The earliest ancestor of the modern-day Daft Punk helmet came in 1997's Michel Gondry-directed "Around the World" video, when four walking robots were used to keep time in a choreographed dance. Then, September 9, 1999 was the day Daft Punk announced that they had become robots. It was the result of a spirited vision for the band's future and led to a deeply-orchestrated effort to design their new look.
These helmets had to be functional props, not just for decoration but furthermore able to be performed with. They would become the face of the band, and as such they had to express all the emotion the band wanted to impart in any situation. This short Mixmag documentary produced by Jemayel Khawaja gives a lot of insight into the design and creation of these helmets, which inspired future electronic acts like deadmau5 and marshmello.