=Introduction= The three-point hitch is a widely used type of hitch for attaching ploughs and other implements to an agricultural or industrial tractor. The three points resemble either a triangle, or the letter A. Three-point attachment is the simplest and the only statically determinate way of joining two bodies in engineering.
=Challenges=
Size categories
There are five different hitch sizes, called categories. The higher category hitches have sturdier lift arms and larger connector pins.
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There are also variants to the above categories denoted by N, (narrow). These utilize the pin sizes of the listed category, but the width of a category one step lower. The N variations are common in “quick hitches” and allow larger tractors to easily hook onto smaller utility implements.
:* refers to implement end; tractor end not specified
=Approaches= <gallery> File:Plate-three-point-hitch.scad.png|Three point hitch plate adapts to 5/8 inch, 3/4 inch, 7/8 inch </gallery>
=References= * [https://en.wikipedia.org/wiki/Three-point_hitch Wikipedia: Three-point hitch]