3. Applied kinematics

3.1 Machine in the general sense

The purpose of applied kinematics is to deal more specifically with the general mechanisms that go to make up a machine.

According to Ampère (Essai sur la philosophie des sciences, 1830), a machine is an instrument that can be used to change the direction and speed of a movement. Mechanisms appear as elementary machines. Reuleaux (Cinématique, 1877) is more precise: a machine is an assembly of resistant bodies, arranged in such a way as to force natural mechanical forces to act, giving rise to determined movements.

In this paragraph, we propose to give the general methods common to all mechanisms, i.e. to look for cause-and-effect relationships in machine phenomena. These cause-and-effect relationships...