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In our screening program for insecticidal activity of the essential oils/extracts derived from some Chinese medicinal herbs and spices, garlic (Allium sativum L.) essential oil was found to possess strong insecticidal activity against overwintering adults of Cacopsylla chinensis Yang et Li (Hemiptera: Psyllidae). The commercial essential oil of A. sativum was analyzed by gas chromatography-mass spectrometry. Sixteen compounds, accounting for 97.44% of the total oil, were identified, and the main components of the essential oil of A. sativum were diallyl trisulfide (50.43%), diallyl disulfide (25.30%), diallyl sulfide (6.25%), diallyl tetrasulfide (4.03%), 1,2-dithiolane (3.12%), allyl methyl disulfide (3.07%), 1,3-dithiane (2.12%), and allyl methyl trisulfide (2.08%). The essential oil of A. sativum possessed contact toxicity against overwintering C. chinensis, with an LC50 value of 1.42 microg per adult. The two main constituent compounds, diallyl trisulfide and diallyl disulfide, exhibited strong acute toxicity against the overwintering C. chinensis, with LC50 values of 0.64 and 11.04 /g per adult, respectively.

Since the features are not prominent and the algorithm is complex during whole reconstruction of section data, a step-by-step optimization reconstruction method is proposed. The order of reconstruction is optimized: line features are reconstructed firstly; Then arc features are reconstructed (constraints are satisfied between the arc and known lines); finally freeform features are reconstructed (constraints are satisfied between the B-spline and known lines/arcs). In this way, the reconstruction accuracy of the line/arc features is ensured in the first. Since freeform features have more freedom, it is convenient to be adjusted to meet the more constraints. Linear boundary constraints are constructed and the algorithm becomes optimization problem of the quadratic objective function under the linear constraints. The examples show that the reconstruction accuracy is improved greatly under satisfying constraints; the expected goal is achieved in real application.

The error of the three-dimensional structure light measurement is analyzed in the paper. The experiment is done to verify the presence of measurement error. The error of data is analyzed and some conclusions are gotten. The three-dimensional structure light measurement is based on the triangulation principle. The error distribution is different because of the view angle of measurement equipment relative to the part to be inspected, the effect of the external environment light and the effect of the data processing software system. Finally, the corresponding compensation measures are put forward in the paper according to different errors.

For the short life of hot work die in enterprise directly caused problems the waste of resources and the rising cost of production. Based on studying the biological prototype of crack-resistance of plant lamina and found that surface thermal fatigue crack is one of the main factors affecting the service life of hot work mould, it is put forward thoughts about the local bionic laser melting on mould surface to block cracks. Different from the traditional mould surface integral laser transformation hardening (LTH) technology, using laser melting simulating plant lamina to block cracks on the partial surface of mold, life of bionic strengthened die is improved within 1~1.5 times. Experiment results show that a new method is provided to improve the service life of casting mould and promoting this technology will bring significant economic benefits for the mould industry.

As there are the errors during the manufacturing and assembling of horizontal driving machine (HDM). The exceptional knocking noise is generated during some products running. The failure rate of product quality is rising as well. The forward and reverse driving noise of HDM was tested and analyzed. The pictures was collected by universal tool microscope. The results show that hot runner is not smooth enough to reduce transferring pressure and increase the shrinkage of worm pouring gate, which lead to slight conical degree of product and pitch deviation at worm pouring gate. As the pitch makes worm inset slightly worm gear when clockwise rotating, the noise and vibration was produced consequently in this direction. The proposals were given, such as strengthening the maintenance of hot runners, controlling and inspecting product conical degree, and optimizing HDM mould and increasing its accuracy, and so on.

The quality of hole is difficult to be guaranteed and tool wears severely in drilling process of the carbon fiber composite material. To investigate the drilling process, a series of drilling experiment has been carried out .The influence law of drilling parameters, including the spindle speed, the feeding speed and the diameter of drill, on the drilling force and drilling quality for the carbon fiber composite material has been investigated.

The failure of the gas valve’s external screw taper thread is a very serious problem which may result in accidents. Routine inspection on the threads is thus necessary. The efficiency of traditional manual testing methods can not meet the production requirements. An automatic visual inspection system for gas valve’s external screw taper thread is presented in the paper. The system consists of a high-performance 200 mega pixels CCD camera, a LED backlight and a holder of gas valve. Through image acquisition, image processing, edge detection and feature dimension measurement, the system can effectively measure the parameters of taper thread such as half of thread angle, depth of thread, taper angle of thread on image domain. Due to the lead angle and installation error, actual half of thread angle is different from the theoretical values. Three methods are presented in the paper for the half of thread angle. Through analysis, Method 3 and Method 2 can be used to measure half of thread angle. The system can meet the testing requirements of the external screw taper thread and has wide application perspective.

Punches and dies are the real operating components and account for a large portion in the progressive die design procedure. This paper presents a structural design tool for punches and dies for progressive dies of motor core based on functional component. The descriptive model of punch and die component is established which contains three aspect of information, geometry information, assembly-related constraint attribute and hole-related information on plates. Based on the classification and 3D modeling method of punches and dies, the library of components for punches and dies is set up according to the descriptive model. Methods for modeling and data management for components of punches and dies are discussed in detail. The proposed tool for progressive die for motor cores can complete the design of five classes of punches and dies and generate holes on plates automatically. This design tool is constructed on a PC and integrated with a SolidWorks CAD system. The progressive die design for the motor core of house appliance is employed as a practical example to demonstrate the effectiveness of the design tool. The results reveal that it can dramatically improve the design quality and can save both time and costs.

Conveying is the important part of product processes, which is significantly affected by product structures. Based on the point of conveying, appropriate design will be result in significant improving conveying performance and reducing the degree of automatic conveying difficulty, then equipment would be simplified, and investment reduced. The design strategies for allover include: reducing the parts quantity and variants, corresponding the part geometry with the conveying manner, and parts geometry convenient for checking and identifying. The methods include two situations: design for conveying in the machining process and design for conveying in the assembly process. Applications of parts design for automatic conveying are illustrated.

The quality of hole is difficult to be guaranteed and tools wear severely in the drilling process of titanium alloy. To investigate more efficient methods to improve the quality of holes, the drilling experiments of titanium alloy Ti6Al4V were carried out under different drilling speed and different feeding speed. The drilling force was achieved through the dynamometers in the experiment. Simultaneously, a series of drilling experiment of titanium alloy was carried out with the two different shape drills and three different diameter drills. The comparison of the achieved drilling force proved that the sharpened tool is better to guarantee the quality of hole for titanium alloy Ti6Al4V.

A combination features based technology is proposed to matching point cloud models. Firstly, automatically segment the point cloud to get ruled shape data from which the statistics features are extracted. Calculate the distance and angle between component elements of statistics feature and datum plane. The distance and angle constraints are introduced to automatically search correspondence statistics features of overlap region and the optimal combination of statistics features. The optimal combination is coupled for combination feature. If combination feature can completely identify pose of model, we call this as completely matching question; otherwise, this is called as partly matching question. For the latter, adjust the degrees of freedom which are not constrained and then precisely match the models using ICP algorithm. The examples show the proposed algorithm is simple and efficient, and the matching results are stable, reliable and convergent to a global optimal solution.

There are a lot of holes in a progressive die for mounting inserts, assembles, and standards. This paper gives the classification of plate holes of progressive die design according to their structural types and relationships between the correlating parts and the plate holes and describes an automated hole design system for progressive dies. Taking advantage of prebuilt design knowledge and standard parts database, this system is able to generate the correlated holes on the main plates of progressive dies, such as upper die shoes, lower die shoes, stripper plates, punch plates, die plates, punch backing plates, and die backing plates according to the inserted parts or functional assembles. A descriptive model is set up. The feature library technology is adopted to develop the function for the design of plate holes, which can improve the efficiency and shorten the design cycle. The hole design system is built on the top of SolidWorks, taking advantage of its built-in modules, including part, assembly, and drawing. We use progressive die for motor core as concrete examples to demonstrate the power of our system. Experimental results show that our system cannot only improve the design quality but also reduce the design time and cost.

It is necessary to smooth point cloud data in reverse engineering or the inspection of free-form surfaces because noisy points will have a negative influence on the post-processing of this data. The big problem in smoothing point cloud data is how to solve the dilemma between removing noisy points and keeping feature boundary information, whilst controlling the diffusiveness of noisy points. In this paper, the theory of anisotropic heat conduction is adopted to establish a mathematical model of point cloud data smoothing. The point cloud data can be considered as a temperature field with an adiabatic boundary. So the heat is only conducted inside the temperature filed and has no effect on the outer side. For point cloud data, it means that the smoothing is only on the local area, which makes a good balance between deleting noisy points and keeping feature boundary information. The method has been implemented by using two cases for practical application, and the result proves its efficiency.

In our screening program for insecticidal activity of the essential oils/extracts derived from some Chinese medicinal herbs and spices, garlic (Allium sativum L.) essential oil was found to possess strong insecticidal activity against overwintering adults of Cacopsylla chinensis Yang et Li (Hemiptera: Psyllidae). The commercial essential oil of A. sativum was analyzed by gas chromatography-mass spectrometry. Sixteen compounds, accounting for 97.44% of the total oil, were identified, and the main components of the essential oil of A. sativum were diallyl trisulfide (50.43%), diallyl disulfide (25.30%), diallyl sulfide (6.25%), diallyl tetrasulfide (4.03%), 1,2-dithiolane (3.12%), allyl methyl disulfide (3.07%), 1,3-dithiane (2.12%), and allyl methyl trisulfide (2.08%). The essential oil of A. sativum possessed contact toxicity against overwintering C. chinensis, with an LC50 value of 1.42 microg per adult. The two main constituent compounds, diallyl trisulfide and diallyl disulfide, exhibited strong acute toxicity against the overwintering C. chinensis, with LC50 values of 0.64 and 11.04 /g per adult, respectively.

The quasi-static compressive and dynamic compressive (SHPB) experiments were carried out to investigate the static and dynamic property of titanium alloy Ti6Al4V though analysis and comparison of the experiment results, the Johnson-Cook constitutive model of titanium alloy Ti6Al4V was established. The cutting process of titanium alloy Ti6Al4V was simulated using the orthogonal cutting finite element model. Though the simulation, the Johnson-Cook model considering the adiabatic effect was more correct. The establishing of Johnson-Cook model provided the conditions for the further simulation and parameters optimization of cutting process of titanium Ti6Al4V.