Self-balancing and power-assisted payload carrying vehicles using operator-applied force sensing

A method of operating a hand truck carrying a payload over a surface, the hand truck having first and second laterally disposed wheels positioned along a central axis, the method comprising:

• a user setting the hand truck in an orientation at a static balance point by positioning the hand truck to place a center of mass of the hand truck and the payload directly above the central axis such that only the first and second laterally disposed wheels are contacting the surface;
• and
• subsequent to the user setting the hand truck in the static balance point orientation:
• measuring a force, applied by the user to the hand truck, that moves the hand truck to another orientation away from the static balance point orientation, the measured force comprising a direction and a magnitude;
• and
• providing torque via one or more motors to each of the first and second laterally disposed wheels to cause each of the first and second laterally disposed wheels to rotate in a respective direction as a function of the measured force direction in order to place the hand truck back at the static balance point orientation and such that the magnitude of the measured force applied by the user is reduced to at or below a predetermined threshold value.