Whippletree (mechanism)

Several whippletrees may be used in series to distribute the force further, such as to simulate pressure over an area as when applying loading to test airplane wings.

Thus, with two animals, each has its own whippletree, and a further one balances the loads from their two whippletrees—an arrangement sometimes known as a double-tree, or for the leaders in a larger team, leader-bars.

Whippletrees are also used in modern agriculture—for example, to link several ganged agricultural implements such as harrows, mowers or rollers to a tractor.

Linkage-type mechanical analog computers use whippletree linkages to add and subtract quantities represented by straight-line motions.

[6] The illustration here of whippletrees for a three-animal team is very similar to a group of linkage adders and subtracters: "load" is the equivalent of the output sum/difference of the individual inputs.

Inside the computer, cylinders on the knob shafts have thin metal tapes wrapped around them to convert rotary to linear motion.