Here i'm going to instruct you about making an Obstacle Avoiding Robot based on Arduino. I hope to do step by step guide on making this robot in very easy way. An obstacle avoiding robot is a fully autonomous robot which can be able to avoid any obstacle which it face when it move. Simply, when it met an obstacle while it moving forward, automatically stop moving forward and makes a step back. Then it looks it's two sides left & right and starts to move the best possible way; which means either in left direction if there is another obstacle in right or in right direction if there is another obstacle in left side. The obstacle avoiding robot is very helpful and it is the base of many large projects such as Automatic cars, robots used in Manufacturing factories, even in robots used in spacecrafts.
Solder two wires to each DC motor. Then fix two motors to the chassis using the screws. If you need any clarification, please watch this youtube video https://www.google.lk/url?sa=t&rct=j&q=&esrc=s&sou... and it will show you how to assemble the Smart 2WD Robot car chassis. Finally attach the Universal wheel (or ball caster wheel)