A base has wheels, including a drive wheel, for wheeling the base over a floor. A handle, including a handgrip, is connected to the base for propelling the base by manually applying a force to the handgrip. A motor has an output shaft coupled to the drive wheel. A controller has different operative modes. They include a driving mode in which the controller powers the motor to rotate the drive wheel in a direction corresponding to a direction of the force applied to the handle, and a non-driving mode in which the controller refrains from powering the motor to rotate the drive wheel while a user grasps and applies force to the handgrip to propel the base.