MATLAB: Need a guide for using vrtracer and/or 3D World Editor

3d world editorSimulink 3D Animationvrtrace

I was trying to use vrtrace for tracking an object in my simulation but cannot find a good document explaining how to use it. The specific problem that I am currently having is as follows:

I am not sure how to enable tracing of an object. I looked into the example 'vrtkoff_trace.mdl'. It seems like 'IS' mapping is required in the wrl file for the tracing option to be usable. (I am not sure if I am correct, but I believe so since translation of a marker node is set to "IS MarkerTranslation" in the vrtkoff_trace model's wrl file)

I tried to do that in my file as well, but when I right click similar nodes in my file, i get the "IS" option disabled. I don't know why it is disabled and how to tackle this issue.

A snapshot of the disabled option: http://i.imgur.com/8vB0dkg.png

If someone can guide me through this, it will be highly appreciated.

Thanks.

Best Answer

In most cases, there is no need to modify the virtual world you want to use for object tracing. So you don't need to care about the IS mappings, they are added automatically by the VR Tracer block.

Currently, you probably have a model that moves an object in a virtual world by sending the object's position signal computed by Simulink to the translation field of the enclosing Transform node of the object. All you need to do is to copy the VR Tracer block from the library to your model and connect the same position signal to the input of the block. Then, in the VR Tracer block parameters, you need to specify the parent transform node name relative to which the position is specified. If this is an absolute position, you leave the parent transform name empty (= relative to root).

You can also compare the vrtkoff and vrtkoff_trace examples. They use the same virtual world and also most of the Simulink model is the same, the only major difference is the added VR Tracer block in vrtkoff_trace. So the modification you need to do to your Simulink model is very similar to the changes between vrtkoff and vrtkoff_trace, and your virtual world probably does not need any change at all.

Related Solutions

MATLAB: How to group transforms in matlab’s Simulink 3D Animation v-realm builder

A few options that come to my mind are:

a. Open up the VRML file in a text editor and add a parent transform to the car transform manually

b. Instead of using V-Realm Builder, use the 3D World Editor, which is part of newer versions of Simulink 3D Animation product. It allows you to right click and cut and move around transforms in the tree view

c. Create a new VRML file and add the car as an INLINE node. This allows you to add an object defined in another VRML file as a single node.

MATLAB: How to load a .wrl file on to a GUI

set(gcf,'Units','pixels');
vrObjects.world = vrworld('spring.wrl');
open(vrObjects.world);
vrObjects.canvas = vr.canvas(vrObjects.world, gcf, [50 80 425 225]);
vrObjects.spring = vrnode(vrObjects.world,'spring');

Small example..

Best Answer

Related Solutions

MATLAB: How to group transforms in matlab’s Simulink 3D Animation v-realm builder

MATLAB: How to load a .wrl file on to a GUI

Related Question