Month: February 2016

I2C Hub with integrated level shifter

Today I finished my self designed I²C Hub with an integrated level shifter. As level shifter I used the “4-channel I2C-safe Bi-directional Logic Level Converter – BSS138” from adafruit. Now it is possible to connect to the hub four 3.3V I²C devices and five 5.0V I²C devices and the Raspberry Pi as master. For the first text I connectec two ultrasonic sensors SRF08 as shown in the picture below. The picture below shows the I²Cdetect command executed in the terminal window. Both connected SRF08 ultrasonic sensors where found on the bus. The hub is perfect for my robot car...

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Raspberry Pi – controlling servo motors

This post is about controlling two servo motors with a Raspberry Pi. You can buy cheap pan & tilt kits or build one by yourself. I bought a pan & tilt kit for my robot-cars and build one kit by myself with two servo motors and a cardboard tube. To build the security-robot I used additional components like a Raspberry Pi 3, step-down converter, IR sensors and a level shifter plus wires. The list below shows all the electronic components I used to build my security-robot. But this post is not about the robot itself this post is about...

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SRF08 Ultrasonic Range sensor with I2C bus

I decided to buy the SRF08 ultrasonic range finder sensor because of the I2C bus. I build too many sensors into my robot car and got problems with all the wires installed inside the car. The HC-SR04 sensors I used before measured many failures because of all the magnetic fields generated by the 60 wires I used to connect everything. With a bus like the I2C bus used to communicate with the sensors the problems with the electromagnetic interference where solved. The sensors are the price of 39,- € worth. You do not get only an ultrasonic sensor. In the...

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