视网膜下注射人胚胎干细胞是治疗视网膜变性的一种有效术式,该术式对医生手术操作的精准性、稳定维持能力、安全性均提出了很高的要求.为此,提出一种基于主从式机器人的视网膜下注射系统,辅助医生完成视网膜下注射操作.构建从手机器人的正逆运动学模型,然后进行视网膜下注射手术运动分析,确定从手机器人的运动要求.建立主手和从手机器人之间的运动映射关系,依据运动映射关系推导建立远程运动中心(RCM)点位置调整运动、术中RCM运动的状态切换和分离过程的速度映射模型.通过离体猪眼球视网膜下穿刺注射实验对机器人的精确性和稳定维持能力进行验证,结果表明:机器人辅助操作系统末端注射针具有稳定维持能力和运动的精确性,机器人辅助操作比徒手操作对视网膜造成的创伤更小,注射更稳定.

：To realize RCM (remote center of motion) motion mode required for robot-assisted intraocular surgeries, a novel six-degree-of-freedom series-parallel hybrid mechanism (RP+PPRRP/PPRR) is proposed.Firstly, inspired by the structure of U pair (Universal pair), the parallel configuration (PPRRP/PPRR) is reconstructed by two sets of planar five-bar mechanism (RPPRP) units.After calculating the DOFs (degrees of freedom) and analyzing their characteristics based on screw theory, the capability of RCM motion mode for this mechanism is confirmed.Subsequently, the forward kinematics model and the inverse kinematics model of this mechanism containing RCM parameters are established through coordinate transformation method.Then, according to the configuration of the mechanism, a physical prototype is designed and established.Finally, based on master-slave control method, a motion experiment is performed to verify the correctness of the kinematic model and the adaptability of this mechanism to intraocular surgeries.

Purpose: To determine whether internal limiting membrane peeling damages retinal function in patients with an idiopathic macular hole. Methods: Retrospective case series. Forty-five eyes of 45 idiopathic macular hole patients who underwent vitrectomy with internal limiting membrane peeling with a minimum follow-up of 6 months. Each patient received a complete ophthalmological examination. The eyes were examined by microperimetry MP-3 in the central 20° visual field and optical coherence tomography angiography in the central 6 × 6 mm area. Results: Six months after the surgery, macular hole closed in each patient. Retinal sensitivity decreased significantly in the perifoveal temporal ETDRS sector (from 24.97 ± 2.67–19.98 ± 5.68 dB, P = 0.001) but not in the other sectors. Six patients (13%) developed 24 scotomas, 62.5% presented in the perifoveal temporal sector. Anatomically, bumps in the outer nuclear layer were discovered concurrent with inner retinal dimples on B-scan images, predominantly (76.8%) in the perifoveal temporal sector, which have not been previously reported. The incidence of outer nuclear layer bumps was significantly higher in patients with scotomas than in those without (83% vs. 18%, P = 0.014). Conclusion: Internal limiting membrane peeling induced functional changes specifically in the perifoveal temporal macula. Distortion in the retinal layers is proposed to underly scotomas pathogenesis.

为解决传统的基于三点法的质心测量系统无法应用于带翼展飞行器的问题,提出了一种基于三点方式的任意旋转角质心测量法.为了提高系统测量精度,采用响应面法分析多种随机误差对系统测量精度的综合影响.首先,构建了带翼展飞行器的质量质心测量系统,然后利用随机误差传递公式得到各个随机误差与系统测量精度之间的关系式,并使用响应面法和拉丁超立方抽样法得到多种随机误差与系统测量精度之间的二次项关系式模型,进而依据二次项关系式模型和系统精度指标得到各元器件的精度要求,并分析了满足系统测量误差的旋转角度范围.最后对200 kg、400 kg、800 kg三种质量级别的待测带翼展飞行器在不同旋转角度下进行了多次测量,并将响应面计算结果与理论值进行了对比.对比结果表明,质心测量精度满足系统精度要求,从而验证了任意旋转角度下该测量方法的有效性,以及随机误差与系统测量精度之间的二次项关系式模型的正确性.

AIM To investigate the feasibility of teaching minimally invasive vitreoretinal surgery with a robot-assisted surgical system and a three-dimensional (3D) visualization system. METHODS Enucleated porcine eyes were established as an animal model for removing foreign bodies. Forty medical students were recruited to remove foreign bodies to compare the traditional microscope and the 3D system. One junior resident performed the surgical task with manual and robot-assisted operations on 20 porcine eyes for each group. One senior surgeon evaluated the retinal invasion by a graded injury degree. The learning curve for minimally invasive vitreoretinal surgery was described. RESULTS Compared with the robot-assisted group, the injury degree was higher in the manual group. For the first ten surgeries, the manual and robot-assisted groups had injuries of 2.60±1.35 (4 to 0) and 1.80±1.62 (4 to 0), respectively. For the last ten surgeries, the injury degrees were 1.90±1.20 (3 to 0) and 0.80±0.42 (1 to 0). Considering the manual and robot-assisted groups together, 95%, 75% and 60% of the students considered surgical manipulation with the 3D visualization system to be more comfortable, easier and clearer, respectively. CONCLUSION The robot-assisted surgical system and 3D visualization system may have value in teaching minimally invasive vitreoretinal surgery.

变体飞行器的结构既需要改变气动外形,也需要传递载荷.针对一种变体翼尖的设计需要,使用能量方法,构建了等效力学模型.在实现对波纹板刚度特性等效替代的同时,获得了波纹板整体应变与结构内局部应变的转换关系,从而可以通过对波纹板局部材料进行失效判定,实现对波纹板整体失效应变的预测;经过实验验证,该等效力学模型的解析解与实验值相比平均误差在10％以内.通过对波纹板几何尺寸进行参数分析,获得了单元几何参数对波纹板失效应变和等效刚度的影响关系.最终,针对变体飞行器承载与变形的设计需要,对波纹板进行了优化设计,进一步评估了波纹板结构的强度与刚度特性,为变体翼尖的设计提供了依据.

目的 研究离体猪眼前囊膜经次氯酸钠化学处理后的生物力学参数的变化,为白内障手术初学者和眼科手术机器人的撕囊训练提供更接近于人眼的训练材料.设计实验研究.研究对象新鲜离体猪眼48只、眼库正常人眼晶状体8个.方法 将猪眼随机分为4组,每组12眼,A组为未处理组,0.1％、0.3％、0.5％次氯酸钠溶液处理前囊膜者分别为B、C、D组.8个人眼晶状体为E组.B、C、D组分别在前囊膜表面滴0.1％、0.3％、0.5％次氯酸钠溶液5分钟.一位操作熟练的白内障专科医师使用微力感知撕囊镊对5组晶状体进行连续环形撕囊并对撕囊手感进行问卷评价,通过光纤光栅解调仪实时记录撕囊时的生物力学数据,包括最大撕囊力和平均撕囊力.主要指标撕囊手感评价问卷评分;最大撕囊力和平均撕囊力.结果 医师对猪眼晶状体刺囊及撕囊手感的评分,A组平均分数为(4±0)分,B、C、D组的平均分数均为(3±0)分.最大撕囊力A～E组分别为(34.53±6.02)mN、(29.49±7.00)mN、(28.94±4.71)mN、(26.14±2.39)mN、(24.06±8.18)mN(H=15.07,P=0.005);平均撕囊力分别为(15.58±3.04)mN、(13.48±4.05)mN、(12.67±2.59)mN、(11.40±1.65)mN、(10.98±4.33)mN(H=13.79,P=0.008).A 组与 D 组在最大撕囊力(Z=19.33,P=0.037)、平均撕囊力(Z=20.33,P=0.023)上均存在显著性差异;A组与E组在最大撕囊力(Z=26.58,P=0.004)与平均撕囊力(Z=24.04,P=0.012)上存在显著性差异;其余各组之间最大撕囊力与平均撕囊力无显著性差异.结论 使用0.5％次氯酸钠溶液处理的新鲜离体猪眼晶状体前囊膜的撕囊力最接近于人晶状体前囊膜的撕囊力,处理后的猪眼晶状体前囊膜可用于白内障手术初学者和眼科手术机器人的撕囊训练.

为探究天气和道路等特征,以及交通流、天气、道路及时间等多维动态特征之间的交互作用对实时事故风险预测模型精度的影响,本文基于京哈高速公路北京段的事故数据,以及匹配的交通传感器数据、天气数据和道路特征等,构建4个数据集,分别为只包含交通流变量,包含交通流变量、天气及时间特征变量,包含交通流变量、道路及时间特征变量,包含交通流变量、天气、道路及时间特征变量.从考虑多维动态特征的交互效应出发,基于深度交叉网络,提出一种新的实时事故风险预测模型.结果显示,本文所构建的深度交叉网络模型比其他几种实时事故风险预测方法显示出更高的精度.模型的AUC值(Area Under Curve)可达0.8562,在0.2的概率阈值下,可以正确分类84.26％的非事故数据和77.55％事故数据.结论表明,本文采用的多维动态特征交互样本条件下的深度交叉网络模型能够有效地预测高速公路交通事故,可为我国高速公路安全管理部门提供理论与技术支持.

在视网膜血管注药手术中,手术器械与眼球巩膜刺入孔和视网膜目标血管处产生接触.为保证手术过程中这两处组织的受力在安全阈值内,提出了一种基于多点接触力的机器人约束控制算法.以手术器械轴部与眼球巩膜的接触力(巩膜力)和器械尖端与视网膜血管的接触力(尖端力)为输入,设计了机器人的导纳控制器.导纳控制器输出机器人坐标系下器械尖端处及巩膜接触位置的速度.这两处的运动速度在转换到同一坐标系下后对机器人进行运动约束.在通过导纳算法控制机器人的速度时,提出了一种非线性速度轨迹规划方法,实现速度的平滑变化.所提出的约束控制算法在硅胶眼球模型上进行了模拟视网膜注药试验,试验结果显示在外部扰动存在的情况下,巩膜力和尖端力均被保持在给定阈值之内,表明了所提出的多点力约束机器人控制算法对提高手术安全方面的有效性.

为建立一套高速铁路节能减排的科学评价体系,克服传统方法中只考虑能源消耗和污染物排放的缺点;选取京沪高铁、京沪普铁、京沪高速公路、京杭运河、"虹桥-首都"民航京沪段航线为算例,基于生命周期理论,建立了考虑运力贡献和运输效率的节能减排评价体系,将客货运周转量、运输效率、回收利用率作为正向指标,生命周期阶段能耗与排放为负向指标;并对各待评单元进行信息熵权重处理,基于密切值法进行了节能减排效果评价.计算结果显示土地占用、客货运周转量、运输效率为影响评价结果主要因素,其权重分别为0.10、0.15、0.12;因高速铁路转入运营阶段后,其单位运量能耗和排放大幅降低,同时又能在一定程度上节约运输时间,故而结果显示:高速铁路的节能减排效果最好,高速公路最差.实例表明,建立的评价体系可操作,同时该模型不需确定各主观函数或参量,评价结果客观.

基于广义Maxwell黏弹性模型建立手术器械与眼组织之间的黏弹性接触模型,并通过力松弛实验对接触模型的参数进行辨识.进而在此基础上提出一种导纳控制方法,通过控制手术器械的位移实现对接触力的控制.该方法将传统的导纳控制器替换为比例-积分(PI)控制器,从而将黏弹性接触模型中的理想微分环节替换为1阶微分环节.替换后,在低频段,尤其是频率趋近于0时的幅频响应可得到提升并保持稳定,从而避免幅频响应过低导致的接触力衰减.通过对离体猪眼球进行力控制实验验证了该控制方法的有效性.实验结果表明,阶跃力平均误差约为4.6％,响应时间约为2.5 s,无明显超调,并可实现一定频率的正弦力输出.阶跃力输出精度可以满足机器人辅助眼科手术的要求.

：In surgical operation such as ophthalmic surgery, the micro vibration of the end of the surgical instrument can potentially reduce the required operation force.Therefore, a micro vibration module is proposed that can be integrated into the end-effector of the ophthalmic surgical robot to drive the surgical instrument to generate micro vibration.The micro vibration module is a kind of parallel compliant mechanism.The micro vibration module is composed of three parallel branch chains and a constrained central column.Each parallel branch chain contained two series-driven units, and the micro-vibration operation is performed through the flexible deformation of the drive unit and the central column.Then, the pseudo-rigid body model is used to describe the bending deformation of the driving unit and the center column, and the kinematics model of the micro vibration module is derived.Based on the analysis of the influence of the branch structure parameters on the performance of the micro vibration module, the branch structure parameters are determined.Finally, the performance of the micro vibration module is verified through experiments.Experimental results show that the micro vibration module can perform micro-vibrations at 30 Hz, 14 μm and 30 Hz, 18 μm in the direction of two degrees of freedom.At the same time, the experimental results verify the effectiveness of the proposed method. Key words：ophthalmic microsurgery；parallel

In order to improve the heat transfer characteristics of plane flow casting cooling roller and the transverse thickness uniformity of Fe-Si-Be amorphous strip, a numerical model of axial heat transfer channel was established. Based on the analysis of the current axial flow and heat transfer characteristics of cooling roller, a design of spherical heat transfer channel was proposed. Based on the field synergy theory, the spherical channel was optimized and verified by experiments. The results show that the heat transfer efficiency of the cooling water in the channel decreases gradually along the water flow direction, and the heat transfer mainly occurs near the inner wall of the cooling roller. The temperature in the middle of the existing cooling roller is much higher than that at both ends, and the axial temperature difference is obvious. The spherical channel can strengthen the heat transfer in the middle of the cooling roller, reduce the temperature, thermal deformation and axial deformation difference of the outer wall, and significantly improve the transverse thickness uniformity of the amorphous thin strip. With the decrease of the radius of the sphere, the heat transfer in the middle of the channel increases obviously, but the flow resistance also increases sharply. There is an optimal channel radius based on the comprehensive flow resistance and heat transfer characteristics.

PURPOSE:In eyes with diabetic macular oedema (DME), aqueous humour (AH) cytokine levels before and after anti-vascular endothelial growth factor (VEGF) treatment were compared and correlated with optical coherence tomography structural parameters.METHODS:This prospective study included 56 control patients with cataracts and 83 patients with DME manifesting as diffuse retinal thickening (DRT), cystoid macular oedema and serous retinal detachment (SRD). AH samples were obtained before intravitreal injection of anti-VEGF or cataract surgery. VEGF, interleukin (IL)-6, IL-8, IL-10, interferon-inducible protein 10 (IP-10) and monocyte chemotactic protein 1 (MCP-1) levels were measured by multiplex bead assay. AH cytokine levels, central macular thickness (CMT), number of hyper-reflective foci (HF), continuity of external limiting membrane and ellipsoid zone (EZ) and best-corrected visual acuity were evaluated.RESULTS:In SRD, IL-6 and MCP-1 levels and HF were increased (all p < 0.05) compared to DRT. At baseline, the number of HF was correlated with VEGF, IL-6, IL-8, IP-10 and MCP-1 (all p < 0.05). Eyes sensitive to anti-VEGF treatment had high baseline levels of VEGF, MCP-1, HF and many EZ disruptions (all p < 0.05). DME patients with normal VEGF levels but with high levels of IL-8, IP-10 and MCP-1 (all p < 0.05) had little change in CMT after anti-VEGF treatment (p = 0.678).CONCLUSIONS:AH concentrations of some inflammatory cytokines in DME were differentially expressed among the three DME morphologies. HF was associated with VEGF and other inflammatory cytokine levels. Multiple HF at baseline predicted a significant decrease in CMT, and eyes with normal VEGF but increased inflammatory cytokines may be insensitive to anti-VEGF treatment.

根据某弹射系统的空间约束与作业要求,提出了基于遗传算法的并联弹簧机构的优化设计方法.根据弹射要求,进行并联弹簧机构的弹簧选型与结构设计构建弹射偏载虚拟样机,通过无摩擦力、有摩擦力的弹射仿真分析确定合理弹簧布置.根据弹簧及运动部件的受力情况,进行弹簧布局优化,提出遗传算法的多目标优化函数,并作遗传算法求解计算,得到并联弹簧的最优布局,仿真结果显示弹射效率显著提高,满足弹射作业需求.进行优化前与优化后的弹射实验证明建模仿真以及所提出的并联弹簧机构优化设计方法有效.

为改善平面流铸冷却辊的换热特性,提高Fe-Si-B非晶薄带的横向厚度均匀性,建立了冷却辊轴向换热通道数值计算模型.在分析现有通道流动换热特性基础上,提出一种球面形换热通道设计方法.基于场协同理论,综合换热与流阻,对所提球面形通道进行优化,并进行实验验证.结果表明:通道内冷却水换热效率沿水流方向逐渐下降,与冷却辊换热主要发生在靠近冷却辊内壁位置,现有冷却辊宽度中部温度远大于两端,轴向温差明显;球面形通道可以加强冷却辊中部换热,降低外壁温度、热变形和轴向变形差,进而改善非晶薄带横向厚度均匀性;随着球面半径的减小,通道中部换热明显增强,但流阻随之急剧增大;综合流阻与换热特性,存在最优通道优化半径.

In the Ophthalmic microsurgery, as the contact forces between tool and tissue are too small to perceive and the excessive operating force might lead to tissue damage, an FBG-based two-dimensional micro-force sensor is developed. After the force-wavelength relationship is determined and the temperature effect to the wavelength is discussed, an algorithm is developed to cancel the temperature effect. A calibration experiment is performed on a self-developed micro-force sensor calibration platform (the measuring accuracy is 0.42 mN). The sensor is integrated to the end of an ophthalmic surgical forceps, which was used to perform continuous curvilinear capsulorhexis (CCC) on isolated pig eyeballs to obtain the force-time curves. By analyzing 19 sets of data, the average value of the maximum capsular force was 22.43 mN. The research laid the foundation for precise operation of ophthalmic surgery and micro-force control of surgical robots.

为提高载具内的物料装填效率,提出了一种在载具内受限空间中使用的新型圆柱物料装填机器人,并通过优化关节轨迹,对机器人末端残余振动进行抑制。首先,给出物料装填机器人的总体设计方案和工作流程。然后,结合物料装填机器人的结构特点,应用拉格朗日方法建立封闭形式的刚柔耦合动力学模型,并应用模态分析方法得到机器人末端动态响应计算方法。最后,以物料装填机器人关节残余弹性势能最小为优化目标,使用最大最小蚂蚁系统,对机器人关节轨迹进行优化,并对优化结果进行仿真验证。仿真结果表明,优化后的关节轨迹,在满足快速装填要求的基础上,可以降低约34.4%的关节残余弹性势能和约37.6%的机器人末端振动振幅。

建立了四旋翼倾转飞行器旋翼、机翼、机身的非线性气动模型和飞行动力学模型,并在Matlab/Simulink环境下搭建了仿真模型,根据仿真模型计算各个操纵面的操纵效率,确定了不同状态下各个通道需要用到的操纵方式,结合飞行动力学模型和操纵方式,在纵向通道上进行了全包线的配平计算,表明了操纵策略的可行性.

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.