This video is part of a series of videos presenting solutions of problems related to the machine dynamics topic.
This video presents the solution of problem dealing with the application of Grashof law.
In this problem we are asked to determine if
The mechanism shown here is a Grashof or non-Grashof mechanism
And if the this mechanism is double-crank, double-rocker, or crank-rocker mechanism.
Here the effective lengths are the ones connecting the pin joints.
So we should consider the distances A B, B D, D F, and A F.
The distances A C, B C, D E and E F, does not affect the behavior of this four-bar mechanism.
Here the shortest link is A B having a length of 22 cm.
The longest link is A F having a length of 29 cm.
The two other links B D and D F are 27 cm and 26 cm long, respectively.
Thus, the shortest link and longest link, together, make 51 cm.
And the sum of the length of the two other links is 53 cm.
Here, the sum of lengths of the shortest and longest links is lower than the sum of lengths of the two other links.
Therefore, the four-bar mechanism shown here is a Grashof mechanism
As the mechanism here is Grashof, and as the shortest link, A B C, is connected to the ground, then the mechanism is crank-rocker.
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