Engscope

Engscope is home of the Jegway, a Segway like device made from Legos! Actually, I am by no means the first to make this out of Legos Mindstorm NXT set. That credit would go to Steve Hassenplug’s Legway, the world-famous self-balancing LEGO robot. The Legway uses an optical detector to maintain a certain distance from the sensor to the ground. Next, there’s the NXTway, by Philo. It uses the optical sensor that comes with the NXT set. Lastly, the inspiration for the Jegway comes from the NXTway-G by Ryo Watanabe. His implementation involves a gyroscope and displays outstanding stability.

Of course, I can just leave it at that. A real Segway uses accelerometers and gyroscopes. The reason for the use of both types of sensors comes down to the estimation of tilt angle, and I will discuss more on the subject in each of the Jegway segments.

I have made two implementation, using just the gyroscope, similar to Ryo Watanabe’s NXTway-G, and another that combines a gyroscope and accelerometer to get a more accurate measure of the tilt angle. This idea comes from both the original Segway, and also Trevor Blackwell’s balancing scooter.

Jegway Rev0 – Implemented using the Hitechnic gyroscope.

Jegway Rev2 – Implemented using the Hitechnic gyroscope, Hitechnic accelerometer and the Mindsensor PS2 controller.

Enjoy, you’ll find documentation as well as code for both versions. The code is implemented in RobotC. Originally it was written in NXC, but because NXC does not support floating point arithmetic, I eventually broke from the pope and converted to RobotC.