Attached Link: Gimbal lock and Euler angles

Spit, Gimbal lock occurs in all Poser objects, because they all use a 3 channels rotation system. The Body of Posette, for example, has rotation order yRotate xRotate zRotate. Whenever you set the middle rot channel (xRotate) of Body to 90 or -90, you lose a rotation axis (yRotate and zRotate have same rotation axis). All 3D apps with 3 parameter rotation system generate gimbal lock effects. To avoid gimbal lock in Poser, you can add an additional rot channel (then you have a 4 channel rotation system). You find some more information in post #11 of the above message.