How do AT-TE Walkers climb vertical cliffs?

In Star Wars: The Clone Wars TV series, AT-TE Walkers were able to climb vertical walls like lizards (Battle of Teth). You can also see it in Star Wars: The Clone Wars video game.

What mechanism in their legs facilitates this vertical climbing? Vacuum, mechanical drill grips or something else?

• Definitely non-canon, but DARPA has been doing research on how gecko's grip surfaces, apparently they do it by utilising inter-molecular forces. scientificamerican.com/article/how-geckos-get-a-grip – Jaydee Dec 12 '14 at 9:47
• Really? gizmodo.com/… That's almost 260 pounds on two climbing paddles on a 25 ft glass wall. – Jaydee Dec 12 '14 at 10:11
• At the moment, but with centuries of research... – Jaydee Dec 12 '14 at 10:18
• You were asking about possible mechanisms for a fantasy vehicle to climb vertical walls. A modified development of the gecko's foot idea that depends on inter-atomic or inter-subatomic forces would easily be able to support the weight of a large vehicle or even many of them. – Jaydee Dec 12 '14 at 10:56
• @Jaydee Based on test results in 2012 darpa.mil/Our_Work/DSO/Programs/Z_Man.aspx A 16 in^2 sheet of that material supported 660 pounds. Based on the area of the AT-TE feet from answers to scifi.stackexchange.com/questions/66096/… then we have 1.75 sq meters per foot, which if covered in the stuff would support 111870 lbs, or 50 metric tons. At least 3 feet of the AT-TE on the wall would mean 150 metric tons of support, which is less weight than the best answer for the afore mentioned question states. So in Earth like gravity, geckskin would work. – Firebat Dec 13 '14 at 16:59