Relates velocities and accelerations of points on a rotating body.
For plane motion, the velocity of point B is v_B=v_A+ω×r_B/A, and acceleration includes tangential αr and centripetal ω²r terms. Used for linkages, wheels and robot arms.
A crank of 0.1 m at 100 rad/s has pin speed 10 m/s.
Rigid bodies rotate and translate together, so relating point velocities and accelerations is needed for linkages, wheels and rotating parts.
Relates velocities and accelerations of points on a rotating body.
Rigid bodies rotate and translate together, so relating point velocities and accelerations is needed for linkages, wheels and rotating parts.
The velocity of one point equals the velocity of the other plus the angular velocity crossed with the position vector between them.
The rotation axis and the position vectors have directions, so vector cross products describe the motion in three dimensions correctly.
Typical applications include finding the speed of the tip of a crank arm, computing the velocity of a point on a rolling wheel and analysing the motion of a link in a crank-slider mechanism.
Study "Coefficient of restitution" first (topic 33 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
Rotation plus translation. Relative velocity method. Instantaneous centre alternative.
A crank of 0.1 m at 100 rad/s has pin speed 10 m/s.
The next topic is "Instantaneous centre of rotation", which builds directly on this one.
It is classed as Beginner in Engineering Mechanics (topic 34 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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