Name: slider-crank motion and point b acceleration
Uploaded: 2024-03-07T13:22:24.000Z
Duration: 1 min 10 s
Channel: JoVE

In a slider-crank mechanism, the motion is not uniform due to the varying angle between the crank and the connecting rod.
The motion of segment AB can be studied by attaching a fixed reference system at point O and an additional translating frame of reference at point A.
The absolute linear velocity of point B is expressed as the vector sum of the absolute linear velocity of point A and the relative velocity of point B with respect to point A.
Taking the time derivatives gives the absolute acceleration of point B, which is the vector sum of the absolute acceleration of point A and the relative acceleration of point B with respect to point A.
The motion of point B with respect to point A is a circular path, so the relative acceleration of point B is expressed as normal and tangential components.
The motion of point B is then the result of the linear acceleration of point A, the angular acceleration, and the angular velocity of point B with respect to point A.

relative motion analysis - acceleration

Relative Motion Analysis - Acceleration

A slider-crank mechanism converts rotational motion from the crank into linear motion of the slider or vice versa. This mechanism consists of three main parts: the crank, the connecting rod, and the slider. The movement of the slider-crank is an example of general plane motion as the fluctuating angle between the crank and the connecting rod. Consider a segment AB where point A is at the end of the slider and point B is on the diametrically opposite end to point A, on a crack. The variance in motion of segment AB can be studied by assigning a stationary reference system at point O and an additional translating frame of reference at point A.
The absolute linear velocity at point B can be depicted as the sum of two vectors: the absolute linear velocity of point A and the relative velocity of point B when seen in relation to point A. When time derivatives are taken into account, the absolute acceleration of point B is obtained. This acceleration is effectively the vector sum of the absolute acceleration of point A and the relative acceleration of point B in relation to point A.
The path of point B&#39;s motion, when compared to point A, is circular. Consequently, the relative acceleration of point B is expressed in terms of its normal and tangential components. The movement of point B is a result of three factors - the linear acceleration of point A, the angular acceleration, and the angular acceleration of point B when compared to point A. Therefore, the motion in a slider-crank mechanism is a complex interplay of these factors, making it non-uniform.

In a slider-crank mechanism, the motion is not uniform due to the varying angle between the crank and the connecting rod.
The motion of segment AB can be ...

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slider-crank motion and point b acceleration

A slider-crank mechanism turns rotational motion from the crank into linear motion of the slider, and it can also work the other way around. It has three main parts: the crank, the connecting rod, and the slider. Because the angle between the crank and the connecting rod keeps changing, the motion is an example of general plane motion.

To study the motion, a stationary reference system is placed at point O, and a translating frame is added at point A. The segment AB is then analyzed, with point A at the end of the slider and point B at the opposite end on the crank. The absolute linear velocity of point B is the sum of the absolute linear velocity of point A and the relative velocity of point B with respect to point A.

When time derivatives are taken, the absolute acceleration of point B is found. It is the vector sum of the absolute acceleration of point A and the relative acceleration of point B with respect to point A. Since the path of point B relative to point A is circular, the relative acceleration has normal and tangential components.

The motion of point B depends on three factors. These are the linear acceleration of point A, the angular acceleration, and the angular acceleration of point B relative to point A. Together, these parts make the motion in a slider-crank mechanism non-uniform.

Slider-Crank Motion and Point B Acceleration

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A slider-crank mechanism turns rotational motion from the crank into linear motion of the slider, and it can also work the other way around. It has three main parts: the crank, the connecting rod, and the slider. Because the angle between the crank and the connecting rod keeps changing, the motion is an example of general plane motion. To study the motion, a stationary reference system is placed at point O, and a translating frame is added at point A. The segment AB is then analyzed, with...

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key terms and concepts

Explore how a slider-crank mechanism links rotational and linear motion, and how point B acceleration comes from absolute, relative, normal, and tangential parts.

Slider-Crank Motion and Point B Acceleration | JoVE K12

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Slider-Crank Motion and Point B Acceleration

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