I am very keen on having four wheel pairs that are powered by one motor each. So four Motors, 8 wheels. The next part of my design would be in trying out different approaches to achieve this. Being a 3d printing veteran I have many GT2 Pulleys and belts laying around and so my first thought is to grab some of those and see if I can make something work with what I have.
My first iteration was what you see above. I used pulleys to ‘pinch’ the belt around each wheel to maximize the contact surface and hopefully reduce slipping. I also added a slider (slot on the left) to add a tensioning pulley as well to make sure the arrangement stayed tight.
Iterate, Iterate Iterate, The more I play with the design, the more I wanted to change it, I found calculating the required belt lengths very difficult with the complex arrangement and the resulting trial and error quite difficult. I wanted to try and maintain the size of my design but making things fit was a squeeze.
In the end I found the arrangement above to work quite well – if I could stop the pulleys from toppling over before putting the top on. I was happy enough to live with it for the moment until the wheels arrived ….