Stylus calibration and Prop registration

Virtual reality or augmented reality environments are not imaginable without tracked objects. These objects are the interface between the real and the virtual world. They are the heart of this application because they bring interaction to the scene. Normally, we deal with two forms of objects:

On the one hand, we have a stylus, the VR equivalent of a pen. A stylus is a very generic way to interact with the environment. It is, therefore, most often used, just like a mouse on a desktop. But a stylus is only useful when it is well calibrated, i.e., when the top of the stylus is defined as exactly as possible. In the first part of this work, we implemented a simple and universal method calibrating a stylus. The built solution is an Opentracker module, so we provide a really flexible opportunity for calibrating.

On the other hand, we have props, tracked physical things with a virtual counterpart. Here, it is also necessary to register these props exactly. Bad registration of props will produce inexact and unsatisfactory incoming results. A good working prop registration is the topic of the second part of this work. This solution is also an Opentracker module in combination with an OpenInventor program. So, it is possible to register physical props in an smart and easy way.

Stylus calibration

1) World coordinate system     2) Stylus
3) Top of the stylus and center of the hemisphere
4) Local coordinate system of the stylus     5) Searched vector
6) Hemisphere     7) Previous path of the back end



Prop registration

1) World coordinate system     2) Virtual prop
3) Physical prop     4) Local coordinate system of the physical prop
5) Stylus     6) Local coordinate system of the stylus
7) Searched rotation and translation



For more information please refer to the Bachelor's Thesis