Human-centric design personalization of 3D glasses frame in markerless augmented reality

This paper presents a virtual try-on system based on augmented reality for design personalization of facial accessory products. The system offers several novel functions that support real-time evaluation and modification of eyeglasses frame. 3D glasses model is embedded within video stream of the person who is wearing the glasses. Machine learning algorithms are developed for instantaneous tracking of facial features without use of markers. The tracking result enables continuously positioning of the glasses model on the user’s face while it is moving during the try-on process. In addition to color and texture, the user can instantly modify the glasses shape through simple semantic parameters. These functions not only facilitate evaluating products highly interactive with human users, but also engage them in the design process. This work has thus implemented the concept of human-centric design personalization.     

热轧锭杆“黑心”问题的探讨

锭杆是纺机中一种数量大、转速高、尖端要求耐磨的杆状零件。用热轧方法生产的锭杆毛坯,在其纵、横截面上经酸蚀后出现了“黑心”问题。本文通过一系列试验和观察证实“黑心”并非疏松,“黑心”的存在也不影响耐磨性。从而否定了由于“黑心”是疏松而需将现行热轧方法改用车削方法生产锭杆毛坯的论点。本章对“黑心”形成的原因作了分析和探讨,认为“黑心”是由于斜轧时各部分变形不均匀,而使不同区域里纤维状组织的纤维变形形式不同所致。     

The development of a high-speed spindle measurement system using a laser diode and a quadrants sensor

Reducing the manufacturing time is the trend of precision manufacturing, and the precision of a work-piece is very important for manufacturing industry. High-speed cutting is becoming more widely used and the high-speed spindle is a very important element, whose precision may affect the overall performance of high-speed cutting. Most of the studies on high-speed cutting are focused on the cutting force, the vibration of the spindle and the effects of the spindle's thermal expansion; however, the measurement of the high-speed spindle continues to use the conventional spindle measurement method.As with the measurement of the high-speed spindle, more strict demands are set on the dynamic balance of cutting tools and the bandwidth of the measurement systems when compared with common spindles. The capacitance displacement sensor has been employed for the spindle error test. The precision of the measurement system is limited by the reference (such as a master ball or a master cylinder). Also the capacitance sensor and the reference must be grounded together. This paper presents a simple spindle measurement system using a laser diode and a quadrants sensor, with accuracy up to 1 μm, within 300,000 rpm for various spindles. The system does not need any reference and it is easy to set up. This system can be applied to measure the spindle errors, the spindle speed and the spindle indexing.     

数控机床主轴位置自动测量的实现

论述了数控机床主轴的结构以及数控机床主轴位王的测量电路的设计，实现了数控机床主轴位王参数的自动化测量过程。     

Novel methods for rapid assessment of tool performance in milling

The paper examines the effectiveness of two innovative techniques designed to rapidly optimize a milling application. One of them relates to quantifying the relative wear of different insert grades concurrently in a single cutting test, by mounting the inserts in the same cutter, for a quick comparative performance evaluation. Experimental results that illustrate the validity and limitation of this concept, and a scheme for enhancing the reliability of the test method are presented. The other technique refers to rapid identification of the optimum feed/tooth that corresponds to maximum tool life. This entails a test wherein individual inserts in the cutter are subject to feed/tooth that are multiples of a base value, by selectively leaving appropriate number of consecutive insert pockets unoccupied. These novel techniques complement known accelerated tool life tests, and are expedient for industries that engage short production runs, in terms of selecting a suitable insert grade for an application, and determining optimal cutting conditions for the selected grade.     

数控机床主轴部件变形的有限元分析

利用有限元分析方法进行优化设计,在产品设计阶段就能对主轴部件静、动态特性作出符合实际的预测,使数控机床主轴部件实现优化设计,进而提高产品一次设计成功率、缩短产品开发周期,提高数控机床产品的设计水平.     

应用有限元方法对高速电主轴的优化设计

介绍了高速电主轴的结构特点，应用有限元分析软件ANSYS以刚度为目标对高速电主轴进行了优化设计，并对优化后的结构进行了热态校核。     

CA6140机床主轴有限元分析

在机械加工中，CA6140机床的主轴在转动情况下，变形十分复杂，是造成工件尺寸误差和形状误差的主要原因之一，论文通过建立CA6140机床主轴的几何模型，采用有限元分析方法，分析了机床主轴在加工过程中的变形和应力，依据有限元分析结果，提出了减小机床加工误差的方法。     

车铣加工中心刀塔结构的动力学建模

由于车铣加工中心刀塔结构的复杂性和多结合面性，本文将其分解为四个子系统，结合面用等效弹簧和等效阻尼代替，利用一个柔性结合点可以用二个刚性结合点和一个子结构替换的原理，并运用机械阻抗凝聚法和子结构综合法建立了刀塔结构的动力学模型。     

An experimental investigation into soft-pad grinding of wire-sawn silicon wafers

Silicon is the primary semiconductor material used to fabricate microchips. A series of processes are required to manufacture high-quality silicon wafers. Surface grinding is one of the processes used to flatten wire-sawn wafers. A major issue in grinding of wire-sawn wafers is reduction and elimination of wire-sawing induced waviness. Results of finite element analysis have shown that soft-pad grinding is very effective in reducing the waviness. This paper presents an experimental investigation into soft-pad grinding of wire-sawn silicon wafers. Wire-sawn wafers from a same silicon ingot were used for the study to ensure that these wafers have similar waviness. These wafers were ground using two different soft pads. As a comparison, some wafers were also ground on a rigid chuck. Effectiveness of soft-pad grinding in removing waviness has been clearly demonstrated.