基于Rhino-Python的多圈高簇绒地毯三维仿真

为解决空间结构复杂的多圈高簇绒地毯在实现其外观三维仿真时缺乏真实感的问题,利用Rhino环境下的PythonScript实现了簇绒地毯外观的三维仿真。将绒圈中心线及截面曲线分段后局部求解相关控制点坐标,再由B样条曲线对二者进行拟合。同时考虑到地毯绒圈之间的相互挤压导致绒圈发生了随机偏转变形,通过设计算法模拟了绒圈产生形变后的状态。在此基础上添加绒圈表面纹理及光照模型,进一步渲染输出仿真结果。测试结果表明:利用B样条曲线拟合原理并借助于Rhino-Python平台的簇绒地毯三维仿真方法是可行的,且易于实现;与实际地毯样品相比,能够较为真实地模拟不同排纱规律下多种花型图案、绒圈高度变化的簇绒地毯。     

基于滤波最小均方算法的簇绒地毯装备噪声主动控制

为降低纺织车间簇绒地毯装备的低频噪声,将噪声主动控制的滤波最小均方算法 (FXLMS)引入纺织机械噪声控制领域。以英国柯贝尔 1/8针距簇绒地毯织机为研究对象,建立了噪声主动控制系统模型,根据现场情况布置传感-作动单元;并运用双传声器离线通道辨识方法估计初级和次级通道传递函数;针对前馈控制策略引起的次级声反馈现象,选用参量阵扬声器作为次级声源减轻该现象对噪声控制系统稳定性的影响。最后对簇绒地毯织机噪声的主动控制仿真研究和实验验证了该方法的可行性和有效性。实验结果表明:簇绒地毯织机采用的主动噪声控制方法对低频段噪声的控制效果较中高频段好,簇绒地毯织机噪声主要频率点的噪声消声量最大可达9.8 dB。     

地毯簇绒机簇绒针传动机构运动分析

 地毯簇绒过程中簇绒针的力学和运动性能制约了主轴转速的提高,影响着整个机械系统的振动特性,而簇绒针的运动性能直接取决于传动机构的设计。根据地毯簇绒运动的工作原理,设计了由曲柄摇杆机构和曲柄滑块机构组合而成的簇绒针传动机构,并对传动连杆机构的运动进行了数学分析;应用ADAMS仿真软件对不同曲柄参数条件下的传动机构进行运动分析和比较,着重对簇绒针刺入底基布时的运动和受力状况进行讨论,确定了曲柄的最优设计值。分析结果已应用到DHT-200地毯簇绒机的设计实践中。     

基于非简谐方式的地毯簇绒机成圈运动的时间配合

针对地毯簇绒机成圈运动的时间配合关系与簇绒工艺要求之间不匹配会影响地毯质量的问题,首先提出地毯簇绒过程中时间配合的分析要点,以指导成圈机构的结构设计和相位关系的确定。通过Adams运动分析,获得传统成圈运动机构的时间配合关系,指出该时间配合关系的不足之处,由此提出2种基于非简谐运动方式的成圈运动机构的时间配合方法,并进行了相应的执行机构设计。经过Adams运动分析验证该成圈运动机构可较好地满足地毯簇绒工艺要求。     

簇绒地毯织造工艺的探讨

本文从簇绒地毯的生产原理开始,详细分析了簇绒地毯组织结构和工艺设计,并进一步探讨了簇绒地毯的生产织造的方法以及主要的后整理等工艺。     

机制簇绒地毯质量特性的综合优化

为研究机制簇绒腈纶地毯的质量特性,采用加权主成分分析(WPCA)与稳健设计理念相结合的方法,优化利用M-tuft高科技设备生产的簇绒腈纶地毯的质量和生产率。结果表明,压缩标准越低,压缩回弹率和毛束联结牢度的标准越高,生产的地毯质量也越好。为提高质量和生产力,评估了机制簇绒腈纶地毯生产的最佳工艺环境,并进行了参数设置优化。     

基于统计能量分析的簇绒地毯织机高频噪声抑制

为有效抑制簇绒地毯织机高频噪声,提出了基于统计能量分析(SEA)的簇绒地毯织机高频噪声降噪方法,并运用三聚氰胺多孔吸声材料实现了高频噪声的抑制。首先建立了包含13个结构子系统和10个声腔的簇绒地毯织机高频噪声SEA模型,随后采用理论计算方法确定了各子系统的模态密度、内损耗因子以及耦合损耗因子。实验测量了簇绒地毯织机工作时振动加速度信号从而获取SEA模型高频噪声声压级,并通过与簇绒地毯织机工作时实际声压级情况对比验证了SEA模型的有效性。最后在簇绒地毯织机表面粘附了不同厚度的三聚氰胺多孔吸声泡沫板实现降噪。结果表明:该方法能够满足工程上对簇绒地毯织机高频噪声抑制的要求,且噪声频率和三聚氰胺多孔吸声材料的厚度均对结果有影响。     

Sellers Engineers

随着亚洲地毯贸易的兴起,预计在 ITMA Asia 上的参观者中有相当一部分人是地毯制造技术的潜在投资者。Sell- ers Engineers 公司在主要地毯生产方式方面的后整理机械位居世界之首,主要的生产方式有簇绒、机织、针刺。该     

地毯簇绒系统纱线张力建模与分析

为提高簇绒地毯分辨率,提升地毯的品质,建立正确的纱线张力模型是精确控制地毯绒高的关键。首先介绍了簇绒装备系统的组成及纱线的导向路径,然后将米纳科夫的拓展欧拉公式引入纱线张力系统,考虑纱线束为黏弹性负载,分阶段对张力系统进行建模。其中,纱线张力系统模型包括提花罗拉、恒张力导纱罗拉和多层导纱器。通过对比仿真与实验所得的纱线张力变化曲线,验证了模型的准确性,为下一步张力控制器的设计提供了参考。     

簇绒地毯的连续染色

在世界地毯产量中簇绒地毯占绝大部分。1985年预报地毯总产量为2383百万平方米,其中四分之三为簇绒地毯,产量为1798百万平方米。 约80％的簇绒地毯产量集中在北美和西欧。在美国,有90％以上的地毯是簇绒的。簇绒地毯的绒毛纤维大多为聚酰胺,约占75％。     

负离子地毯的功能性及负离子素的配比优化

采用共混法将负离子素超微粉体镶嵌于纤维之中，制成丙纶BCF丝，然后经织造、采用负离子浆进行背涂，生产负离子健康地毯。采用正交试验优化负离子素的配比为：负离子素的粒度至少应在单纤直径的1／3以下；添加量为母粒的30％以上；纺丝油剂应比通常用量提高1．5％左右。使用负离子健康地毯．可净化室内空气、抑菌防臭、提高组织供氧、改善新陈代谢、增强人体免疫力。     

平割平圈地毯织机的工艺时序分析与设计

针对我国地毯织造技术基础研究相对薄弱的现状,为给平割平圈地毯织机设计提供更多的理论指导,首先参考时间圆图设计方法和一般割绒地毯织机的工艺要求,提出平割平圈地毯织机簇绒针和成圈钩组件的运动时序关系。然后通过对连续圈绒、割绒和圈割绒交替簇绒时的成圈工艺分析,指出成圈绒时簧片的动作稍超前于成圈钩的远止点时刻,成割绒时簧片动作最晚时刻在成圈钩的远止点时刻,得出平割平圈地毯织机的运动时序关系图。由于平割平圈地毯织机的簧片运动由电气控制实现,独立于由主轴驱动的针、钩、刀的运动体系,因此,运动时序的分析和设计可为成圈机构的机械设计、电气控制系统的设计提供理论参考。     

维吾尔族地毯图案数字化技术

 针对织物图案CAD中需要保存和传承民族的风格特点,以维吾尔族的恰其曼地毯设计为实例,提出一种研究织物图案的CAD方案。首先,通过标识地毯图案元素,利用模板匹配算法提取图案中的同类元素,构成不同类别的图案基因库;然后引入PhotoShop中的路径、画笔预设技术,实现组合PhotoShop技术的织物图案风格化设计。该方法真实地引入了民族地毯的风格设计元素,可以设计出具有民族特色的维吾尔族地毯图案     

The design and initial evaluation of visual cues in carpets to assist walking

Prior research has shown that carpets assist walking thereby reducing the incidence and injury severity of falls, and that visual cues can assist walking. However, little attention has been given to the ability of visual cues in carpets to assist walking. Design guidelines were developed for the colouring and patterning of carpet to provide visual cues to assist walking. The guidelines took into account age-related visual impairments, and were applied in the preparation of a carpet. The designed carpet was compared with two carpets of standard designs in an impaired walking trial. The trial subjects reported a significant preference for walking on the designed carpet, suggesting that appropriate design of carpets can increase their contribution to the well-being of older people and others with impaired walking.     

Evaluation of the pinpoint effect on carpet appearance

In this article, a novel method for evaluating the pinpoint effect of pile yarns of carpet is introduced. The method was initially accomplished by presenting a standard method for bundle preparation. Afterward the changes in free spaces between yarns in bundle cross section introduced as an index for evaluation of the degree of pinpoint effect of heat-set yarns on carpet appearance. To achieve the objectives of this research, yarns of different twist were heat set at various times and temperatures. The ratio of free space between yarns to the total area of the bundle was obtained using image processing technique and defined as the index of pinpoint effect. Taguchi method of experiments design was applied to investigate the effect of the mentioned controllable factors of heat-setting process on pinpoint effect of pile yarns of carpet. The results established that increasing the twist, time, and temperature positively contributes on pinpoint effect. Higher twists, times, and temperatures create a jam structure resulting in higher packing density of the yarn and better pinpoint effect. The results of objective method are in good agreement with those of subjective method. Consequently, the objective method of calculating the pinpoint effect can be used as a reliable method to evaluate the pinpoint effect of pile yarns on carpet appearance.     

Study on thickness loss of cut-pile carpet produced with heat process modified polyester pile yarn. Part II: dynamic loading

Thickness loss (TL) is one of the most important mechanical properties in each carpet. In this research, four types of ATY polyester pile yarns were used to prepare the cut-pile carpet samples. They were normal ATY polyester filament pile yarns and three yarns that modified by heat processes including friezing, heat setting, and twist heat setting. Woven carpet samples are subjected to standard dynamic loading test. Results show that friezing and heat setting processes have no significant effects on carpet dynamic recovery or TL after dynamic loading. Also, decreasing temperature of twist heat setting, the polyester pile yarns could not modify carpet TL after dynamic loading.     

节能环保型航空地毯的开发研制

文章针对目前航空地毯发展的迫切需求,开发了超轻阻燃、节能环保型的航空地毯。本文主要介绍了原材料的选用要求及纺纱工艺的控制,染色过程中阻燃剂及助剂的控制技术要点,织造工艺中绒高与密度参数的研究设计,后整理技术中新型胶乳与背胶工艺配方的应用研究及上胶工艺参数的控制。     

Logistics of carpet recycling in the U.S.: designing the collection network

Efficient collection of post-consumer carpet is an important part of the carpet recycling process that helps to reduce the cost of recycled materials as well as provide sufficient volumes of carpet for recycling facilities. This paper focuses on the design of a collection network for carpet in the U.S. The location set covering optimization model formulated in the paper allows locating the minimum number of collection centers throughout the U.S. to reach a specific level of population coverage and as a result, a target collection rate. To solve real-scale instances of the problem, a novel randomized greedy heuristic is developed. The heuristic is shown to perform better than existing greedy heuristics in the literature. In addition, the paper presents the resulting nationwide carpet collection networks for different levels of population coverage. The results of the study can be used for U.S. carpet recycling policy-making decisions.     

The Dynamic Mechanical Response of Carpets: An Alternative Measurement Technique

The dynamic-compression properties of carpet are expected to play an important role in their mechanical performance, but it is difficult to measure these properties at frequencies and pressures corresponding to those occurring in carpet wear. A new vibration technique has been developed which enables the dynamic modulus and damping loss of a carpet lo be measured at pressures comparable to these imposed in carpet wear. The technique involves supporting a vibrator on a soft spring and allowing it to activate a pressure plate resting on the carpet. The results obtained are in agreement with previously published data but relate to a pressure range which is more relevant to carpet wear. Measurements are made at a static pressure of 22 kPa, a dynamic pressure of 1 kPa, and frequencies in the range 200–600 Hz.