In this volume, we will learn about basic knowledge of motion in order to understand the motion state of a movable body.

(1) Fundamentals of motion

- "Motion" means that an object changes its position with respect to time.

- "Displacement" refers to positional changes of an object. (Since it quantifies the distance and direction, composition and resolution are also possible.)

- "Velocity" refers to the degree of displacement with respect to time. (Since it quantifies the distance and direction, composition and resolution are also possible.)   Unit = m/s

- "Uniform motion" means that an object travels at a constant velocity. It can be expressed as V (velocity) = S (travel distance) / t (time).

- "Acceleration" refers to a rate of velocity change with respect to time. A (acceleration) = {V - V0 (initial velocity)} / t
Unit = m/s²

- "Uniformly accelerated motion" refers to motion with constant acceleration.
The velocity after t seconds will be V = V0 + A・t
The travel distance after t seconds will be S = V0・t + (1/2) A・t²

Velocity and travel distance are used for estimating work tact (time) or life hours relative to the sliding distance when designing a linear motion mechanism. They are also utilized for assessing the moment of inertia force.

(2) Motion expressions

The following figure shows a relationship between the time and speed of uniform motion. It is a typical pattern of linear motion (linear reciprocating motion).