This drawing shows the waist assembly. Its main purpose is to look kind-of bad-ass. The functional aspects of this assembly are marginal at best.
The front panel contains a hole which can be used as a viewport and access panel to the inside of the robot. It is largely decorative in nature.
This drawing is of the acrylic panel which fits into the front panel and provides a way to see inside the internals of the robot. Its primary purpose is to be the ooh, look, a robot! aspect of the robot.
This drawing is of the waist side-panels. It provides a kind-of futuristic side-panel vent which is typical in lots of science-fiction robots, but provides no useful purpose.