The Engineering Sketch Pad: A Solid-Modeling, Feature-Based, Web-Enabled System for Building Parametric Geometry

Abstract

Within the multidisciplinary analysis and optimization community, there is a strong need for browser-based tools that provide users with the ability to visualize and interact with complex three-dimensional configurations. This need is particularly acute when the designs involve shape-and/or feature-based optimizations. Described herein is a family of open-sources software products that provides such a capability. At the top is a browser-based system, called the Engineering Sketch Pad (ESP), which provides the user the ability to interact with a configuration by building and/or modifying the design parameters and feature tree that define the configuration. ESP is built both upon the WebViewer (which is a WebGL-based visualizer for three-dimensional configurations and data) and upon OpenCSM (which is a constructive solid modeler; it in turn is built upon the EGADS and OpenCASCADE systems). Each of these open-source software components are described as well as the interactions amongst them.

Geometry Driven High Fidelity Stability Derivatives Obtained Using Automated CFD Analysis Process

“…Three sets of tools for automated analysis are being used: one for geometry creation, the second for mesh generation, and the third for fluid dynamics analysis. The first is geometry, and for this, Engineering Sketch Pad 10,12,13 (ESP) is being used. ESP uses OpenCASCADE 14 as the geometry kernel.…”

Algorithmic differentiation of the Open CASCADE Technology CAD kernel and its coupling with an adjoint CFD solver

“…Dannenhoffer and Haimes used the open-source CAD kernel Open CASCADE Technology (OCCT) to develop a fully-parametric, feature-based solid-modeling system with web-based user interface [9]. To obtain the derivatives they applied analytic differentiation to simple geometrical shapes (such as circles or cylinders), while finite differences are used for the more complex geometries [4].…”

Model Uncertainty: A Challenge in Nonlinear Coupled Multidisciplinary System Design

“…In this example problem, the geometry engine providing configuration information for analysis is Engineering SketchPad (ESP). 17 ESP links computer aided design (CAD) geometry representations with scripts for generating analysis geometry input files for a variety of programs. The geometry is defined via a set of primitives which are either blended using a cubic spline or ruled using linear interpolation to form surfaces.…”