Double Cardan Joint

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A double cardan joint, comprised of two universal joints mounted back to back with a central yoke, replaces the intermediate shaft. If the angles between the components are equal, the second cardan joint cancels out errors from the first and functions as a constant velocity joint. In practice, centering balls may not maintain exact angles, causing slight speed fluctuations at high articulation angles. Double cardan joints are commonly used in steering columns, eliminating the need to phase universal joints correctly, and in rugged vehicles for their ability to handle high articulation angles and impulsive torque loads. Note that dimensions are approximate; animations of higher quality can be found at the provided link.