Design evaluation and modification of mechanical systems in virtual environments

Design is one of the most important stages in the manufacturing cycle and influences all the subsequent stages of product development. In the context of today’s iterative design methodology, the modification of any design is a process involving many evaluations and improvements to the solutions chosen in earlier stages. For this purpose, in the most recent decade, 3D computer simulations have become common tools used within industry. Whilst virtual reality (VR) technology is seen as the interaction technology of the future, much of the current research in this area is carried out to explore the potential benefits and added value brought by the integration of this into standard software technologies currently used at various stages in manufacturing life cycle. A lot of attention has been given to exploring the usability and benefits of interactive VR for assembly planning, knowledge elicitation and design and simulation. However, little research has focussed on the analytical aspects of the design process, for example in the use of VR as an interface for simulation software in finite element methods and multi-body systems. This paper introduces research focussing on applications of virtual environments (VEs) for interactive design evaluation and modification adapted and used with standard simulation software. The use of such interactive visualisation offers the engineer more realistic real-time representations of the design and advanced facilities to interact with the model during the design process. While design evaluation is based mainly on visualisation; design modification requires interactive changes of the model during the simulation, and the interfaces described here highlights such applications. In this work, two software prototypes have been developed using VR technology. First, a software tool called design evaluation in virtual environments is presented together with an application in civil engineering to illustrate the mode of operation and added value of the use of an interactive visualisation environment. Linking the simulation software with the VE provides real time bi-directional communication of graphical information which can be successfully achieved even within the limits of current computer technology. The tool includes a suite of software modules and a user interface to facilitate the link between the simulation results and the VE. The second tool facilitates the design modification in virtual environments system by providing real time dynamic simulation. Two dynamic approaches are investigated in order to study the real time simulation issues in the context of design modification and system performance: the classic approach based on rigid interconnected bodies, and a new and novel approach developed by the authors based on particles dynamics. Both implementations have been tested and compared on a mechanism application under the same computing conditions. The research applications presented demonstrate the practicality, flexibility and versatility of the visualisation in virtual environment in design evaluation and modification. However, the computer efficiency whilst carrying out real time dynamic simulation is limiting the range of applications to models of moderate size; however, this is an improvement on previous similar applications.     

Supporting usability through software architecture

Software engineers should consider usability as a quality attribute in their architectural a designs. Usability determines how effectively and comfortably an end-user can achieve the goals that gave rise to an interactive system. It is an important attribute to consider during all phases of software design, but especially during architectural design because of the expense involved in adding usability aspects after users have tested the system. Since the 1980s, ongoing work on supporting usability through software architectural constructs has focused on the iterative design process for the user interface, which involves initial design, user testing, re-design to correct detected flaws, re-testing, and so on. The traditional software architectural response to repeated and expected modifications to the user interface is to use separation, encapsulation and information hiding to localize the user interface     

Virtual design of multiengineering electronics systems

The authors describe a virtual reality prototyping (VRP) and virtual product design approach that uses a modeling strategy to design, test, and evaluate concepts and products in advance-before creating any physical design models. Their design decisions reflect solutions and practices derived from systems engineering and software engineering research. Close competition has forced companies to focus on tailoring technological products to meet customer preferences in user interface design, usability, and appearance. Often, implementing new features has assumed less importance than creating an optimal product variation for different customer segments in international markets. Modern computer-based systems result from a multidomain development process, and organizing this work requires developers to communicate, cooperate, and coordinate effectively with nonengineering teams. Early linking of product development to other company operations supports this activity. Geographically dispersed development teams must communicate and coordinate effectively. Extending the use of interactive, functional, and photorealistic 3D product models into other company domains can facilitate effective business practices that cover the entire value chain, from simulated product idea to Web-based customer support of the final product. This wider adoption of the VRP technology and process offers ample scope for further research     

A structured methodology for comparative evaluation of user interface designs using usability criteria and measures

Previous research in software ergonomics has indicated the importance of evaluating the usability of computer user interfaces. This paper presents a quantitative basis for selecting from among multiple alternative interfaces relative to multiple criteria of usability concern. The proposed model consists of two main phases: the prescreening phase and the evaluation phase. The prescreening phase involves expert judgment-based assessment with qualitative criteria. The first phase uses absolute measurement analytic hierarchy process (AHP) to filter possible alternative interfaces to a reasonable subset. The evaluation phase involves user-based assessment such as user testing, with quantitative criteria. The objective of the second phase is to evaluate a subset of alternatives using objective measures and to select the best alternative. A set of criteria and measures for evaluating the usability of computer software designs is presented. The proposed methodology is demonstrated in the interface design of a database system used to analyze trip cases information of nuclear power plant.Relevance to industry

There is currently a focus on the usability of interactive computer software. Software developers, interface designers or human factors engineers often confront the task of comparative evaluation among systems, versions or interface designs. The proposed methodology provides practitioners with a structured approach to select the best interface based on usability criteria and measures.     

Design parameterization and tool integration for CAD-based mechanism optimization

This paper presents an open and integrated tool environment that enables engineers to effectively search, in a CAD solid model form, for a mechanism design with optimal kinematic and dynamic performance. In order to demonstrate the feasibility of such an environment, design parameterization that supports capturing design intents in product solid models must be available, and advanced modeling, simulation, and optimization technologies implemented in engineering software tools must be incorporated. In this paper, the design parameterization capabilities developed previously have been applied to support design optimization of engineering products, including a High Mobility Multi-purpose Wheeled Vehicle (HMMWV). In the proposed environment, Pro/ENGINEER and SolidWorks are supported for product model representation, DADS (Dynamic Analysis and Design System) is employed for dynamic simulation of mechanical systems including ground vehicles, and DOT (Design Optimization Tool) is included for a batch mode design optimization. In addition to the commercial tools, a number of software modules have been implemented to support the integration; e.g., interface modules for data retrieval, and model update modules for updating CAD and simulation models in accordance with design changes. Note that in this research, the overall finite difference method has been adopted to support design sensitivity analysis.     

无人物流车的车外屏人机界面设计研究

随着智能汽车和物流行业快速发展,产业结合促进了无人物流车的出现。为了提 高无人物流车的安全、效率和用户体验,对无人物流车的车外屏人机界面设计进行研究。首先 提出了基于无人物流车的人-车-环境关系理论,并且结合物流车的运行场景流程对车外屏人机 界面的设计需求进行了研究。在此基础上,对无人物流车的车外屏人机界面的信息架构、多通 道交互模式及界面设计进行了探讨和设计实践,并且对物品回收功能的初步原型设计进行了可 用性测试评估。测试结果显示初步的无人物流车车外屏交互原型逻辑流畅,可用性较高。调查 结果显示用户希望无人车定位准确,并且可以利用积分制来兑换物质奖励。研究表明车外屏人 机界面设计可以提高无人物流车的安全、效率和用户体验。对无人物流车的车外屏设计进行修 改和完善,并且经过测试迭代后,将会不断提升车外屏设计。     

Reconciling usability and interactive system architecture using patterns

Traditional interactive system architectures such as MVC [Goldberg, A., 1984. Smaltalk-80: The Interactive Programming Environment, Addison-Wesley Publ.] and PAC [Coutaz, J., 1987. PAC, an implementation model for dialog design. In: Interact’87, Sttutgart, September 1987, pp. 431-436; Coutaz, J., 1990. Architecture models for interactive software: faillures and trends. In: Cockton, G. (Ed.), Engineering for Human-Computer Interaction, Elsevier Science Publ., pp. 137-153.] decompose the system into subsystems that are relatively independent, thereby allowing the design work to be partitioned between the user interfaces and underlying functionalities. Such architectures extend the independence assumption to usability, approaching the design of the user interface as a subsystem that can designed and tested independently from the underlying functionality. This Cartesian dichotomy can be fallacious, as functionalities buried in the application’s logic can sometimes affect the usability of the system. Our investigations model the relationships between internal software attributes and externally visible usability factors. We propose a pattern-based approach for dealing with these relationships. We conclude by discussing how these patterns can lead to a methodological framework for improving interactive system architectures, and how these patterns can support the integration of usability in the software design process.     

The usability engineering life cycle

A practical usability engineering process that can be incorporated into the software product development process to ensure the usability of interactive computer products is presented. It is shown that the most basic elements in the usability engineering model are empirical user testing and prototyping, combined with iterative design. Usability activities are presented for three main phases of a software project: before, during, and after product design and implementation. Some of the recommended methods are not really single steps but should be used throughout the development process     

基于虚拟现实技术的建筑施工动态仿真研究

建筑施工过程是一个极其复杂、高度动态的过程,容易受到各种因素的干扰。建筑物的内部结构纷繁复杂,又相互牵连制约,造成建筑施工存在时间和空间上的复杂的逻辑关系。本文基于虚拟现实技术利用3DS Max软件来模拟建筑施工的主要施工环节,实现在虚拟环境中的建筑施工过程的动态仿真,并利用Virtools虚拟交互软件完成交互设计,实现多角度、全方位观察建筑模型。这一研究对优化建筑设计和保障建筑施工安全将有较大的意义和促进作用。     

UPIM:以用户为中心的笔式交互系统设计

笔式用户界面是Post-WIMP界面的一种重要形态,有自然、易学、易用等潜在性优点,但是在开发笔式交互系统时,以应用为中心的设计方法无法保证笔式用户界面继续拥有这些优点．为此,首先分析了软件设计的交流模型,在此基础上提出了一种以用户为中心的笔式交互系统的设计方法,并结合科学跳水训练管理系统对该方法进行了详细描述．从实际应用系统的评估结果来看,该设计方法在提高笔式交互系统的可用性方面非常有效．     

The cobbler's children: usability in the lab

Software and product designers regularly wrestle with the usability of their creations in user studies laboratories. The laboratories themselves, however, often languish for lack of the same scrutiny with respect to their own usability. In this article, we trace our efforts toward making a truly usable user studies laboratory. Our lab serves many purposes and many individuals, each requiring a slightly different configuration of equipment. The challenge was to design a user studies environment that would provide 'instant' configurations, obviating the need for users to connect components by hand. Toward this end, we purchased equipment that could be controlled directly or indirectly by a computer and designed the wiring plant to all run through a matrix switcher, also under computer control. Upon this technology, we designed a user interface in HyperCard that automatically configures the lab and provides the interface controls required for any one of a set of specific pre-designed tasks that the user may select. The interface also permits the user to customize and save sets of configurations and controls by copying and pasting among cards and also to create novel configurations by manipulating the matrix controller's software switches one by one.     

Model-Driven Interactive System Design for Therapy Robots

Physiotherapy using intelligent robots is emerging as a new approach to recovery for many stroke patients. Although therapy robots have a strong potential in dealing with therapeutic and other medical applications, they have not been fully utilized in everyday therapy activities due to concerns over safety and the lack of friendly robot user/patient interaction models. From the viewpoint of software engineering, a user-centred design based on UML (Unified Modelling Language) has been known to be one of the best solutions to satisfy usability since the design process relies heavily on the analysis of users and their tasks to reach their goals. Therefore, a model-driven approach to interactive system design via UML for therapy robots is needed to make them usable in the real world. This paper proposes such approach and introduces a new graphical notation that describes user interface elements and the methods of connection with hardware/software objects. With the proposed abstract interaction models, prototyping interactive systems can be made faster and allows for their evaluation by users and system developers before implementation in order to improve usability from the perspectives of users and system developers.     

Structural planning and implementation of a microprocessor-based human-machine interface in a steam-explosion process application

In this paper, small-scale microprocessor-based human-machine interface (HMI) and programmable logic controller (PLC) standard software libraries are applied to plan, design, implement, and construct models for creating the modular application software. The graphical user interface (GUI) functions used in a specific biomass steam-explosion process, intended to be integrated with the PLC device for HMI, thereby providing excellent GUI-based supervision and control functions. Reviewing these specific case study results, we find that the major advantage is maximum system operating performance at minimum cost. Also, the GUI/HMI operation effectively provides user-friendly and reliable interactions. This GUI/HMI approach is a very cost-effective technique.     

Using task analysis to improve usability of fatigue modelling software

The design of any interactive computer system requires consideration of both humans and machines. Software usability is one aspect of human–computer interaction that can benefit from knowledge of the user and their tasks. One set of methods for determining whether an application enables users to achieve their predetermined goals effectively and efficiently is task analysis. In the present study, a task analysis was applied to the graphical user interface of fatigue modelling software used in industry. The task analysis procedure allowed areas of usability improvement to be identified and then addressed with alternate interface prototypes. The present method of task analysis illustrates a practical and efficient way for software designers to improve software usability, user effectiveness and satisfaction, by involving users in the design process.     

The cobbler's children: usability in the lab

Abstract

Software and product designers regularly wrestle with the usability of their creations in user studies laboratories. The laboratories themselves, however, often languish for lack of the same scrutiny with respect to their own usability. In this article, we trace our efforts toward making a truly usable user studies laboratory. Our lab serves many purposes and many individuals, each requiring a slightly different configuration of equipment. The challenge was to design a user studies environment that would provide ‘instant’ configurations, obviating the need for users to connect components by hand. Toward this end, we purchased equipment that could be controlled directly or indirectly by a computer and designed the wiring plant to all run through a matrix switcher, also under computer control. Upon this technology, we designed a user interface in HyperCard that automatically configures the lab and provides the interface controls required for any one of a set of specific pre-designed tasks that the user may select. The interface also permits the user to customize and save sets of configurations and controls by copying and pasting among cards and also to create novel configurations by manipulating the matrix controller's software switches one by one.     

Monitoring computer users' behaviour in office environments

Monitoring computer users' behaviour to enhance the usability of software has become increasingly popular among the developers of computer products. One objective of this paper is to compare the use of a software monitoring technique with other field observation methods. It is argued that when contrasted against traditional observation techniques, the software monitor provides a more accurate and unobtrusive approach to collecting behavioural data on larger samples of individuals for longer periods of time than either participant observation or Thinking Aloud methodologies. A second objective is to demonstrate the application of software monitors on installed multi-user systems. Technical aspects of software monitor design are discussed, with emphasis on specific practical problems in monitor design and utilization when making the transition from the laboratory to an office environment. Data from two studies are presented. The first illustrates how a software monitor can be used to determine the impact and acceptance of various software packages in an integrated office automation product. The second study examines how software monitor data were used to modify the interface to a specific electronic mail facility.     

Mixed reality environment for learning sensing technology applications in Construction: A usability study

Mixed reality is gradually becoming ubiquitous and significant in education owning to the inherent benefits of active participation and tacit knowledge development in a safe and engaging environment. However, limited studies have explored design features that facilitate its use as a pedagogical tool in construction education, particularly in equipping students with experiential skills that are otherwise challenging to obtain due to resource constraints and limited access to construction sites. By evaluating eye tracking, usability questions, and think-aloud protocol data and verbal feedback, this study investigated the usability of a mixed reality environment designed for equipping construction engineering students with competencies for deploying sensing technologies on construction projects. Results revealed features such as accuracy of represented construction activities, quality of animations, and easy access to information and resources as important for designing efficient mixed reality learning environments. While the usability data suggested that the user interface was usable, eye tracking provided profundity on encountered difficulties with the user interface. Through concise outline and sequential design of the user interface, this study revealed that knowledge scaffolding can improve task performance in a mixed reality learning environment. This study adds value to existing literature, in particular by providing insights into the affordances of mixed reality environments that address the technological gap between the construction industry and construction engineering education. The mixed reality learning environment contributes to the cognitive apprenticeship theory through the use of game objects to develop procedural knowledge for addressing construction industry challenges with sensing technologies.     

A controlled empirical evaluation of a requirements abstraction model

Requirement engineers in industry are faced with the complexity of handling large amounts of requirements as development moves from traditional bespoke projects towards market-driven development. There is a need for usable and useful models that recognize this reality and support the engineers in a continuous effort of choosing which requirements to accept and which to dismiss off hand using the goals and product strategies put forward by management. This paper presents an evaluation of such a model that is built based on needs identified in industry. The evaluation’s primary goal is to test the model’s usability and usefulness in a lab environment prior to large scale industry piloting, and is a part of a large technology transfer effort. The evaluation uses 179 subjects from three different Swedish Universities, which is a large portion of the university students educated in requirements engineering in Sweden during 2004 and 2005. The results provide a strong indication that the model is indeed both useful and usable and ready for industry trials.     

弹性飞机模型降阶软件设计

针对弹性飞机模型降阶问题,对几种适合弹性飞机模型降阶的方法进行了研究,采用Matlab的GUI技术开发了模型降阶软件.该软件以交互式界面实现Matlab环境下的模型自动降阶,可供不同的弹性飞机模型选择适用的降阶方法,并可以根据降阶效果修改降价阶次.以一个高阶弹性飞机模型为例,进行模型降阶软件的仿真应用与分析,演示了交互式界面软件使用方便、简单易学的特点,使得对弹性飞机模型降阶的设计与仿真更加方便、直观,大大缩短了设计周期,具有一定的工程意义.     

HCI and business practices in a collaborative method for augmented reality systems

ContextEvery interactive system is composed of a functional core and a user interface. However, the software engineering (SE) and human–computer interaction (HCI) communities do not share the same methods, models or tools. This usually induces a large work overhead when specialists from the two domains try to connect their applicative studies, especially when developing augmented reality systems that feature complex interaction cores.ObjectiveWe present in this paper the essential activities and concepts of a development method integrating the SE and HCI development practices, from the specifications down to the design, as well as their application on a case study.MethodThe efficiency of the method was tested in a qualitative study involving four pairs of SE and HCI experts in the design of an application for which an augmented reality interaction would provide better user performance than a classic interactive system. The effectivity of the method was evaluated in a qualitative study comparing the quality of three implementations of the same application fragment (based on the same analysis model), using software engineering metrics.ResultsThe first evaluation confirmed the ease of use of our method and the relevance of our tools for guiding the design process, but raised concerns on the handling of conflicting collaborative activities. The second evaluation gave indications that the structure of the analysis model facilitates the implementation of quality software (in terms of coupling, stability and complexity).ConclusionIt is concluded that our method enables design teams with different backgrounds in application development to collaborate for integrating augmented reality applications with information systems. Areas of improvement are also described.