We want to introduce you to a very special device now: the differential gear.You probably know that there's at least one differential gear in every car. What you might not know is why the differential gear is so important.
Let's do an experiment together. Take two wheels from your NXT kit and connect their hubs with the longest axle.
 

 
Now put the wheels on your table and push them gently" They run smoothly and advance some feet, going straight. Very straight. Keep the axle in the middle with y...
Continue reading ...