关键词： Cable-driven robot   Kinematics model   Dynamics model   Positioning accuracy   End-effector attachment  

摘要： This paper tackles the problem of improving the connection between the fixed frame and the end-effector of planar and spatial cable-driven robots. A new design concept is detailed, which consists in adding pulleys to the attachment between the cables and the end-effector. These reflective pulleys must have the same radius as the ones at the frame in order to compensate their geometry. Without this modification in the end-effector, the usual simplification of the point-to-point method used to model the connection between frame and end-effector leads to significant errors in the Kinematics and Dynamics of the system due to the fact that the geometry of the frame pulleys is disregarded. By adding the reflective pulleys in the end-effector, the equations of the Kinematics and Dynamics of the real system are equivalent to those of the point-to-point model, and therefore, this simplified method can be used without inherent errors. This solution may be of great importance for computational issues because it leads to codes that may run at real time. An analytical proof of the equivalence of both models is presented. Finally, experimental results have been conducted for both, planar and spatial cable-robots, in order to illustrate the advantages of using this novel design concept for the connection between the end-effector and the fixed frame. (C) 2017 Elsevier Ltd. All rights reserved.

关键词： Space robot   dynamics modeling   active control   Jourdain's velocity variation principle   computed torque control method  

摘要： With the development of space exploration, researches on space robot will cause more attentions. However, most existing researches about dynamics and control of space robot concern planar problem, and the effect of flexible panel on dynamics of the system is not considered. In this article, dynamics modeling and active control of a 6-DOF space robot with flexible panels are investigated. Dynamic model of the system is established based on the Jourdain's velocity variation principle and the single direction recursive construction method. The computed torque control method is used to design point-to-point active controller of the space robot. The validity of the dynamic model is verified through the comparison with ADAMS software;the effects of panel flexibility on the system performance and the active controller design are studied in detail. Simulation results indicate that the proposed model is effective to describe the dynamics of space robot;panel flexibility has large influence on the dynamic behavior of space robot;the designed controller can effectively make the robot reach a specified position and the elastic vibration of the panels may be suppressed simultaneously.

关键词： ROBOTS  

摘要： The article offers brief information on the HC10 robot from Yaskawa Motoman Canada Ltd.

关键词： Discrete-time system   Neural networks   Robot manipulator   Adaptive control   Dynamics uncertainties  

摘要： In this paper, a novel optimal adaptive radial basis function neural network (RBFNN) control has been investigated for a class of multiple-input-multiple-output (MIMO) nonlinear robot manipulators with uncertain dynamics in discrete time. To facilitate digital implementations of the robot controller, a robot model in discrete time has been employed. A high order uncertain robot model is able to be transformed to a predictor form, and a feedback control system has been then developed without noncausal problem in discrete time. The controller has been designed by an adaptive neural network (NN) based on the feedback system. The adaptive RBFNN robot control system has been investigated by a critic RBFNN and an actor RBFNN to approximate a desired control and a strategic utility function, respectively. The rigorous Lyapunov analysis is used to establish uniformly ultimate boundedness (UUB) of closed-loop signals, and the high-quality dynamic performance against uncertainties and disturbances is obtained by appropriately selecting the controller parameters. Simulation studies validate that the proposed control scheme has performed better than other available methods currently, for robot manipulators.

关键词： micro and nanoscale devices   robotics   soft actuators  

摘要： This review comprises a detailed survey of ongoing methodologies for soft actuators, highlighting approaches suitable for nanometer-to centimeter-scale robotic applications. Soft robots present a special design challenge in that their actuation and sensing mechanisms are often highly integrated with the robot body and overall functionality. When less than a centimeter, they belong to an even more special subcategory of robots or devices, in that they often lack on-board power, sensing, computation, and control. Soft, active materials are particularly well suited for this task, with a wide range of stimulants and a number of impressive examples, demonstrating large deformations, high motion complexities, and varied multifunctionality. Recent research includes both the development of new materials and composites, as well as novel implementations leveraging the unique properties of soft materials.

关键词： loop structures   smart materials   smart textiles   soft morphing   soft robots  

摘要： A loop-linked structure, which is capable of morphing in various modes, including volumetric transformation, is developed based on knitting methods. Morphing flowers (a lily-like, a daffodil-like, gamopetalous, and a calla-like flower) are fabricated using loop patterning, and their blooming motion is demonstrated by controlling a current that selectively actuates the flowers petals.

关键词： loop structures   smart materials   smart textiles   soft morphing   soft robots  

摘要： In article number 1606580, Min-Woo Han and Sung-Hoon Ahn report soft morphing structures, in which loop-linked structures made from thermally responsive fibers allow the creation of three-dimensional morphologies, including flowers. Based on the design methodology of loop patterning, the proposed morphing structures enable three-dimensional volumetric transformation as well as bending, twisting, and torsional deformation, through functional fiber actuation.

关键词： 可重构机器人   层序列数组   模块化动力学建模   牛顿-欧拉方法TP242.2  

摘要： 可重构模块化机器人系统具有单元模块种类多、结构复杂且构型种类多样等特点,由于每次重构其动力学方程随构型变化而发生改变,使得传统建模方法不适合直接应用到其建模过程中。针对这一问题,文章提出一种具有模块化思想的动力学模型自动生成方法。首先根据各模块的特点采用旋量理论建立单元模块运动学、动力学模型,然后利用层序列数组(Layer Sequence Array)对系统拓扑结构及构型信息进行表达,确定各模块之间的相互作用关系,并结合牛顿-欧拉公式给出了可重构机器人动力学自动生成算法。最后通过仿真计算验证建模方法的可行性和有效性。

关键词： 参数辨识   线性最小二乘法   粒子群算法   机器人   机械臂  

摘要： 提出了一种对机器人机械臂各关节的动力学参数进行离线识别的新方法。该方法在实现途径上简单有效,无需附加传感器。通过控制机械臂各待辨识关节按照周期性傅里叶级数轨迹运动,读取关节电流以获取关节力矩值便可实现对机械臂连杆动力学参数进行识别。该识别算法通过将待识别参数分为线性部分和非线性部分,并对其分别采用线性最小二乘法和粒子群算法进行解算。实现过程简单,不仅能识别机械臂的动力学参数,还能识别动摩擦系数和黏滞摩擦系数。通过在新松七自由度协作机器人上进行实验,验证了该方法的可行性和有效性。

关键词： 机器人竞赛   岭南画派   教育技术中心   竞赛项目   中小学师生   指导思想   大项   虚实结合   比赛现场   顺德  

摘要： 2017年4月9日上午,由广东省教育技术中心主办的第十五届广东省中小学电脑机器人活动虚拟机器人竞赛在广州市岭南画派纪念中学隆重举办。本次竞赛项目包括智能快递、超级轨迹、九宫探险、全能工程挑战赛（虚实结合）四个大项12个小项。