Calculation Model Error

The model we used to calculate the constraints on our machine can be found here. Since there are so many variables that can be modified according to changes in our design, we varied some while keeping others constant as physical restrictions. One of these constants was mass, which is listed as 5kg (approximately 11 pounds) according to the attached model. The calculations of required motor torque, acceleration, and maximum velocity depend on this value. After actually creating our robot, however, the total mass was measured to be around 8 pounds. This significantly reduces the validity of our calculations. Because we neglected to consider a range of possible masses instead of one sample mass we significantly overestimated the previously mentioned key parameters of our system. As a result (and as stated in our last post) we are unable to push the tower as originally planned. The frictional force on the wheels accounting for the propulsion of the vehicle is not high enough to overcome the frictional force acting on the tower. A slipping of the wheels occurs because of this fact, disabling this part of the robot's functionality.