I am using Google ortools for CVRP. I have constraints on both vehicle capacity and max distance (in reality, it’s a max travel time constraint, but I’m formulating it as a distance constraint). Both constraints are holding. The issue is that my max travel time constraint, in real life, is a goal: at least XX% of routes under the maximum time. So I don’t need 100% of the routes to meet this constraint, but X% – and in fact, if 100% of the routes were under it then that may be suboptimal for the business.

Is there a way to express this goal in ortools or do I just need to fiddle around with the max time constraint and hope for the best?