基于RobotStudio的码垛机器人控制系统设计

【目的】通过对码垛机器人的控制系统进行优化设计,提高码垛机器人控制系统功能的合理性、高效性和便捷性,使码垛系统协调、合理地流畅运行。【方法】课题组选取智能制造系统中执行单元码垛机器人的控制系统为研究对象,依据智能制造体系中码垛机器人的作业任务,设计了码垛系统的布局和控制流程,采用RobotStudio软件中的Smart组件设计了系统的I/O信号控制逻辑、传送带控制逻辑以及吸盘工具的控制逻辑,并对码垛系统进行搭建与仿真,通过码垛系统仿真运行可得机器人末端执行器的运动轨迹和轨迹点坐标值,验证码垛机器人控制系统功能的合理性、高效性和便捷性。【结果】该控制系统能够较好实现左右码垛任务,具有稳定性、安全性和高效性。【结论】将优化后的码垛机器人控制系统应用于智能制造生产体系中,可实现高品质和高效率的智慧生产,系统应用前景广阔。     

基于PLC的采摘机械手电气自动化技术研究

为了提高采摘机器人电气自动化的效率、水平及机器人的智能化程度,在采摘机械手的设计上引入了PLC控制系统,并利用PID控制算法对自动化系统进行了改进,提高了自动定位和采摘动作控制的精度。为了验证方案的可行性,模拟采摘机器人的作业环境,采用MCGS软件设计了采摘机械手作业的监测系统,并对采摘的漏采率和破损率进行了测试。测试结果表明:基于PLC的采摘机械手具有较低的漏采率和破损率,可以满足较高精度的采摘机器人设计需求。     

基于PLC的新型工业码垛机器人控制系统设计

码垛技术作为现代物流自动化领域中的一门新技术,其随着我国科学技术的高速发展,也实现了技术的更新与升级。码垛机器人的运用为企业节约了大量的人力,降低了企业运营成本,提高了企业服务的效率,具有十分重要的社会意义。本文就主要分析了基于PLC的新型工业码垛机器人控制系统的设计,根据码垛机器人的工作流程和企业的实际需求,设计出人机交互的操作界面,以提高码垛机器人控制系统的稳定性和可靠性,更好的满足企业生产实际的需求。     

基于PLC的苹果采摘机械手运动控制系统设计

以苹果采摘机械手运动控制为研究对象,对机械手进行运动学分析与建模,设计了基于PLC的机械手硬件框架与运动控制方案、人机交互上位机和机械手轨迹规划的实验系统。实验结果表明:采用PLC控制器的苹果采摘机械手软硬件均能正常运行,该系统具有可靠性高、实时性和稳定性好等优点,对于农业采摘机器人快速识别目标并进行正确采摘作业具有很大帮助。     

双闭环控制采摘机器人机械手设计——基于PLC和CAN总线

采用双闭环控制系统,基于PLC运动控制器和CAN总线,提出了一种新的采摘机器人机械手关节分布式控制方案,并采用模块化思想设计了机器人关节电机控制系统、CAN模块及PLC控制器。采摘机器人机械手的关节采用谐波减速器进行调节,利用霍尔传感器和红外线传感器及光电编码器进行图像、转速和障碍物触碰的信号采集,采集信号利用A/D转换器将数据传输给PLC控制器。机械手的执行末端采用CAN总线控制,并利用变频器传递的通信信号,实现了末端执行器的并行控制,使多机械手处于最佳动作状态。最后,在双闭环控制方案的基础上加入了前馈控制环境,利用前馈控制环节可以实现对系统的实时控制,改善了系统的静态性能,实现了机械手对实际采摘位置的有效追踪。实验和仿真模拟表明:位移时间曲线平滑无突变,表明机器人在运行过程中平稳、无振动,机器人工作的可靠性较高,对路径的追踪精度较高。     

基于PLC的化工行业工业机器人平台设计

在化工行业进行工业机器人的应用可以减轻了劳动强度,减少危险性生产的人工操作环节,是当前社会与企业需要以及技术推动的共同作用的需求。本文设计了基于PLC控制的机器人机械手控制平台,用PLC为主控制器实现了机械手的自动化操作。实验证明能够达到设计需求,实现预期功能,能够适应于工业生产。     

工业机器人装调应用与维护实训平台研究与设计

工业机器人在智能制造领域占据着举足轻重的地位,MES总控单元充当大脑,通过PLC逻辑单元把机器人、数控车床及加工中心连接起来,通过编制好的程序安排加工成产。随着国家老龄化日益严重,劳动力大幅减少,用工荒、招工难成为企业首先需要解决的难题。笔者结合多年来从事智能产线工业机器人教学维修经验,着重介绍了在智能制造产线上机器人安装和调试的整体设计方案。实训平台由机器人机械装配与调试实训平台和机器人电气安装与调试实训平台两大部分构成,并配置轨迹描绘、搬运、码垛等典型应用实训组件。     

采摘机器人机械手虚拟现实和仿真技术研究

为了提高采摘机器人机械手群体作业的效率和精度,基于蚁群算法,将机器人虚拟仿真平台引入到了采摘机器人机械手的设计上,并利用C语言流程图编程,对采摘机械手、待采摘果实等进行了建模,在虚拟现实环境中对机械手的作业情况进行了仿真模拟。通过模拟结果对采用蚁群算法和不采用蚁群算法时机器人机械手的作业效率和采摘定位精度进行了对比,结果表明:采用蚁群算法可以明显提高机器人机械手的作业精度和作业效率。     

基于PLC的磁卡抓取气动机械手控制系统设计

为了提高脸盆智能制造生产线的智能化和自动化水平,降低工人的劳动强度,本文设计了一种基于PLC的磁卡抓取气动机械手,该气动机械手根据脸盆生产线的生产工艺,每隔10个盆放入一张磁卡,以便于AGV小车进行脸盆的入库管理,通过气动机械手装置的搭建、PLC的选型、PLC软硬系统的设计,最终满足了生产线的工作要求,有助于提高企业的生产效率。     

一种码垛机器人的电气控制系统设计

为进一步改善用于农产品成箱搬运、码垛的码垛机器人自动化作业效率，提升自动码垛的作业效果，融合先进成熟的电气控制技术，针对码垛机器人的电气控制系统展开设计研究。在当前码垛机器人作业原理的基础上，基于PID调控原理，结合各关节臂的结构特性与运动插补函数，建立了用于码垛机器人电气系统设计的理论模型，通过软件控制与硬件选型形成完整可行的电气控制系统，并进行码垛作业试验。试验结果表明：与具有普通电气控制系统的码垛机器人相比，该电气控制系统稳定性好，应用到码垛机器人后，其码垛准确率与各关节臂的避障成功率均可提升至90%以上，码垛综合效率得到明显提升。     

Regulation of irrigation canals

This article suggests and defines a characterisation of irrigation canal regulation methods, based on four criteria: considered variables (controlled, measured, and control action variables), logic of control, design method (structure and technique) and field implementation (configuration and device). Depending on the chosen criterion and partition rule, different classifications can be built from this characterisation. In conclusion, a structured characterisation table of the main published canal regulation methods is presented.Abbreviations ASCE American Society of Civil Engineers - CACG Compagnie d'Aménagement des Coteaux de Gascogne - CARA Compagnie d'Aménagement Rural d'Aquitaine - CARDD Canal Automation for Rapid Demand Deliveries - CEMAGREF Centre National du Machinisme Agricole, du Génie Rural, des Eaux et des Forêts - CNABRL Compagnie Nationale d'Aménagement du Bas — Rhône Languedoc - ELFLO Electronic Filter and Level Offset - FB Feedback or closed — loop control - FB _dn Feedback or closed-loop downstream control - FB _mi Feedback or closed-loop mixed control - FB _up Feedback or closed-loop upstream control - FF Feedforward or open-loop control - GPC Generalised Predictive Control - LQR Linear Quadratic Regulator - MIMO Multiple Inputs, Multiple Outputs - nI mO n Inputs, m Outputs - P Perturbation - P Estimation of perturbations - PID Proportional, Integral, Derivative Controller - PIR Contrôleur Proportionnel, Intégral, Retard (PI Delay controller) - Q Discharge in the canal - Q _dn Downstream discharge in the canal - Q _in Intermediate discharge in the canal - Q _up Upstream discharge in the canal - SCP Société du Canal de Provence - SISO Single Input, Single Output - U Control action variable - V Volume in a canal pool - V Elementary control action variable - w Regulator gate opening - Y Controlled variable - Y _c Target controlled variable - y Water elevation - y _dn Downstream water elevation of the pool (therefore upstream of a regulator) - y _in Intermediate water elevation in the pool - y _up Upstream water elevation of the pool (therefore downstream of a regulator) - Z Measured variable     

Comparison and sensitivity of measurement techniques for spatial distribution of soil salinity

In Khorezm, a district of Uzbekistan situated in the Aral Sea Basin, soil salinization is an important driver of soil degradation in irrigated agriculture. The main objective of this study was to identify techniques that enable rapid estimation of soil salinity. Therefore, bulk electrical conductivity of the soil (EC_a-meas) was measured with three different devices (2P, 4P, and CM-138) and electrical conductivity of the soil paste (EC_p-meas) was measured with the so-called 2XP device. These measurements were compared with independent estimates of EC_a-calc and EC_p-calc based on laboratory measurements of the saturated extract, EC_e, of soil samples from the same sites. Soil salinity could be assessed satisfactorily with all four devices. EC_p-meas could be well reproduced by the 2XP device (R ² = 0.76), whereas EC_a-meas estimates using 2P, 4P, and CM-138 in the field were less accurate (R ² < 0.50). The sensitivity of all devices to the main ions Cl⁻ and Ca^{2 +} suggests that the measuring principles are similar for all instruments. The devices can therefore be used interchangeably. Field assessment of soil salinity was considerably enhanced by the use of CM-138, because large areas can be quickly assessed, which may be desirable in spite of the lower accuracy.     

Evaluation of a crop water stress index for irrigation scheduling of bermudagrass

This study was conducted to assess crop water stress index (CWSI) of bermudagrass used widely on the recreational sites of the Mediterranean Region and to study the possibilities of utilization of infrared thermometry to schedule irrigation of bermudagrass. Four different irrigation treatments were examined: 100% (I₁), 75% (I₂), 50% (I₃), and 25% (I₄) of the evaporation measured in a Class A pan. In addition, a non-irrigated treatment was set up to determine CWSI values. The status of soil water content and pressure was monitored using a neutron probe and tensiometers. Meanwhile the canopy temperature of bermudagrass was measured with the infrared thermometry. The empirical method was used to compute the CWSI values. In this study, the visual quality of bermudagrass was monitored seasonally using a color scale. The best visual quality was obtained from I₁ and I₂ treatments. Average seasonal CWSI values were determined as 0.086, 0.102, 0.165, and 0.394 for I₁, I₂, I₃, and I₄ irrigation treatments, respectively, and 0.899 for non-irrigated plot. An empirical non-linear equation, Qave=1+⌊6[1+(4.853 CWSIave)^2.27]^−0.559⌋$Q_{\text{ave}}=1+⌊6{[1+{(4.853\text{CWS}{\text{I}}_{\text{ave}})}^{2.27}]}^{-0.559}⌋$, was deduced by fitting to measured data to find a relation between quality and average seasonal CWSI values. It was concluded that the CWSI could be used as a criterion for irrigation timing of bermudagrass. An acceptable color quality could be sustained seasonally if the CWSI value can be kept about 0.10.     

Improvement of FAO-56 method for olive orchards through sequential assimilation of thermal infrared-based estimates of ET

The aim of this study is to use the FAO-56-based single crop coefficient approach to estimate actual evapotranspiration (AET) of an olive (Olea europaea L.) orchard in the Mediterranean semi arid region of Tensift-basin (central Morocco) during two consecutive growing seasons (2003 and 2004). The results showed that using crop coefficients K_c suggested by FAO-56 method yielded an AET overestimation by about 18% when compared against eddy covariance measurements. Therefore, the determination of appropriate K_c values is required to accurately estimate crop water requirement of olive orchards in such water scarce area.In this study, after applying the K_c values derived over olive orchard in Spain by Pastor and Orgaz [Pastor, M., Orgaz, F., 1994. Riego deficitario del olivar: los programas de recorte de riego en olivar. Agricultura 746, 768-776 (in Spanish)], a better agreement was observed between measured and simulated AET. The root mean square error (RMSE) was reduced by about 28%, from 0.80 to 0.61 mm/day for 2003 and from 0.93 to 0.69 mm/day for 2004. The used K_c values of olives at three crop growth stages (initial, mid-season and maturity) were 0.65, 0.45, and 0.65, respectively, the mid-season stage value being considerably lower than that suggested by the FAO-56.Despite these improvements in the performance of AET simulations, some discrepancies between measured and simulated AET remained, especially when water stress occurred. These discrepancies were ascribed to the estimation of the stress coefficient K_c To overcome this problem, we assimilated into FAO-56 single source model estimates of AET derived from a simple energy balance model along with thermal infrared observations. The latter were collected with the ASTER sensor in 2003 and from ground-based measurements in 2004. The results showed a clear improvement for FAO-56 performances after assimilation: for 2003 and 2004, the RMSE values between observations and simulations, respectively, dropped down from 0.61 to 0.52 and from 0.69 to 0.46 (corresponding to relative reductions of 15 and 40%, respectively).     

移栽期对毕纳1号烟草气候斑病发生及生长的影响

为探明毕纳1号烟草最适移栽期,研究移栽期对烟草气候斑病的发生和生长的影响。结果表明:适宜的移栽期有利于减轻毕纳1号烟草气候斑病的发生,可改善毕纳1号烟草农艺性状、提高烟叶叶绿素含量,并在一定程度上间接提高烟株抗病性;其中4月27日移栽综合表现最佳,移栽后60 d发病率和病情指数分别为20.10%和2.67,较其他2个移栽期分别显著(P<0.05)降低9.66%～12.12%和1.30～1.61。该结果为毕纳1号烟草适时移栽和气候斑病综合防控提供了技术参考。     

Quantifying the sustainability of agriculture

The rural sustainability index is a scientifically based tool to quantify the performance of agriculture. The sustainability of crop production is quantified from three perspectives; people, planet and profit. Within each perspective, one condition was selected that must be met to warrant agriculture. These are: No hazardous work should be used within the crop production chain; agricultural crops should not be grown on land allocated to nature by national law or regulations and, when a GM-crop is present or is introduced in a region, it should not harm development opportunities of other farmers. If these excluding conditions are met, the sustainability of agriculture is assessed through five performance indicators on school attendance, water use and consumption, fertilizer use, pesticide use, and farm income. For each of the five indicators, critical values and target values have been given that limit the transition range between non-sustainable and sustainable production. The five indicators are combined into a sustainability index. The index aims at improving the socio-economic position of farmers while protecting the environment.

烟草破膜自动定位方法及比较

对烟苗种植过程中需要人工破膜提出了机械自动化破膜,为实现机械自动化破膜提出3种自动定位烟苗方法,利用双立目视觉机器采取信息图像进行定位破膜;采用3D激光扫描对烟苗进行信息采集定位以及利用精准农业这套整体测控系统全方面定位对这三种方法进行了阐述,并在实际烟草种植破膜过程中对3种方法的优缺点进行比较。     

Analysis of salinization dynamics by remote sensing in Hetao Irrigation District of North China

Remote sensing can provide base information for documenting salinity change and for predicting its future evolution trend. The spatial and temporal distributions of soil salinization of Jiefangzha Irrigation Sub-district, the western part of Hetao Irrigation District of Inner Mongolia in northern China, were determined through analysis of satellite-based remote sensing images. Three Landsat TM/ETM+ satellite images taken during 14 years (1991 ∼ 2005) coupled with field observations were chosen as the basic data sources. Supervised classification and visual interpretation were used to analyze salinity classification and statistical method was applied to analyze the relationship between salinity and groundwater depth. From 1991 to 2005 the area of heavy saline land decreased from 191 to 136 km², or 3.9 km² per year; the moderate saline land decreased from 318 to 284 km², or 2.5 km² per year; the slight saline land decreased from 510 to 394 km², or 8.2 km² per year. Therefore, soil salinization in Jiefangzha Irrigation Sub-district is decreasing in general. The electrical conductivity (EC) values measured from field have the following relationship with the reflectance composition obtained from LANDSAT Enhanced Thematic Mapper Plus (ETM+) data: EC = 5.653(band5 − band7)/(band5 + band7) + 0.246. In addition, an r² value between EC values and groundwater depth is 0.72, which indicates groundwater depth is the major factor for the regional soil salinity control. The paper can serve as a theoretical reference for optimal allocation of irrigation water resource and salinization control in Hetao Irrigation District.     

Possible utilization of high-salinity waters and application of low amounts of water for production of the halophyte Kochia scoparia as alternative fodder in saline agroecosystems

Production of halophytes using saline waters and soils and feeding them to livestock is one of the most sustainable methods of conservation in desert ecosystems, in addition to accomplishing food production for the people living in these areas. Therefore, to study the possibility of irrigating Kochia (Kochia scoparia L. Schrad) with minimum quantities of highly saline water for use as a fodder crop in arid environments stretching across saline waters, two experiments were carried out in the Research Farm of the Ferdowsi University of Mashhad, Iran. In the salinity experiments, two populations of Kochia, including the Sabzevar and Indian genotypes, were irrigated with ground water having electrical conductivity (EC) of 5, 15, and 20 dS m⁻¹. In the irrigation-treatment experiments, two local populations of Kochia, including Sabzevar and Borujerd, were subjected to four irrigation regimes as follows: complete irrigation (100%), 80%, 60%, and 40% of the water requirements using a saline ground water with EC = 5 dS m⁻¹. Because, the Indian genotype is preferred as an ornamental plant, it is not suitable for increased dry-matter production under high-salinity irrigation water compared to the local genotype (Sabzevar), which is suitable for forage. The Sabzevar genotype produced a large amount of dry matter (7530 kg ha⁻¹), even when irrigated with 20 dS m⁻¹ saline water. The best time for harvesting Kochia for fresh feeding is at the end of flowering (88 days after sowing or DAS), when the biomass is relatively high (6500 kg ha⁻¹) and the leaf-to-shoot ratio, as a quality index, is approximately 50%. The highest green-area index was observed at 15 dS m⁻¹ and decreased at high levels of salinity. Photosynthesis and transpiration rate did not decline significantly with increasing external salinity four weeks after salinization, but increased in both genotypes at 15 dS m⁻¹, indicating that the salinity-tolerance threshold of Kochia for both photosynthesis and transpiration reduction is above this salinity level. The Indian genotype also showed a very low seed yield (210 kg ha⁻¹) at low levels of salinity, whereas Sabzevar produced 1120 kg ha⁻¹ seed under the same conditions. Different irrigation regimes had a significant effect on the biomass and seed production of Kochia. The highest forage yield was obtained from complete irrigation, with 11.1 Mg ha⁻¹ dry material. Sabzevar local population represented a better performance in terms of all characteristics, except accumulation of inflorescence dry matter, and no significant effects were recorded. In conclusion, Kochia's high foliage production capacity in the presence of salinity and limited irrigation make this plant suitable for use as an alternative forage crop in harsh environmental conditions. There is a wide range of intraspecific variation in K. scoparia, but more investigation is needed to introduce it as a cash crop.     

Sensitivity analysis and field testing of the RISK-N model in the Central Valley of Chile

We present the results from a sensitivity analysis and a preliminary short-term, site-scale performance assessment of the analytical soil and groundwater nitrate transport RISK-N. The study was carried out in the Central Valley of Chile, on a 2.6 ha corn (Zea mays L.) field underlain by a shallow unconfined aquifer during the cropping season 2000–2001. Nitrogen levels in soils as well as NO₃⁻–N irrigation water and groundwater concentrations were monitored through the crop-growing period, the latter by a network of 16 monitoring wells. A sensitivity analysis shows that both the nitrate flux from the vadose zone and NO₃⁻–N groundwater concentration are mainly influenced by the initial soil nitrogen levels, water input, and soil porosity. Also, simulated groundwater NO₃⁻–N levels are sensitive to changes on the saturated zone denitrification constant. An additional analysis further reveals the significance of the latter parameter, in conjunction with the amount of applied nitrogen fertilizer. We obtained a good agreement between observed average and simulated values. While the model performs well when spatially averaged values are used (root mean square error, RMSE = 1.4 mg l⁻¹ of NO₃⁻–N), the prediction error increases (RMSE = 1.9 mg l⁻¹ of NO₃⁻–N) when the concentration in each well is considered. This fact could be explained by the time and space scale of the experiment and the characteristics of the RISK-N model. The model is easy to use and seems appropriate for mid- and long-term studies of nitrogen contamination in groundwater for agricultural conditions in the Central Valley of Chile and under limited field data availability conditions. However, it needs to be tested for longer periods and under different climatic conditions, soil types, and aquifer characteristics, before its range of applicability can be fully established and recognized.