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31.
32.
Rianne van den Berghe Mirjam de Haas Ora Oudgenoeg-Paz Emiel Krahmer Josje Verhagen Paul Vogt Bram Willemsen Jan de Wit Paul Leseman 《Journal of Computer Assisted Learning》2021,37(2):396-410
This study investigates the degree to which children anthropomorphize a robot tutor and whether this anthropomorphism relates to their vocabulary learning in a second-language (L2) tutoring intervention. With this aim, an anthropomorphism questionnaire was administered to 5-year-old children (N = 104) twice: prior to and following a seven-session L2 vocabulary training with a humanoid robot. On average, children tended to anthropomorphize the robot prior to and after the lessons to a similar degree, but many children changed their attributed anthropomorphic features. Boys anthropomorphized the robot less after the lessons than girls. Moreover, there was a weak but significant positive correlation between anthropomorphism as measured before the lessons and scores on a word-knowledge post-test administered the day after the last lesson. There was also a weak but significant positive correlation between the change in anthropomorphism over time and scores on a word-knowledge post-test administered approximately 2 weeks after the last lesson. Our results underscore the need to manage children's expectations in robot-assisted education. Also, future research could explore adaptations to individual children's expectations in child-robot interactions. 相似文献
33.
Lian Chen Qing Wang 《International Journal of Adaptive Control and Signal Processing》2021,35(12):2372-2388
This article presents an extended-state-observer-based dynamic surface control approach for flexible-joint robot systems with asymmetric input saturation and large unknown dynamic knowledge. Traditional controllers for flexible-joint robot systems usually use approximation technology to deal with unknown dynamics knowledge. Unlike the traditional control algorithm, this article utilizes an extended state observer to estimate the unknown dynamics. For the closed-loop system, the delay strategy handles the time-scale separation issue, the filtering system overcomes the “explosion of differentiation” caused by the repeated differentiation of auxiliary control signals, and the mean-value-theorem solves the input saturation problem of the actuator. The stability analysis implies that estimation errors of extended state observers (ESOs) and other state variables are semiglobally uniformly ultimately bounded. Compared with fuzzy control algorithms, the novel ESO-based dynamic surface control approach not only omits online learning time but also uses only a few control parameters to obtain satisfactory tracking performance. Finally, a comparison simulation experiment is provided to illustrate the effectiveness of the gained conclusions. 相似文献
34.
Mahmoud Elsisi 《国际智能系统杂志》2020,35(11):1857-1878
The controller design for the robotic manipulator faces different challenges such as the system's nonlinearities and the uncertainties of the parameters. Furthermore, the tracking of different linear and nonlinear trajectories represents a vital role by the manipulator. This paper suggests an optimal design for the nonlinear model predictive control (NLMPC) based on a new improved intelligent technique and it is named modified multitracker optimization algorithm (MMTOA). The proposed modification of the MTOA is carried out based on opposition-based learning (OBL) and quasi OBL approaches. This modification improves the exploration behavior of the MTOA to prevent it from becoming trapped in a local optimum. The proposed method is applied on the robotic manipulator to track different linear and nonlinear trajectories. The NLMPC parameters are tuned by the MMTOA rather than the trial and error method of the designer. The proposed NLMPC based on MMTOA is compared with the original MTOA, genetic algorithm, and cuckoo search algorithm in literature. The superiority and effectiveness of the proposed controller are confirmed to track different linear and nonlinear trajectories. Furthermore, the robustness of the proposed method is emphasized against the uncertainties of the parameters. 相似文献
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36.
针对高速公路高峰期拥挤产生的垃圾等问题,设计一种轨道式垃圾回收机器人,由光伏发电装置、机器人壳体、末端手爪、关节臂以及控制系统等组成,主体结构采用双臂三关节结构,采用西门子PLC控制系统,通过控制关节臂的旋转以及偏转、末端手爪的旋转及开合等动作来实现工作的目的。结合外场作业的特殊性,采用光伏能源装置,对其结构及控制系统进行设计,通过对机器人进行三维建模、运动和控制仿真分析,验证系统的可行性及有效性。 相似文献
37.
为提高工业机器人的柔性化及智能化水平,同时满足数据的实时共享、监控,使控制系统具有可扩展性与可移植性,设计了一种基于x86平台和RSI的工业机器人开放式控制系统。引入RSI后可载入应用程序包,实现PC工控机与KUKA机器人系统的实时性数据交换。运用模块化设计思路,针对硬件系统,制定软件系统平台的各功能模块,配合Windows操作系统的数据处理能力,在保证工业机器人实时性的前提下,实现了功能的扩展性和增减性。该系统在KUKA工业机器人力反馈实验平台上进行了可行性验证,试验表明,此开放式控制系统的实时响应性良好,满足预期控制要求。 相似文献
38.
摇床受处理量、给矿浓细度等条件变化影响,床面各条矿带的颜色、位置、宽度时常改变,需要人工及时调整接矿板的位置以达到合格的精矿品位,工人劳动强度大。为了实现摇床作业的自动巡检和操作,通过计算机视觉技术采集摇床矿带照片,研究了矿带图像识别算法,并在此基础上开发了摇床智能巡检机器人。工业试验表明,摇床智能巡检机器人实现了对一组多张摇床矿带的自动采图,图像识别算法实现了对矿带宽度、边界和颜色特征的数字化识别解析,实现了自动调节接矿板至目标位置,达到了替代人工、提升选矿指标的目的。 相似文献
39.
以三平动冗余驱动并联机床为研究对象,设计了一种具有位移放大功能的磁流变阻尼器,通过Ansys workbench有限元分析软件,对阻尼器的磁路饱和情况进行模拟仿真和分析,使阻尼器的阻尼出力达到最优。研究结果表明,通过优化使磁场分布更加合理,提高了阻尼器的力学性能,优化方法是可行有效的。 相似文献
40.
The parallel spindle heads with high rotational capability are demanded in the area of multi-axis machine tools and 3D printers. This paper focuses on designing a class of 2R1T (R: Rotation; T: Translation) parallel spindle heads and the corresponding collaborative 5-axis manipulators with 2-dimension (2D) large rotational angles. In order to construct 2D rotational degrees of freedom (DOFs), a platform with 2D revolute joints is proposed first. Based on the constraint screw theory, the feasible limbs that can be connected in the platform are synthesized. In order to provide constant rotational axis for the platform, a class of redundant limbs are designed. A class of redundant 2R1T parallel spindle heads is obtained by connecting the redundant limbs with the platform and the redundant characteristics are verified by the modified Grübler-Kutzbach criterion. The corresponding 5-axis collaborative manipulators are presented by constructing a 2-DOF series translational bottom moving platform. The inverse kinematics and the orientation workspace as well as the decoupling characteristics of this type of 2R1T parallel spindle heads are analyzed. The results show that these manipulators have large 2D rotational angles than the traditional A3/Z3 heads and can be potentially used in the application of multi-axis machine tools and the 3D printers. 相似文献