辅助腹腔镜手术机器人穿刺孔位置标定研究

从临床应用的角度出发,针对研制的带有主被动关节的辅助腹腔镜手术机器人被动姿态关节的特点,提出了一种标定患者腹壁穿刺孔位置相对机器人基础坐标系坐标的方法.在机器人小臂的下方安装2个不同倾角的激光源,通过几何关系间接测得患者穿刺孔相对机器人基础坐标系的位置,为机器人控制功能的实现提供了必要的腹腔镜姿态信息.对机器人标定系统进行了实验研究,分析了标定误差产生的原因,研究结果表明该方法可以准确标定出穿刺孔相对机器人基础坐标系的位置,机器人能够完成腹腔镜位姿控制的任务.     

Identification of tissue types and boundaries with a fiber optic force sensor

The absence of tactile force information at the tip of a medical instrument makes precise minimally invasive surgery difficult and is prone to resulting in serious outcomes. In this paper, a fiber optic force sensor is fabricated based on Fabry-Perot interferometry and integrated with a puncture needle. The force sensor is attached to the needle tip, where interactive force arises as it inserts into soft tissue. Needle insertion experiments have been conducted on ex vivo swine liver and belly with the calibrated force sensor. Using wavelet transform method, the acquired force data are analyzed and used to identify layered tissue types and boundaries. We found that the force amplitudes are not always identical, but the patterns of forces are almost the same, which enables us to identify layered tissues and to realize a safe needle insertion procedure under robot control.     

芳纶短纤维在轮胎性能改进中的应用

通过研究芳纶短纤维对天然橡胶(NR)性能的影响,探讨芳纶短纤维在轮胎性能改进中的应用。结果表明:芳纶短纤维可以提高NR胶料300%定伸应力和撕裂强度;可以改善胎侧胶的抗刺扎性能和抗切割性能,胎侧胶添加芳纶短纤维的矿山轮胎使用寿命延长;芳纶短纤维在胎侧胶中的适合用量为3～4份。     

Texture of rehydrated dried bell peppers modified by low-temperature blanching and calcium addition

Diced green bell pepper was blanched twice, once at 51–79 °C for 19–61 min, and once at 95 °C for 3 min, and dried. The firmness of rehydrated samples was measured by puncture, and optimum conditions assessed by response surface methodology. The optimized model showed that, blanching at 65 °C for 49 min gave a 64% increase in puncture force over the control. The optimum temperature was used to evaluate the effect of adding CaCl₂. The dices were blanched twice, once at 65 °C for 3 min in either 0 or 4% CaCl₂, secondly in either 0 or 2% CaCl₂ solution at 95 °C for 3 min. In the second case the dices had been held at room temperature for 0–30 min before treatment. Adding CaCl₂ increased puncture force significantly ( P  ≤ 0.05). The best results, those which gave greatest firmness, were obtained by blanching at 65 °C for 3 min in 4% CaCl₂, holding for 16 min after blanching, followed by a secondary blanching at 95 °C in 2% CaCl₂.     

Thermal characteristics of the self-healing response in poly(ethylene-co-methacrylic acid) copolymers.

A class of poly(ethylene-co-methacrylic acid) (EMAA) copolymers and ionomers has shown the unique ability to instantaneously self-heal following ballistic puncture. It is noteworthy that the thermomechanical healing process active in these materials appears to be significantly different in capability and mechanism than any of the other self-repairing systems studied. To better understand this phenomenon, the thermal response during EMAA self-healing was examined. Tests of various damage types, including sawing, cutting and puncture, revealed high-energy transfer damage modes to produce heat and store energy favourable to healing. DSC probed healed specimens revealing they had reached the viscoelastic melt believed requisite to healing response. Low-temperature ballistic experiments demonstrated films continue healing even when punctured at -30 degrees C; analysis showed healing efficacy comparable to room temperature, holding significant pressures of approximately 3 MPa. At the lowest temperature, brittle fracture occurred in one material indicating insufficient heat transfer to store recoverable energy. In total, the results supported the defined healing model and provided additional information on the healing process in both its thermal dependence and general mechanism. Finally, a new DSC method was developed for probing the thermal history of healed films which may lead to a more complete mechanistic model.     

基于多目标粒子群优化算法的斜尖柔性针穿刺路径规划

针对斜尖柔性针在复杂环境下由入针点到达病灶位置的穿刺路径问题,提出一种基于多目标粒子群优化算法(MOPSO)的路径规划方法.对软组织内柔性针运动学模型进行分析,构建控制量与柔性针穿刺路径的关系;分析障碍物约束,建立障碍物约束的数学描述;然后,根据穿刺术的要求将穿刺精度、穿刺危险性和穿刺路径长度作为柔性针穿刺优化目标,将柔性针穿刺路径规划问题转化为多目标优化问题;建立了相应的多目标优化问题的数学模型,使用多目标粒子群优化算法对模型进行优化求解.最后通过仿真实验证明了所提方法的有效性,并仿真分析了穿刺路径的在线修正问题.     

涤纶与芳纶及超高分子量聚乙烯纤维复合纱防刺织物的制备及其性能

为降低高性能纤维防刺织物的成本,改善产品的舒适性,通过将芳纶、超高分子量聚乙烯纤维与涤纶进行复合纺纱并制备防刺织物,测试分析了复合纱线基织物以及铺叠层数等对其静态防刺、透气和透湿性能的影响.结果表明:织物穿刺载荷随着面密度的增加而增加,复合纱中引入涤纶可保持或提高织物的防穿刺性能;增加复合纱线织物堆叠层数,织物刺破载荷...     

潮汕脆性肉丸的感官评定与质构评价相关性分析

目的:探索一种综合评价潮汕脆肉丸脆性品质的方法。方法:采用质构剖面法（texture profile analysis,TPA）和穿刺实验测定肉丸的质构特性,同时进行感官评定实验,并对感官和质构指标之间进行相关性分析。结果:TPA实验的硬度、咀嚼性与感官评定指标硬度、弹性、脆性、咀嚼性之间存在显著相关性（r=0.554~0.793,P<0.05）,TPA实验的回复性与感官评定的脆性、组织状态之间存在显著相关性（r=0.556,0.625,P<0.05）。穿刺实验的破裂力与感官评定指标之间均存在显著相关性（r=0.595~0.709,P<0.05）。运用主成分分析从仪器质构指标数据中提取出2个最主要的独立成分,这2个主成分的方差贡献率累计达74.5%。结论:潮汕肉丸的脆性可以采用TPA实验的硬度、咀嚼性和穿刺破裂力的定量评价结合感官评定进行综合评价,为构建客观、精确、便捷的潮汕脆性肉丸感官性状评价体系奠定基础。     

经皮恒河猴肝纤维化模型超声引导下肝脏穿刺介绍

目的:观察超声引导下恒河猴肝穿刺活体组织检查技术在动物实验中的应用情况,探讨超声引导下经皮恒河猴肝脏穿刺活检的价值和意义。方法:采用PHILIPS i U22超声仪、9~3 MHz探头、Bard 16G活检枪及活检针对22只恒河猴肝纤维化疾病进行穿刺,对穿刺组织进行病理检查。结果:22只恒河猴均穿刺成功,病理学染色良好,能够进行肝脏疾病的病理分析和诊断。结论:在动物实验中,超声引导下肝脏穿刺活检术是一项微创、安全、方便的取材方法,能确定肝脏损害的病理性质,对实验动物疾病模型诊断和治疗有重要的临床价值。