积水化学成立于1947年，当初以制造和销售塑料相关产品的业务为主。1950年积水化学在日本首次开发出透明胶带；两年后，开始正式生产硬质氯乙烯管，为排水、供电、供气等基础设施建设做出了巨大贡献。1955年，积水化学在聚氯乙烯管接口的挤压成形技术上获得成功；进入70年代，又在日本首次开发出组合式住宅。
通过一个短片，整体感受一下该公司产品，3小时完成的一户建：
视频：Japan build house in 3 hours!
通过视频，可以看到，该系统采用模块化预制方案，预制率如此之高的模块化建筑，又要满足多变的客户需求，积水是怎么做到的？通过一篇该公司员工的论文，让我们一窥究竟。
《STRUCTURING OF SEKISUI HEIM AUTOMATED PARTS PICKUP SYSTEM (HAPPS) TO PROCESS INDIVISUAL FLOOR PLANS》
《构建SEKISUI HEIM自动化零部件提取系统(HAPPS)来处理独立的楼层平面图》
作者简介：
Jun FURUSE Housing Company, Sekisui Chemical Co., Ltd., 2-3-17 Toranomon, Minato-ku, Tokyo, Japan
Masayuki KATANO Housing Company, Sekisui Chemical Co., Ltd., 2-3-17 Toranomon, Minato-ku, Tokyo, Japan
1. Summary
综述
Sekisui Heim residential houses (herein “Heim”) are made of factory-produced modules called “Units” which can be combined to complete any house plan. All “Units” to compose a house are unique and have different parts in different combinations. It is an important process to select and pick up about 30,000 parts correctly for each house, out of about 300,000 listed parts and feed them to the production line in time of work. In this paper, the writer will introduce to you how to pick up the parts constituting Heim units, and certain technical points of the “HAPPS” (Heim Automated Part Pick-up System) which has materialized such method. In the end, the writer will touch on the efficiency and accuracy of such part pick-up method.
Sekisui Heim住宅(以下简称Heim)是由工厂生产的称为单元的模块组成，可以组合来完成任何住宅计划。所有组成房子的单元都是独一无二的，并且有不同的组合。从30万件已列明的零件中，正确挑选出3万件左右的零件并及时送到生产线上是一个重要的工序。在本文中，作者将向您介绍如何拾取构成Heim单元的部件，以及实现该方法的HAPPS (Heim自动拾取部件系统)的某些技术要点。最后，对这种零件拾取方法的效率和准确性进行了探讨。
Keywords: prefabricated house, bill of materials, parts explosion, just-in-time
关键词:装配式房屋，材料清单，零件爆炸，准时化
2. About “Heim”
2.关于海姆
2.1 Unit House Sekisui builds and sells 13,000 “Heim” houses annually, which are commonly called Unit House. The Units have steel frame structure and are fabricated mostly in factory to a level of about 80% completion. This process is called “Unit Method” and minimizes work load at construction site enabling fast and high quality house making. An advantage of “Unit Method” is freedom in floor plan selection which is allowed by the strong steel frame structure. Floor plan of contracted “Heim” is divided into several standardized segments for the production of best suited “Units”. (Fig. 1) There are about 70 kinds of Unit, of which 40 are standard cuboids varying in 10 lengths, 2 widths and 2 heights and others are special shape Units (trapezoid etc.).
Sekisui每年建造并销售13000套Heim住宅，通常被称为单元住宅。这些单元采用钢框架结构，大部分是在工厂制造的，完工率约为80%。这个过程被称为单元法，最大限度地减少了施工现场的工作量，从而实现了快速和高质量的房屋建造。单元法的一个优点是在平面选择上的自由度，这是强钢框架结构所允许的。海姆项目的建筑平面图被分为几个标准化的部分，以生产最合适的单元。(图1)单位约70种，其中标准长方体40种，长宽高各10种，其他为特殊形状单位(梯形等)。
2.2 Work flow from receipt of order to delivery Once the customer places an order, each house is processed separately. Firstly the sales company draws the floor plan and secondly at the factory all necessary parts are picked according to the floor plan. The Unit frames are made from steel stocks by welding and fed to the assembly conveyor line where the installation of exterior and interior parts and equipment to the frames is performed by workers. (Fig. 2) Lastly the Units are transported to the construction site and tied together to compose a house. (Fig. 3)
2.2从收到订单到发货的工作流程客户下单后，各房单独处理。首先由销售公司绘制平面图，然后在工厂根据平面图挑选所有需要的零件。单元框架由钢材通过焊接制成，并输送到装配线，工人在装配线上安装外部和内部部件及设备。(图2)最后，单元被运送到建筑工地，并捆绑在一起组成一个房子。(图3)
A large factory makes 135 Units a day (1 Unit every 3 minutes), each of which is consisted of different parts placed in different locations. It is important to select about 30,000 specific parts correctly out of about 300,000 listed parts and deliver them to the assembly line in time of work. Engine, seat, paint color, audio component, etc. may be chosen in the assembly of automobile but even layout of seats or windows or size and shape of body can be selected, so to say, in the assembly of Heim. Here we introduce a parts explosion system for such freedom of design.
一个大的工厂一天生产135个单位(每3分钟生产一个单位)，每一个单位由放置在不同地点的不同零件组成。从列出的大约30万个部件中正确地选择大约3万个特定部件，并在工作时间内将它们交付到装配线上，这是很重要的。汽车的装配可以选择发动机、座椅、油漆颜色、音响元件等，甚至可以选择座椅或车窗的布局或车身的大小和形状，也就是说，在Heim的装配中。在这里，我们介绍了一个零件爆炸系统，这种自由的设计。
3. Technical key points in parts explosion
3. 技术要点
There are two technical key points in the system. One is how to incorporate BOM (bill of materials) for ultra-high mix low volume production to give design freedom to customers who demand individual houses of all different floor plans, equipment and interior decoration. The other point is the explosion method which breaks floor plans down to parts.
该系统有两个技术要点。一个是如何结合BOM(材料清单)为超高混合低批量生产，给客户的设计自由，他们需要不同的平面图，设备和室内装饰的各个房子。另一点是爆炸法，它把平面图分解成各个部分。
3.1 BOM structuring In general assembling industry, a BOM is constructed by exploding the product down to intermediates and then to parts. (Fig. 4) Concept of BOM is based on the standard model, to which optional parts are tied. In Heim, no standard house can be offered because individual floor plans would vary so much. To deal with this situation, a concept of imaginary intermediate is created which is a group of parts closely related. (Fig. 5) BOM tied to a group of parts plays an important role to process individual floor plan. These imaginary intermediates may exist temporarily in the production process or can just be imaginary (dummy). It can be defined as “intermediates, whether real or imaginary, used for effective explosion of product to parts.” Identifying codes of these groups of parts are called MIM codes (Menu Item Master). MIM code consists of many digits which indicate, for example in case of exterior wall, dimensions, neighboring parts, interfacing condition, color, etc. (Fig. 6) Such BOM method, specialized for parts explosion, enables to expose any floor plan efficiently.
在一般的装配行业中，BOM是通过将产品分解成中间产品，然后分解成零件来构建的。(图4)BOM的概念是建立在标准模型的基础上，将可选的零件绑定在标准模型上。在海姆，没有标准的房子可以提供，因为个人的平面图会有很大的变化。为了解决这一问题，我们创造了一个假想的中间物的概念，它是一组密切相关的部分。(图5)与一组零件绑定的BOM对于处理单个的平面图起着重要的作用。这些虚构的中间产物可能在生产过程中暂时存在，也可能只是虚构的(虚拟的)。它可以被定义为中间体，无论是真实的还是想象的，用于产品到零件的有效爆炸。标识这些部件组的代码称为MIM代码(菜单项主代码)。MIM代码由许多数字组成，这些数字指示，例如在外墙、尺寸、相邻部件、接口条件、颜色等情况下(图6)。
(Example in external wall)
3.2 Parts explosion BOM and MIM are prepared at the stage of R & D and there are about half a million MIM codes per one series of Heim product. Orders from customers are actually processed individually by picking and combining about 4000 MIM codes in average per house, out of half a million codes. (Fig. 7) Picked MIM’s are matched to BOM’s which are designed for explosion to parts. This is the parts explosion method in Heim production.
3.2在研发阶段准备零件爆炸BOM和MIM;每个系列的Heim产品大约有50万个MIM代码。来自客户的订单实际上是通过从每户平均50万个代码中挑选并组合约4000个MIM代码来单独处理的。(图7)挑出的MIM s与设计用于零件爆炸的BOM s相匹配。这是Heim生产中的零件爆炸法。
4. Important technical points in the parts explosion system
4. 零件爆炸系统的重要技术要点
This efficient and accurate system of MIM pickup is called HAPPS (Heim Automated Parts Pickup System). The outline and the important technical points are explained below.
这种高效、准确的MIM拾取系统被称为HAPPS (Heim自动化零部件拾取系统)。大纲和重要的技术要点说明如下。
4.1 Outline of HAPPS HAPPS is a system to pick up necessary parts when a floor plan of production order is put in. HAPPS is consisted of information receiving section and processing section. (See Fig. 8) In the information section, input of floor plan data in graphic form, such as house type (snow accumulation class, exterior wall color, etc), Units, accessories (balcony, entrance porch), equipment (bath, kitchen), are converted to “objects”. “Object” is abstracted floor plan information expressed in dots, points, lines and rectangles. “Objects” compose a modeled house in the virtual space. (Fig. 9) In the processing section, “objects” are restructured (divided or combined) to new “objects” which suit MIM’s of pickup system. “Objects” are principally in 1-to-1 correspondence to MIM’s (groups of parts). “Objects” will meet and catch corresponding MIM’s and determine number or letter in each digit, in consideration of surrounding conditions. Fig. 9 shows a house expressed by Units and exterior walls and its conversion to a modeled house composed of “objects” in the virtual space
4.1 HAPPS大纲HAPPS是生产订单平面图放入时，拣取必要零件的系统。HAPPS由信息接收部分和信息处理部分组成。(见图8)在信息部分，将房屋类型(积雪等级、外墙颜色等)、单元、配件(阳台、入口玄关)、设备(洗浴、厨房)等平面数据以图形形式输入转换为对象。对象是抽象的平面信息，用点、线、矩形表示。在虚拟空间中，对象组成一个建模的房子。(图9)在处理部分，对象被重构(分割或合并)为适合拾取系统MIM s的新对象。对象主要以1对1的方式对应到MIM s(部件组)。对象将满足并捕获相应的MIM s，并根据周围的条件确定每个数字中的数字或字母。图9展示了用单元和外墙表示的房子，以及它转换成由虚拟空间中的物体组成的模型房子
4.2 Important technical points in HAPPS In HAPPS, it is an important process to convert intermediates to “objects” in the virtual space and to let the “objects” conform each other, prior to the pickup of right MIM.
在HAPPS中，将中间体转化为虚拟空间中的“对象”，并让“对象”彼此融合，是一个重要的过程，之后才是正确的MIM。
4.2.1 Conversion of intermediates to “objects”
4.2.1中间体向“对象”的转化
Based on the Unit information, location information within the Unit and interference information with other parts, “objects” are allocated to compose an abstract house, in places of actual intermediates, which process is required for parts pickup. Corresponding to the allocated “object”, MIM will be output referring to the surrounding conditions and selecting figure or letter of each digit. Conversion of intermediates to “objects” puts out MIM’s very efficiently, which otherwise require complicated judging. Configuration of exterior wall top (8th digit of MIM) is shown, as an example, in Fig. 10. There is an exterior wall on top of the exterior wall A. Hence, the “next part on top” is an exterior wall. There is no exterior wall nor Unit but roof on top of the exterior wall B. Hence the next part is roof. This information and other surrounding circumstances including interfering information of next part are required to identify the specific MIM. Similarly other digits such as ‘next part under bottom’ or ‘openings’ are determined in relation to the Units and other parts, As such, in the modeled house composed of “objects” in the virtual space, mutual positions of “objects” become clear and MIM’s can be identified accurately and efficiently. In addition, “objects” make the programming easier, by giving clear images of part fit. Also the visualization by “objects” makes the parts explosion very efficient.
根据单元信息、单元内的位置信息以及与其他部件的干扰信息，在实际中间体处分配对象组成一个抽象的house，进行部件拾取。与所分配的对象相对应，根据周围的条件输出MIM，并选择每个数字的数字或字母。中间体到对象的转换非常有效地实现了MIM s，否则就需要复杂的判断。外墙顶(MIM的8位数字)配置如图10所示。外墙a的上面有一个外墙，所以上面的下一部分是外墙。没有外墙，也没有单元，只有屋顶在外墙b的顶部，所以下一部分是屋顶。这个信息和其他周围情况，包括下一部分的干扰信息，需要识别具体的MIM。类似地，根据单元和其他部件确定其他数字，如底部下的下一个部分或开口，这样，在由虚拟空间中的对象组成的建模房屋中，对象的相互位置变得清晰，可以准确、有效地识别MIM s。此外，通过提供清晰的部分匹配图像，对象使编程更容易。此外，可视化的物体使部分爆炸非常有效。
4.2.2 Property inheritance from “object” to parts About 10 new Heim models and about 400 modifications/improvements are introduced annually. It is necessary to modify or add to the program responding to such changes, by exactly defining the alteration work. It means the program must be durable for alteration or addition. HAPPS program is made durable to alteration, by providing inherent relation between “objects” and subordinate parts. This relation enables to write just the additional changesless what is written in the superordinate program, minimizing the writing volume. It is easy to find affected points, which fact minimizes forgets and lowers error rate of program. For example, if a new color is added to the house colors, it is given as an attribute of whole house. This information is needed for exterior wall, openings, balcony etc., to be exploded to parts, however, this attribute of wall color is not given to “objects” of these intermediates but it is inherited from the house attributes. In case of addition or change of wall color, modification of program is necessary only in the house information. The inheritance plays a role to reduce writing volume and error rate of modification. 4.3 Application scope of HAPPS information Each “object” of HAPPS has location information of own intermediate and interfacing information to neighboring intermediates. These informations are also used for parts ordering and production instructions. Integration of information from HAPPS and information of the production scheduling will produce instructions to workers and machines, in binary or printed form.
4.2.2客体到局部的财产继承每年引进约10个new Heim车型，约400个改造/改善项目。有必要通过准确定义变更工作来修改或添加到程序中以响应这些变更。它意味着程序必须是持久的修改或增加。HAPPS程序通过提供对象和从属部分之间的固有关系，使更改变得持久。这种关系使我们能够只编写额外的更改，而不需要对上级程序中所写的内容进行修改，从而最小化写入量。该方法易于发现受影响的点，使程序的遗忘率和错误率降到最低。例如，如果将一个新颜色添加到房子的颜色中，它将作为整个房子的属性。外墙、开口、阳台等都需要这些信息，这些信息被分解成各个部分，然而，墙壁颜色的属性并没有赋予这些中间物，而是继承了房子的属性。如需增加或改变墙壁颜色，只需要对房屋信息进行修改。继承可以减少写量和修改的错误率。HAPPS信息的应用范围HAPPS的每个对象都有自己的中间物的位置信息，以及与相邻中间物的接口信息。这些信息也用于零件订购和生产说明。来自HAPPS的信息和生产调度信息的集成将产生二进制或打印形式的工人和机器指令。
Fig. 11 Application of HAPPS information in exterior wall installation
图11 HAPPS信息在外墙安装中的应用
Such function of HAPPS enables just-in-time, in-right-quantity feed of parts to assembly lines. As parts can be lined up in order of consumption, convenient environment can be provided for line workers who can just pick up the part at the end of lineup (Fig. 11)
HAPPS的这一功能使零部件能够及时、准确地送到装配线上。由于零件可以按消费顺序排列，可以为线工提供方便的环境，线工只需在排线结束时领取零件即可(图11)。
5. Efficiency and accur acy of HAPPS
5. 效率和幸福的准确性
5.1 Parts exploding rate and time consumption in HAPPS We reported the HAPPS above, however, we use other systems for parts explosion as well. HAPPS cover all the important parts which consist 70% of all parts of a house, including structural frames. HAPPS parts explosion takes 1 to 1,5 hour per house depending on the size and spec., starting from the input of floor plan and ending in the checking review. Total hours of parts explosion of a house is 5 to 6 hours.
我们报告了上述的HAPPS，但是我们也使用了其他的系统来进行零件爆炸。HAPPS覆盖了所有重要的部分，这些部分占了房子所有部分的70%，包括结构框架。根据房屋的大小和规格，每栋房屋的HAPPS零件爆炸需要1到1.5个小时，从平面图的输入开始，到审核结束。房屋部件爆炸的总时间是5到6个小时。
5.2 Accuracy of parts explosion in HAPPS HAPPS program is released once a month as a principle, corresponding to peaks of production. The system is checked by the input of about 70,000 test floor plans, before the release. If a model change takes place, current MIM’s are checked for malfunctioning which may be caused by the program change. If a model is added, test floor plans are also added to make sure the program puts correct solutions out. If a new series of Heim is launched, simulation check is conducted before the release. Rate of correct answer of MIM pickup is about 99,5% in simulations. The error rate in actual operation in 2005 was 0,017 errors per house, being calculated from 223 errors in about 13,000 houses.
HAPPS程序中零件爆炸的准确性以每月发布一次为原则，对应生产高峰期。该系统是通过检查输入约70000试验楼层平面图，然后发布。如果发生模型更改，则检查当前的MIM是否出现可能由程序更改引起的故障。如果添加了一个模型，还会添加测试层计划，以确保程序给出正确的解决方案。如果启动一个新的Heim系列，则在发布之前进行仿真检查。在仿真中，MIM拾取的正确率约为99.5%。2005年实际操作的错误率是每栋房屋0.017个错误率，这些错误率是根据13000栋房屋的223个错误率计算出来的。
6. Futur e plan
6. 未来计划
HAPPS has been very helpful to increase accuracy of part pickup and to decrease picking time, thus contributing to the efficiency of part handling. We plan to further minimize the error rate by improving the definition of MIM and the parts grouping method. We intend to extend the application scope of HAPPS as well.
HAPPS对提高零件拾取精度，减少拾取时间，提高零件搬运效率有很大帮助。我们计划通过改进MIM的定义和部件分组方法来进一步降低错误率。我们还打算扩展HAPPS的应用范围。