How to make an obstacle avoiding robot. via instructables

Step 1: Components
I used my previous project’s shield and ultrasound sensor in this project.

Learn how to make the Radar from HERE! The build is explained there.

The base for the whole build is an old HDD lid. It is light weight and it hold’s its shape well.

The wheels are just from an old toy car.

Two servos for the wheels is needed and one servo for the radar.

And of course some kind of Arduino based board is needed. I used Intel Edison+ Arduino breakout board.

Step 2: Making a forever rotating servo

Forever rotating servo means that it will turn more than the basic 0-180 degrees.

The forever rotating servo is great for this type usage. You can change the speed by entering differed value to the servo and also you can change the direction of rotation.

First find a simple test code from the internet to set up your servo.

I used a basic potentiometer on a shield and set the servo to 90 degrees. This way it is in the middle of its original rotation and it is easiest to program. Also the rotation speed of the servo is the same in both 0 and 180 degree.

Then remove the cap from the servo and pull out the gears.

In one gear there should be a small pin that stops the servo if it is turning too much. Cut that off.

Then make absolutely sure that the potentiometer is at 90 degree position and drop a small drop of superglue on the potentiometer to jam it on its place.

Then just put all the gears back and test the workings of the servo.

Full tutorial