RackStore

RackStore puts agent into a cell of a given pallet rack, or RackSystem. The agent is moved from its current location in the network to the cell location, optionally with the help of moving resources. Optionally, a delay may be associated with putting an agent into a cell; the delay may depend on the cell coordinates, e.g. on its level.

The cell may be specified explicitly as (row, position, level) or chosen automatically. In the latter case RackStore uses the function getFreeCell() of the storage or storage zone.

If resources are used to move the agent, RackStore seizes them, brings to the agent location, attaches to the agent, moves the agent to the cell, executes (an optional) delay, and then releases the resources. Alternatively you can seize and release resources outside the RackStore block, or not use them at all.

You can choose whether the agent (possibly, with the attached resources) moves smoothly all the way along the aisle and then from the aisle to the cell, or moves just along the aisle and then jumps to the cell. The latter case may be useful when animating automated storages.

RackStore exposes a number of extension points to insert your custom actions at different stages of the process.

When the agent exits the RackStore block it is stored in a storage cell. If this is a final point of your agent-related process, i.e. if there is no direct continuation from here, you can put a “blank” Exit block after RackStore, but you should not leave its out port unconnected. Putting Sink instead of Exit would not be correct, as the agent remains in the system.

Pallet rack / Rack system

Pallet rack, or storage zone (defined by block RackSystem), where the agent should be put.

Local variable: agent — the agent.

The cell is

Defines whether the cell for the agent is Chosen automatically, or the cell should be Specified explicitly by the user.

Syntax: boolean autoChooseCell
Local variable: agent — the agent.
Default value: Chosen automatically (true)

Choose cell closest to

[Visible if The cell is Chosen automatically]
Defines, whether the cell is chosen closest to Front of storage/zone, or — to Back of storage/zone.

Syntax: boolean closeToFront
Default value: Front of storage/zone (true)

Row

[Visible if The cell is Specified explicitly]
The row of the cell.

Value type: int
Local variable: agent — the agent.

Position

[Visible if The cell is Specified explicitly]
The position of the cell.

Value type: int
Local variable: agent — the agent.

Level

[Visible if The cell is Specified explicitly]
The level of the cell.

Value type: int
Local variable: agent — the agent.

For two-aisle racks

[Visible if The cell is Specified explicitly]
Choose how you want to store agents in the two-aisled pallet rack:

Put from left aisle
Put from right aisle

Value type: boolean
Default value: Put from left aisle (true)
Local variables:
agent — the agent
RackSystem rackSystem — the rack system
PalletRack palletRack - the pallet rack

Move agent to

Moves the agent to the defined destination: Cell (with elevation), Cell base level, or Aisle.

Get value: movementDestination
Default value: Cell (with elevation) (RackStore.DEST_CELL_LEVEL)

Elevation time per level

[Visible if Move agent to is defined by Cell (with elevation)]

Value type: double
Default value: 10 seconds
Local variable: agent — the agent

Use delay

If the checkbox is selected (true), the delay is executed after the agent arrives to the cell and before it is actually put there.

Syntax: boolean useDelay
Default value: false

Delay time

[Visible if Use delay is selected]
Expression evaluated to obtain the delay time for the agent.

Value type: double
Local variables:
agent — the agent
RackSystem rackSystem — the rack system
PalletRack palletRack - the pallet rack
int row — the row of the cell
int position — the position of the cell
int level — the level of the cell

Agent location (queue)

Space markup shape for queue.

Name: entityLocationQueue

Use resources to move

If the checkbox is selected (true), the specified moving resources are used to move the agent.

Syntax: boolean useResources
Default value: false

Resource sets (alternatives)

[Visible if Use resources to move is selected] Here you define set(s) of the required resources. You can define several alternative resource sets (add new list by clicking the Add list button). The resource set is chosen based on the availability of units. For more information, see Resources.

Local variable: agent — the agent

Move at the speed of resource

[Visible if Use resources to move is selected]
If selected (true), the agent moves with the specified moving resources speed.

Syntax: boolean moveWithSpeedOfResourceUnit
Default value: false

Moving resource

[Visible if Move at the speed of resource is selected]
If true, the specified moving resources are used to move the agent.

Value type: ResourcePool
Local variable: agent — the agent

Task priority

[Visible if Use resources to move is selected]
The priority of the task for the incoming agent (the larger the higher).

Value type: double
Default value: 0
Local variable: agent — the agent

Task may preempt

[Visible if Use resources to move is selected]
If selected, task may preempt the currently performed task (if allowed in the task properties & the task priority is lower).

Value type: boolean
Default value: true
Local variable: agent — the agent

Task preemption policy

[Visible if Use resources to move is selected] Defines the task preemption policy:

No preemption — the current task continues executing.
Wait for original resource — the task is interrupted and waits for the same resource unit to finish it.
Terminate serving — the task is interrupted and never continued.
Seize any resource — the task is interrupted and tries to seize any resource of the specified type.
Continue without resource — the task is finished without resources assistance.

Default value: No preemption
Valid values:
RackStore.PP_NO_PREEMPTION
RackStore.PP_WAIT_FOR_ORIGINAL_RESOURCE
RackStore.PP_TERMINATE_SERVING
RackStore.PP_SEIZE_ANY_RESOURCE
RackStore.PP_CONTINUE_WITHOUT_RESOURCE
Local variable: agent — the agent.

Auto suspend/resume agents

[Visible if Task preemption policy is to Wait for original resource or to Seize any resource]
This parameter defines whether the agent whose task is suspended should be automatically suspended in its current flowchart block and automatically resumed at the time there are available resources.

Syntax: boolean suspendResumeEntities
Default value: true

Enter for terminated agents

[Visible if Task preemption policy is to Terminate serving]
Enter block for agents which lose all units obtained in this Seize block because of Terminate serving preemption policy, when one of units in the resource set (defined in this Seize) gets grabbed by another task with higher priority.

Local variables:
agent — the agent
Agent unit — the resource unit which has originated termination

After release resources

[Visible if Use resources to move is selected]
Defines whether resources should Return to home location (if they are not immediately seized by another agent) or Stay where they are after being released.

Syntax: boolean resourcesGoHome
Default value: Return to home location (true)

Return home

[Visible, if After release resources: Return to home location]
Here you select in what case resource units will return home after performing the “put agent into a pallet rack cell” task.
There are three alternative options:

each time — resource unit will return in its home location each time this resource unit finishes the task and is released by the agent.
if no other tasks — resource unit returns in its home location only if there are no other tasks currently waiting for this resource unit.
custom — if you select this option, you can define the priority and preemption policy for “return home” task using the parameters below. In this case the priority of the “return home” task will be compared with priorities of other incoming tasks, and the specified preemption policy will be used to select the next task for this particular resource unit.

Local variables:
agent — the agent
Agent unit — the resource unit

'Wrap-up' priority

[Visible, if Return home: custom]
Here you can set up the priority of the “return home” task for the resource unit.

Value type: double
Local variables:
agent — the agent
Agent unit — the resource unit

'Wrap-up' preemption policy

[Visible, if Return home: custom] Specifies the policy of the “return home” task for the resource unit.

No preemption — “return home” task cannot be preempted.
Terminate — “return home” task may be preempted and will be terminated.

Local variables:
agent — the agent
Agent unit — the resource unit

Customize resource choice

[Visible if Use resources to move is selected]
If the option is selected, you can choose some specific resource unit to perform the “store agent in a pallet rack cell” operation (using the Resource choice condition below.)

Syntax: boolean customizeResourceChoice
Default value: false

Resource choice condition

[Visible if Customize resource choice is selected]
Resource choice condition — The Boolean expression that is checked to find the specific resource unit(s) that can perform the operation. If no currently available resource units matches the specified condition (the condition returns false), RackStore will wait for the first resource unit that matches the condition.
For example, an agent can be assigned a helper resource unit that is stored in the myAssistant field within that agent. We need a particular resource unit, worker, to always be assigned to this specific agent. So in this case, the Resource choice condition is agent.myAssistant == worker.

Value type: boolean
Default value: true
Local variables:
agent — the agent
Agent unit — the resource unit
ResourcePool pool — the resource pool

Resource selection

Specifies which resource units can be selected for the given agent.

Off (chooses some matching unit) — No specific preference for the selection.
Nearest to the agent — The resource unit that is closest to the current agent.
The most preferred — The resource unit is selected by comparing resources against each other. The comparison algorithm (or its call) is placed in the field "unit1 is preferred to unit2".
Unit with top rating — The resource unit with the highest rating is selected. The rating (or the algorithm that calculates it) is specified by the user in the Unit rating field.

If Off is selected, the first unit that satisfies the Resource choice condition is selected; AnyLogic checks the idle units against the condition first, then the busy units.
In all other cases, all units are scanned, including the busy ones, which means that this block’s task may displace theirs. If this does not suit you, consider using a more specific Resource choice condition.

Default value: Off (chooses some matching unit)
Valid values:
RackStore.RESOURCE_SELECTION_SOME_UNIT
RackStore.RESOURCE_SELECTION_NEAREST
RackStore.RESOURCE_SELECTION_BASED_ON_COMPARISON
RackStore.RESOURCE_SELECTION_BASED_ON_RATING_VALUE
Local variables:
agent — the agent.
ResourcePool pool — the resource pool.

"unit1 is preferred to unit2"

[Visible if Resource selection is The most preferred]
The comparison algorithm (or its call) that is used for choosing a resource for the given agent. The algorithm compares resources to each other. It should return true if the resource unit1 has higher preference than the resource unit2 (and false otherwise, including the case of choice equality). The algorithm should provide transitiveness.

Value type: boolean
Default value: false
Local variables:
Agent unit1 — the first resource unit to be compared
Agent unit2 — the second resource unit to be compared
T agent — the current agent

Unit rating

[Visible if Resource selection is Unit with top rating]
The rating value of this unit. The rating is used to choose a unit for the given agent (the larger the higher, unit with the top rating value will be chosen).
Usually an algorithm or a function call is placed here to calculate the rating with the help of the available local variables.

Value type: double
Local variables:
agent — the agent
Agent unit — the resource unit

On enter

Code executed when the agent enters this flowchart block.

Local variable: agent — the agent

On resources arrived

[Visible if Use resources to move is selected] Code executed when the resources arrive to the agent current location.

Local variable: agent — the agent

On delay starts

[Visible if Use delay is selected] Code executed when the delay associated with putting the agent starts.

Local variables:
agent — the agent
double delayTime — the delay time
RackSystem rackSystem — the rack system
PalletRack palletRack - the pallet rack
int row — the row of the cell
int position — the position of the cell
int level — the level of the cell

On delay ends

[Visible if Use delay is selected]
Code executed when the delay associated with putting the agent ends.

Local variable: agent — the agent

On exit

Code executed when the agent exits the block.

Local variables:
agent — the agent
RackSystem rackSystem — the rack system
PalletRack palletRack - the pallet rack
int row — the row of the cell
int position — the position of the cell
int level — the level of the cell

On task suspended

[Visible if Task preemption policy is set to Wait for original resource or Seize any resource]
Code executed when agent task is suspended because of Wait for original resource and Seize any resource preemption policy, when its unit gets grabbed by another task with higher priority.

Local variables:
agent — the agent
Agent unit — the unit

On task resumed

[Visible if Task preemption policy is set to Wait for original resource or Seize any resource]
Code executed when agent resumes processing after it has been suspended because of Seize any resource and Wait for original resource preemption policy.

Local variables:
agent — the agent
Agent unit — the resource unit

On task terminated

[Visible if Task preemption policy is set to Terminate serving]
Code executed when agent loses all units obtained in this RackStore block because of Terminate serving preemption policy, when one of units in the resource set (defined in this RackStore) gets grabbed by another task with higher priority.

Local variables:
agent — the agent
Agent unit — the resource unit which has originated termination

in

The input port.

out

The output port.

How can we improve this article?

Send