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。     

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.     

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     

Evaluation of the utilization of heated sewage sludge for peri-urban horticulture production in the Sahel of West Africa

Shortage of organic matter hinders agricultural production in the Sahel, and this lack of enough organic matter is more severe for peri-urban horticulture, which depends heavily on it. Alternative sources of organic matter that offer new options for peri-urban horticulture can help reduce the potential for conflict over finite resources between traditional crop production and peri-urban horticulture. Both agronomic and economic evaluations of an organic amendment called heated sewage sludge (HSS) were conducted in the research station of International Crops Research Institute for the Semi-Arid Tropics (ICRISAT)-Niamey, Niger, West Africa. For this study, HSS, a material imported from Japan, applied at a dosage application equivalent to 20.0 kg 100 m⁻² on lettuce fields led to production levels as high as those of conventional methods, and the yield became even higher than those of conventional methods when the dosage was increased to 50.0 kg 100 m⁻² and 100.0 kg 100 m⁻². Even though HSS was imported, its benefits outweighed its cost, as evidenced by the positive net returns. Since profitability in peri-urban horticulture is much higher than that of traditional crop production, the results of this study imply that if adopted, the use of HSS can lead to increased availability of organic matter for traditional cropping systems.     

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).     

Effect of irrigation uniformity on the profitability of crops

There are numerous models capable of simulating crop behavior under different water stress conditions. However, none of them takes into account the effect of irrigation water uniformity on yield. The model developed simulates the uniformity effect on yield and the repercussion on gross margin (GM). The application of the model to a maize crop in Albacete (Spain) indicates that for the same irrigation depth, an increase in uniformity of water in the soil (CU) corresponds to a 4% increase in yield for the common irrigation strategy in the area, and a 6.8% increase in yield for the optimal irrigation schedule established by the model. Values of percentage of adequately irrigated area (a) between 50 and 80% appear to be adequate for values of CU > 80%. This effect has special relevance on the GM mainly when designing the irrigation strategy of areas with limited water resources. This leads to improvement of CU from 75 to 95% for the common irrigation depth applied to maize and may increase GM up to 27%. For small irrigation depths, the effect of CU on GM is reduced. The maximum GM is reached at ET_a/ET_m < 1 and a <100%. The paper also describes a methodology for determining the most suitable irrigation schedule under regulated deficit irrigation conditions.     

Crop coefficient and evaptranspiration of onion at Awash Melkassa, Central Rift Valley of Ethiopia

Improved water management through precise crop water requirement determination is needed to improve the efficiency of water use in agricultural production. As a result, appropriate irrigation scheduling which can lead to water saving, improvements in the yield and income can be designed. In this study, three non-weighing lysimeters having dimensions of 2 m × 1 m × 2 m were used to determine water requirement (ET_c) and crop coefficient (Kc) of onion (Bombay Red cultivar). Reference crop evapotranspiration (ET_o) was determined using weather data recorded at the site. The measured ET_c values were 51.3 mm, 140.5 mm, 144.8 mm, and 53.9 mm during the initial, development, mid-season and late season growth stages respectively. Crop coefficient (K_c) values, calculated as ratio of ET_c to ET_o, were 0.47, 0.99, and 0.46 during the initial and mid-season stages and end of late season. Furthermore, third-order polynomials were fitted well to predict the crop coefficient values as functions of growing degree-days (GDD).     

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.

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.     

等氮量替代原则下沼液部分替代化肥技术方案

在土壤基肥施用翻耕前,采用沼液漫灌对于矫治土壤连作障碍、提高土壤肥力具有显著作用。结合这种沼液的施用方式,拟定沼液替代化肥的技术方案可为沼液的资源化利用及化肥使用的减量化提供一种可行的技术措施,从而有效缓解沼液的消纳困境,间接促进畜禽粪便的资源化利用。文章提出了等氮量部分替代原则下沼液替代化肥的技术方案,并举例说明了沼液用量、化肥减量等参数的计算方法,拟定出沼液替代后化肥的施用方案,依次试验分析了技术方案实施的应用效果,结果表明:技术方案实施后,每亩蔬菜可减少尿素、重钙及硫酸钾用量依次为9.65 kg,22.72 kg和10.92 kg;蔬菜品质有明显提升,蔬菜增产7.92%,每亩蔬菜可增加收入5830.6元。