平衡环架（英语：Gimbal）为一具有枢纽的设备，使得一物体能以单一轴旋转。由彼此垂直的枢纽轴所组成的一组三只平衡环架，则可使架在最内的环架的物体维持旋转轴不变，而应用在船上的陀螺仪、罗盘、饮料杯架等用途上，而不受船体因波浪上下震动、船身转向的影响。

用在固定罗盘的平衡环架用常称为卡尔丹诺式悬吊（Cardan suspension），以意大利数学家暨物理学家杰洛拉莫·卡尔丹诺（1501–1576）为名，因为他对平衡环架作出详细的描述。不过卡尔丹诺并不是平衡环架的发明者，他也未如此声称。平衡环架自古即出现，很难归因于谁的发明。

A gimbal is a pivoted support that allows the rotation of an object about a single axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow an object mounted on the innermost gimbal to remain independent of the rotation of its support (e.g. vertical in the first animation). For example, on a ship, the gyroscopes, shipboard compasses, stoves, and even drink holders typically use gimbals to keep them upright with respect to the horizon despite the ship's pitching and rolling.