spatial

JAX visitors for spatial expressions.

Visitors: QDCM, SSMP, SSM

Lowers the 6-DOF rigid-body primitives to JAX functions that build small matrices from their operand vectors: QDCM turns a (normalized) quaternion into a 3x3 direction-cosine matrix, SSM builds the 3x3 skew-symmetric (cross-product) matrix of a 3-vector, and SSMP builds the 4x4 matrix used in the quaternion kinematics q_dot = 0.5 * SSMP(omega) @ q. These are the building blocks for attitude and spacecraft/robotics dynamics.