RF wireless PWM DC motor speed control

The transmitter circuit below consists of WZ-X01 RF module, Holtek HT-640 encoder and 8 bit A/D converter. U1 ADC0804 converts the analog voltage to digital data, U2 encodes that data (D0~D6) along with D6, D7 and transmitting through the RF transmitter module.

The potentiometer VR1 varies the voltage to the A/D U1 pin6, since only the lower 6 bits are used; the trim pot VR2 has to adjust so that the maximum input to the U1 will not exceed 1.25V. The S2 (D6) and S3 (D7) are used for controlling the rotation direction of the motors. S1 set the transmitter address; this address has to match with the address of the decoder circuit

.Source: WZMICRO

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Applying Wireless Sensor Network for the Blind U-bus System

This paper proposed the U-bus system design based on wireless sensor network (WSN) for blind people. This system has two main parts. First part is blind people recognition. Another part is communication between a bus and bus station.

Blind people recognition part is constructed simple device and system. This part decides existing or non-existing of the blind at bus station. And then if pre-process recognize blind people, the bus station will communicate the bus.

We make up the announcement system about arrived bus information for the blind people using these parts. This announcement about arrived bus is very useful to blind people for taking the bus.

Download Wireless Sensor Network apply for the Blind U-bus System.pdf