Page 229 - ExtendSim User Guide
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Processing 203
Transportation and material handling
• Use speed and distance directly. Specifies a ratio of 1 pixel to 1 meter.
• Use 3D distance ratio. Uses the distance ratio defined in the Run > Simulation Setup > 3D tab; the default is 20 pixels per meter.
• Usedistanceratioof:Thisisforenteringtheratiodirectly.Avalueof“x”meansaratioof “x” pixels to “x” meters or feet.
☞ These options are explained more in the comprehensive example discussed in “How the length is calculated” on page 204.
Convey Item blocks
The Convey Item block (Item library) moves items along a conveyor, oven, cooling unit, moving walkway, or any other type of moving path. The items travel along the length of the conveyor, from its start to its end. The Behavior tab is simi- lar to that for a Transport block, discussed above. The differences are:
• The Convey Item block can be:
Convey Item block: Behavior tab
• Accumulating. If the block’s ability to pass items through exceeds downstream demand, any items delayed from exiting will begin piling up at the outflow end of the block, up to the Capacity setting.
• Non-accumulating. If downstream demand exceeds the block’s ability to pass items through, the conveyor will stop until the item at the end moves into the next block.
• InsteadoftheTransportblock’sreferencetothedistancefromonepointtoanother,the Convey Item block is concerned with its length.
• IfTraveltime:movetimeisselected,alengthentryisalsorequired.Incombinationwith the item length (discussed below), the conveyor’s length determines how quickly items can move onto the conveyor.
• Thelengthoftheitemsthatpassthroughthisblockmustbedefined.Theycanbedefinedas:
• Aconstant
• From an attribute
• Based on length and capacity. (For instance, if the conveyor’s capacity is 1,000 units and its length is 50 units, the length of each item will be 50/1000, or 0.05 units.)
Item length does not visually change the item picture or object but it is included in calcula- tions for accumulation, capacity, and the timing of when items are pulled onto and released from the block.
Discrete Event

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