## 4. Reference frames

> 4.1 Introduction

> 4.2 Rigid frame

> 4.3 Moved frame

> 4.4 Relative measurements

## 4.1 Introduction

> This software enables us to operate with 3D reference frames. Every frame may have a parent frame. The number of parents of every frame should not exceed one. Position, orientation, linear and angular veloctity of every frame are relative to its parent frame. If a frame have no a parent then its parameters are relative to the single dedicated frame that we shall call zero frame. A link of frame to its parent corresponds to the button.

## 4.2 Rigid frame

Rigid frame corresponds to the button. Its property editor is shown below:

This editor enables us to edit fixed coordinates and transformation matrix.

## 4.3 Moved frame

The moved frame corrsponds to the button. Its property editor is shown below:

This editor enables us to link data-in to 7 motion parameters. First three define x(t), y(t), z(t) . Latest four formulas defines angular evolution (we use components of orientation quaternion). This component implements the Data consumer interface. So it should be linked by arrow(s) to its information provider(s).

## 4.4 Relative measurements

We may obtain parameters of motion of one frame relative to another. To do this use the component. It should be linked to the two frames as it is shown below

In this picture we have two frames: Frame and Base frame. The Measurements object provides information about motion parameters of Frame relatively to Base frame. The Measurements object is also a provider of information. Every information consumer may be linked by an to the Measurements object.