Sector meshing and neighbor searching for object interaction simulation

Abstract

Methods for computer-implemented simulation for the interaction of two or more objects are provided. Data describing particles that represent each of the objects is generated from geometric data for objects. The data for each particle describes a mass density, velocity and energy at a position of the corresponding object. The particles are grouped into sectors to define a computational mesh comprising a plurality of sectors, wherein each sector is a volume region at a position in space in which particles associated with the objects may reside. For each of a plurality of select particles, so called neighboring particles are determined that are within a region of influence with respect to a select particle. Computations are performed based on laws of conservation of mass, energy and momentum to produce updated values for mass, velocity, energy, pressure, stress and position for the particles at each of a plurality of time steps. According to one aspect, when determining neighboring particles for a given select particle, a search is made through a limited or bounded volume region with respect to the select particle that consists of the region of influence for the select particle at the previous time step and within those sectors in contact with or bordering the region of influence at the previous time step. According to another aspect, the plurality of select particles are identified as those particles that reside in an active sector, wherein an active sector is a sector that contains, or is adjacent to a sector that contains, particles that is actively involved in the engagement between the two objects. For example, an active sector is a sector that contains, or is adjacent to a sector that contains, at least one particle that has a velocity, pressure or stress greater than a corresponding predetermined amount.

Description

FIELD OF THE INVENTION[0001]The present invention relates to computer simulations of physical phenomena, and more particularly to methods for reducing the amount of computations necessary during a particle-system based computer simulation of the engagement of two or more objects.BACKGROUND OF THE INVENTION[0002]Computer simulations for experiments involving the impact of one object with another object have widespread applications. For example, automobile manufacturers use such simulations in designing safer vehicles. In a totally different technology field, scientist uses such simulations to study the effectiveness of a missile destroying a moving or stationary target. Regardless of the particular application, it is an overall goal to design a computer simulation that can accurately produce data concerning possible outcomes of the physical phenomena of interest pertaining to two or more objects. However, there is a tradeoff between accuracy and simulation run time. Generally, the mo...

AI Technical Summary

Benefits of technology

[0007]The particles are regrouped and neighboring particles are identified at each time step. By limiting the volume region which a search is made for neighboring particles, and by performing the neighbor search step only for particles in sectors that are “actively” involved in the engagement, the number of computations performed at a given time step is greatly reduced.

[0008]The computer simulation run time is significantly reduced by focusing computational resources on the particles that are most relevant to the engagement of the objects at a particular time step, therefore reducing the number of particles in the computational mesh at a given time step.

Problems solved by technology

However, there is a tradeoff between accuracy and simulation run time.

Generally, the more complex a simulation is in order to achieve better accuracy, the longer it takes for that simulation to run to completion.

In fact, very complex computer simulations, such as so-called “hydrocodes” can take several days or longer to execute on highly sophisticated models of certain physical events.

However, the reality is that at any given time step, not all of the particles in the system may have an active role in the engagement.

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