Lecture 8.1. Wherein rigid body displacements are described in homogeneous form as matrices. Rotation and translation are brought together to fight for the good. Displacement matrices behave much like rotation matrices but with some caveats. Displacement change of frame is treated. This lecture was recorded at Saint Martin's University in the Spring 2021 term as part of the course lrpk (see the course website http://ricopic.one/courses/robotics-p.... It is the property of the instructor Dr. Rico Picone.