Automatic feeding mechanism of a vegetable transplanter

An automatic feeding mechanism consisting of a timing shaft,an actuating device and a clutch for feeding paper pot seedlings from a horizontal slat type chain conveyor to a horizontal pusher type chain conveyor of a vegetable transplanter,was developed.The slat type chain conveyor carried the pot seedlings in upright orientation in the form of a rectangular array with each linear array of pot seedlings on a slat.The pusher type chain conveyor received a linear array of pot seedlings and delivered them to the seedling drop tube.Feeding of each linear array of pot seedlings to the pusher type conveyor at appropriate times was done using an automatic feeding mechanism.The laboratory evaluation indicated that the feeding rate of 33 to 50 pot seedlings per minute can be achieved with single set of conveyors.The feeding mechanism also worked effectively under actual field conditions with 98%to 99%of all the pot seedlings,which were properly separated and fed for planting when the forward speed of the vegetable transplanter was 0.9 km/h.The feeding mechanism has the general application of singulating rectangular array of items on the slat type chain conveyor in any industry and machine in motion on a level surface.

Development of Automatic Programming System for NC Laser Cutting of Chinese Characters

This Paper presents an automatic programming system developed for NC laser onning of Chinese charaCterswhich combines AutoCAD with NC Under Windows environment, and generates numerical controlled Programs by extracting outline (stroke) figures of Chinese Characters from outline character base, optimizing cutting routes, transferring them to AutoCAD for editing operations, such as rotation transfer, enlarging an mirroring, the system can transferto a laser cutting machine througy RS-232 series interface to accomplish laser cutting of large Chinese characters.

Evaluation of roof cutting by directionally single cracking technique in automatic roadway formation for thick coal seam mining

Automatic roadway formation by roof cutting is a sustainable nonpillar mining method that has the potential to increase coal recovery,reduce roadway excavation and improve mining safety.In this method,roof cutting is the key process for stress relief,which significantly affects the stability of the formed roadway.This paper presents a directionally single cracking(DSC)technique for roof cutting with considerations of rock properties.The mechanism of the DSC technique was investi-gated by explicit finite element analyses.The DSC technique and roof cutting parameters were evaluated by discrete element simulation and field experiment.On this basis,the optimized DSC technique was tested in the field.The results indicate that the DSC technique could effectively control the blast-induced stress distribution and crack propagation in the roof rock,thus,achieve directionally single cracking on the roadway roof.The DsC technique for roof cutting with optimized parameters could effectively reduce the deformation and improve the stability of the formed roadway.Field engineering application verified the feasibility and effectiveness of the evaluated DSC technique for roof cutting.

Comparative study of model tests on automatically formed roadway and gob-side entry driving in deep coal mines

Automatically formed roadway(AFR)by roof cutting with bolt grouting(RCBG)is a new deep coal mining technology.By using this technology,the broken roadway roof is strengthened,and roof cutting is applied to cut off stress transfer between the roadway and gob to ensure the collapse of the overlying strata.The roadway is automatically formed owing to the broken expansion characteristics of the collapsed strata and mining pressure.Taking the Suncun Coal Mine as the engineering background,the control effect of this new technology on roadways was studied.To compare the law of stress evolution and the surrounding rock control mechanisms between AFR and traditional gob-side entry driving,a comparative study of geomechanical model tests on the above methods was carried out.The results showed that the new technology of AFR by RCBG effectively reduced the stress concentration of the roadway compared with gob-side entry driving.The side abutment pressure peak of the solid coal side was reduced by 24.3%,which showed an obvious pressure-releasing effect.Moreover,the position of the side abutment pressure peak was far from the solid coal side,making it more beneficial for roadway stability.The deformation of AFR surrounding rock was also smaller than the deformation of the gob-side entry driving by the overload test.The former was more beneficial for roadway stability than the latter under higher stress conditions.Field application tests showed that the new technology can effectively control roadway deformation.Moreover,the technology reduced roadway excavation and avoided resource waste caused by reserved coal pillars.

Mathematical modeling and analytical solution for stretching force of automatic feed mechanism

Load of an automatic feed mechanism is composed of the stretching force of feed belt at the entrance to lower flexible guidance and the friction force between feed belt and flexible guidance. A mathematical model for computing the load was presented. An optimization problem was formulated to determine the attitude of the flexible guidance based on the principle that the potential energy stored in the system was the minimum at the equilibrium. Then the friction force was obtained according to the attitude of guide leaves and the moving velocity of the feed belt and the friction factor. Consequently, the load of the automatic feed mechanism can be calculated. Finally, an example was given to compute the load when the horizontal and elevating firing angles of the automation were respectively 45° and 30°. The computing result can be a criterion to determine the designing parameters of automat.

Study on Test Compaction in High-Level Automatic Test Pattern Generation (ATPG) Platform

Advancements in semiconductor technology are making gate-level test generation more challenging. This is because a large amount of detailed structural information must be processed in the search process of automatic test pattern generation (ATPG). In addition, ATPG needs to deal with new defects caused by process variation when IC is shrinking. To reduce the computation effort of ATPG, test generation could be started earlier at higher abstraction level, which is in line with top-down design methodology that has become more popular nowadays. In this research, we employ Chen’s high-level fault model in the high-level ATPG. Besides shorter ATPG time as shown in many previous works, our study showed that high-level ATPG also contributes to test compaction. This is because most of the high-level faults correlate with the gate-level collapsed faults especially at input/output of the modules in a circuit. The high-level ATPG prototype used in our work is mainly composed by constraint-driven test generation engine and fault simulation engine. Experimental result showed that more reduced/compact test set can be generated from the high-level ATPG.

Design and Experimentation of Automatic Tidying and Sorting Mechanism for Blood Collection Needles in Stacking State

Disposable blood collection needles become severely intertwined and hooked during stacking, and thus individually feeding disposable blood collection needles during mechanical packaging is di cult. Based on the physical characteristics of the blood collection needles during the stacking state, this study designed an automatic tidying and sorting mechanism by combining compound vibration, sorting, and conveying. During the feeding process, the compound vibration-type material-tidying mechanism tidies 20-30 blood collection needles first;then, the material sorting and conveying mechanism transports the tidied blood collection needles individually. The orthogonal testing of the automatic material tidying process shows that various experimental factors are ranked by the significance level of the e ect on the tidying process and the significance ranking is as follows: vertical vibration frequency > horizontal amplitude > vertical amplitude > horizontal vibration frequency. Experiments were performed after analyzing the optimal combination. The results demonstrate that when the horizontal vibration frequency is 1.7 Hz, the horizontal amplitude is 150 mm, vertical vibration frequency is 1.3 Hz, vertical amplitude is 30 mm, and material length after tidying is 265 mm. The automatic sorting and conveying experiment shows the e ect of various experimental factors on the feed rate of the material, where the significance level of the e ect is ranked as follows: vibration frequency > material quantity > channel dip angle. The experimental results show that when the number of materials is 25, the channel dip angle is 12°, and vibration frequency is 52.5 Hz. The material delivery e ciency reaches 0.51 s/root, meeting the requirement of five channels for 80000 root/day feeding e ciency. The study can provide reference for the realization of automatic feeding of large aspect ratio flexible materials in similar stacking state.

Endogenous automatic nerve discharge promotes nerve repair: an optimized animal model

Exogenous electrical nerve stimulation has been reported to promote nerve regeneration. Our previous study has suggested that endogenous automatic nerve discharge of the phrenic nerve and intercostal nerve has a positive effect on nerve regeneration at 1 month postoperatively, but a negative effect at 2 months postoperatively, which may be caused by scar compression. In this study, we designed four different rat models to avoid the negative effect from scar compression. The control group received musculocutaneous nerve cut and repair. The other three groups were subjected to side-to-side transfer of either the phrenic(phrenic nerve group), intercostal(intercostal nerve group) or thoracodorsal nerves(thoracic dorsal nerve group), with sural nerve autograft distal to the anastomosis site. Musculocutaneous nerve regeneration was assessed by electrophysiology of the musculocutaneous nerve, muscle tension, muscle wet weight, maximum cross-sectional area of biceps, and myelinated fiber numbers of the proximal and distal ends of the anastomosis site of the musculocutaneous nerve and the middle of the nerve graft. At 1 month postoperatively, compound muscle action potential amplitude of the biceps in the phrenic nerve group and the intercostal nerve group was statistically higher than that in the control group. The myelinated nerve fiber numbers in the distal end of the musculocutaneous nerve and nerve graft anastomosis in the phrenic nerve and the intercostal nerve groups were statistically higher than those in the control and thoracic dorsal nerve groups. The neural degeneration rate in the middle of the nerve graft in the thoracic dorsal nerve group was statistically higher than that in the phrenic nerve and the intercostal nerve groups. At 2 and 3 months postoperatively, no significant difference was detected between the groups in all the assessments. These findings confirm that the phrenic nerve and intercostal nerve have a positive effect on nerve regeneration at the early stage of recovery. This study established an optimized animal model in which suturing the nerve graft to the distal site of the musculocutaneous nerve anastomosis prevented the inhibition of recovery from scar compression.

Accelerating sample preparation of graded thermoelectric materials using an automatic powder feeding system

In recent years,the development of techniques for the controlled preparation of functional graded materials(FGMs)has become a vigorous research field.In this study,to improve the efficiency and accuracy of sample preparations,an automated feeding system based on gravimetric principles for dry powder with three dosing feeders is designed and realized.The feeding rate and accuracy can be regulated by coordinating the protruded length L(mm)and rotational speed V(r/min)of the feeder stirrer.To demonstrate this automatic sample preparation system,the well-known thermoelectric material BixSb2-x-Te3(x=0.3,0.4,0.5,0.6,0.7 and 0.8)is selected and prepared by the developed system,and the composition distribution of the functional graded material is characterized.Experimental results show that the BixSb2_xTe3(x=0.3-0.8)functionally graded material crystalizes in the rhombohedral phase after hot-pressing sintering and annealing and the prepared sample has a good gradient composition distribution.This verifies the reliability and accuracy of the feeding system.The concept of samples with a gradient component and application of the automatic powder feeding system could considerably accelerate the research and development of new materials.

融合复制机制和input-feeding方法的中文自动摘要模型

针对中文自动摘要准确率不高的问题,在含有注意力机制的序列到序列(sequence-to-sequence,seq2seq)基础模型的解码器中融合了复制机制和input-feeding方法,提出了准确率更高的中文自动摘要模型。首先,该模型使用指针网络将出现在源序列中的OOV(out-of-vocabulary)词扩展到固定词典,以实现从源序列复制OOV词到生成序列中;其次,input-feeding方法用于跟踪已生成序列的注意力决定信息以提升模型输出准确率。在NLPCC2018数据集上的实验结果表明,与基础模型相比,所提出模型获得了更高的ROUGE得分,验证了该模型的可行性。

STUDY ON THE CUTTING PROPAGATION TECHNIQUE OF PICEA KORAIENSIS

The cutting propagation technique of Picea koraiensis was carried under automatic spraytng of total sunlight by adopting the same year epicormic branches from different trees with different age treated by different hormones in different concentration and time and the orthogonal and randomized block was designed. The results were as follows : (1)The rooting rate of the cutting reached at least 87 percent, when the cuttings were from the seed tree with the age below 25 years old and the cuts of the cuttings base were in vertical angle and on the fine sand medium. (2) The sequence of effective factors affecting the rooting rate were the style of cut, the age of seed tree and the trpe of mediun. (3) There are significant differences of rooting rate among different clones.

Dynamics analysis on transverse cutting mechanism of straw checkerboard paving robot

The transverse cutting mechanism of the checkerboard paving robot, which directly affects the robot＇s operation, is regarded as the most important part in a transverse pavement system This research aims at designing a new system which is appropriate for desert wofidng en- vironments and finishing cutting the rope of straw. In this paper, computer emulating technology is applied, and with three-dimensional modeling by Pro/ENGINEER software, can observe whether or not interference exists. Also, the speed and displacement parameters of the main parts of the cutting system are given by the dynamic emulation by Automatic Dynamic Analysis of Mechanical System （ADAMS）, which theoretically assures the feasibility and appropriateness of the cutting mechanisrn~ Finally, results of the experinaent shows that the cutting mechanism can cut the straw strand as designed.

Research on the memory cutting path of shearer based on genetic algorithm

In order to realize the memory cutting of a shearer, made use of the memorizedcutting path and acquisitioned cutting parameters, and realized the teaching and playbackof the cutting path.In order to optimize the memory cutting path of a shearer, took intoaccount the constraints of coal mining craft, coal quality and the adaption faculty of coalmining equipments.Genetic algorithm theory was used to optimize the memory cutting ofshearer and simulate with Matlab, and realized the most valuable mining recovery rate.The experimental results show that the optimization of the memory cutting path of ashearer based on the genetic algorithm is feasible and obtains the most valuable memorycutting path, improving the ability of shearer automatic cutting.

Automation of choice of instrumental equipment and study of thermo-stressed conditions of metal-cutting instrument

This article about possibility of automations of choice of instrumental equipment. In it described problems of choice of equipment, which are decided by means of mathematical model, developed on the base of finite element method.

数字孪生驱动的巷道自动成形截割虚拟调试方法研究

针对目前巷道自动成形截割控制调试周期长、调试成本大、安全风险大、成形质量难以评价等问题,提出了一种数字孪生驱动的巷道自动成形截割虚拟调试方法。采用基于即时外观建图(RTAP−MAP)技术重建巷道三维环境,构建掘进机控制系统模型,形成虚拟调试环境,并利用虚拟传感器技术实现物理空间到虚拟环境状态的精准映射。针对难以量化评估断面成形质量的问题,确立了巷道自动成形截割性能评价方法,以断面成形截割控制过程在数据传输中心的记录为基础,主要对断面成形精度、截割效率与油缸开关次数、硬岩切割调整、超挖欠挖4个评价指标进行计算,从而为深度学习算法的迭代优化提供精准反馈信号,并提出了一种融合强化学习的自动截割控制策略,以提高自动化作业的适应性和精确度。为验证该虚拟调试方法的有效性和准确性,搭建了掘进机自动控制实验平台,并将虚拟调试系统应用于掘进巷道成形截割自动控制程序中。虚拟仿真结果表明:①被调试软件在控制关键点位处的X,Y,Z轴定位误差的最大值分别为74.8,72.93,123.67 mm,说明虚拟调试方法的定位精度达到性能要求。②虚拟样机与物理样机轨迹基本一致,说明该调试方法实现了对物理空间的映射。应用结果表明:①强化学习控制器在虚拟掘进测试中适应了复杂环境,将虚拟传感器输入有效转换为精准控制指令,验证了模拟−现实迁移训练的可行性。通过处理掘进精度和避免超欠挖的实时反馈,控制器学习并优化了策略。②优化后的断面成形截割控制性能得到了提升,根据数据库中控制量时间戳的记录,用时126 s,较优化前耗时减少了8 s。③优化后截割部末端轨迹跟踪最大误差为6.0 mm,较优化前降低了0.3 mm,避免了截割轨迹抖动导致的欠挖,同时使得轨迹和断面更加平滑。

现场混装乳化基质自动加料系统的研究开发

为解决传统工艺中给现场混装车加注乳化基质效率低、现场人员多等问题,研究开发了自动加料系统。采用二维码视频识别和图像处理技术进行混装车的准确定位,并对基质储罐下料口和混装车加料口的对准情况进行自动提示;自动加料控制模块实现了自动、定量加料和现场/远程操作与控制,并且能够防止飞溅和溢出,乳化基质的加注量等信息,由系统自动记录和管理,达到了混装车乳化基质加料过程的智能化和少人化目标。该系统在炸药厂运行了近3年时间,共加注现场混装乳化基质近12 000 t,通过加料数据的实时反馈,还实现了生产任务制定、车辆调度等的精细化管理。应用结果表明,开发的自动加料系统不仅实现了乳化基质加料过程的智能化,还对提升我国现场混装乳化炸药全工序智能化水平有促进作用。

蔬菜钵苗自动移栽机纵向送盘机构设计与试验

为进一步提高蔬菜钵苗自动移栽机纵向送盘机构的精确性与稳定性,提出一种由凸轮连杆与扇形齿轮驱动的四连杆纵向送盘机构。首先,通过分析纵向送盘工作过程,确定机构设计要求与整体方案,规划理想的纵向送盘轨迹,建立了纵向送盘机构轨迹综合模型,并利用遗传算法进行了初步求解。然后,基于Matlab GUI开发了纵向送盘机构可视化计算机辅助优化分析软件,获得满足设计要求的纵向送盘机构设计参数。最后,对纵向送盘机构进行了结构设计、仿真分析和试验验证,结果表明:试验实际轨迹与理论、仿真轨迹基本一致;移栽效率为80、90株/(min·行)时,机构单次送盘误差均在±1.5 mm以内,且多次送盘后没有出现累积误差,同时通过取苗试验观察发现纵向送盘机构与取苗机构配合良好,验证了机构设计的合理性。

瓶栽鹿茸菇自动采收装置设计与试验

针对瓶栽鹿茸菇工厂化采收装备缺失的问题,提出了一种“输-定-切-夹”采收工艺,并设计了相应的自动采收装置,阐述了装置总体结构及工作原理,确定了整机作业流程。通过对栽培筐输送过程运动学与力学分析,确定了导流条安装角及输送辊筒参数;基于ANSYS LS-DYNA对切割过程进行了仿真分析,以切割速度、进给速度、带锯条前角及齿距为试验因素,以切割反作用力为响应指标,通过响应面法进行了切割性能建模和优化。结合物理试验确定了最优参数组合:切割速度为6.49 m/min、进给速度为0.12 m/min、前角为25°、齿距为7 mm;采用ABAQUS软件对柔性手指弯曲过程进行了仿真,结合物理试验确定了柔性手指最优结构参数为:气腔厚度2 mm、气腔7个、气压25 kPa、限制层厚度3 mm。整机试验表明,装置运行平稳,采收作业效果良好,平均采净率、平均损失率和平均损伤率分别为98.18%、3.66%和2.75%,满足瓶栽鹿茸菇实际采收要求。

基于单片机控制的异形件双轨供料装置的设计

在电子电路板制造行业,部分非标异性元件需要人工完成供料工序,再对接快速贴片机(Surface Mount Technology,SMT)完成整个生产工序,效率低下,无法满足电子产品组装行业的发展需求。为此设计了一种基于单片机控制的散料异形件供料器,包括2套振动装置和直线导轨,振动装置呈螺旋形上升与直线轨道连接,2个直线导轨并行工作,直线振动器可使导轨部件振动使导槽内的散料移动,当散料移动至导槽的末端时,插件机吸夹嘴定点取料从而进行自动贴插件。与传统的手工贴插件相比,散料经本装置供料后,自动贴装品质更加得到保证。实践结果表明,该装置兼容现有的SMT设备及插件机设备,实现了供料器的全自动工作,提高了生产效率;所需员工从5人减少至1人,生产节拍从5 s/件降低至1 s/件,次品率从3‰大幅度下降至1‰。

基于OBE理念的林业“自动控制原理”实践教学改革探索

基于OBE理念,从林业领域对新工科工程技术人员的具体特色需求出发,遵从“电类”专业实践教学培养方案及毕业要求,以“自动控制原理”实验课程为例,以问题为抓手,以成果为导向,探索基于OBE理念的“自动控制原理”实践教学目标,改革实践教学内容及教学方法,建立合理的考核评价体系,通过科研反哺教学,建立基于林业科研项目的案例库,并应用于“自动控制原理”实践教学,促使专业承担起人才培养的任务和基础,为林业生态发展提供高素质的“电类”工程技术人员。