Tesla plans to use its Model S and X production lines to manufacture its robots, known as Optimus. (AP PHOTO)Tesla plans to use its Model S and X production lines to manufacture its robots, known as Optimus. (AP PHOTO) Credit: AAPTesla is set to discontinue its larger electric car models, the Model S and Model X, to free up capacity for robot production. The Model X, known for its falcon-wing doors, followed in 2015. Tesla plans to use the existing production lines for the Model S and Model X to manufacture its humanoid robots, known as Optimus.