Dynamic Collision Detection Using Space Partitioning

1990 ◽  
Author(s):  
M. A. Ganter ◽  
B. P. Isarankura
Keyword(s):  
Collision Detection ◽  
Computation Time ◽  
Local Region ◽  
Detection Time ◽  
Space Partitioning ◽  
Worst Case ◽  
Simulated Environment ◽  
Time Required ◽  
Six Degree Of Freedom ◽  
Partitioning Technique

Abstract A technique termed space partitioning is employed which dramatically reduces the computation time required to detect dynamic collision during computer simulation. The simulated environment is composed of two nonconvex polyhedra traversing two general six degree of freedom trajectories. This space partitioning technique reduces collision detection time by subdividing the space containing a given object into a set of linear partitions. Using these partitions, all testing can be confined to the local region of overlap between the two objects. Further, all entities contained in the partitions inside the region of overlap are ordered based on their respective minimums and maximums to further reduce testing. Experimental results indicate a worst-case collision detection time for two one thousand faced objects is approximately three seconds per trajectory step.

Dynamic Collision Detection Using Space Partitioning

1993 ◽  
Vol 115 (1) ◽  
pp. 150-155 ◽  
Author(s):  
M. A. Ganter ◽  
B. P. Isarankura
Keyword(s):  
Computer Simulation ◽  
Collision Detection ◽  
Computation Time ◽  
Local Region ◽  
Detection Time ◽  
Space Partitioning ◽  
Simulated Environment ◽  
Time Required ◽  
Six Degree Of Freedom ◽  
Partitioning Technique

A technique termed space partitioning is employed which dramatically reduces the computation time required to detect dynamic collision during computer simulation. The simulated environment is composed of two nonconvex polyhedra traversing two general six-degree-of-freedom trajectories. This space partitioning technique reduces collision detection time by subdividing the space containing a given object into a set of partitions. Using these partitions, all testing can be confined to the local region of overlap between the two objects. Further, all entities contained in the partitions inside the region of overlap are ordered based on their respective minimums and maximums to further reduce testing.

An Octree Algorithm for Dynamic Interference Detection Using Space Partitioning

1996 ◽  
Author(s):  
Yongxiang Yu ◽  
Minghua Wu ◽  
Ji Zhou
Keyword(s):  
Collision Detection ◽  
Computation Time ◽  
Interference Detection ◽  
Space Partitioning ◽  
Time Consumption ◽  
Dynamic Interference ◽  
Partitioning Technique

Abstract This paper presents an octree algorithm for collision and interference detection using space partitioning technique. The technique greatly reduces the computation time consumed in dynamic collision detection during simulation progress. The simulated objects are represented in hierarchically decomposed octrees. Under this technique, the checking space can be partitioned according to the geometric dependence of two octrees, so that the relations (overlap or separate) among the nodes in the octrees can be determined directly. Since heuristic calculation is excluded from the algorithm, the time consumption for collision detection is greatly reduced.

scholarly journals AN EXPERIMENTAL ANALYSIS OF SPATIAL INDEXING ALGORITHMS FOR REAL TIME SAFETY CRITICAL MAP APPLICATION

2021 ◽  
Vol V-4-2021 ◽  
pp. 41-48
Author(s):  
F. Çetin ◽  
M. O. Kulekci
Keyword(s):  
Data Structure ◽  
Real Time ◽  
Data Structures ◽  
Spatial Indexing ◽  
Space Partitioning ◽  
Worst Case ◽  
Real Time System ◽  
Safety Critical ◽  
Range Search ◽  
Partitioning Technique

Abstract. This paper presents a study that compares the three space partitioning and spatial indexing techniques, KD Tree, Quad KD Tree, and PR Tree. KD Tree is a data structure proposed by Bentley (Bentley and Friedman, 1979) that aims to cluster objects according to their spatial location. Quad KD Tree is a data structure proposed by Berezcky (Bereczky et al., 2014) that aims to partition objects using heuristic methods. Unlike Bereczky’s partitioning technique, a new partitioning technique is presented based on dividing objects according to space-driven, in the context of this study. PR Tree is a data structure proposed by Arge (Arge et al., 2008) that is an asymptotically optimal R-Tree variant, enables data-driven segmentation. This study mainly aimed to search and render big spatial data in real-time safety-critical avionics navigation map application. Such a real-time system needs to efficiently reach the required records inside a specific boundary. Performing range query during the runtime (such as finding the closest neighbors) is extremely important in performance. The most crucial purpose of these data structures is to reduce the number of comparisons to solve the range searching problem. With this study, the algorithms’ data structures are created and indexed, and worst-case analyses are made to cover the whole area to measure the range search performance. Also, these techniques’ performance is benchmarked according to elapsed time and memory usage. As a result of these experimental studies, Quad KD Tree outperformed in range search analysis over the other techniques, especially when the data set is massive and consists of different geometry types.

scholarly journals Novel, low power, nonlinear dilatation and erosion filters realized in the CMOS technology

2015 ◽  
Vol 28 (2) ◽  
pp. 237-249 ◽  
Author(s):  
Rafał Długosz ◽  
Andrzej Rydlewski ◽  
Tomasz Talaśka
Keyword(s):  
Binary Tree ◽  
Delay Line ◽  
Cmos Technology ◽  
Analysis Procedure ◽  
Subsequent Stage ◽  
Detection Time ◽  
Digital Signals ◽  
Case Scenario ◽  
Worst Case ◽  
Binary Tree Structure

In this paper we propose novel, binary-tree, asynchronous, nonlinear filters suitable for signal processing realized at the transistor level. Two versions of the filter have been proposed, namely the dilatation (Max) and the erosion (Min) one. In the proposed circuits an input signal (current) is sampled in a delay line, controlled by a multiphase clock. In the subsequent stage particular samples are converted to 1-bit digital signals with delays proportional to the values of these samples. In the last step the delays are compared in digital binary-tree structure in order to find either the Min or the Max value, depending on which filter is used. Both circuits have been simulated in the TSMC CMOS 0.18?m technology. To make the results reliable we applied the corner analysis procedure. The circuits were tested for temperatures ranging from -40 to 120?C, for different transistor models and supply voltages. The circuits offer a precision of about 99% at a typical detection time of 20 ns (for the Max filter) and 100 ns for the Min filter (the worst case scenario). The energy consumed per one input during a single calculation cycle equals 0.32 and 1.57 pJ, for the Max and Min filters, respectively.

scholarly journals Data (Video) Encryption in Mobile devices

2017 ◽  
Vol 2 (3) ◽  
pp. 32-39
Author(s):  
Aya Khalid Naji ◽  
Saad Najim Alsaad
Keyword(s):  
Elliptic Curve ◽  
Mobile Devices ◽  
Mobile Device ◽  
Elliptic Curve Cryptography ◽  
Computation Time ◽  
Video Encryption ◽  
Android Platform ◽  
Time Required ◽  
New Generation

In the development of 3G devices, all elements of multimedia (text, image, audio, and video) are becoming crucial choice for communication. The secured system in 3G devices has become an issue of importance, on which lot of research is going on. The traditional cryptosystem like DES, AES, and RSA do not able to meet with the properties of the new generation of digital mobile devices. This paper presents an implementation of video protection of fully encrypted using Elliptic Curve   Cryptography (ECC) on a mobile device. The Android platform is used for this purpose.  The results refer that the two important criteria of video mobile encryption: the short computation time required and high confidentially are provided.

An Adaptive Multiscaling Approach for Reducing Computation Time in Simulations of Articulated Biopolymers

2019 ◽  
Vol 14 (5) ◽  
Author(s):  
Ashley Guy ◽  
Alan Bowling
Keyword(s):  
Computational Cost ◽  
Time History ◽  
Computation Time ◽  
Coarse Graining ◽  
Integration Time ◽  
Dynamic Simulations ◽  
Equivalent Time ◽  
Time Histories ◽  
Time Required ◽  
Computational Resources

Microscale dynamic simulations can require significant computational resources to generate desired time evolutions. Microscale phenomena are often driven by even smaller scale dynamics, requiring multiscale system definitions to combine these effects. At the smallest scale, large active forces lead to large resultant accelerations, requiring small integration time steps to fully capture the motion and dictating the integration time for the entire model. Multiscale modeling techniques aim to reduce this computational cost, often by separating the system into subsystems or coarse graining to simplify calculations. A multiscale method has been previously shown to greatly reduce the time required to simulate systems in the continuum regime while generating equivalent time histories. This method identifies a portion of the active and dissipative forces that cancel and contribute little to the overall motion. The forces are then scaled to eliminate these noncontributing portions. This work extends that method to include an adaptive scaling method for forces that have large changes in magnitude across the time history. Results show that the adaptive formulation generates time histories similar to those of the unscaled truth model. Computation time reduction is consistent with the existing method.

A simplified approach for thermal elastohydrodynamic lubrication analysis of circular contacts using realistic lubricant properties

2018 ◽  
Vol 232 (12) ◽  
pp. 1618-1632
Author(s):  
Puneet Katyal ◽  
Punit Kumar
Keyword(s):  
Mathematical Models ◽  
Point Contact ◽  
Elastohydrodynamic Lubrication ◽  
Computation Time ◽  
Fluid Temperature ◽  
Simplified Approach ◽  
Lubrication Film ◽  
Isothermal Case ◽  
Lubrication Characteristics ◽  
Time Required

Thermal effect in elastohydrodynamic lubrication has been the subject of extensive research for several decades. The focus of this study was primarily on the development of an efficient numerical scheme to deal with the computational challenges involved in the solution of thermal elastohydrodynamic lubrication model; however, some important aspects related to the accurate description of lubricant properties such as viscosity, rheology, and thermal conductivity in elastohydrodynamic lubrication point contact analysis remain largely neglected. A few studies available in this regard are based upon highly complex mathematical models difficult to formulate and execute. The end-users may not have the specialized skill, knowledge, and time required for the development of computational codes pertaining to these models. Therefore, this paper offers a very simple approach to determine the distribution of mean fluid temperature within an elastohydrodynamic lubrication film. While it is an approximate method, it yields reasonably accurate results with only a little increase in computation time with respect to the isothermal case. Moreover, it can be added as a small module to any existing isothermal algorithm. Using this simplified thermal elastohydrodynamic lubrication model for point contacts, this work sheds some light on the importance of accurate characterization of the lubricant properties and demonstrates that the computed thermal elastohydrodynamic lubrication characteristics are highly sensitive to lubricant properties. It also emphasizes the use of appropriate mathematical models with experimentally determined parameters to account for the correct lubricant behavior.

A Method for Simultaneously Satisfying Important Constraints and Dependencies for Many Different Types of Processes in Embedded Real-Time Systems

2011 ◽  
Author(s):  
Jia Xu
Keyword(s):  
Real Time ◽  
Computation Time ◽  
Real Time Systems ◽  
Worst Case ◽  
Release Times ◽  
Different Types ◽  
High Assurance ◽  
Run Time ◽  
Soft Deadline ◽  
Time Systems

In most embedded, real-time applications, processes need to satisfy various important constraints and dependencies, such as release times, offsets, precedence relations, and exclusion relations. Embedded, real-time systems with high assurance requirements often must execute many different types of processes with such constraints and dependencies. Some of the processes may be periodic and some of them may be asynchronous. Some of the processes may have hard deadlines and some of them may have soft deadlines. For some of the processes, especially the hard real-time processes, complete knowledge about their characteristics can and must be acquired before run-time. For other processes, prior knowledge of their worst case computation time and their data requirements may not be available. It is important for many embedded real-time systems to be able to simultaneously satisfy as many important constraints and dependencies as possible for as many different types of processes as possible. In this paper, we discuss what types of important constraints and dependencies can be satisfied among what types of processes. We also present a method which guarantees that, for every process, no matter whether it is periodic or asynchronous, and no matter whether it has a hard deadline or a soft deadline, as long as the characteristics of that process are known before run-time, then that process will be guaranteed to be completed before predetermined time limits, while simultaneously satisfying many important constraints and dependencies with other processes.

Sign in / Sign up

Export Citation Format

Share Document