the expedition mechanic is automated at the end of turn with random ranges for seeds, research and spare parts, i ran out of game jam time so couldn't have it as a gameplay mechanic as originally wanted.
Had to seriously down scope the project to meet the deadline.
funny enough focusing on food until the food icon in the right goes green is a good tactic as you never lose a shelter member, after turn 20 you can start to gain survivours who want to join.