Relevant Papers

 

1. Rigid body dynamics for rock fall trajectory simulation (Paper presented at ARMA 2012 in Chicago)

2. Coefficient of restitution for rigid body dynamics modelling from onsite experimental data (Paper presented at Slope Stability 2013 in Brisbane - the first page is the ACG copyright page)

3. An Evaluation of Open Source Physics Engines for Use in Virtual Reality Assembly Simulations (A 2012 paper by Hummel et al. comparing the accuracy of Physics Engines - Trajec3D uses the Newton Game Dynamics engine that performed well in all accuracy tests)

 

 

Trajec3D Information

 

Trajec3D is a three-dimensional rigid body rock fall analysis program that can simulate the trajectory of volumetric bodies during free fall, bouncing, sliding and rolling. The body shape is selected from a toolbar and the size is a function of the selected geometry, mass and rock density. The physics interaction between materials is a function of the combined properties of the fall body and the impact surface, and three parameters are required:

 

• Coefficient of restitution (elasticity);

• Static friction angle;

• Dynamic friction angle.

 

Trajec3D is a modelling tool that enables the quick assessment of many scenarios to better understand potential trajectories that dislodged rocks could follow, the time it should take to reach areas of interest, and an estimate of the energy along the path. Trajec3D is a simplification of reality with the aim to investigate different possibilities, and not a precise engineering design package.

 

This Beta-version of Trajec3D can be tested free of charge and feedback will be appreciated. Do not be discouraged if I am a bit slow to reply, as I am a full-time employee and travel frequently. My time is thus limited and responses will be managed between other responsibilities.

 

 

Getting Started Instructions
 

Trajec3D is simple to use when the following is known:

• Import a pit shell as a DXF triangulation file (NOT "Advanced DXF" or "DWG" files).

• Pit shells can be loaded with "Load - DXF pit triangulation" or by dragging-and-dropping a DXF-file into the scene window.

• Left mouse button rotates the scene.

• Middle mouse button pans the scene.

• Right mouse button or mouse wheel zooms the scene.

• Double click on any mesh to change the rotation point.

• Double click on empty space to centre the pit in the middle of the view area.

• Some buttons act as toggle switches, with a turquoise button background indicating ON. Press the button again to toggle OFF and the background will change back to the default colour.

• When the "Start"-button is toggled to ON, the right button generates falling bodies as long as the button is pressed and the mouse cursor is on the pit mesh.

• Hovering the mouse over controls brings up short descriptions of their functionality.

• The information of a measurement line is written directly above the measurement line - zoom into the start of the line to read the length and dip values.

• When the graph functionality is activated, hover the mouse cursor over the trajectory of interest to display the graph. The values of the segment of the trajectory directly below the mouse pointer will be displayed above the graph lines.

• When deleting individual fall bodies or path trajectories, hover the mouse over the object of interest and press the "delete" keyboard button.