Incorporating free-form features in aesthetic and engineering product design: State-of-the-art report

Abstract

International audienceThe use of free-form shapes has become mainstream to design complex products that have to fulfil engineering requirements as well as aesthetic criteria. Even if today’s CAD systems can easily represent free-form shapes by means of NURBS surfaces, their definition and modification still require a deep knowledge and a great skill in the manipulation of the underlying mathematical models. The implemented free-form shapes design operators are time consuming and do not enable fast modifications. To overcome these limits, some researches have been undertaken to try to adapt the feature concept, successfully adopted for the design of regular shapes, in the free-form domain. It gives rise to a set of free-form features modelling strategies. This paper gathers together the state-of-the-art of these advances. The various approaches are depicted and compared with respect to a very precise set of criteria expressing the needs in aesthetic and engineering designs. The limits and future trends are presente

Semantic Evaluation and Deformation of Curves Based on Aesthetic Criteria

“…; consequently, features are intended as complex high level entities that allow a faster creation and modification of the geometric model. In literature, it is possible to find several studies focusing on the user interactions with shape product through free-form features [12]; there are various meaningful proposal for classification of free-form features [2][7] [16], and several interesting works [13][18] dealing with the shape modification by features but they are hardly taking into account aesthetic information; only few consider aspects, such as brand character or emotional feeling but are very peculiar to specific products and not generally applicable. Defining a strict link between geometric characteristics and aesthetic features is not immediate due to the multitude of the possible shapes and to the fuzziness of the concept of aesthetics.…”

A multi-perspective dynamic feature concept in adaptive NC machining of complex freeform surfaces

“…Commercial surface modelling tools are time-consuming and do not enable fast modifications for freeform surfaces, and feature technology is increasingly used to improve this [20]. In typical solid modelling methods, features are defined by a composition of simple geometric primitives like planes and cylinders which can be modified through parameters like length or width.…”

Processing Free Form Objects within a Product Development Process Framework

“…They reflect the application domain needs and characteristics. Considering the aesthetic and engineering design of products, four main categories of criteria have been identified [37]:…”

“…To provide a product description in terms of the various PDP activities, feature recognition strategies have been developed [46,31,28], and are mandatory when evolving from one process to another in a PDP because each process or task defines a specific context and often requires specific features. To carry FIGURE 1.12: Features classification based on the concept of level of control [37].…”