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机械手时间最优脉动连续轨迹规划算法 被引量:89
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作者 朱世强 刘松国 +1 位作者 王宣银 王会方 《机械工程学报》 EI CAS CSCD 北大核心 2010年第3期47-52,共6页
为使机械手的作业效率达到最优,同时确保运动的平稳性,提出一种新的最优轨迹规划方法。通过逆运动学运算得到与任务空间轨迹对应的关节空间位置序列,采用7次B样条曲线插值方法构造启动和停止运动参数可控,且速度、加速度和脉动均连续的... 为使机械手的作业效率达到最优,同时确保运动的平稳性,提出一种新的最优轨迹规划方法。通过逆运动学运算得到与任务空间轨迹对应的关节空间位置序列,采用7次B样条曲线插值方法构造启动和停止运动参数可控,且速度、加速度和脉动均连续的关节轨迹。将机械手运动学约束转化为B样条曲线的控制顶点约束,采用序列二次规划方法求解最优运动时间节点,进而规划出满足非线性运动学约束的时间最优脉动连续轨迹。仿真和试验结果表明,提出的轨迹规划方法为关节控制器提供理想的轨迹,使机械手在最短的时间平稳地跟踪任务空间的任意指定轨迹。 展开更多
关键词 机械手 轨迹规划 时间最优 脉动连续 序列二次规划
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一种新型物料装填机器人的设计与轨迹优化 被引量:5
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作者 郑昱 广晨汉 +1 位作者 李前 杨洋 《兵工学报》 EI CAS CSCD 北大核心 2020年第4期763-770,共8页
为提高车辆等载具内的物料装填效率,设计一种车内受限空间中使用的圆柱物料装填机器人,并对机器人的关节轨迹进行优化。在考虑圆柱物料输送要求和车内空间限制的基础上,提出物料装填机器人总体设计方案,给出机器人工作时的关节运动流程... 为提高车辆等载具内的物料装填效率,设计一种车内受限空间中使用的圆柱物料装填机器人,并对机器人的关节轨迹进行优化。在考虑圆柱物料输送要求和车内空间限制的基础上,提出物料装填机器人总体设计方案,给出机器人工作时的关节运动流程。建立机器人运动学模型,对机器人的工作空间进行分析。使用分段高阶多项式函数拟合机器人关节运动轨迹,采取插值时间变量代替系数变量的简化求解方法和粒子群算法优化关节轨迹。研究结果表明,该物料装填机器人工作空间可覆盖车内空间且满足车内空间限制,优化后的关节轨迹可平稳快速地完成物料装填作业。 展开更多
关键词 物料装填机器人 有限空间 脉动连续 轨迹优化 粒子群算法
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Continuous regional arterial infusion and laparotomic decompression for severe acute pancreatitis with abdominal compartment syndrome 被引量:17
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作者 Zhi-Gang Deng Jian-Yin Zhou Zhen-Yu Yin You-Yuan Peng Fu-Qiang Wang Xiao-Min Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第44期4911-4916,共6页
AIM:To evaluate the therapeutic effects of abdominal decompression plus continuous regional arterial infusion(CRAI) via a drug delivery system(DDS) in severe acute pancreatitis(SAP) patients with abdominal compartment... AIM:To evaluate the therapeutic effects of abdominal decompression plus continuous regional arterial infusion(CRAI) via a drug delivery system(DDS) in severe acute pancreatitis(SAP) patients with abdominal compartment syndrome(ACS).METHODS:We presented our recent experience in 8 patients with SAP.The patients developed clinical ACS,which required abdominal decompression.During the operation,a DDS was inserted into the peripancreatic artery(the catheter was inserted from the right gastroepiploic artery until it reached the junction between the pancreaticoduodenal and gastroduodenal artery).Through this DDS,a protease inhibitor,antibiotics and octreotide were infused continuously.The duration of the regional artery infusion ranged from 8 to 41 d.The outcomes and the changes in the APACHE Ⅱ score,computed tomography(CT) severity index and intraabdominal pressure(IAP) of the patients were retrospectively evaluated.RESULTS:Eight patients with an initial APACHE Ⅱ score of 18.9(range,13-27) and a Balthazar CT severity index of 9.1(range,7-10) developed severe local and systemic complications.These patients underwent subsequent surgical decompression and CRAI therapy because of intra-abdominal hypertension(IAH).After a mean interval of 131.9 ± 72.3 d hospitalization,7 patients recovered with decreased APACHE Ⅱ scores,CT severity indexes and IAP.The mean APACHE Ⅱ score was 5.4(range,4-8),the CT severity index was 2.3(range,1-3),and IAP decreased to 7.7 mmHg(range,6-11 mmHg) 60 d after operation.One patient died of multiple organ failure 1 wk after surgery.CONCLUSION:CRAI and laparotomic decompression might be a therapeutic option for SAP patients with ACS. 展开更多
关键词 Severe acute pancreatitis Arterial infusion Laparotomy Abdominal compartment syndrome
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Photoassociation of NaRb with an asymmetric laser pulse
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作者 ZHANG ChangZhe ZHENG Bin +2 位作者 NIU YuQuan WEI Wei MENG QingTian 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2014年第10期1879-1884,共6页
We investigate the photoassociation dynamics of cold NaRb molecule controlled by an asymmetric laser pulse called slowly-turned-on and rapidly-turned-off(STRT) laser pulse. This new shaped laser pulse has a remarkable... We investigate the photoassociation dynamics of cold NaRb molecule controlled by an asymmetric laser pulse called slowly-turned-on and rapidly-turned-off(STRT) laser pulse. This new shaped laser pulse has a remarkable merit, compared with the typical Gauss-type pulses, so that we can efficiently associate molecules with the state expected instead of going back to the continuum state. Using the three-state model, we solve the quantum mechanical equation with the "split operator-Fourier transform" method under the rotating-wave approximation(RWA) in propagation of the wave packet. By the projection of the obtained wave function onto each vibrational state, we can get the vibrational population of the ground electronic state. The results reveal that, with the STRT laser pulse, an efficient photoassociation process can be achieved and the vibrational distribution in the ground state can be controlled by the laser parameters. 展开更多
关键词 PHOTOASSOCIATION time-dependent wave packet method asymmetric laser pulse NaRb
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