Table of Contents

Table of Contents

Storage Object

Storage Object

Overview and Key Concepts

The Storage Object is a parent class of several objects that are used to store flow items in a two dimensional grid of storage locations, called slots. These slots are organized, first by bay, then by level, and finally by position/slot number.

The Storage Object is an abstract class, meaning you do not create instances of this specific class directly. Rather, the Storage Object is a parent class of the Rack, Floor Storage, Gravity Flow Rack, Push Back Rack, and Drive In Rack classes. Thus, when you create an instance of one of these classes, you are inherently creating an instance of a Storage Object.

The Storage Object is a Fixed Resource. However, fixed resource functionality is turned off by default. You can enable it through the Flow Panel, or merely by connecting other fixed resources to it using an 'A' connection. When fixed resource logic is enabled, the storage object receives flow items through its input ports until its maximum content value is met. When each flow item enters the rack, it executes the minimum dwell time function for that item. This function returns the minimum stay time for that flow item. The rack starts a timer for that amount of time. After the timer expires, the rack releases the flow item.

Events

For information on events, see the Event Listening page.

The Storage Object is a Fixed Resource, and uses the standard events that are common to all fixed resources. See Fixed Resources - Events for an explanation of these events.

The Storage Object has the following additional events:

Minimum Dwell Time

This event occurs when the Minimum Dwell Time field is evaluated. It is only evaluated if a storage object's Use as Fixed Resource checkbox is selected.

It has the following parameters:

Parameter Type Description
Item Object The entering item, which will be assigned a dwell time
Port int The input port number for the entering item

This event returns the minimum dwell time for the specified item.

On End Dwell Time

This event occurs when an item has reached its minimum dwell time. After this event, the storage object will release the item. It is only evaluated if the storage object's Use as Fixed Resource checkbox is selected.

It has the following parameters:

Parameter Type Description
Item Object The item that has just completed its dwell time

On Slot Assign

This event occurs when an item is assigned to a specific slot in this object, i.e. when the Storage.Item.assignedSlot property of the item is set.

It has the following parameters:

Parameter Type Description
Slot Storage.Slot The assigned slot
Item Object The assigned item

On Slot Entry

This event occurs when an item enters a specific slot. It occurs at essentially the same time as the On Entry event, however, it is executed after a slot has been assigned. The slot is therefore a parameter of the event.

It has the following parameters:

Parameter Type Description
Slot Storage.Slot The associated slot
Item Object The entering item

On Slot Exit

This event occurs when an item exits a specific slot. It occurs at essentially the same time as the On Exit event, however, it is executed specifically associated with the slot that is being exited. The slot is therefore a parameter of the event.

It has the following parameters:

Parameter Type Description
Slot Storage.Slot The associated slot
Item Object The exiting item

Slot Assignment Strategy

This event occurs when the respective Slot Assignment Strategy field is evaluated.

It has the following parameters:

Parameter Type Description
Item treenode The entering item, which will be assigned a bay or level

The execution of this field is responsible fore finding a proper slot to place the item into, and assigning the item to that slot by setting the Storage.Item.assignedSlot property.

States

The Storage Object does not implement any states. Instead, use the content graph to get statistics.

Statistics

The Storage Object uses the standard statistics that are common to all fixed resources. See Fixed Resources - Statistics for an explanation of these statistics.

Properties Panels

The Storage Object uses the following properties panels:

Properties

The Storage Object shares several properties with all fixed resources:

Additionally, the Storage Object uses the following properties:

PropertyType
AddressScheme Options
AisleID String
BayProgression Options
BayStride Number
LevelProgression Options
LevelStride Number
MarkOutbound Boolean
MinimumDwellTime Code
SlotAssignmentStrategy Code
SlotProgression Options
SlotStackingAxis1 Options
SlotStackingAxis2 Options
SlotStackingAxis3 Options
SlotStride Number
StartBay Number or String
StartLevel Number or String
StartSlot Number or String
UseAsFixedResource Boolean
Visualization Options
ZoneID Options

Dimensions Properties

The storage object also supports several properties associated with its dimensions. These properties define things like the number of bays, levels, and slots, their sizes, and padding. Here a property value can be represented as a single value if all slots/levels/bays in the object are homogeneous with respect to that property. But if there are differences across bays, levels, or slots, then the property's value becomes an array.

For example, consider the NumLevels property. If the storage object contains 10 bays, and all bays have 5 levels, then the object's NumLevels property will be the single value 5. However, if the first 5 bays have 3 levels, and the last 5 bays have 6 levels, then the NumLevels property becomes an array, with one element for each bay. In this example the NumLevels value would be [3, 3, 3, 3, 3, 6, 6, 6, 6, 6].

The NumLevels property can become at most a one-dimensional array. However, other properties (LevelSize, NumSlots, SlotSize, etc.) may be two or three dimensional arrays, depending on the heterogeneity/homogeneity of the bays, levels, or slots.

The storage object also supports a Dimensions property. This encompasses all of the other dimension-focused properties, aggregated into a Map.

The dimension-focused properties are as follows

Property
BaySize
Dimensions
LevelSize
NumBays
NumLevels
NumSlots
SlotPaddingBack
SlotPaddingBottom
SlotPaddingFront
SlotPaddingLeft
SlotPaddingRight
SlotPaddingTop
SlotSize
SlotsPerBay
StorableSlots