高耐蚀性镀硬铬工艺研究

针对空客生产的A320机型合金钢零件镀硬铬层高耐腐蚀性的要求,研究了一种高耐蚀性镀硬铬工艺,所获得的镀铬层硬度为750～980HV,并且通过了750h的盐雾试验,满足空客技术要求。研究还发现,特殊的电镀硬铬工艺,尤其是镀铬后的HA油除氢、磨削等是提高硬铬镀层耐腐蚀性能的关键。该工艺目前已在工厂的批量生产中获得应用。     

A priori performance assessment of line-less mobile assembly systems

Present assembly systems are often based on rigid, line-based approaches and are hindered in their reconfiguration capability. Line-less Mobile Assembly Systems (LMAS) are a novel approach for assembly organization. They improve flexibility through mobile resources, permitting spatiotemporal freedom in scheduling and resource assignment. This paper presents a method for a priori assessment of LMAS during the early stages of the assembly system design process. The method applies a modified, extended mean value analysis to a closed queuing network representation of LMAS to estimate performance. The method is validated model analysis and comparison on two use cases indicating plausible model behavior.     

Manufacturing complexity in assembly systems with hybrid configurations and its impact on throughput

A measure of product variety induced manufacturing complexity has been proposed based on the choices of assembly activities that operators make in serial, manual mixed-model assembly lines. In this paper we extend the complexity measure to assembly systems with parallel and hybrid configurations. The complexity measure takes into consideration operator choices at each station and the assembly system configuration. In addition, we develop throughout analysis models for assembly systems by incorporating complexity based on the operator reaction time and fatigue effects. The complexity and throughput models are applied to comparing performance of assembly systems with different configurations.     

柔性装配系统规划设计研究

在系统研究柔性装配系统规划设计内容的基础上,从产品的整个生命周期出发,建立了柔性装配系统并行设计 整体约束网络模型,最后根据系统设计因素多且相互制约的特点,提出结合领域知识和遗传算法的人机一体优化策略对柔性装配系统进行规划设计。     

基于蚁群算法的混合品种装配线平衡问题研究

混合品种装配线平衡问题是一种典型的NP-Hard组合优化问题,文章采用蚁群算法,在给定工作节拍的条件下,以最小化工作站数为优化目标,采用启发式方法构造分配方案的生成策略,并且采用局部更新的信息素更新规则,达到提高装配线平衡率的目的.通过组合优先顺序图,将混合品种装配线平衡问题转变成单一品种装配线平衡问题进行求解.最后,通过实例验证了该算法的有效性.装配线平衡后,保持了生产线的柔性,同时提高了设备和人员的利用率.     

Methodological Approach and Reconfiguration Tool for Assembly Systems

Assembly lines design is intended to solve many problems related to assembly operations. The introduction of a new product should often entail the salvage of existing assembly lines. This work proposes a methodology for assembly line reconfiguration, to rationalize and support the redesign process of assembly systems. This research formalizes a representation model and a method for assembly line reconfiguration. The model describes the main characteristics and significant features of the assembly process. The study is concerned with three fundamental models, the first describes assembly line structures. The second illustrates component assembly features and the third produces all the assembly sequences. The assembly line reconfiguration method provides an analysis and estimation tool on the reconfiguration process complexity. The method proposed is also meant to be a tool to identify the operational flexibility limit. The method results point out the way to implement assembly system reconfiguration and gives detailed information about the assembly line. Each assembly line, facing a new product to be assembled, is processed with the reconfiguration method and receives operative results for reconfiguration process and quality indicators.     

工作流在混合流水车间调度问题上的应用

由于混合流水车间的调度问题是NP难题,难以得到它的精确调度结果;而且车间调度往往是动态过程,这又使得生产模式为混合流水车间的生产线的自动执行、资源指派和现场生产调度变得更加困难。文章提出了适合车间调度的工作流模型,建立了混合流水车间的流程定义;采用NEH启发式算法构造全局资源指派规则,同时构造了针对机器、工件的局部指派规则;将工作流技术应用于混合流水车间,在一定程度上解决了车间生产的自动化、优化及动态调度问题。     

面向敏捷生产调度与控制的基于MAS的制造系统

面对动态制造环境中制造系统必须面对的时间不确定性、设备可靠性/可用性、订单变化、人力资源变化等问题,提出一种面向敏捷生产调度与控制的基于MAS的制造系统组织框架以支持进行有效的生产调度和控制.引入招投标方法实现任务的分解与分配,通过制造任务的分解与分配建立各层Agent之间的协调工作及协同决策机制;采用能力匹配与动态调度相结合的方法实现任务分配与调度控制的有效集成;面向生产任务需求动态确定Agent粒度、组建MAS模型;为了便于构造各种Agent,提出一种Agent的多层混合结构.从而制造系统中的各种制造资源被重组成为Agent网络,使其能够利用各种Agent的自治和合作特性适应制造环境的变化,实现动态调度与控制.     

Simulation-based planning and evaluation of personnel scheduling in knowledge-intensive production systems

Personnel scheduling provides manufacturing companies the link between personnel and production planning. Scheduling has a significant influence on the development of employee competencies. In knowledge-intensive production systems, this results in substantial impact on the flexibility and productivity of the production. Nevertheless, in industrial practice the employee competence and production planning are considered largely separate. The considered assembly line of a manufacturer of domestic appliances consists of extensive manual operations. In such a production system the employees have a strong and dynamic impact on productivity and flexibility of the production system due to learning effects. For this reason, it is necessary to know the impact of the employee competence on the production targets to enable a high accuracy of production planning. Therefore, a concept will be shown to describe learning and forgetting processes of production employees. These processes and productivity impacts are validated in collaboration with the manufacturer of domestic appliances. An experimental simulation model of the assembly line is created and the relevant learning and forgetting events are integrated for planning and evaluation of employee competencies. Using the simulation model it will be shown how targeted development of competencies influences production flexibility and costs.     

Self-optimizing assembly of laser systems

Laser assembly can be a tedious task if performed manually. Especially if miniaturization of the laser is desired, robot-based assembly can greatly improve quality, performance and throughput, while self-optimization is regarded as a strategy to reduce planning efforts and increase the robustness of the assembly. An automated laser assembly system has been developed together with a concept to increase the autonomy through a multi-agent system control structure. The multi-agent system allows assembly steps like sequence planning, measurement of components and deviations, selection of components, soldering elements onto a carrier plate and active resonator alignment to be handled by the system itself and enables the assembly system to uniquely plan every laser system and execute its assembly within a flexible robot-based assembly cell.     

Constraints analysis and evaluation of manual assembly

The use of integrated ergonomic constraints for the objective evaluation of manual assembly sequencing is proposed in this paper. Feasible assembly sequences are generated and evaluated by a new Liverpool assembly sequence planning (LASP) system in terms of product geometry, assembly workstation layout, operator characteristics and posture. Two new evaluation criteria, i.e., visibility, accessibility or both, are applied in the optimization of the assembly sequencing. With LASP, possible design faults and optimum assembly sequence with maximum visibility and/or accessibility score is obtainable during the design stage. An illustrative case study of an air conditioner assembly is also presented.     

Self-adjusting multi-objective scheduling based on Monte Carlo Tree Search for matrix production assembly systems

As a response to the low utilization of production lines in the context of an increasing number of product variants with significant differences in cycle times, line-less modular assembly concepts known as matrix production have evolved. Whilst the many degrees of freedom a matrix production offers provide different ways to react to disturbances and balance utilization, it also increases the complexity for scheduling exponentially. For real-time scheduling high solution quality and high efficiency are needed. This paper contributes a multi-objective scheduling approach based on Monte-Carlo Tree Search that self-adjusts to the scheduling problem to improve solution quality and execution time.     

三维钢网自动组装生产线的设计

介绍一种轻型建材三维钢网组装生产线的组成及工作原理,分析了主要功能单元的结构和组装线设计的特点,并简述了控制系统的设计思想.该生产线的设计开发,为建材行业提供了一种新型自动化生产设备.     

智能制造车间设备动态能力分析技术研究

计划排产智能、生产过程协同智能、生产资源管控智能和决策支持智能等是智能制造车间的特点。为适应智能化制造,提出了一种面向智能制造车间的设备动态能力分析方法。在建立瓶颈设备负荷率模型的基础上,给出了设备动态能力评估算法。在多品种小批量的生产模式下,基于动态生产任务数据,结合改进型遗传算法,优化了设备利用率,降低了部分关键设备超负荷运行的可能,通过与实际情况比对,最终验证了该分析方法的有效性。     

Dual arm robot for flexible and cooperative assembly

Dual-arm robots provide efficient approach for automated execution of complex assembly operations. With bimanual-manipulation, a dual-arm robot can simultaneously control relative motion and interaction of assembly counterparts in a dexterous human-like manner. This requires, however, sophisticated programming and control algorithms for arms cooperation. This paper addresses the development of an advanced industrial dual-arm robot system with novel capabilities, such as easy and rapid commissioning, compliance control of bimanual interaction in all assembly process phases, as well as intuitive planning and programming. The robot can be leased and easily integrated in assembly environment sharing the same workspace with human workers.     

小吉星PRM应用模具生产的APS功能解读

小吉星PRM（流程资源管理）软件包含了APS（先进规划排程）的基础理论和主要功能,可把模具生产计划编制形式,从＂静态计划模式＂向＂动态优化排程＂转换,解决模具生产日程计划与加工作业排程计划的无缝衔接;提供产能与已接模具业务负荷的平衡以及物料适时到位的计划保障;提供模具交货期计算与加工能力平衡的可视化决策支持;动态自动生成模具交货期紧迫系数,作为确保交货期的优先等级排序依据;用排产推演法验证插单模具是否可行。     

Designing assembly lines with humans and collaborative robots: A genetic approach

Human-robot collaboration represents a significant evolutionary step in manufacturing. A crucial point is to establish a proper task assignment to combine robot productivity with human flexibility. In this regard, this paper proposes a genetic algorithm to approach the Assembly Line Balancing Problem (ALBP) in the case of human-robot collaborative work. The aim is the minimization of: i) the assembly line cost, evaluated according to the number of workers and equipment on the line, including collaborative robots, ii) the number of skilled workers on the line, iii) the energy load variance among workers, based on their energy expenditures and thus on their physical capabilities and on the level of collaboration with robots.     

基于MAS的MID-BOT两级生产计划与控制集成研究

针对生产计划与控制系统的不确定性、动态性和复杂性,提出一种基于MAS(Multi-Agent System)的物料需求计划向下与车间作业计划两个层次间(即M ID-BOT)两级生产计划与控制集成模型,讨论基于MAS的分级递阶和并行处理相结合的自治组织体系结构和运作模式,通过Agent能力匹配和改进的合同网协议来实现计划分解和任务分配,并设计模型中个体Agent的行为模型,从而利用两级集成的优化算法和Agent协商机制解决生产计划与控制的集成优化问题。     

A deformation model for tube extrusion

Plastic forming processes, the origins of which go back to ancient times, have become more popular in the last five decades, amongst other material-shaping processes. As the needs of the modern world and competition between the processes increase, knowledge of the deformation pattern of the material during a process is being recognized as primary information in the related field. Today, this kind of information is made use of in all areas associated with the process, from the planning of the plant to the ensuring of the quality of the final product.

In this study a deformation model for axisymmetric tube extrusion is proposed, in which the flow lines in the deformation zone are chosen as straight lines passing through a fixed point on the axis of symmetry and the exit surface of the deformation zone which is the plane at the die exit perpendicular to the axis of symmetry. A kinematically admissible velocity field is obtained from this deformation model and the parameter contained in the model is found by introducing this velocity field into the Upper-Bound Theorem. Since there is not a model for tube extrusion in the literature it was not possible to carry out a comparative study, which is why only the results obtained in the study are given, along with the indication of some further research directions.     

基于子装配的装配序列规划方法研究

为了提高复杂机械产品装配序列规划的效率,提出了基于子装配的装配序列规划方法.建立了基于有向约束图的装配模型,并给出了基于子装配的装配序列规划系统框架,从而将产品装配序列规划问题转化为子装配的装配序列规划问题;给出了子装配的相关定义,并从稳定性和干涉性两个方面设计了子装配的识别方法;最后,给出了系统算法流程图,并通过电机车轴承箱装配实例验证了该算法的有效性.