Page 511 - ExtendSim User Guide
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Tutorial II 485
Some things to notice
block is connected in the model. For instance, Conveyors 2A and 2B are horizontal in the 2D model but are displayed at an angle in the E3D window.
Mounting objects
You may have noticed that the item objects move in the E3D window as you would expect them to – the crates move along the conveyor and the machines process the crates as they arrive. You will see how to explicitly mount objects in the next chapter. But for this model, there was no need to explicitly cause one object to be mounted with another object
The movement of items in the Production Line model is due to two E3D features:
• Item objects automatically use the from
and to location information in the Trans-
port Animation tab of the Convey Item
block. The default is that the from loca-
tion is the previous non-passing block and the to location is the next non-passing block. This causes the item object to be displayed as moving along the path represented by the Convey Item block’s object. (The options on the Transport Animation tab will be discussed further in the next chapter.)
• BydefaulttheItemAnimationtabs
of Activity blocks are set to Mount
item while activity is ongoing.
This causes the item object (the
crate) to stay with the Activity’s object (the machine) until it has finished its processing. (As you will see in the next chapter, you may not always want that behavior.)
Moving blocks linked to objects
For the Production Line models, each of the objects in the E3D window are linked to the blocks in the 2D model. This is seen in their Block Animation tabs, where the checkbox Link 2D/3D positions is selected by default.
If the 2D and 3D positions are linked, moving most types of blocks in the model will also directly move their objects in the E3D window. However, the Convey Item block has more complex behavior. If its Block Animation tab is set to Stretch 3D object to conveyor’s length (the default setting), moving the block itself will have no effect on the position of its 3D object. That is because its displayed length is based on the starting and ending points of the conveyor in the model. If the from location is the previous non-passing block, and the to location is the next non-passing block (the default settings), the conveyor will be stretched between those two locations regardless of the position of the Convey Item block.
For example, moving Conveyor 1 between the Queue and Machine 1 will not change the loca- tion of its conveyor object in the E3D window. However, moving either the Queue or Machine 1 will result in a change in the conveyor’s position.
☞ You will not be able to see the change in position until the simulation is run.
The Convey Item block (Item library) moves items along a conveyor, oven, cooling unit, mov- ing walkway, or any other type of moving path. The items travel from the starting point to the end along the length of the conveyor.
The block has three options for setting the travel time:

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