Hexapod.

This model describes a hexapod, a 6 legged mechanism. Another name of a hexapod is a Stewart platform. This type of mechanisms is used when a load should both translate and rotate in all directions (6 degrees of freedom). Typical applications are flight simulators, where the movement of a real plane cabin should represent the movement of the simulated plane. Another application area is in micromanipulation (precision engineering).

The hexapod structure is modelled in the 3D Mechanics Toolbox. The position of the 6 legs is measured and each leg is actuated in the longitudinal direction. A PID controller on each leg steers the actuation force with respect to some extension error. Inverse kinematics calculates the reference extension of each leg from the desired plate references. In the animation there are two frames visible, one that represents the desired reference position, and one that represents the actual plate position.

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