Assemblies of rigid links that transform motion, such as four-bar linkages.
A mechanism is a chain of rigid links with joints to transform motion: four-bar, slider-crank, quick-return. Grashof condition (s+l ≤ p+q) says whether a link can fully rotate. Kinematic synthesis designs links for a desired motion.
Windscreen wipers use a four-bar linkage.
Linkages convert motion between forms, such as rotation to reciprocation, and they are the basis of engines, presses and robot joints.
Assemblies of rigid links that transform motion, such as four-bar linkages.
Linkages convert motion between forms, such as rotation to reciprocation, and they are the basis of engines, presses and robot joints.
A mechanism of four rigid links connected by four revolute joints. Its motion depends on the link lengths, and it can be a crank-rocker, double-crank or double-rocker.
Use a position analysis with loop closure equations, or simulate the linkage in CAD software to check range and clearance.
Typical applications include designing a crank-slider for a piston pump, converting a motor's rotation into the motion of a press ram and planning the joint movement of a robotic arm with four bars.
Study "Critical speed of shafts" first (topic 82 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
Grashof crank-rocker. Transmission angle. Piston engines use slider-crank.
Windscreen wipers use a four-bar linkage.
The next topic is "Degrees of freedom", which builds directly on this one.
It is classed as Advanced in Engineering Mechanics (topic 83 of 106). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Engineering Mechanics.
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