IR-Ranger Board
GP2D02 based
| Author: | Sébastien Lelong, The SirBot Project, 2006 |
|---|
| Revision: 409 | Initial creation |
| $Revision: 441 $ | Convert into REST |
- Abtract
The IR-Ranger Board, connected to the Main Boad, provides a way of measuring distances, with the GP2D02 IR ranger.
Electronic diagram
The IR-Ranger board doesn't contain lots of components, as shown in the following diagram (only a diode):

Electronic assembly
The following pictures show the implementation of the components on a board:

Reverse side:

Calibration
The GP2D02 IR ranger output its distance measures as a byte. After enabling the ranger, the GP2D02 gives its result as a sequence of 8-bits:

The following chart shows how to convert this byte into a cm distance:

The distance accuracy depends on the reflective object material, and other stuffs... Let's say the distance is reliable between 10cm (byte with decimal value ~200) and 80cm (byte with decimal value ~75).
In order the robot to provide distances, we have to found the approx. formula of this chart. Taking points on the chart, putting the whole into Excel, gives the following chart:

Now we have the formula: f(x) = (760893/x)^(1/2.1286). The robot will be able to easily convert its received bytes into human readable distances...