Black is white

For Lava Palava challenge,  We got a bunch of black chart sheets and painted a white strip (1.9cm) in the middle to try out 'line following'.

But the sensors on our bot just couldn't tell the difference between black and white. We got really worried that the sensors don't work. We tried adjusting the sensors sensitivity but with no luck.

We then had this AHA moment that our black sheet may not be black enough for the sensors. And it indeed was the case. 

Workaround... black cello tape to our rescue.

Lava palava challenge, here we come!!