A force is always applied to a moving object (movable body). The force applied to this movable body is the basic knowledge required for engineers to design mechanical devices. The law of inertia in particular is an important concept in designing high-speed drive mechanisms.

(1)Law of motion

1)Newton's first law --- sometimes referred to as the law of inertia

- Objects will remain in their state of motion unless an outside force acts to change the motion.

- A moving object (movable body) stays in motion at a constant velocity and an object at rest remains in the resting state, unless acted upon by an external force.

- This type of motion is called inertia and this law is often referred to as the law of inertia.

- For linear motion mechanism, it is necessary to design a control unit that applies a force to the opposite direction after reducing acceleration to zero at the termination point where the direction of reciprocating motion changes.

- This acceleration change requires an external force. At this time, the force of inertia acts near the termination point of reciprocating motion.

- Therefore, it is necessary to design a support structure strong enough to withstand the force of inertia.

- The following figure is an explanatory diagram of how the forces are applied to the ball screw driving mechanism.