Home assistant robots must navigate the complex, cluttered, and constantly changing environment of a lived-in home. They use LiDAR, cameras, and depth sensors to build and continuously update maps of the home interior, handling furniture rearrangements, opened or closed doors, and transient obstacles like shoes and toys. Path planning must account for the robot's size (including any carried objects), doorway widths, carpet transitions, and areas where humans are present. Advanced systems create semantic maps that understand room functions — knowing the kitchen from the bedroom enables context-appropriate behavior like adjusting movement speed or interaction style.