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Abbe error, named after
Ernst Abbe Ernst Karl Abbe (23 January 1840 – 14 January 1905) was a German businessman, optical engineer, physicist, and social reformer. Together with Otto Schott and Carl Zeiss, he developed numerous optical instruments. He was also a co-owner of Ca ...
, also called sine error, describes the magnification of angular error over distance. For example, when one measures a point that is 1 meter away at 90 degrees, an angular error of 1 degree corresponds to a positional error of over 1.745 cm, equivalent to a distance-measurement error of 1.745%. In machine design, some components are particularly sensitive to angular errors. For example, slight deviations from parallelism of the spindle axis of a
lathe A lathe () is a machine tool that rotates a workpiece about an axis of rotation to perform various operations such as cutting, sanding, knurling, drilling, deformation, facing, threading and turning, with tools that are applied to the w ...
to the tool motion along the bed of the machine can lead to relatively large (undesired) taper along the part (i.e. a non-cylindrical part). Vernier calipers are not free from Abbe error, while screw gauges are free from Abbe error. Abbe error is the product of the Abbe offset and the sine of angular error in the system. Abbe error can be detrimental to
dead reckoning In navigation, dead reckoning is the process of calculating the current position of a moving object by using a previously determined position, or fix, and incorporating estimates of speed, heading (or direction or course), and elapsed time. T ...
. Formula: : \epsilon = h \sin \theta \epsilon is the error. h is the distance, sometimes called the ''Abbe offset''. \theta is the angle.


References

{{reflist Error Trigonometry de:Kippfehler