Mobile robotic vehicle

A robot comprising:

• a robot chassis having a forward end, a rearward end and a center of gravity;
• a support surface moveably connected to the chassis and configured to propel the robot chassis;
• a trailing arm rotatable about an axis located rearward of the center of gravity of the robot chassis;
• and
• a controller configured to execute a stair climbing control routine stored on the mobile robot, including causing the robot to perform operations comprising:
• driving the support surface over an underlying surface towards a stair;
• pivoting the trailing arm downward against the underlying surface and causing the forward end of the robot chassis to raise up off the underlying surface, the trailing arm having a distal end that contacts the underlying surface forward of the center of gravity of the vehicle;
• further driving the support surface to cause the forward end of the vehicle to ascend a riser of the stair, the support surface generating sufficient traction against the riser to climb the riser as the support surface is driven;
• and
• pivoting the trailing arm so that the distal end contacts the underlying surface at a point behind the support surface while the robot ascends the stair.