Kinematics is the branch of science that deals with motion without regard to the forces that cause movement. On the other hand, kinetics is the branch of science that also takes on the forces that cause motion, as well as the weight and effects of inertia in the study.
Kinematic link and kinematic pair
• Link: It is defined as a machine element with relative movement with respect to other parts of the machine element.
• The kinematic pair is defined as a two-link joint that allows relative movement between elements or links. The kinematic torque is formed when there is mechanical contact between them and has mechanism arrangement.
• The lower pair is said to be formed when two elements have surface contact between them.
• A higher pair is said to be formed when two elements have point contact between them.
Kinematic chain
The kinematic chain is one in which the number of links is so connected that the relative movement of any point of a link with respect to any other point in the other link follows a law that governs
• L = 2/3 (J + 2) Where, L = Number of links, J = Number of joints
or
• J = 3/2 (L) -2, where, H = Number of Upper Pairs
• A higher pair = two lower pairs.
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