A few months ago, I tried to read the "The Way of Kings" novel series by Brandon Sanderson. One plot device is a war conducted on the Shattered Plains, a series of plateaus separated by deep chasms 3 to 10 meters wide, requiring adapted warfare tactics.

One instrument used in this challenging environment is a one-piece mobile bridge transported by slaves, but it is employed in a baffling manner :
- The bridge is massive, requiring at least 25 of its 40 men crew to lift it.
- The porters are not protected against projectiles, via either structural or personal armor.
- The bridges are sent towards enemy positions without suppressing fire, resulting in a fatality rate of at least 25% for each run.

This waste of resources and manpower spurned me to design a mobile bridge which could protect its movers during transport and deployment. It is based on Pasos (Spanish man-carried floats for religious processions) and uses twin lead-screws coupled with a pantograph mechanism.