SmartElex RLS-08 Analog & Digital Line Sensor Array

With its eight IR LED/phototransistor pairs, the SmartElex RLS-08 Analog & Digital Line Sensor Array is an excellent detector for a line-following robot. Every sensor has a potentiometer to change the sensitivity of the individual sensors in addition to its own digital and analog output.

Though it can be used as a general-purpose proximity or reflectance sensor, the TCRT5000 reflectance sensors array is designed to be a line sensor. Eight pairs of IR emitters and receivers (photoresistor/photodiodes) evenly spaced at intervals are carried by the module, which is a convenient carrier.

Each phototransistor equips a pull-up resistor to form a voltage divider that produces an analog voltage output between 0 V and VIN (which is typically 5 V) as a function of the reflected IR. The lower output voltage is an indication of greater reflection.

The outputs are all independent, but the LEDs are arranged in pairs to halve current consumption. The LEDs are controlled by a MOSFET with a gate normally pulled high, allowing the LEDs to be turned off by setting the MOSFET gate to a low voltage. Turning the LEDs off might be advantageous for limiting power consumption when the sensors are not in use or for varying the effective brightness of the LEDs through PWM control.

The LED current-limiting resistors for 5 V operation are arranged in two stages; this allows a simple bypass of one stage to enable operation at 3.3 V. The LED current is approximately 20-25 mA, making the total board consumption just under 100 mA.

Features:

1. Potentiometer to adjust the sensitivity of the individual sensors.
2. The module is a convenient carrier for eight IR emitter and receiver pairs evenly paced.
3. Distance between each IR Sensor: 15mm
4. Uses 8 sensors for best resolution
5. Great useful in building fast line following and grid navigating robots
6. Comes with easy to use digital outputs with a direct connection to microcontrollers
7. The array has mounting holes of 3mm diameter for easy mounting

Package Includes:

1 x SmartElex RLS-08 Analog & Digital Line Sensor Array