A Knowledge-Integrated Virtual Reality Machining Laboratory for Innovative Undergraduate Education

在涉及机械加工的本科制造课程教学中，一个常见的问题是难以安排适当的机械加工实验，原因有很多，例如：实验室设施有限，技术人员支持不足，班级规模大，举办昂贵实验的资金有限，以及安全考虑。缺乏对机械加工的实际了解会削弱这门课程的学习效果。该项目的目标是开发一个集计算机图形动画、工艺知识和预测加工模型于一体的虚拟现实(VR)加工实验室。具体的目标是帮助学生获得重要的动手加工经验，增强他们对加工原理的物理理解，最大限度地提高他们的潜在学习能力。在这样的虚拟环境中，所有学生都有一个一对一的机会，通过选择不同的工艺参数，对各种机床(包括常规机床和数控机床)进行物理操作，并在线观察和研究模拟的动态加工性能。该项目的意义在于，它具有显著的性价比、知识集成的交互式学习环境、对各种加工操作的极大灵活性以及基于C语言的软件易于移植的优势，可以作为未来机械加工实验室的国家样板。研究结果对其他高校建立类似体系具有很大的吸引力，并对当前制造业课程的教学实践产生重大影响。虚拟现实系统在不同开发阶段的有效性将通过课程ME322制造工艺(每学期提供)的连续四个学期进行评估。作为未来机械加工实验室的国家典范，拟议项目的结果将通过会议、出版物和万维网公布。

A common problem in teaching undergraduate manufacturing courses involving machining is the difficulty to arrange appropriate machining experiments for a number of possible reasons such as: limitations on laboratory facilities, insufficient support of technicians, large size of class, limited funds for running the costly experiments, and safety considerations. Lack of physical understanding about the machining undermines the learning effectiveness in this course. The goal of the proposed project is to develop a virtual reality (VR) machining laboratory integrated with computer graphics animation, process knowledge and predictive machining models. The specific objectives are to help students in obtaining important hands-on" machining experience, enhance their physical understanding of machining principles, and promote their latent learning capability to the maximal possible extent. In such a virtual environment, all the students have a ' one-to-one" opportunity to "physically" operate various kinds of machines (both conventional and CNC) on their own and observe and study the on-line simulated dynamic machining performance by choosing different process parameters. The significance of the proposed project is that it can be used as a national model for future machining laboratories with the advantages of significant cost-effectiveness, knowledge-integrated interactive learning environment, great flexibility for various machining operations and, C-based software for easy portability. The results should be very attractive to other colleges for setting up a similar system and should have a significant impact on current teaching practices of manufacturing courses. The effectiveness of the VR system at different development stages will be evaluated through four consecutive teaching semesters of the course ME322 Manufacturing Processes (offered every semester). As a national model for future machining laboratories, the results of the proposed project will be publicize d through conferences, publications and the World Wide Web.