What else does Martinez do?

Everyone has at least two specialties on Ares 3: Lewis is the Commander and geologist; Beck is the doctor, biologist, and the EVA specialist (overachiever much); Johansson is the reactor tech and sysop; and Watney is the mechanical engineer and botanist. But Martinez is just the pilot which, granted, includes the MAV, MDV, and Hermes but I feel like Hermes handles itself mostly on autopilot and normal missions don't include docking with extra supply probes so what else does Martinez do? The MAV and MDV only take one day each and I feel like he doesn't have a science schedule like the rest of them. Is he just like everyone's assistant when he isn't actually piloting things?