Generic representation of 3D motion paths in dynamic animations of simulated construction processes

The presented research investigated generic and scalable techniques to accurately represent 3D motion paths in dynamic animations of operations simulated using Discrete-Event Simulation. The work designed and implemented methods that can be used to 1) define and manipulate arbitrarily-shaped trajectories to represent accurate 3D motion paths of virtual simulation objects, and 2) compute the precise three-dimensional spatial configuration of virtual simulation objects when they travel on defined paths. In order to address the problem of describing the accurate motion of simulation objects on realistic paths, the research investigated the requirements of two key technologies: 1) A mathematical representation for defining arbitrarily complex curves that can, by manipulating only high-level interaction parameters, be locally and/or globally edited to describe a realistic motion trajectory, and 2) A geometric basis to guide the computation of a simulation object's correct 3D orientation as it travels on an arbitrarily uneven virtual terrain surface. In order to achieve the first objective, the research investigated a technique of producing a general class of interpolating cubic splines whose shape can be locally or globally controlled by modifying three high-level control parameters. In addition, by implementing an innovative virtual terrain-following algorithm, a computation scheme was designed that correctly calculates and portrays the orientation of simulation objects along all three axes (yaw, pitch, and roll) as they travel inside animated 3D virtual worlds. The designed animation methods were implemented in a software tool called PathFinder that integrates as an add-on with the VITASCOPE visualization system. (c) 2007 Elsevier B.V. All rights reserved.