On Carambat’s Instagram, you can check out videos of the process. The four thrusters on the robot blow smoke and strobe, and the arms move up and down via the controllers. The torso serves as the steering mechanism, while an old electric wheelchair forms the base. The guns rotate, and the lights change color when the guns are fired. The mech also features a sound system with D.Va voiceovers, a rear hatch to help the pilot get out, and even a fan to keep the pilot cool.
(Update 3:14 July 25th — The Facebook videos have been moved to a YouTube playlist.)
According to his Instagram, Carambat had wanted to build the mech for a long time, but started on the design back in January. He estimates the mech cost under $1000 to make. His daughter Amanda will use this mech for her cosplay as D.Va.