Disassemblability of mechanical parts in automobile for recycling

Recycling of parts in automobile become important due to energy and environmental aspect. This study analyzes geometrical and material characteristics of parts, subassemblies and joining elements used in automobile. It also and analyzes disassembly mechanism between parts and sub-assemblies to improve disassembly process in a scrapped automobile. Disassembly is defined based upon disassembly mechanism and disassembly process. Finally, guidelines of design rules to improve disassembly is proposed and evaluated quantitatively using a case study of an automobile.     

A real-time sequence control system for the level production of the automobile assembly line

In the automobile industry, mixed-model assembly lines are used to produce many different vehicles without carrying large inventory. For achieving high productivity, it is required to keep a constant rate of usage of parts used by the assembly line. We have developed a new dynamic sequencing method for level production of assembly line and built up an automated sequence-control system which had been operated manually. In this paper, we present i) the nature of sequence control problems, ii) a dynamic sequence control algorithm, and iii) the experience of automating a buffer control system.     

A production base-stock policy for recycling supply chain management in the presence of uncertainty

This study focuses on solving master planning problems for a recycling supply chain with uncertain supply and demand. A recycling supply chain network includes collectors, disassemblers, remanufacturers, and redistributors working from the collection of returned goods to the distribution of recovered products to the market. The objective of this study is to maximize the total profit of the entire recycling supply chain. Considering the stochastic property of the recycling supply chain, this study institutes stocking and processing policies for each member of the recycling supply chain to better respond to unknown future demand. We propose a heuristic algorithm called stochastic recycling process planning algorithm (SRPPA) to address master planning problems in the recycling supply chain and its supply and demand uncertainties. The main SRPPA process consists of three phases. In the leader determination phase, SRPPA identifies the most important node as the leader of the recycling supply chain. In the candidate policy set generation phase, SRPPA defines the search range for the inventory policy and forms the candidate policy sets based on the characteristics of the leader. In the best policy set selection phase, SRPPA constructs the simulation process for each inventory policy candidate to identify the best policy set. A scenario analysis is then presented to show the effectiveness and efficiency of SRPPA.     

On the importance of sequencing decisions in production planning and scheduling

We discuss the traditional hierarchical approach to production planning and scheduling, emphasizing the fact that scheduling constraints are often either ignored or considered in a very crude way. In particular, we underline that the way scheduling is carried out is crucial for the capacity constraints on the lot sizes. Usual methods to handle capacity in theory or in practice are reviewed. Finally, we present an approach that tries to overcome these drawbacks by capturing the shop–floor capacity through scheduling considerations.     

A study on the subjective feeling affecting tactile satisfaction of leather in automobile: A structural equation modeling approach

Customer expectations for automotive design are increasingly rising, which plays an important role in purchasing behavior. Among them, automobile interior materials are one of the factors that have a significant influence on the overall luxuriousness and satisfaction of automobiles. One of the main affective responses to automotive interior materials is a tactile sensation, and since it is complexly constructed, systematic modeling is required. The current research proposed and tested a structural equation model (SEM) that describes hypothesized relationships among affective variables affecting tactile satisfaction such as luxury, soft, slippery, smooth, bumpy, and thick. A total of 26 samples including natural and synthetic leather using interior material in an automobile was selected as a stimulus to recruit 53 participants. All affective variables were found to affect luxuriousness that subsequently affected tactile satisfaction (path coefficient = 0.652). In particular, perceived softness was a dominant factor affecting tactile luxuriousness in leather (path coefficient = 0.305). The findings of the present study have significant implications for both theory and practice on affective responses and levels that affect tactile satisfaction in leather using automobile interior.     

Heuristic based evolution for the coordination of autonomous vehicles in the absence of speed lanes

The current state of the art in the planning and coordination of autonomous vehicles is based upon the presence of speed lanes. In a traffic scenario where there is a large diversity between vehicles the removal of speed lanes can generate a significantly higher traffic bandwidth. Vehicle navigation in such unorganized traffic is considered. An evolutionary based trajectory planning technique has the advantages of making driving efficient and safe, however it also has to surpass the hurdle of computational cost. In this paper, we propose a real time genetic algorithm with Bezier curves for trajectory planning. The main contribution is the integration of vehicle following and overtaking behaviour for general traffic as heuristics for the coordination between vehicles. The resultant coordination strategy is fast and near-optimal. As the vehicles move, uncertainties may arise which are constantly adapted to, and may even lead to either the cancellation of an overtaking procedure or the initiation of one. Higher level planning is performed by Dijkstra's algorithm which indicates the route to be followed by the vehicle in a road network. Re-planning is carried out when a road blockage or obstacle is detected. Experimental results confirm the success of the algorithm subject to optimal high and low-level planning, re-planning and overtaking.     

卷烟企业制丝车间基于仿真的生产计划与调度系统集成的研究

本文首先分析了卷烟厂制造执行系统的特点以及发展现状,描述了一个生产计划、仿真和调度集成系统。描述了集成系统的框架及主要组件的功能,以及集成系统的运行机制。该系统利用仿真技术将企业的生产计划与作业调度紧密集成,实现了计划部门与生产部门在信息和流程上的紧密关联。     

机器人运动规划中的姿态空间建模方法研究

提出机器人运动规划中的一种姿态空间建模方法,其基本思想是在工作空间中定义具有某种特征的点为基本碰撞体,可用于机械臂在复杂环境中的运动规划建模。实验表明该建模方法是有效可行的。     

Artificial Intelligence Applications in the Development of Autonomous Vehicles: A Survey

The advancement of artificial intelligence (AI) has truly stimulated the development and deployment of autonomous vehicles (AVs) in the transportation industry. Fueled by big data from various sensing devices and advanced computing resources, AI has become an essential component of AVs for perceiving the surrounding environment and making appropriate decision in motion. To achieve goal of full automation (i.e., self-driving), it is important to know how AI works in AV systems. Existing research have made great efforts in investigating different aspects of applying AI in AV development. However, few studies have offered the research community a thorough examination of current practices in implementing AI in AVs. Thus, this paper aims to shorten the gap by providing a comprehensive survey of key studies in this research avenue. Specifically, it intends to analyze their use of AIs in supporting the primary applications in AVs: 1) perception; 2) localization and mapping; and 3) decision making. It investigates the current practices to understand how AI can be used and what are the challenges and issues associated with their implementation. Based on the exploration of current practices and technology advances, this paper further provides insights into potential opportunities regarding the use of AI in conjunction with other emerging technologies: 1) high definition maps, big data, and high performance computing; 2) augmented reality (AR)/virtual reality (VR) enhanced simulation platform; and 3) 5G communication for connected AVs. This paper is expected to offer a quick reference for researchers interested in understanding the use of AI in AV research.      

Understanding the molecular basis of stability in Kunitz (STI) family of inhibitors in terms of a conserved core tryptophan residue: A theoretical investigation

β-trefoil is one of the superfolds among proteins. Important classes of proteins like Interleukins (ILs), FibroblastGrowth Factors (FGFs), Kunitz (STI) family of inhibitors etc. belong to this fold. Kunitz (STI) family of inhibitors of proteins possess a highly conserved and structurally important Trytophan 91 (W91) residue, which stitches the top layer of the barrel with the lid. In this article we have investigated the molecular insights of the involvement of this W91 residue in the stability and folding pathway of Kunitz (STI) family. Winged bean Chymotrypsin inhibitor (WCI), a member of Kunitz (STI) family was chosen as a model system for carrying out the work. Molecular dynamics (MD) simulations were run with a set of total six proteins, including wild type WCI (WT) & five mutants namely W91F, W91M, W91A, W91H and W91I. Among all of them the coordinates of four proteins were taken from their crystal structures deposited in the Protein Data Bank (PDB), where as the coordinates for the rest two was generated using in-silico modelling. Our results suggest that truly this W91 residue plays a determining role in stability and folding pathway of Kunitz (STI) family. The mutants are less stable and more susceptible to quicker unfolding at higher temperatures compared to the wild type WCI. These effects are most pronounced for the smallest mutants namely W91H and W91A, indicating more is the cavity created by mutation at W91 position more the proteins becomes unstable.     

A numerical tool to simulate the kinematics of the ingress movement in variably-dimensioned vehicles for elderly and/or persons with prosthesis

This paper presents a method for simulating the kinematics of the vehicle ingress movement of elderly people and/or people with prostheses (represented by a humanoid mannequin with a head, trunk, pelvis and lower limbs) in variably-dimensioned vehicles, starting from real experimental data. To solve this “complex” problem, we propose a three-stage method. The first stage concerns the construction of an “exploitable” movement database, containing movements resulting from the numerical processing of the ingress movements measured in experiments carried out on two vehicles with 2 distinct geometries. The second stage, consisting of 4 phases, analyzes and automatically identifies the ingress movement strategies. By the end of this stage, 2 ingress strategies and 6 sub strategies were identified. The third stage is the simulation. It uses the results from stages 1 and 2 to simulate the ingress movement of a subject in the database, adopting a given sub-strategy for a vehicle with a different geometry. The simulation of the ingress movement of the same subject but for another vehicle is formulated as an inverse kinematics problem, which is solved by constrained nonlinear programming.Simulations involving elderly people and/or people with prostheses made it possible to validate the proposed method for the two ingress strategies. Despite the differences with the measured movements, the simulated movements conform to the sub-strategies adopted by the subjects during the experiments. Furthermore, the simulations made it possible to partially explain the shifts in strategy of some subjects when they changed vehicles during the experiments. Finally, simulations on fictitious vehicles highlighted some of the limitations of our simulation tool. This study opens several perspectives for future research. For example, we could improve the simulation tool by considering the subjects' intra-individual differences.Relevance to industryThis study can aid ergonomists and car manufacturers to simulate the ingress movement in variably-dimensioned vehicles for elderly and/or prosthesis having persons. The results of the simulations can be used in the products' (Vehicles) evaluation and adaptation processes. The developed methodology can be extended to the simulation of other movements as it can be integrated into digital human models (DHMs) software.     

改进RRT算法在未知三维环境下AUV目标搜索中的应用

针对未知水下环境下的自主水下航行器（autonomous underwater vehicle,AUV）目标搜索问题,传统方法搜索速度慢且以解决二维平面下搜索问题为主,本文提出了一种基于改进RRT (rapid-exploration random tree)的未知三维环境目标搜索算法。在搜索方面,分别建立了包括目标存在概率地图、不确定度地图、区域遍历度地图在内的实时地图并设定其更新规则,根据搜索目标建立决策函数;在局部规划方面,将滚动规划与改进RRT算法相结合,规划出到搜索决策点的路径。二者的结合,实现了AUV在三维空间下在线实时搜索。仿真表明,该算法具有较强的遍历能力,提高了三维空间下目标搜索的速度。