Logistic network
A Logistic network (LogNet) is a series of different chests and Logistic robots all covered by one or more Roboports.
Depending on the type and configuration of the chests and area of the Robotic network the robots will transport items between these chests as a power-hungry alternative to moving items manually, by belts or Railway network.
The player character can also act as Requester chest in the Logistic network, allowing you to 'request' various items be kept at a set limit within your personal inventory. After researching Character logistic slots you can configure an amount of Items and Logistic robots will start to move the specified Items from the network to your characters inventory.
Do not mix up LogNet and Circuit network. They share a common component (smart inserter), but are otherwise disconnected and do not exchange any information.
Items
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Centre of the Robotic network in which the Robots can move and with its coverage forming the logistic network. |
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Moves items between Logistic Chests. (*) |
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Logistic Chest: Supplies the contained items to the logistic network. (**) |
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Logistic Chest: Supplies the contained items to the logistic network. (**) |
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Logistic Chest: Stores Items currently not requested. Supplies the contained items to the Logistic network. (**) |
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Logistic Chest: Will be filled by Logistic robots until the configured amount is reached. (**) |
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Smart inserter: Can be turned on/off depending on the contents of a logistic network it is located in. |
(*) At the beginning each robot can carry only 1 item. This amount can be increased by researching Logistic robot cargo.
(**) Logistic chests are also usable for a Circuit network by using wires.
Basic
To start with, just use passive provider- and requester chests! Place the passive provider chests at the output inserters of assemblies and requester chests at the input (let them request the needed items). Place a Roboport, which covers these chests with the inner area. Place some logistic bots.
The robots will begin to work.
You can now limit the number of produced item either with the Chest/Stack limitation-feature or - in the long term much better - with Smart inserters, which are configured to limit the number of available items in the logistic network.
How it works
Place some logistic bots anywhere, or in a Roboport, they will immediately begin to work.
The logistic bots try to fulfill the configured requests (requester chest) by moving items from storage- or active/passive provider chest to requester chest.
Usage
This technique is very capable for creating more and more complex items in a relatively small factory-area. Low complexity and high volume activities over longer distances (like smelting) can (and should) be left using belts.
The basic thing you need are Roboports. When you placed the port and hover it, you see a orange and a larger green area.
- The orange zone is the Logistic Network area. This is also the maximum distance for connecting two roboports.
- The green zone is the Construction area.
Blow up the logistic zone
Use more roboports to create a bigger logistic-zone! When the zones of two or more roboports touch or overlap, they are linked together to form a single network. This will show as a dotted line between the linked roboports (if they have power).
The roboports are not connected, if only the construction-zone touches.
The inner zone covered by a Robotic network is identical to that of the Logistic network. You see that also, when you build a roboport, if the Roboports are connected. All Logistic network/Chests inside the zone are connected and build the Logistic network. Imagine the logistic chests send their containments to the Roboports.
There can be many separate logistic networks. Two roboports are in the same network if you could fly from one to the other without leaving logistic network coverage. To prevent roboports from linking, you need to build them far enough away from each other so that the orange zones don't touch. If you don't link a roboport, the construction area isn't linked, too!
Bots do normally not fly from one network into another (exception: when running out of charge).
Danger of losing bots
Biters love bots! But they express their love... differently... :)
Also - pay attention to robotic networks which form some kind of U-shape (where the shortest way between two chests goes over an uncovered area): if a bot runs out of charge in this area, and cannot return fast enough to a roboport, the bot falls to the ground and will be destroyed (along with anything it was carrying).
Running out of charge can happen also, if you overuse the roboports; when the charging-queue for the bots gets too long, the bots (and their loads) get lost! A roboport can charge between 50 and 70 bots ... But this is not very efficient! Limit the number of bots or build more roboports for that case. (This behavior will eventually be reduced a bit in the future)
Currently the bot and the load just disappears, if the charge goes to zero. This behavior will be changed in future.
Advanced
Network info
A Logistic network knows the numbers of all Items stored in storage and active/passive chests and also the number of all items currently carried by Logistic robots. This information can be seen by hovering over a logistic chest:
- you see the sum of all items in storage/provider chests (The list can get very long, this will be fixed)
- currently on the way in this logistic network and
- currently requested items.
Negative numbers
For some reasons, you can see negative numbers in the network info. This is not a bug. This means, that the bots can transport more than available (Logistic robot cargo).
Active/Passive Provider chest
The provider chest is used by the logistic bots as "source".
You insert the items into this chest with an inserter; a useful case is directly inserting the output of an Assembling machine/Furnace into this chest. Use a Smart inserter to limit the number of items you put into the logistic network!
The priorities between active and passive Provider chest are equal ( see http://www.factorioforums.com/forum/viewtopic.php?f=18&t=3415 )
active provider chest
- The content of active provider chests is delivered to both requester and storage chests
- Active provider chests are immediately emptied unless the demand for that item in requester chests is already met or there is no space in a storage chest left.
passive provider chest
- The content of passive provider chests is delivered to requester chests only.
- Passive provider chests are only emptied if there is a requester chest which has an unmet demand for those items.
Requester chest
The provider chest is used by the logistic bots as "target".
You can set the needed amount of items in the Requester chest. The logistic bots try then to deliver this requests. The logistic bots take the requested items (first from provider chests, then from storage chests), until the demand us fulfilled. (The delivered items can then be placed via Inserters to the destination, e. g. an Assembling machine).
more items then requested?
The delivered number of items in the requester chest can be higher than requested. This depends from the Logistic robot cargo-bonus you have researched.
Storage chest
This chest is used by the logistic bots as both, "source" and "target". You can use the storage chest in the same way as the active/passive provider chest: deliver items to the requester chests. But that is not it's purpose.
usage as target
The storage chest is used as target, when all other targets for the provider chests are fulfilled and if there are free bots left. Then the bots move items from provider- to storage-chest.
They try to move the item to a storage chest, that already contains items of the same type. Empty storage chests are filled first. This should avoid having storage chests with different items inside.
usage as source
Storage chests have a lower priority than provider chests. The bots look for a provider chest as source, before they search in a storage chest for that item.
useful cases for the storage chest?
This has been quite long discussed (See this and thread).
As the result the provider chest has been changed to the Active Provider chest and the Passive Provider chest was introduced.
There are now no cases, where the storage chest can't be used; there is always a way to integrate them into the layout and this is especially important for deconstruction or for example at Railway network/Train stations. see here )
The possible ways and order priorities
This overview reflects also the priorities, in which order the chests are filled/emptied.
Active/Passive Provider chest => Requester chest Storage chest => Requester chest Active Provider chest => Storage chest
Requests are coming from the requester chests and storage chests.
- a requested item is first looked up in the provider chests, then in the storage chests (provider chests are emptied first)
- if robots are free and there is space left in storage chests, and there are unrequested items in active provider chests, the items are moved from active provider to a storage chest.
- if a any storage chest already contains items of different type, empty storage chests are filled first. This should avoid having storage chests with different items inside.
In other words: the storage chests are filled last, emptied last and try to store the items they already have.
Order of movement
The bots fulfill all requests with the same priority. The algorithm looks for the next free robot, then the next request in the queue and after giving orders to the robot, this request is put at the end of the queue, so that first all other requests are done.
The results are not optimal; it can happen, that the farest next bot will be requested, even if there is a much closer. Because of this, it's recommended to don't use the logistic network for long distances and/or high throughput. (For that are the Railway network much more useful.)