ACTIVITIES

Code for Testing Photodiode Sensors
Test Photodiodes
Photodiode and Variation in Lighting
Directional Changes
Calibrating for Botball

Follow the Light! COMING SOON

IC Sensor Test (Grant, NASA Ames) COMING SOON

CYBER LAB SENSOR PAGES

 Infrared

 Range

 Touch

 Encoder

Photodiodes are analog sensors that return a low numerical value when exposed to a light source and a higher numerical value when less light strikes them. These sensors are quite sensitive to light, and have a wide field of view. To derive any directional information out of them, they must be shielded. Black electric tape and aluminum-foil are good materials for constructing a light shade. Roll these materials into small tubes and slide them over the sensor eyes. Be sure to cover the back of the sensor as well. By using two or three of these sensors you can easily have your robot orient itself with respect to a point of light. Photodiodes should only be used in analog ports 2-6 on the HandyBoard.

 

 

 

 

Figure 1. Photodiode sensor modified for the HandyBoard

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 How a Photodiode Works

A photodiode receives light. The photodiode will pick up a signal carried by a modulated light beam and produce a modulated current (MIT). The photodiode captures variations of light intensity and displays the readings to your HandyBoard's