　5.为验证理论推导运动学模型和动力学模型的正确性，建立超冗余混联机器人的虚拟样机模型并进行仿真。结果表明：超冗余混联机器人的理论推导运动学和动力学模型与ADAMS?仿真结果保持一致，验证了理论推导的正确性。

关键词： 可控机构   焊接机器人   运动副间隙   运动学   动力学   机器人控制  

摘要： 可控机构综合了闭环机构和开链机构的优点,运行速度高、承载能力强、控制简单且具有一定的柔性,很好地适应现代机械工业的发展需要。将“多自由度可控机构”应用到机器人机构领域,在振动大小、残余振动时间、工作速度、工作效率等方面都相对现行串联式机器人具有优势。然而,在使用过程中该类机器人有时会出现一种较大的异常振动,严重影响了其正常工作。因此,迫切需要对这类多自由度可控机构机构式机器人动态性能进行全面、深入的研究,发现这种异常振动的原因。而运动副间隙是影响机械系统平稳、高效、准确运行的一个关键因素。因此深入研究运动副间隙对可控机构式机器人动态性能的影响有一定的理论意义和实际工程价值。本文以一种可控机构式焊接机器人为研究对象,系统地对不考虑和考虑间隙状态下的机器人运动学和动力学进行了分析,并采用一定的控制方法,对间隙导致的末端位移误差进行了补偿。本文主要工作有以下几个方面:分析了可控机构式焊接机器人构型,利用D-H法则建立了其运动学模型,在此基础上,采用连续接触间隙副模型,并对该模型下考虑间隙机器人的运动学进行了分析,并与理想焊接机器人对比,得到考虑间隙状态下的机器人末端位置误差。采用三状态间隙模型,建立了考虑间隙的转动副模型,对不考虑和考虑间隙的可控机构式焊接机器人进行了动力学建模。对不考虑和考虑间隙状态下的机器人进行了动力学仿真和对比分析。分析了不同间隙大小、不同驱动速度、不同运动副材料下的考虑间隙的机器人动态响应,为该机器人装配精度选择,运动副材料选择,和工作速度范围选取提供一定的理论参考。建立了存在间隙非线性环节的机器人关节控制系统,采用粒子群优化算法对控制系统进行了参数识别。对机器人控制系统进行了仿真分析。结果表明,采用一定的控制方法,可以有效降低考虑间隙的可控机构式焊接机器人末端位移误差,提高机器人运行精度。

关键词： Robotics   engineering design process   middle school   meaningful learning   Revised Bloom Taxonomy   representational model  

摘要： This paper describes a study of students' meaningful learning of the engineering design process during their participation in robotics activities. The population consisted of middle-school students (ages 13-15 years) who participated in the FIRST (R) LEGO (R) League competition. The methodology used was qualitative, including observations and interviews. The analysis was based on the Revised Bloom Taxonomy. Almost all the groups demonstrated meaningful learning, although some reached higher levels than others. Most of the groups demonstrated the understanding/applying level during each of the design process phases (searching and decision making, construction and testing, diagnosing and debugging), some demonstrated the analyzing/evaluating level, but only a few demonstrated the higher level of creating. Factors that seemed to play a role in the students' learning include: (a) the teaching or mentoring style;(b) the absence of a robotics textbook;(c) the extra-curricular competition-oriented nature of the activities;and (d) the unstable nature of the design of the robot.

摘要： This research focuses on proving the presence of coloured noise on the longitudinal, lateral and rotational velocity in steady-state cornering of a skid steer mobile robot. Furthermore, it also focuses on the creation of a Gaussian filter which is able to recreate the characteristics of the measured coloured noise. This is done to determine the characteristics of the Gaussian filter based on real-life experimental values, which defines the Gaussian filter that creates coloured process noise in the Active Inference algorithm. To accomplish the main research goal, the following is done: - Create a linear dynamical model of the jackal robot and optimize the model in such a way that its velocity states resemble the experimental values of the velocities for the given experimental inputs. - Show the presence of coloured noise in the dynamical behaviour of the jackal robot. - Create a Gaussian filter and determine its characteristics, which can recreate the coloured noise found in the velocity states of the jackal robot in steady state turning. To accomplish this, experiments are done capturing the linear acceleration, rotational ve- locities, position and heading of the skid steer mobile robot using both the internal sensors of the robot as well as an external motion capturing system. A linear model of the jackal robot is constructed and discretised as the noise is a function of the difference between the experimental value for the next step state [k + 1]exp and the prediction of the next step state [k + 1]est. The prediction is made by inputting the experimental values for step [k] into the discretised linear model together with the model input. The difference between [k + 1]exp and [k+1]est is the noise on the velocities during the steady-state cornering experiments. Optimal values for Gaussian filter are found by fitting the autocorrelations of coloured noise which is made by filtering white noise with a range of Gaussian filters on the autocorrelation of the measured