关键词： Passive walking   Gait analysis   Roll-over shape   Prosthetic foot   Bifurcation diagrams   Nonlinear dynamics  

摘要： The 'heel to toe' rolling contact has a great influence on the dynamics of biped robots. Here this contact is modelled using the roll-over shape defined in the local co-ordinate system aligned with the stance leg. The roll-over shape is characterised by six constants: forefoot, midfoot and hindfoot gains and length values. A piecewise parabolic polynomial constructed from these six values is able to match the realistic roll-over shape with continuous slope and variable curvature. The effect of these constants and the roll-over shape arc length has been studied on various gait descriptors such as average velocity, step period, inter-leg angle (and hence step length), mechanical energy. The bifurcation diagrams have been plotted for point feet and different gain values. The insight gained by studying the bifurcation diagrams for different gain and length values is not only useful in understanding the stability of the biped walking process but also in the design of prosthetic feet. The discovery of 'critical values' for the length and mass ratios for the inter-leg angle delta (and hence step length) bifurcation diagrams, or a 'critical value' for forefoot gain in the step period bifurcation diagram, is of particular interest as it would mean a constant step length or step period for a range of acceptable values of forefoot and hindfoot gains. The dependence of the horizontal roll-over shape length and hindfoot/forefoot gains on the actual stance leg angular velocity theta(s) and angular displacement (theta(s)) values along with the corresponding existence of critical values has also been demonstrated. (C) 2013 Elsevier Inc. All rights reserved.

摘要： sMinimally invasive lung resections especially segmentectomy is becoming a more employed procedure everyday. We evaluated our perioperative database of complete minimally invasive segmentectomies to compare the two different minimally invasive techniques.

关键词： 中小学生   科技创新   湖北省   机器人   武汉市   青少年   竞赛   教育基地  

摘要： 2313年5月26日上午，第28届湖北省青少年科技创新大赛机器人竞赛（中夏杯）暨武汉市第十届中小学生机器人竞赛在武汉红心国防教育基地举办。本次活动由湖北省科技协会、湖北省教育厅、湖北省科技厅、共青团湖北省委等机构主办。

关键词： 全地面起重机   塔臂工况   回转   机器人动力学   主臂强度  

摘要： 全地面起重机塔臂工况下回转起制动过程将对主臂产生较大的扭转冲击等附加动载荷作用,建立全地面起重机塔臂工况臂架系统力学模型,基于机器人动力学理论建立吊重摆振动力学方程,计算吊重在变幅平面和回转平面内的偏摆角,采用第四强度理论计算主臂应力。研究结果表明起动加速时间、吊重绳长对主臂强度有显著影响,不同的塔臂仰角和塔臂长度对主臂强度的影响程度不同。所得结论可为全地面起重机结构设计和现场操作控制提供参考。

关键词： whole-body movement   humanoid robot   inverse dynamics   human posture  

摘要： "An advanced robotics motion generation framework for inferring the organisation of human movements."Computer Methods in Biomechanics and Biomedical Engineering, 16(sup1), pp. 177–178

关键词： 油罐清洗机器人   运动学   动力学   仿真研究  

摘要： 油罐清洗机器人是一种针对油罐罐底油泥实施自动化清洗而研发的特殊机器人。通过建立适当坐标系,运用D-H参数法对其进行了运动学分析,得出末端执行装置位姿方程,运用拉格朗日方法求解得出其整体动力学方程。通过计算机仿真实验,验证了运动学方程和动力学方程的准确性,能够描述油罐清洗机器人的运动特性,在该机器人的运动控制和系统稳定性分析方面具有一定的参考价值。

关键词： total hip arthroplasty   femoral head resurfacing   impingement   stability   soft tissue  

摘要： We identified and compared the impingent-free range of motion (ROM) and subluxation potential for native hip, femoral head resurfacing (FHR), and total hip arthroplasty (THA). These constructs were also compared both with and without soft tissue to elucidate the role of the soft tissue. Five fresh-frozen bilateral hip specimens were mounted to a six-degree of freedom robotic manipulator. Under load-control parameters, in vivo mechanics were recreated to evaluate impingement free ROM, and the subluxation potential in two at risk positions for native hip, FHR, and THA. Impingement-free ROM of the skeletonized THA was greater than FHR for the anterior subluxation position. For skeletonized posterior subluxations, stability for THA and FHR constructs were similar, while a different pattern was observed for specimens with soft tissues intact. FHR constructs were more stable than THA constructs for both anterior and posterior subluxations. When the femoral neck is intact the joint has an earlier impingement profile placing the hip at risk for subluxation. However, FHR design was shown to be more stable than THA only when soft tissues were intact. (c) 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:11081115, 2013

关键词： URINARY calculi   LAPAROSCOPY   UROLOGY   SURGICAL complications   SURGICAL robots   OUTCOME assessment (Medical care)  

摘要： OBJECTIVE To study the feasibility of robot-assisted laparoscopic ureterolithotomy for large (>2 cm) or impacted lower ureteral stones and the immediate outcome measures such as the stone-free rate and occurrence of intra-and postoperative complications. MATERIALS AND METHODS From April 2010 to August 2012, 52 robotic stone surgeries were performed in our department. Robot-assisted laparoscopic ureterolithotomy was performed in 16 patients for large (>2 cm) or impacted lower ureteral stones. RESULTS The stone was most commonly located in the juxtavesical position in all 16 patients. The average stone size was 2.2 cm, and all stones were impacted. The mean operative time was 45.3 minutes (range, 38-63), including stent placement time, and the mean blood loss was 10 mL. The mean console time was 20.3 minutes. No conversion to an open procedure was required. CONCLUSION Robot-assisted laparoscopic ureterolithotomy for large, impacted, lower ureteral stones is an acceptable alternative. The ease of surgery and shorter operative times are significant advantages compared with the laparoscopic approach. UROLOGY 82: 95-99, 2013. (C) 2013 Elsevier Inc.

关键词： tumor tissue   Tubular structures   Chaperonins   Adenosine Triphosphate   biodegradation   Intracellular   Nanomedicine   Fueling   Release   nanocarrier   mechanical force  

摘要： The development of nanocarriers that selectively release guest molecules on sensing a particular biological signal is being actively pursued in nanomedicine for diagnostic and therapeutic purposes. Here we report a protein-based nanocarrier that opens in the presence of intracellular adenosine-5'-triphosphate (ATP). The nanocarrier consists of multiple barrel-shaped chaperonin units assembled through coordination with Mg2+ into a tubular structure that protects guest molecules against biological degradation. When its surface is functionalized with a boronic acid derivative, the nanocarrier is able to enter cells. The hydrolysis of intracellular ATP into adenosine-5'-diphosphate (ADP) induces conformational changes of the chaperonin units, which in turns generate a mechanical force that leads to the disassembly of the tube and release of the guests. This scission occurs with a sigmoidal dependence on ATP concentration, which means that the nanocarrier can differentiate biological environments in terms of the concentration of ATP for selective guest release. Furthermore, biodistribution tests reveal preferential accumulation of the nanocarriers in a tumour tissue.