CarSource

CarSource is the block that generates cars and tries to put them into the specified location within a road network. This block has no buffer, so if the car is not generated at the appropriate time, it will not be generated later.

The car can appear on the specified road or in the specified parking lot (defined by the Appears parameter).

Car arrivals can be defined by:

• interarrival times,
• arrival rate,
• rate schedule,
• arrival schedule that defines the exact number of cars and times of their arrival,
• calling the inject() function of the CarSource block.

As in the Source block, you can limit the number of arrivals.

If you want cars to appear on a road, you should also specify the direction of the road. The cars will appear at the beginning of the specified road and start moving in the specified direction. By default, the Random lane parameter is selected, so the cars will appear at random lanes (if there is more than 1 lane in the specified direction on the road). You can explicitly specify the index of the lane where cars will appear by clearing the Random lane option and using the Lane index parameter.

If cars are set to appear in a parking lot, they appear in free spaces of the specified parking lot and wait until they leave the road network or start moving by entering the CarMoveTo block. If all parking spaces are occupied, an error is generated.

Arrivals defined by

Specifies the mode of cars generation:

Rate — Cars are generated at the specified Arrival rate (which is equivalent to exponentially distributed interarrival time with mean = 1/Arrival rate).
Interarrival time — The time between two consecutive cars is defined by the specified expression.
Arrival table in Database — Cars are generated according to the records in the specified database table. You specify the table below in the Database table parameter, then select the table column containing the arrival moments in the Arrival date drop-down list. The block will generate one car for each data record in the specified table.
Rate schedule — Cars are generated according to the schedule that defines how the Arrival rate of cars changes over time.
Arrival schedule — Cars are generated at exact times defined in the arrival schedule.
Calls of inject() function — Cars are not generated automatically, but only when the inject() function is called.

Name: arrivalType
Type: RoadTrafficLibraryConstants.ArrivalType
Set new value at runtime: set_arrivalType(new value)
Valid values:
CarSource.RATE — Rate
CarSource.INTERARRIVAL_TIME — Interarrival time
Source.DATABASE_ARRIVAL_TABLE — Arrival table in Database
CarSource.RATE_SCHEDULE — Rate schedule
CarSource.ARRIVAL_SCHEDULE — Arrival schedule
CarSource.MANUAL — Calls of inject() function

Arrival rate

[Visible and applies only if Arrivals defined by: Rate]
The arrival rate of cars. If Arrival rate is used and it becomes 0, no next arrival will be scheduled until the Arrival rate changes to a positive value.

Name: rate
Type: double
Default value: 1000 per hour
Set new value at runtime: set_rate(new value)

Interarrival time

[Visible and applies only if Arrivals defined by: Interarrival time]
The expression used to evaluate the delay time for each arriving car.

Type: double
Default value: 10 seconds

Arrival schedule

[Visible and applies only if Arrivals defined by: Arrival schedule]
The name of the schedule with integer value type that contains the arrival times of the cars. Typically, the value column would contain 1 as one car is generated at a time.

Name: arrivalSchedule
Type: Schedule<Integer>
Set new value at runtime: set_arrivalSchedule(new value)

Arrival date

[Visible if Arrivals defined by: Arrival table in Database]
Specify the column of the Database table that contains the agent arrival timestamps. To access the field, first, specify the database table in the property above.

Type: Date

Rate schedule

[Visible and applies only if Arrivals defined by: Rate schedule]
The name of the schedule defining how the Arrival rate of cars changes with time.

Name: rateSchedule
Type: Schedule<Integer>
Set new value at runtime: set_rateSchedule(new value)

Database table

[Visible and applies only if the Arrivals defined by: Arrival table in Database, or the Set agent parameters from DB option is selected]
Here you can choose the database table containing the data about arriving cars.

Name: databaseTable
Type: TableInput
Set new value at runtime: set_databaseTable(new value)

Modify rate

[Visible and applies only if Arrivals defined by: Rate schedule]
Toggles the expression that modifies Arrival rate. The expression is defined in the Rate expression property below.

Name: modifyRate
Type: boolean
Set new value at runtime: set_modifyRate(new value)

Rate expression

[Visible and applies only if the Modify rate option is selected]
The expression that modifies the arrival rate.

Type: double
Local variable: double baseRate — the current rate value taken from the specified rate schedule

Set agent parameters from DB

[Visible and applies if the Arrivals defined by option is not set to Arrival table in Database or Calls of inject() function]
If the option is selected (true), enables initialization of car parameters from the specified Database table.

Name: setAgentParametersFromDB
Type: boolean
Set new value at runtime: set_setAgentParametersFromDB(new value)

Limited number of arrivals

[Visible and applies if the Arrivals defined by option is not set to Calls of inject() function or Arrival table in Database]
If selected (true), the number of arrivals will be limited to Maximum number of arrivals.

Name: limitArrivals
Type: boolean
Set new value at runtime: set_limitArrivals(new value)

Maximum number of arrivals

[Visible and applies only if the Limited number of arrivals option is selected]
The maximum number of cars to be generated by this block.

Name: maxArrivals
Type: int
Set new value at runtime: set_maxArrivals(new value)

Appears

Specifies where the cars generated by this block will appear: on a road or in a parking lot.

on road — The cars will be placed at the beginning of the road specified below in the Road parameter.
in parking lot — The cars will be placed in a randomly chosen free parking space of the parking lot specified below in the Parking lot parameter.

Name: appears
Type: RoadTrafficLibraryConstants.CarOriginType
Set new value at runtime: set_appears(new value)
Valid values:
CarSource.ON_ROAD — on road
CarSource.IN_PARKING_LOT — in parking lot

Road

[Visible and applies only if Appears: on road]
The road on which the car will be placed after the start of the movement. The car enters the Road in the specified lane (forward lane or backward lane). The lane is specified by the Enters parameter below. The lane is picked randomly (if the Random lane option is enabled) or specified explicitly at the Lane index parameter below.

Type: Road
Local variable: T car — the car that is being created by this block

Enters

[Visible and applies only if Appears: on road]
Specifies the lane (forward lane or backward lane) of the road in which the car will be placed. If the road does not have the specified lane (that is, is one-way), the error is generated.

Name: laneDirection
Type: RoadTrafficLibraryConstants.CarRoadDirection
Set new value at runtime: set_laneDirection(new value)
Valid values:
CarSource.FORWARD_LANE — forward lane
CarSource.BACKWARD_LANE — backward lane

Lane selection policy

[Visible and applies only if Appears: on road]
Specifies the policy by which a lane is selected for placing the car. This policy remains in effect as the car passes through subsequent blocks, unless one of those blocks specifies a different policy. The following options are available:

Random lane — Places the car in a random lane. Selected by default.
Closest to median — Selects the lane closest to the median. For one-way roads, this is the outermost lane on the left (right-hand traffic) or on the right (left-hand traffic).
Closest to roadside — Selects the lane closest to the roadside. For one-way roads, this is the outermost lane on the right (right-hand traffic) or on the left (left-hand traffic). When this option is selected, the Number of lanes property determines how many lanes from the roadside are considered. The specific lane for each car is chosen randomly among these lanes.
Specified explicitly — Places the car on a specified lane, defined by the Lane index property.

Name: laneSelectionPolicy
Type: RoadTrafficLibraryConstants.LaneSelectionPolicy
Set new value at runtime: set_laneSelectionPolicy(new value)
Valid values:
CarSource.LANE_RANDOM — Random lane
CarSource.LANE_MEDIAN — Closest to median
CarSource.LANE_ROADSIDE — Closest to roadside
CarSource.LANE_EXPLICITLY — Specified explicitly

Number of lanes

[Visible and applies only if Lane selection policy: Closest to roadside]
Specifies how many lanes from the roadside edge are considered. The roadside lane is the outermost lane on the right (right-hand traffic) or on the left (left-hand traffic). The car is placed on a randomly selected lane among the specified lanes, starting from the roadside. The specified number may exceed the actual number of lanes on the road; in this case, any available lane is used.
The value must be a positive integer greater than zero.

Type: int
Local variable: T car — the car being created by this block

Lane index

[Visible and applies only if Lane selection policy: Specified explicitly]
Specifies the index of the lane where the car should be placed. Lane indices start at 0 (the outermost lane) and increase toward the innermost lane. If the specified Road does not have a lane with the given index, an error is generated.
Prior to AnyLogic 8.9.7, this property affected only the lane in which the car initially appeared. After creation, the car could move to any other lane. Starting with AnyLogic 8.9.7, the Specified explicitly policy also applies to subsequent movement. The car will attempt to stay in or return to the specified lane if it temporarily leaves it (for example, due to a turn or a road segment with fewer lanes).
To generate a car in a specific lane and allow it to change lanes freely, add a CarMoveTo or CarEnter block with the Lane selection policy set to Random lane.
The policy is flexible: if the car prefers a certain lane (for example, the second) and enters a one-lane segment, a warning will be displayed, but the car will continue moving. Once multiple lanes become available again, the car will return to the preferred lane.

Type: int
Local variable: T car — the car being created by this block

Parking lot

[Visible and applies only if Appears: in parking lot]
The parking lot where the car will be placed immediately after entering this block. If the parking lot has no free spaces, an error will be generated. The car will not move from the parking space until it is sent to a destination by the CarMoveTo block.

Type: ParkingLot
Local variable: T car — the car that is being created by this block

New car

The car type created by this CarSource block. Use an agent type with the Use in flowchart as property set to Car.

Type: Agent

Length

The length of the generated car. The length must be greater than zero.

Type: double
Default value: 5 meters
Local variable: T car — the car that is being generated by this block

Initial speed

The initial speed of the generated car. The initial speed must be greater than or equal to zero. If the initial speed is less than the preferred speed, the car will start accelerating to its preferred speed when it is sent to a destination by the CarMoveTo block.

Type: double
Default value: 60 kilometers per hour
Local variable: T car — the car that is being generated by this block

Preferred speed

The preferred speed of the generated car. The preferred speed must be greater than or equal to zero. If the preferred speed is equal to 0 and the initial speed is equal to 0, the car will not start movement even if it is sent to a destination by the CarMoveTo block. The car will not start accelerating until it is assigned a positive initial speed by the call of the setPreferredSpeed(speed) function.
The car will always try to move at a speed equal to its preferred speed. The following factors can prevent the car from moving at its preferred speed:

• the inability to accelerate or decelerate immediately to the preferred speed,
• a car ahead that is moving slower than the preferred speed of the car,
• a stop line with a red light ahead,
• the proximity of a parking space or bus stop, where the car should slow down to park or stop,
• the speed limit.

Type: double
Default value: 60 kilometers per hour
Local variable: T car — the car that is being generated by this block

Max acceleration

The maximum acceleration of the generated car. The acceleration should be greater than zero.

Type: double
Default value: 1.8 meters per second²
Local variable: T car — the car that is being generated by this block

Max deceleration

The maximum deceleration of the generated car. The maximum deceleration should be greater than zero. The car will use its maximum deceleration only in emergencies. At other times it will use a fraction of the maximum deceleration.

Type: double
Default value: 4.2 meters per second²
Local variable: T car — the car that is being generated by this block

Add cars to

This parameter specifies where the cars created by this block will be stored: in the default population of root agent or in some custom population (specified below in the Car population property).

Name: addCarToCustomPopulation
Type: boolean
Set new value at runtime: set_addCarToCustomPopulation(new value)

Car population

[Visible and applies only if the Add cars to: custom population option is selected]
The name of the agent population where the cars created by this block will be stored.

Type: <Agent> List
Local variable: T car — the car that is being created by this block

On exit

The code that is executed when car exits this block.

Local variable: T car — the car that exits this block

out

The output port.

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