Mechanical Principles Dynamics of Rotating Systems

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The discussion focuses on solving a mechanical dynamics problem involving a rotating system. Key calculations include determining the velocity of the piston (VBO), the angular velocity of link AB (ωAB), and the acceleration of point B relative to A (aBA) at an angle of θ = 45°. Additionally, it addresses finding the angle θ when the velocity of point B is zero and when the angular velocity of link AB is at its maximum, as well as calculating the maximum angular velocity of link AB. Participants suggest using vector definitions and resolving velocities into components to simplify the problem-solving process. The conversation emphasizes the importance of understanding the relationships between the components of the system.
mally baringon
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1. For the mechanism shown in FIGURE 1 determine for the angle
θ = 45°:

(i) the velocity of the piston relative to the fixed point O (VBO)
(ii) the angular velocity of AB about point A (i.e. ωAB)
(iii) the acceleration of point B relative to A (aBA).

(b) Determine the value of the angle θ (measured from vertical) when:
(i) the velocity of point B = 0
(ii) the angular velocity of link AB a maximum.

(c) What is the maximum angular velocity of link AB?
upload_2017-5-31_15-50-21.png

Homework Equations


Vao = Loa x ωoa

The Attempt at a Solution


Vao = Loa x ωoa = 0.005 x 10pi 0.1570

velocity triangle cosθ = Vbo/Vao

VBo =cos45 x Nao = 0.707 x 1.5708 = 1.1107 m/s^-1


I just have no idea where to start or what numbers to use where
 

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Try to define de displacement of point B as a function of de alngle theta. You can define vectors from origin O to help you.
 
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Diegor said:
Try to define de displacement of point B as a function of de alngle theta. You can define vectors from origin O to help you.
That would certainly work, but is unnecessarily complicated for the specific questions asked.
@mally baringon, if you resolve the instantaneous velocities of A and B into components along the rod and normal to the rod, what relationship must exist between them?
 
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