Differences

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--- buzz_kh4 [2018/03/20 15:53] – [Sensors] root
+++ buzz_kh4 [2018/03/21 00:08] – root
@@ Line 33: / Line 33: @@
       * ''value'', which is the actual reading. Each individual sensor is saturated (value ''1.0'') by objects closer than 4 cm; the maximum range of the sensor is 12 cm. Between 4 and 12 cm, the readings follow an exponential law with the distance: ''%%4.14*exp(-33.0*distance)-.085%%''.
       * To activate this sensor in ARGoS, use the ''kheperaiv_proximity'' sensor.
+  * **Light sensors**
+    * The Khepera IV proximity sensor is a set of 8 infrared emitter/receiver pairs distributed regularly in a ring around the robot. The sensors are numbered 0 to 7. Sensor 0 looks straight ahead, and the numbers increase counterclockwise when looking at the robot from above.
+    * ''light'' is the Buzz table that contains the light readings. Each element of this table (e.g., ''light[0]'', ''light[1]'', ...) is in turn a table that contains two elements:
+      * ''angle'', which corresponds to the angle (expressed in radians) at which the sensor is located on the body of the robot
+      * ''value'', which is the actual reading. The sensors all return a value
+between 0 and 1, where 0 means nothing within range and 1 means the perceived
+light saturates the sensor. Values between 0 and 1 depend on the distance of the perceived light. In ARGoS, each reading ''R'' is calculated with ''%%R=(I/x)^2%%'', where ''x'' is the distance between a sensor and the light, and ''I'' is the reference intensity of the perceived light. The reference intensity corresponds to the minimum distance at which the light saturates a sensor.
+      * To activate this sensor in ARGoS, use the ''kheperaiv_light'' sensor.
   * **Battery sensor**