Activity.md

Activity

Describe where an activity take place, when it can be performed and how long it last.

{
  "activity": {
    "point_id": "visit-point",
    "timewindows": [{
      "start": 3600,
      "end": 4800
    }],
    "duration": 2100.0
  }
}

The available parameters are the following :

• point_id allows to designate the point where the activity takes place
• duration represents the uncompressible duration of the activity
• setup_duration represents the compressible duration in case of successive activities performed at the same point
• timewindows are the time slots where activities may be performed
• late_multiplier represents the tolerance to lateness. It is a cost applied by second of violation (0 means no lateness).
• position forces the activity to a given position into the route.

point_id

It should refer to the id of point defined in the points field belonging to the vrp.

{
  "vrp": {
     "services": [{
        "id": "visit-1",
        "activity": {
          "point_id": "visit-point-1"
        }
     }],
     "points": [{
       "id": "visit-point-1",
       "location": {
         "lat": 49.0,
         "lon": 1.0
       }
     }]
  }
}

duration

It represents the time required to perform the current and specific activity. It could depend on the vehicle if the fields coef_service or additional_service are defined by the vehicle which is assigned to perform the activity in the solution.

{
   "services": [{
    "id": "visit-1",
    "activity": {
      "point_id": "visit-point-1",
      "duration": 600.0
    }
  }, {
    "id": "visit-2",
    "activity": {
      "point_id": "visit-point-1",
      "duration": 600.0
    }
  }]
}

setup duration

When multiple activities are performed at the same location in a direct sequence it allows to have a common time of preparation. It Could be assimilated to an administrative time.

{
  "services": [{
    "id": "visit-1",
    "activity": {
      "point_id": "visit-point-1",
      "duration": 600.0,
      "setup_duration": 1500.0
    }
  }, {
    "id": "visit-2",
    "activity": {
      "point_id": "visit-point-1",
      "duration": 600.0,
      "setup_duration": 1500.0
    }
  }]
}

If those two services are performed in a row, the cumulated time of activity will be : 1500 + 600 + 600 = 2700 instead of 4200 if the two duration were set to 2100.

timewindows

{
  "services": [{
    "id": "visit-1",
    "activity": {
      "point_id": "visit-point-1",
      "timewindows": [{
        "start": 3600,
        "end": 4800
      }],
      "duration": 600.0,
      "setup_duration": 1500.0
    }
  }, {
    "id": "visit-2",
    "activity": {
      "point_id": "visit-point-1",
      "late_multiplier": 0.3,
      "timewindows": [{
        "start": 3800,
        "end": 5000
      }],
      "duration": 600.0,
      "setup_duration": 1500.0
    }
  }]
}

late_multiplier

It represents the cost applied for each second arrived late to start the activity.

{
  "services": [{
    "id": "visit-1",
    "activity": {
      "point_id": "visit-point-1",
      "late_multiplier": 0.3,
      "timewindows": [{
        "start": 3600,
        "end": 4800
      }],
      "duration": 600.0,
      "setup_duration": 1500.0
    }
  }, {
    "id": "visit-2",
    "activity": {
      "point_id": "visit-point-1",
      "late_multiplier": 0.3,
      "timewindows": [{
        "start": 3800,
        "end": 5000
      }],
      "duration": 600.0,
      "setup_duration": 1500.0
    }
  }]
}

Note that, by default a maximum lateness value is fulfilled (depending on the server configuration) to limit the maximum lateness to 100% of each timewindow. Having a timewindow with a span of 1 hour. You could refer to Lateness for more details.

position

position field allows user to provide an indication on when service activity should take place among one route. Several values are available for this parameter :

• neutral (default value) : service can take place at any position of the route,
• always_first : service should take place at the beginning of the route that is to say in first position or among other services with this constraint, at the beginning of the route.
• always_last : service should take place at the end of the route that is to say in last position or among other services with this constraint, at the end of the route.
• always_middle : service should not be in first or last positions of the route.

The available values are : neutral, always_first, always_middle, always_last, never_first, never_middle, never_last).

{
  "services": [{
    "id": "visit-1",
    "activity": {
      "point_id": "visit-point-1",
      "position": "always_first"
    }
  }, {
    "id": "visit-2",
    "activity": {
      "point_id": "visit-point-1",
      "position": "always_first"
    }
  }]
}

Note that if multiple activities of different services have the same position, the solution will keep these activities grouped a the given position.