I want to share with you some of my recent experiences with two field service technicians – one for my fridge, the other for my cable. Both technicians were scheduled to arrive on the same day. The cable guy was supposed to come between 11:00 and 13:00 and the fridge guy – between 13:00 and 15:00. Surprisingly – none of them was late.
In fact, they were both early. Very early…
The cable guy called me at 8:00 (!) and informed me that he would be at my house within 30 minutes. Luckily, I was home (and awake) so this sudden change of plans was OK by me. Next, the fridge guy called me at 10:30 and informed me that he was coming. Since the cable gay had already left, this was, again, OK by me. However, a significant question came up to mind:
What just happened here? What made the technicians change their schedule?
Frankly, I cannot know. Maybe they had some cancelations. Perhaps the service of the previous customer in the schedule was shortened. Perhaps they just decided not to follow the schedule. And the technicians were early, not late. That’s good, right?
Well, not really. Had I been asleep, or outside of my home at 8:00, this sudden change of plans could have caused problems. Field service personnel can and should arrive at their pre-committed time windows. Technician that shows up way before his time window can be just as bad as a technician showing up way after that window.
So, how can we make sure that we provide high service levels, that is, arrive at the customers at their pre-committed time windows while maximizing the utility of the technicians, that is, busy and not idle?
The answer to this question lies in dynamic and online scheduling. That is, the technician schedule is modified as his working day progresses to accommodate for the real-life occurrences.
This is our mission.