RF modules are widely used in electronic design owing to the difficulty of designing radio circuitry. Good electronic radio design is notoriously complex because of the sensitivity of radio circuits and the accuracy of components and layouts required to achieve operation on a specific frequency.

The Obstacle Detector sensor module is perfectly adaptable to the environment light, IR Object Avoidance Sensor has a pair of infrared transmitting and receiving tubes; transmitting tube emits infrared in a certain frequency, when detecting direction meets with obstacles(reflecting surface), reflected infrared will be received by the receiving tube; after the comparator circuit processing, the green indicator will light up, at the same time signal output interface to output digital signal(1 low-level signal). Users can adjust the detection distance through the potentiometer knob, effective distance range 2~30cm and working voltage is 3.3V to 5V. The Obstacle Avoidance module LM393 can be widely used in robot obstacle avoidance, obstacle avoidance car, line count, black and white line tracking, and so on many occasions.

HC SR04 HC-SR04 Ultrasonic Sensor also called HC-SR04 Ultrasonic Range Finder. Ultrasonic Sensor module HC-SR04 provides 2cm – 400cm non-contact measurement function, the ranging accuracy can reach to 3mm. The modules include ultrasonic transmitters, receiver and control circuit.