It has been easy to modify the original B-robot EVO adding new Off-road wheels (regular 83 mm diameter RC buggy wheels, quite easy to get and inexpensive). If you already have a B-robot, just modified the parameters indicated below in its code or upload this slightly modified CODE version to the Arduino: BROBOT OFFROAD
B-ROBOT is a remotely controlled self-balancing arduino robot created with 3D printed parts. With only two wheels, B-ROBOT is able to maintain its balance all the time by using his internal sensors and driving the motors. You can control your Robot, making him move or spin, by sending commands via a Smartphone, Tablet or PC while it maintains its balance.