# Revision history [back]

The wheels aren't attached to the box on your urdf because this formula is wrong :

y_reflect*(base_width/6+wheel_ygap) = +/- 0.12398333333


The correct way to calculate y_wheel is :

y_wheel =  y_reflect * (base_length/2 + wheel_width/2) = +/- 0.0862


Which is almost equal to your wheel_ygap (0.088) which is the same value for the link you've defined in the sdf file :

<pose>0.1 0.088 0.05 0 1.5707 1.5707</pose>