User Manual

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convert the voltage into digital values by the A/D converter on the MCU. And we can tell the light
intensity then by this value.
The module can be used to sense the ambient luminance. The blue potentiometer is to adjust the
sensitivity – you can change it to adapt to specific circumstances. There are two mounting holes
of 3mm diameter on the module for easy assembly on your robot.
Ultrasonic Obstacle Avoidance Module
This module contains an ultrasonic sensor to detect the distance to an obstacle in front. It is usually
used on robots to avoid obstacles. With the two holes, it can be assembled easily on the robot.
There is power indicator light added onside to indicate power on/off. The 3-pin design makes it
unique among most of the ultrasonic module in the market: the same pin to trigger and receive
signals. The 3-pin anti-reverse cable included makes the wiring tighter and more convenient. Also
the beautiful cartoon design and the red PCB add to its fascination.
The 25kHz ultrasonic module differs from common 40kHz ones. It is not so precise in distance
measurement, but it has a wider detecting range of about 30 degrees. Thus it can detect the
obstacle near ahead, and measure the distance if it’s assembled on the PiCar. Though a 40kHz
ultrasonic measures distance precisely, it can only detect obstacles which is right in front. Therefore,
the 25kHz ultrasonic module is more preferably applicable to an obstacle avoidance car, or
projects require a large detection range instead of accurate distance measurement.
SunFounder SF006C Servo