Highly Flexible and Intuitive Computer-Aided Design Modeling

计算机辅助设计（CAD）已经成为产品设计的主导工业实践。虽然相当健壮和通用，但目前的商业CAD软件使用严格的基于参数的建模方案。设计师必须学会遵循一个非常具体的技术模型的创建和修改。设计师不是专注于塑造整体模型的几何形状，而是通过指定单个几何特征的尺寸和约束特征之间的关系来创建模型。诚然，这是一种创建CAD模型的强大方法，因为它确保了所创建模型的准确数字表示。然而，随着新技术的出现，几十年的CAD建模方案面临着巨大的压力。具体来说，最新的3D激光扫描仪和3D相机可以轻松地从物理对象表面捕获大量数据点。这些3D数字化设备将极大地促进从物理对象直接创建复杂的CAD模型。近年来，虚拟现实或三维可视化技术也在迅速发展。具有3D用户界面的原型CAD站已经被披露并获得了大量媒体报道。这些先进的3D技术将继续推动CAD建模向高度灵活和直观的环境发展。遗憾的是，目前基于参数的建模方案过于僵化，无法充分利用新的3D技术，成为整体技术进步的拖累。******提出的研究计划旨在从当前基于参数的方案到高度灵活的混合方案对CAD建模进行根本性的改变。未来的发展将彻底改变设计师如何与CAD系统交互，以创建和修改CAD模型。复杂的CAD模型可以直接和容易地使用3D扫描仪/相机创建。在虚拟现实3D平台上，设计师可以进行直观的建模操作，目前只有部分可用。CAD模型将以类似于塑造物理对象的方式直观地进行修改。典型的直观建模操作包括合并（类似于连接乐高积木），雕刻（类似于使用雕刻工具）和变形（类似于玩Play-Dohr）。然后，使用CAD的学习曲线将大大减少。由于使用直观的建模操作符可以轻松地修改CAD模型，设计师将能够通过迭代设计建模过程快速完成设计。因此，整体设计周期时间将大大缩短，这将明显增加加拿大工业的竞争力。虚拟现实3D平台正在建设中，并将在未来几年得到广泛应用。由于多年来在这一重要领域的研究和开发，加拿大将被认为是兼容CAD建模技术的领导者。

Computer-Aided Design (CAD) has been the dominant industrial practice for product design. While reasonably robust and versatile, current commercial CAD software uses a rigid parameter-based modeling scheme. Designers have to learn to follow a very specific technique for model creation and modification. Rather than focusing on shaping the overall model geometry, designers create models by specifying dimensions to individual geometric features and constraining inter-feature relationships. This admittedly is a powerful method to create CAD models since it ensures accurate digital representation of the created model. However, as new technologies emerge, the decades-old CAD modeling scheme is under significant stress to keep up. Specifically, the latest 3D laser scanners and 3D cameras can easily capture massive data points from a physical object surface. These 3D digitizing devices would greatly facilitate direct creation of complex CAD models from physical objects. Virtual reality or 3D visualization technologies are also advancing rapidly in recent years. Prototype CAD stations with 3D user interfaces have already been disclosed and received much media coverage. These advanced 3D technologies will continue to power the evolution of CAD modeling into a highly flexible and intuitive environment. Unfortunately, the current parameter-based modeling scheme is too rigid to fully utilize the novel 3D technologies and has become a drag to the overall technological advancement.******The proposed research program aims to make fundamental changes to CAD modeling from the current parameter-based scheme to a highly-flexible hybrid scheme. The prospective development will revolutionize how designers interact with the CAD system to create and modify CAD models. Complex CAD models can be directly and easily created using 3D scanners/cameras. On a virtual reality 3D platform, designers can carry out intuitive modeling operations that are only partially available today. CAD models are to be modified intuitively in ways similar to shaping physical objects. Typical intuitive modeling operators include merging (similar to connecting LEGOr blocks), sculpting (similar to using a sculpting tool), and deforming (similar to playing with Play-Dohr). The learning curve to use CAD will then be drastically reduced. With the ease of modifying CAD models with the intuitive modeling operators, designers will be able to quickly finalize their design through the iterative design modeling process. The overall design cycle time will thus be significantly reduced and this will evidently add to the competitiveness of Canadian industries. Virtual reality 3D platforms are being built and will become widely used in the coming years. Canada will then be recognized as the leader in the compatible CAD modeling technologies due to years of prior research and development in this important area.