公路划线机的应用现状和发展方向.doc

公路划线机的应用现状和发展方向刘湘晨 薛 龙 戴静君(北京石油化工学院机械工程系，北京10261 7)摘 要： 论述了国际、国内公路划线机在推广使用过程中存在的主要问题和产生的原因，并研究了从多方面进行改进的可行性。这些措施是：提高喷漆压力，使涂料能很快地渗入地层内，加强与地面的附着性能；采用计算机位置控制技术与光电图像识别技术组成划线机的控制系统，使划线机在作业时能根据路面情况，自动确定喷头的最佳喷划位置，实现智能化自动跟踪划线作业。关 键 词:公路划线机；道路养护； 自动跟踪中图法分类号 U41552公路划线机是用来在高等级公路及城市道路上划各种路面标线的专用机械。在道路的养护过程中也用于在旧标线上划新标线。随着我国经济的高速发展，公路增长极为迅速，由此，公路车道的划线工作十分繁重。目前，国内普遍采用人工划线，工作速度慢，劳动强度大，已不能满足当前形势发展的需要。所以，道路划线机是高等级公路养护机械中急需开发的产品之一。目前，国外采用普通型和热熔型两种类型的划线机较多。热熔型道路标线划线机用来涂刷热熔型反光涂料，具有涂料与路面粘结力强、定向反光效果好、耐磨、抗老化、干燥迅速、流动性好等优点 。但由于此种结构材料对所使用的线机技术要求高，至今我国只有个别地区引进此类机械，尚无理想的国产机型。普通型道路标线划线机卣于原料来源充足，且售价低廉，使用和运输方便，对划线机的功能要求相对简单，因此在国内公路养护特别是城市道路养护中占主要地位。1、划线机的种类及其特点:路面标线主要有连续线和间断线两种，划间断线对机器的可控制性要求较高。划线所用的材料有普通的常温油漆(冷漆)、加热油漆，现发展到热熔油漆和熔融塑料(热塑性塑料)。在使用热漆和熔融塑料时，可预先加入反光玻璃微珠，从而提高了雨雾天气和夜间的能见度。此外，还有一种粘胶条线，事先制好特殊字符或数码，使用时在粘贴处喷洒粘接剂后贴上即可。11 划线机按行走方式分类:划线机按行走方式可分为：手扶式、自行式、车载式。手扶式，一般又分两种形式，一种需靠人力推动及控制行驶和划线方向；另一种有发动机作为行驶动力，而人仅控制行驶和划线方向。主要适用于城区、特种图形、走向复杂的划线工作 。自行式有专用底盘和通用底盘两种。配有简单的运行机构和动力装置。工作时一般由驾驶员和操作员分别操作。其功率及容量较大，且行驶速度和划线速度均较快，可用于大范围的划线工作。车载式的特点是所有划线设备均设置在一辆大型卡车的底盘上，故储料箱容量比自行式更大，转移迅速，适用于工地离基地较远的情况。12 按所使用的喷涂材料分类:按所使用的喷涂材料可分为冷漆划线机和热塑划线机。冷漆划线机具有低压有气喷涂和高压无气喷涂两种冷喷装置。低压有气喷涂由喷涂罐、稀释剂罐、管道和冷喷式喷枪组成。工作时涂料被015 03 MPa的低压空气挤压沿输送至喷枪，在喷嘴口处产生膨胀形成第一次雾化。雾化后的涂料液流在喷枪出口处被07MPa的高压雾化空气猛烈地喷出形成第二次雾化 。雾化后的涂料经喷嘴喷出后与地面之间产生机械粘合作用，形成标线涂层。其特点是：(1)雾化细腻，但存在空气反弹，喷出的涂料有飞溅，产生所谓的“毛边”现象；(2)可喷涂料的粘度低，施工时要加入较多溶剂；(3)流量小，不易获得较厚的涂层(漆膜厚度小于03 ram)，标线缺乏力度感；(4)涂层质量受到来自雾化空气中水份、油份的影响。无气喷涂式划线机是利用专用高压泵对漆施加1015 MPa的压力，然后通过喷枪喷涂于地面，高压泵的加压方式有柱塞式和隔膜式2种。此种设备所喷涂出的标线整齐、美观，由于压力较大，不受涂料漆粘度的影响，无需稀释溶剂，因此喷涂出的标线较厚且均匀，故使用较为广泛。热塑划线机是将热熔油漆或热熔塑料在热熔罐中加热至使用温度(一般为180200 C)。其划线方式一般有刮涂式、挤压式、喷涂式3种。其中喷涂式类似于冷漆划线机；刮涂式则是通过10 cm 宽的硬质刮涂板来划线；而挤压式则足通过可调节宽度的挤压器来划线的。热喷枪在整体结构上与冷喷枪不同，它周围被高温循环导热油包围，雾化高压空气事先被加热，这样保持了热熔涂料在整个工作过程中的较高温度。其特点是：(1)划出的标线鲜明、整齐饱满、有力度，涂料厚且均匀，耐磨性好，寿命较高压无气喷涂长23倍；(2)存在空气反弹，故涂料飞散严重，划出的标线有毛边；(3)附着力差，最好用高压无气冷喷装置先喷一层底料，增大附着力；(4)标线缺少一定的表面粗糙度，若遇地面有水，易引起车辆打滑；(5)工艺造价高，对路况要求较高，最好用于新路面。2、 划线机在使用中存在的关键问题和发展方向:虽然已有的划线机种类繁多，但仍有一些尚未解决的问题影响其推广和使用。分析问题产生的原因，以下因素是关键：(1)喷漆压力不够，影响了划线质量。国内已有的划线机喷漆压力一般为6 MPa左右，漆膜厚度为02 mm。实际使用证明，喷划后的道路标线使用期通常为24个月左右线迹就开始剥落。这主要是由于喷漆压力较低，导致漆膜较薄，能很快地渗入地层内，与地面的附着性能差。应从选用新型高压泵人手，提高喷漆压力(国外已达到20 MPa)，保证划线质量。(2)喷射部件使用不恰当。各种类型的喷嘴均有最佳喷射距离或喷射角度范围。距离过高，会使喷嘴角度增加，线宽增大，线条不清晰，且漆膜厚度减小；距离过低，喷射角度减小，漆膜厚度增加，干燥时间延长，且易产生“毛刺”、“流漆”现象。所以，选择的喷嘴应与漆料的性能相一致，并布置在适当位置，以符合喷嘴工作范围的要求。(3)划线机控制系统设计不完善。现有的划线机在划直线时尚且很容易出现走偏、不整齐等现象；在弯道半径较小时也无法进行划线作业；尤其是不能实现重复旧线的功能。总是需要人工每划一段线进行一次调整，工作效率和劳动强度可想而知。这些情况的产生主要是因为控制机构功能不完善所至。因此，使用基于图像识别技术的计算机自动检测与随动位置跟踪技术，将大大提高划线效率。该系统由CCD黑白摄像头、图像采集卡、微型计算机或单片机、随动位置跟踪系统、控制软件等组成 。在划线作业时，一般预先按设计标准打好点，确定标线的位置和划线机行驶的线路。根据打的点，分段拉线，连续作业。所以，对预设拉线的精确跟踪是保证划线作业质量的关键。可以采用基于视觉传感器的拉线跟踪控制系统，由视觉传感器CCD直接拍摄路面与拉线或原旧标线的黑白图像，通过Marr边缘算子图像处理方法准确提取其位置信息 。涂料喷枪运动的伺服控制可采用自调整模糊控制器来实现，在不知道控制对象精确数学模型的情况下，通过检测拉线或原旧标线的跟踪偏差进行模糊推理，作出最优控制决策。经过以上技术改进后，可以将摄像头安装在划线机喷头的前方，当划线机沿预设拉线或原旧标线运行时，经过摄像头的视场区，摄像头便会摄取其走向图像送至计算机进行处理。使划线机在作业时能根据外部情况，自动确定喷头的喷划位置，实现自动轨迹跟踪划线作业。参考文献:1.宋永刚，郭蕴青道路标线划线机的几个关键技术EJ筑路机械与施工机械化，1997(3)：22232.屈耀庭道路交通标线质量和划线机的选择JApplication and Trend of筑路机械与施工机械化，1997(1)：23243.陈同初引进TS290TE型划线机提高热熔反光标线的施工质量J辽宁交通科技，1996(4)：35364.周耀天，魏春景HFMANNH81小型手扶式划线机J筑路机械与施工机械化，1997(1)：16185.沈松云国外划线机J建筑机械，1998(10)：38 396.董大为TRASSARTS280P型白行式划线机J筑路机械与施工机械化，1998(1)：13157.张晓春，刘岩基于计算机图像识别的表面裂纹检测方法J重型机械2003(5)：9118.高向东，黄石生基于视觉传感的焊缝跟踪控制系Application and Trend of Highwaylineation MachineLiu Xiangcheng Xue Long Dai Jingjun(Department of Mechanical Engineering，Beijing Institute of Petrochemic al Technology，Beijing 102617)Abstract This paper introduces the main problems of highwaylineation machine in application at home and abroad and the corresponding cause sand studies the feasibilities of innovation The following measures could be taken：(1)Raise the painting pressure to make the material quickly penetrate into the layer of earth and improve its adhesive performance to the ground； (2) Integrate computerlocation technology with photo electivity imagerecognition technology to control the lineation machine，enabling the lineation machine to automatically fix the best position for lineation based on the surface conditions in operation，thus realizing intelligent automatic lineationKey words highwaylineation machine；highway maintenance；automatic lineationHighwaylineation machine is used in highway and urban road planning a variety of special pavement marking machine. In the road maintenance process is also used in the old standard online planning new marking. As Chinas rapid economic development, road growth is extremely rapid, thus, road lane marking work is very heavy. Currently, commonly used artificial crossed the domestic, work is slow, labor intensive, and can not meet the development needs of the current situation. Therefore, the road marking machine is needed for highway maintenance machinery in the development of products. At present, foreign countries the ordinary type and two types of hot melt marking machine more. Hot melt marking machine road marking thermoplastic reflective coating is used to brush with paint and surface bonding ability, effective directional reflectors, wear, aging, drying quickly, the advantages of good mobility. However, such a structural material of the wire used in machines for high, only individual regions of China since the introduction of such machinery, there is no ideal domestic models. Ordinary road marking line machine wine container in adequate sources of raw materials and low price, easy to use and transport, the functional requirements of the line machine is relatively straightforward, road maintenance in the country especially in urban road maintenance in the dominant. 1、Line machine types and their characteristics: Pavement markings are mainly two continuous line and discontinuous lines, designated continuous line on the machine can be controlled demanding. Crossed the materials used are ordinary room temperature paint (paint cold), heat paint, paint, and are developed to melt, hot melt (thermoplastic). The use of hot paint and melt plastic, they can join the pre-reflective glass beads, thereby increasing the visibility of rain and fog weather and at night. In addition, there is a glue line, a good system of special characters in advance or digital, use spray adhesive in paste Department after the paste can be. 1.1 By way of a crossed classification:Crossed by walking machine can be divided into：Walk behind, self-propelled, truck. Walk behind, the general was divided into two forms, one to rely on the human drive and control the direction of travel and crossed; the other a kind of engine as the driving force, but who controls only the direction of travel and crossed. Mainly applicable to urban areas, special graphics, crossed into the complex work. Self-propelled chassis and common chassis with two dedicated. Simple operation with institutions and power plant. Working drivers and operators generally operate separately. Its power and larger capacity, and speed and dash speed are faster, can be used for a wide range of marking work. The characteristics of vehicle crossed equipment are all set in a large truck chassis, so material storage tank capacity greater than the self-propelled, rapid transfer, applicable to the situation far from the base site. 1.2 By the use of the spray material categories: By the use of the spray material can be divided into cold paint marking machine and thermoplastic paint marking machine marking machine. Cold paint line machine with a low pressure air spray and airless spray two cold high-pressure spray equipment. Low pressure spray from the spray tank with gas, thinner cans, pipes, and cold spray gun component. Work, paint is 0.150.3 MPa low-pressure air compression along the conveyor to the spray gun, nozzle orifice, the swelling in the formation of the first spray. After the paint spray gun exit of the flow in the high-pressure atomizing air was 0.7MPa violently ejected form the second atomization. After the paint spray nozzle through the ground after the mechanical bonding between the effect produced, marking the formation of coatings. Its characteristics are: (1) Spray fine, but there is air rebound, emitting a splash of paint, resulting in the so-called flash phenomenon; (2)Can be sprayed coating low viscosity, the construction of more solvent to be added; (3)Flow is small, difficult to get a thicker coating (film thickness less than 0.3 ram), marking a sense of lack of effort; (4) Quality of the coating by the spray in the air from water, Oil of. Airless spray-type marking machine is the use of special high-pressure pump to the paint applied 10 15 MPa pressure, and then through the spray gun on the ground, high pressure pumps form a piston and diaphragm type 2. Such equipment spray marking out neat, attractive, due to pressure from large, free from paint viscosity, without diluting solvent, spraying out so thick and uniform marking, it is more widely used. Thermoplastic paint marking machine is hot-melt or hot melt plastic in the hot melt tank heated to temperature (usually 180 200 C). It crossed the way to have Scratch-type, extruded, spray-type 3. One type is similar to the cold spray paint marking machine; Scratch type is 10 cm wide by the hard Scratch plate to dash; and extruded through the full width of the extrusion device can be adjusted to a line of demarcation. Heat gun in the overall structure of the cold spray gun with different cycle around it were heat conducting oil surrounded by high-pressure air atomization is heated in advance, so to maintain the hot melt coating process in the whole work the higher temperature. Its characteristics are: (1) Designation of the standard line of clear, clean, and full, it has a thick and uniform coating, wear resistance, high pressure airless spray life of 2 to 3 times longer; (2)There is air bounce, so paint flying seriously, draw a marked line with flash; (3)Poor adhesion, the best non-air-spray equipment with high pressure spray first layer of the substrate, increased adhesion; (4)Marking the lack of a certain surface roughness, In case of ground water, easily lead to skidding; (5) Process and high cost, on the road demanding the best for the new road. 2, Line machine exists in the use of the key issues and development direction: Although a wide range of existing line machine, but there are still some outstanding issues that affect their promotion and use. Analysis of the causes, the following factors are key: (1) Paint is not enough pressure, affecting the quality of marking. China has crossed machine paint 6 MPa pressure is generally about, the film thickness of 0.2 mm. Actual use of that, after spraying road marking designated use of usually 2 to 4 months stitch started peeling off. This is mainly due to low pressure spray paint, lead paint thinner, can quickly penetrate into the formation, the poor adhesion with the ground. Staff should use the new high-pressure pumps, paint pressure increase (outside had reached 20 MPa), to ensure the quality of marking. (2) Improper use of jet components. Various types of spray nozzles are the best distance or range of spray angles. From the high point of the nozzle will increase the line width increases, the line is not clear, and the film thickness is reduced; distance is too low, injection angle decreases, the film thickness, drying time, extend, and easy to have a glitch Flow coating phenomenon. Therefore, the choice of the nozzle should be consistent with the performance of paints and arranged in position to meet the requirements of the nozzle the scope of work. (3) arking the defective design of control system. Existing line marking machine program and is very vulnerable to go the wrong fashion, irregular and so on; in the corner radius of smaller operations can not be crossed; in particular, repeated the old line of the function can not be achieved. Always need to manually program a line every once adjusted, work efficiency and labor intensity can be imagined. The generation of these control mechanisms functions as imperfect Centre at. Therefore, the use of computer-based image recognition technology automatically detects and servo position tracking technology that will significantly improve the efficiency crossed. The system consists of black and white CCD camera, frame grabber, a computer or microcontroller, servo position tracking system, control software and other components. In the liner operations, the general design standards of pre-fight by points, determine the location and marking the line marking machine running. According to hit the point, sub-pull, continuous operation. Therefore, the precise tracking of the pre-pull operation to ensure the quality of marking the key. Based vision sensor can pull tracking control system, taken directly from the CCD visual sensor or the original road and pull the old standard line of black and white image, by Marr edge operator to extract the image processing method is accurate location information. Paint spray gun movement servo control can be used to achieve self-tuning fuzzy controller, the control object without knowing the exact mathematical model of the case, by detecting the pull or the original old markings of the tracking error for fuzzy reasoning, the optimal control decision making. After these technical improvements,