Developing effective and practical electrocatalyst under industrial electrolysis conditions is critical for renewable hydrogen production.Herein,we report the self-supporting NiFe LDH-MoS_(x) integrated electrode for ...Developing effective and practical electrocatalyst under industrial electrolysis conditions is critical for renewable hydrogen production.Herein,we report the self-supporting NiFe LDH-MoS_(x) integrated electrode for water oxidation under normal alkaline test condition(1 M KOH at 25℃)and simulated industrial electrolysis conditions(5 M KOH at 65℃).Such optimized electrode exhibits excellent oxygen evolution reaction(OER)performance with overpotential of 195 and 290 mV at current density of 100 and 400 mA·cm^(-2) under normal alkaline test condition.Notably,only over-potential of 156 and 201 mV were required to achieve the current density of 100 and 400mA·cm^(-2) under simulated industrial electrolysis conditions.No significant degradations were observed after long-term durability tests for both conditions.When using in two-electrode system,the operational voltages of 1.44 and 1.72 V were required to achieve a current density of 10 and 100 mA·cm^(-2) for the overall water splitting test(NiFe LDH-MoS_(x)/INF||20%Pt/C).Additionally,the operational voltage of employing NiFe LDH-MoS_(x)/INF as both cathode and anode merely require 1.52 V at 50mA·cm^(-2) at simulated industrial electrolysis conditions.Notably,a membrane electrode assembly(MEA)for anion exchange membrane water electrolysis(AEMWEs)using NiFe LDH-MoS_(x)/INF as an anode catalyst exhibited an energy conversion efficiency of 71.8%at current density of 400 mA·cm^(-2)in 1 M KOH at 60℃.Further experimental results reveal that sulfurized substrate not only improved the conductivity of NiFe LDH,but also regulated its electronic configurations and atomic composition,leading to the excellent activity.The easy-obtained and cost-effective integrated electrodes are expected to meet the large-scale application of industrial water electrolysis.展开更多
This paper proposes an uncalibrated workpiece positioning method for peg-in-hole assembly of a device using an industrial robot.Depth images are used to identify and locate the workpieces when a peg-in-hole assembly t...This paper proposes an uncalibrated workpiece positioning method for peg-in-hole assembly of a device using an industrial robot.Depth images are used to identify and locate the workpieces when a peg-in-hole assembly task is carried out by an industrial robot in a flexible production system.First,the depth image is thresholded according to the depth data of the workpiece surface so as to filter out the background interference.Second,a series of image processing and the feature recognition algorithms are executed to extract the outer contour features and locate the center point position.This image information,fed by the vision system,will drive the robot to achieve the positioning,approximately.Finally,the Hough circle detection algorithm is used to extract the features and the relevant parameters of the circular hole where the assembly would be done,on the color image,for accurate positioning.The experimental result shows that the positioning accuracy of this method is between 0.6-1.2 mm,in the used experimental system.The entire positioning process need not require complicated calibration,and the method is highly flexible.It is suitable for the automatic assembly tasks with multi-specification or in small batches,in a flexible production system.展开更多
由于六自由度机器人在装配序列规划中存在顶角叶片重力矩差难以保证、叶片重力矩分布不够均衡的问题,以至于避障过程中出现碰撞。为此,提出工业机器人六自由度装配序列规划下避障研究。通过分析六自由度机器人装配序列中,顶角叶片重力...由于六自由度机器人在装配序列规划中存在顶角叶片重力矩差难以保证、叶片重力矩分布不够均衡的问题,以至于避障过程中出现碰撞。为此,提出工业机器人六自由度装配序列规划下避障研究。通过分析六自由度机器人装配序列中,顶角叶片重力矩差和叶片重力矩分布产生的干涉关系,将装配平稳性、方向调整次数及更换装配工具的频次作为约束条件,设置干涉关系矩阵和适应度函数,以判断装配序列方案是否达到最佳;在装配方案达到最佳后,通过离散化萤火虫算法获取六自由度机器人装配序列最优解;根据该结果检测六自由度机器人碰撞结果,并采用优化随机树节点扩展控制及扩展能力检测的改进快速搜索随机树算法(Rapidly-exploring Random Tree,RRT*)来对所得装配序列进行调整修正,实现工业机器人六自由度装配序列规划下避障研究。实验结果证明:该方法可获取装配效率高、成本小的六自由度机器人装配序列;可以快速规划出最佳六自由度机器人避障路径,有效地避开障碍物,且精度较高、误差较小、实用性较强。展开更多
文摘Developing effective and practical electrocatalyst under industrial electrolysis conditions is critical for renewable hydrogen production.Herein,we report the self-supporting NiFe LDH-MoS_(x) integrated electrode for water oxidation under normal alkaline test condition(1 M KOH at 25℃)and simulated industrial electrolysis conditions(5 M KOH at 65℃).Such optimized electrode exhibits excellent oxygen evolution reaction(OER)performance with overpotential of 195 and 290 mV at current density of 100 and 400 mA·cm^(-2) under normal alkaline test condition.Notably,only over-potential of 156 and 201 mV were required to achieve the current density of 100 and 400mA·cm^(-2) under simulated industrial electrolysis conditions.No significant degradations were observed after long-term durability tests for both conditions.When using in two-electrode system,the operational voltages of 1.44 and 1.72 V were required to achieve a current density of 10 and 100 mA·cm^(-2) for the overall water splitting test(NiFe LDH-MoS_(x)/INF||20%Pt/C).Additionally,the operational voltage of employing NiFe LDH-MoS_(x)/INF as both cathode and anode merely require 1.52 V at 50mA·cm^(-2) at simulated industrial electrolysis conditions.Notably,a membrane electrode assembly(MEA)for anion exchange membrane water electrolysis(AEMWEs)using NiFe LDH-MoS_(x)/INF as an anode catalyst exhibited an energy conversion efficiency of 71.8%at current density of 400 mA·cm^(-2)in 1 M KOH at 60℃.Further experimental results reveal that sulfurized substrate not only improved the conductivity of NiFe LDH,but also regulated its electronic configurations and atomic composition,leading to the excellent activity.The easy-obtained and cost-effective integrated electrodes are expected to meet the large-scale application of industrial water electrolysis.
文摘This paper proposes an uncalibrated workpiece positioning method for peg-in-hole assembly of a device using an industrial robot.Depth images are used to identify and locate the workpieces when a peg-in-hole assembly task is carried out by an industrial robot in a flexible production system.First,the depth image is thresholded according to the depth data of the workpiece surface so as to filter out the background interference.Second,a series of image processing and the feature recognition algorithms are executed to extract the outer contour features and locate the center point position.This image information,fed by the vision system,will drive the robot to achieve the positioning,approximately.Finally,the Hough circle detection algorithm is used to extract the features and the relevant parameters of the circular hole where the assembly would be done,on the color image,for accurate positioning.The experimental result shows that the positioning accuracy of this method is between 0.6-1.2 mm,in the used experimental system.The entire positioning process need not require complicated calibration,and the method is highly flexible.It is suitable for the automatic assembly tasks with multi-specification or in small batches,in a flexible production system.
文摘由于六自由度机器人在装配序列规划中存在顶角叶片重力矩差难以保证、叶片重力矩分布不够均衡的问题,以至于避障过程中出现碰撞。为此,提出工业机器人六自由度装配序列规划下避障研究。通过分析六自由度机器人装配序列中,顶角叶片重力矩差和叶片重力矩分布产生的干涉关系,将装配平稳性、方向调整次数及更换装配工具的频次作为约束条件,设置干涉关系矩阵和适应度函数,以判断装配序列方案是否达到最佳;在装配方案达到最佳后,通过离散化萤火虫算法获取六自由度机器人装配序列最优解;根据该结果检测六自由度机器人碰撞结果,并采用优化随机树节点扩展控制及扩展能力检测的改进快速搜索随机树算法(Rapidly-exploring Random Tree,RRT*)来对所得装配序列进行调整修正,实现工业机器人六自由度装配序列规划下避障研究。实验结果证明:该方法可获取装配效率高、成本小的六自由度机器人装配序列;可以快速规划出最佳六自由度机器人避障路径,有效地避开障碍物,且精度较高、误差较小、实用性较强。