Mecanum and Omni wheels
Here is a video explaining the concept and difference. Google "omni wheels vs mecanum wheels" for a good AI explanation.
Here are a couple of affordable robot kits:
- mecanum wheel starter kit
- omni wheel starter kit
A project by Proto G Engineering - converting hoverboard motor wheels into mecanum wheels:
- short videos: https://youtu.be/abPLaRr66IM and https://youtu.be/QXF6hNVUydI
- Thingiverse files
- strong 96 mm mecanum wheels
LeKiwi Low-Cost Mobile Manipulator under ROS by Nathan Lewis:
For tips and software for BLDC motor wheels visit this guide and take a look at Seggy robot.