Hate that your robot runs into everything? This will fix that problem. With 8 sonic sensors this looks complicated…but in fact I made this very easy. I try to post projects that help you learn about Arduino and show an ‘outside the box’ concept. This post will help you understand 595 switching, pro-minis as a programmable sensor, and the grand use of real time led feedback. If you enjoy Arduino as a ‘copy and paste and plug-in’ you might just skip this.
I like to use pro-minis. They are about $2.50, work as a full blown uno, and installing headers makes them very flexible. Used as a sensor micro you can have it ‘do what you want’ instead of what a purchased sensor dictates. With I2C using only 2 wires they can be tied together all on one line. So move over MEGA I can have 4 minis running 4 separate lines of code all at the same time, at just $10.00. Here I use a mini to pop the sonic sensors through a 595 and show realtime led distance. Then just share 8bits of data with the mother board. This takes the load off the mother board and makes the her code very simple.
There is a problem with sonic sensors…no visual feedback. You never know if the sensor is just a dead weight or working! I believe who ever came up with ‘BLINK’ is smarter than Einstine. Just ONE led and a world of information is relayed by the blinking. So a sonic sensor needs realtime feedback. Here I used an array of leds to monitor each sensor. You don’t need them, just make the sensors without the leds. But to have the leds on the PCB is helpful.”