Crank Rocker Mechanism

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As crank-rocker mechanisms pivot between two sharply defined angular limits, one can consider that it's in this setting that the crank operates as an input device while the rocker takes on the role of a key output. It becomes evident then, the exact angles where movement is at its minimum and rocker is placed squarely at each of its end points constitute what's referred to as dead-center positions within this mechanical context known colloquially as a four-bar configuration.