gimbal locks

Noun

gimbal lock (countable and uncountable, plural gimbal locks)

1. The loss of one degree of freedom in the three-dimensional rotational movement of a three-gimbal mechanism, which occurs when the axes of two of the three gimbals are driven into a parallel configuration, so that the system's rotational movement becomes two-dimensional (and necessarily remains so until an appropriate force is applied); the equivalent situation in a simulation of rotational movement, when the mathematical model uses Euler angles (representing pitch, yaw and roll) or their equivalent.
   • Gimbal lock occurs when the pitch nears 90° or 270°, causing the bank and heading to lie along the same plane. This limits the item to only two rotation axes, as the bank and heading effectively do the same thing.2005, Jonny Gorden, LightWave 3D 8 Cartoon Character Creation, Volume 2: Rigging and Animation, Wordware Publishing, page 126