Are Ball Shaped Wheels Practical

Get your first 10 PCBs for free at A few years ago, Goodyear produced a concept for a tyre, which was a ball. But are ball shaped wheels practical, and can we make a vehicle or robot with ball shapes omniwheels I found a video about research carried out at Osaka University, where an omniball wheel is made in two halves and seems to work well. But is there more to it I made my own prototype with 3D printing, in both rigid PLA and TPU. Each hemisphere rotates around a smaller wheel which is oriented with the main drive