Creating a rough 3D model of our robot with URDF

Using URDF we can quickly rough out a 3D design for our robot, that we'll soon be able to use for simulations.
Companion blog post available at https://articulatedrobotics.xyz/mobile-robot-2-concept-urdf/

TF Overview https://youtu.be/QyvHhY4Y_Y8
URDF Overview https://youtu.be/OWeLUSzxMsw

Commit at this stage https://github.com/joshnewans/articubot_one/tree/d5aa5e9bc9039073c0d8fd7fe426e170be79c087
Inertial macros file https://github.com/joshnewans/articubot_one/blob/d5aa5e9bc9039073c0d8fd7fe426e170be79c087/description/inertial_macros.xacro

00:00 - Intro
00:40 - Differential Drive Concept
02:12 - Prep steps
02:43 - Recap of important ideas
04:22 - Creating a core file and base link
08:54 - Chassis
12:35 - Drive Wheels
17:55 - Caster Wheel
20:11 - Collision Geometry
21:22 - Inertia
25:10 - Save & Wrap up