That's a pretty cool car and the author is correct about it being fast. I didn't see the article or BOM posted on the website. I'll be interested to see the circuit schematic diagram and Arduino sketch. Love to share it with my ITT Tech Microprocessor and Microcontroller students.
the next step is obviously for the vehicle to run based on a stored sequence of moves, followede by running moves dictated by sensor inputs. It could race against other vehicles on an oval track without needing to be super adaptive, so that would be a good choice of a starting point.