I am intrigued with the woven tubing muscle I thought of. I will have to experiment with some of these and see if they offer any real advantages. Lets assume that the leg muscles are the strongest muscles in our robot. The leg muscle will have to lift the entire weight of the robot and load. Assume a foot one-foot long.
Lets hook the calf muscle to the heel two inches behind the ankle.
If we use 100-PSI air pressure that works out to about 17 square inches. An air bag working through a lever may be the best choice for this. Based on my personal convictions, I feel that the fuel should be renewable. In terms of handling, liquid fuel is the only way to go. When you talk about renewable liquid fuel that pretty much describes alcohol.