This was a kids sci-fi movie from the 1980s. It may have been live action. The scene I remember most was a young kid wearing futuristic clothing or a uniform and was accompanied by a furry, three-legged “pet” with a big mouth. (The creature may was a muppet, NOT computer animated.)
They were in an arid region and the three-legged creature was hanging from a tree. The kid was looking to see where to go next and instructed the creature to check out ahead. The creature dropped from the tree and began running by tumbling on all three legs until it was moving like a wheel and at a very high rate of speed.
Now I’m wondering if it was animated. But for some reason I remember being amazed at how they filmed the creature rolling/running with 3 legs.
Let me know if this wasn’t my own imagination. Thanks!