关键词： 点焊机器人   动力学分析   ADAMS软件  

摘要： 如何确立电机和减速器的型号及各轴的运动参数,是机器人设计过程中非常重要的一个技术环节。以点焊机器人为例,主要通过ADAMS软件对机器人进行前处理、动力学分析及后处理,从而获得机器人各轴的运动技术参数,为电机和减速器的选择提供了理论依据。

关键词： 草方格   割断机构   动力学分析   ADAMS  

摘要： 横向割断机构是草方格铺设机器人横向铺设系统中一个重要的组成部分,直接影响机器人的正常运行。针对草方格铺设机器人所要完成的任务,设计出一套既适合工作环境、又能完成割断任务的新型机构。应用计算机仿真技术,利用Pro/ENGINEER软件绘制出割断机构的三维模型,观察模型设计是否存在干涉等现象;利用ADAMS软件对割断机构进行动力学仿真,通过仿真观察机构的运行,绘制出关键部位的速度、位移等参数曲线,在理论上确保割断机构动作方面的可行性、合理性;最后通过实验验证横向割断机构能够按设计完成割断草帘绳的任务。

关键词： 冗余度机器人   动力学   容错  

摘要： 提出了最小关节力矩突变指标,对冗余度机器人动力学容错性能进行了研究,通过构造关节力矩突变的表达式,在不同锁定时刻规划出各个关节力矩,并将规划结果与运动学关节速度突变规划出的关节力矩相比较,证明了在低速运动下可以用最小关节速度突变算法控制机器人的末端误差,而在高速运动下需要使用最小关节力矩突变算法控制机器人的末端误差.最后通过一个平面3R机器人的仿真实例,验证了算法的有效性.

关键词： 并联机器人   弹性动力学   有限元  

摘要： 采用有限元理论建立Delta并联机器人柔性构件的运动微分方程,结合机构的运动特点,规定了结点位移的方向,得到机构系统的动力学模型。将机构的真实运动看作名义运动与弹性振动的叠加,同时将动平台的位置和方向误差看作名义运动的摄动,得出动平台位形误差与结点位移的关系方程。在实例中,综合考虑重力、惯性力及阻尼共同作用下的动力响应,得到机构模态频率在工作空间的特性,对动平台的6维误差进行了全面评估。

关键词： 动力学   拉格朗日方程   牛顿-欧拉公式   Gough-Stewart并联机器人   广义坐标  

摘要： 综合采用拉格朗日方程和牛顿-欧拉公式推导了Gough-Stewart并联机器人机构逆动力学模型的封闭解形式.通过选择合适的分支广义坐标,简化了拉格朗日函数对广义坐标的偏导求解,得到了求导矩阵的解析表达式.分析了分支角速度、角加速度轴向分量对机构动力学的影响,仿真结果表明:当机构运动加速度及分支轴向惯量较小时,可以忽略该分量的影响;但当机构运动加速度或者分支轴向惯量较大时,应对传统模型进行修正以满足机构运动高速性和定位精确性的要求.

关键词： Study & teaching of robotics   Mobile communication systems in education  

摘要： The article offers information on the automation and robotics electronic-learning (e-learning) courses launched by Great Britain's Centre for Food Robotics and Automation (CenFRA) in 2011.

关键词： Satisfaction   Training Programs   robotics   Residency   experimentation   Skill Development   Program Evaluation  

摘要： Purpose: We present our experience of training residents in a weekend robotic training program to assess its effectiveness and perceived usefulness. Methods: Bimonthly training sessions were arranged such that residents could sign up for hour-long, weekend training sessions. They are required to complete four training sessions. Five tasks were scored for time and accuracy: Peg-Board, checkerboard, string running, pattern cutting, and suturing. Participants completed surveys (5-point Likert scale) regarding program utility, ease of attendance, and interest in future weekend training sessions. Results: Mean number of trials completed by 19 residents was >4, and 16 completed the trials within an average of 13.7 +/- 8.1 mos. Significant improvements (P < 0.05) were seen in final trials for Peg-Board accuracy (95.8% vs 79.0%), checkerboard deviation (4.8% vs 18.2%), and time (293 s vs 404 s), pattern-cutting time (257 s vs 399 s), and suture time (203 s vs 305 s). Time to previous session correlated with relative improvement in Peg-Board and pattern-cutting time (r = 0.300 and 0.277, P = 0.021 and 0.041), but no specific training interval was predictive of improvement. Residents found the course easy to attend (3.6), noted skills improvement (4.1), and found it useful (4.0). Conclusion: Training in the weekend sessions improved performance of basic tasks on the robot. Training interval had a modest effect on some exercises and may be more important for difficult tasks. This training program is a useful supplement to resident training and would be easy to implement in most programs.

关键词： Behavior coordination   Discrete event systems   discrete event systems (DESs)   fuzzy logic   mobile robotics   Mobile robots   Robot kinematics   Robot sensing systems   Supervisory control  

摘要： In order to incorporate the uncertainty and impreciseness present in real-world event-driven asynchronous systems, fuzzy discrete event systems (DESs) (FDESs) have been proposed as an extension to crisp DESs. In this paper, first, we propose an extension to the supervisory control theory of FDES by redefining fuzzy controllable and uncontrollable events. The proposed supervisor is capable of enabling feasible uncontrollable and controllable events with different possibilities. Then, the extended supervisory control framework of FDES is employed to model and control several navigational tasks of a mobile robot using the behavior-based approach. The robot has limited sensory capabilities, and the navigations have been performed in several unmodeled environments. The reactive and deliberative behaviors of the mobile robotic system are weighted through fuzzy uncontrollable and controllable events, respectively. By employing the proposed supervisory controller, a command-fusion-type behavior coordination is achieved. The observability of fuzzy events is incorporated to represent the sensory imprecision. As a systematic analysis of the system, a fuzzy-state-based controllability measure is introduced. The approach is implemented in both simulation and real time. A performance evaluation is performed to quantitatively estimate the validity of the proposed approach over its counterparts. [ABSTRACT FROM AUTHOR]

关键词： Object recognition   Neural network   Graph partitioning   On-line retraining  

摘要： In this paper, we address object recognition for a mobile robot which is deployed in a multistory building. To move to another floor, a mobile robot should recognize various objects related to an elevator, e.g., elevator control, call buttons, and LED displays. To this end, we propose a neural network based retrainable framework for object recognition, which consists of four components-preprocessing, binary classification, object identification, and outlier rejection. The binary classifier, a key component of our system, is a neural network that can be retrained, the motivation of which is to adapt to varying environments, especially with illuminations. Without incurring any extra process to prepare new training samples for retraining, they are freely obtained as a result of the outlier rejection component, being extracted on-line. To realize a practical system, we adopt a parallel architecture integrating both recognition and retraining processes for seamless object recognition, and furthermore detect and cope with the deterioration of a retrained neural network to ensure high reliability. We demonstrate the positive effect of retraining on the object recognition performance by conducting experiments over hundreds of images obtained in daytime and nighttime.

关键词： MEDICAL rehabilitation   ROBOTICS in medicine   BRAIN imaging   NEUROMUSCULAR system   BRAIN function localization   COGNITION disorders   MEDICAL equipment