Answer Wiki. The system would be cued off the pilot's helmet, so it will definitely look where your head is pointing, not your eyes specifically (that would be a gaze-tracking system, which AFAIK hasn't yet been used for this kind of application).
Exercise to Gain Leg Weight. Although you can't make your body gain weight in your legs, you can perform exercises that encourage the growth of leg muscle. Squats, lunges and step-ups are examples of such moves that target the legs and recruit a lot of muscle fibers for growth.
Step Up Your Game. To build thick, strong legs, do step-ups, which are an incredibly effective resistance exercise. Stand up straight with a narrow stance in front of a step. For big muscle gains, it's best to use a step high enough so that your leg forms a right angle when you step up onto it. Hold a dumbbell in each hand and extend your arms straight down at your sides. Step up with your left foot, then with your right foot and then step back down, starting with your right foot.