Create 3 is iRobot’s educational robotics platform — the same round chassis and Roomba i3 drivetrain as their consumer vacuums, sold bare as a development base with a full ROS 2 software stack instead of a cleaning routine. A bump ring, cliff sensors, IR proximity sensors, and an IMU give it the sensing a real vacuum needs to navigate a room.
The mechanism
Two continuous wheel joints are the robot’s only real actuated DOF — a textbook
differential-drive base. Each wheel also rides a spring-loaded suspension joint (a real
prismatic joint with spring/damper dynamics, not <mimic>-driven) that lets the physical
robot sense being lifted off the ground; it’s a passive mechanism, not a second motor, so it
isn’t counted toward the two degrees of freedom. A free-spinning front caster and every
sensor/button on the body are fixed reference frames with no motion of their own.
About these files — read before importing
This links directly to create3_sim, iRobot’s own repository, published under their GitHub Education organization. ARMOR links directly to that repository rather than re-hosting anything, so what you get is exactly what iRobot publishes, unmodified.