they are Idea Sketches (for Wall-E promotion poster).
Personally, I like those - #5, #10, #8, #16.
Three works of sketches adopt rough sketch.
1. Making Speech Buble
Carving Wall-E's body
expressing at Pot of the Plant (Movie Wall-E's foreshadowing)
At Final works, I retouched QR code and QR powders with brown.
Thank You !