Lecture - 4 (Kinematic chain, mechanism & machines)

KINEMATIC CHAIN

If all the links are connected in such a way such that the first link is connected to the last link in order to have close chain and if all the relative motion in this close chain are constrained than such a chain is known as kinematic chain
In below figure there is an example of kinematic chain

MECHANISM
If any one link of kinematic chain will be fixed than we get a mechanism. In below figure there are 2 kinematic chain which are used as mechanism


Always remember only kinematic chain will form a mechanism because kinematic chain has constrained motion. If any of chain having unconstrained motion then it will not form a mechanism. In below figure a constrained chain is forming a mechanism not unconstrained chain.


MACHINES

Combination of different mechanisms through which our desired output is obtained are known as machines.
Examples are- 





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