*See picture below for a more detailed explanation of the system
| Positives | Negatives |
| The concept was simple (spin the rod to move a nut which moves the car) | threaded rod would start vibrating like a string because of any slight misalignment or bend in the rod. This would mean that much more torque was required from the motor at certain times during a rotation. It was unstable. |
| Gear reduction was not needed, as the car (attached to the nut) would move a very short distance (the pitch of the threads) for each rotation. | threaded rod would start vibrating like a string because of any slight misalignment or bend in the rod. This would mean that much more torque was required from the motor at certain times during a rotation. It was unstable. |
Method was not chosen
In this setup, the motor is attached to a threaded rod at its end, and the motor shaft is aligned exactly with the axis of the threaded rod. The other end of the rod is supported but spins freely in a hole. A nut is threaded onto the rod, and this nut is attached to the car. In this manner, as the motor shaft rotates, the nut and car will move linearly.