During flight, the operational wing sweep angle can be varied from 28 to 68 degrees relative to the pitch axis of the aircraft. This is a relatively simple planar mechanism of three links (ground, actuator, and wing), but uses linear actuation rather than direct rotation to control the sweep of each wing. A diagram with showing the overall dimensions of the aircraft and the mechanism architecture are shown below.
F-14 Aircraft Dimensions
F-14 Wing Sweep Mechanism
The mechanism is designed to provide significant mechanical advantage over the full range of motion and driven by an actuator similar to that shown below, which uses a gear train and lead screw to convert rotational motor input into linear actuation.
Linear Actuator Section View
A simple animated Solidworks model of the mechanism is shown to the right (note: model is not to scale).
The following kinematic analysis is based on wing sweep system performance shown in simulations and performance characteristics of industrial long-throw linear actuators which could be used to drive the mechanism. The time required for full mechanism actuation was assumed to be 60 seconds, and . This is consistent with the range of motor speeds on suitable lead screw style linear actuators is . The motor speeds on these actuator typically range from approximately 4000-9000 rpm. The motor speed curve shown below was derived using these values.
Input Motor Speed Curve
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Solidworks Mechanism Animation (not to scale)