Logistic network

This gif shows how robots can load or unload chests in a train station. The top track is for loading and there are Requester chests on both sides. The requested items are then filled into the wagons. The second track is the unloading track, the delivered items are filled into Active Provider chests and then put into the Storage chests at the very top and at the center. At the bottom the incoming ores from both sides are moved into Active Provider chests and then put into the requester chests at the top track. Logistics robots are ideal in train stations, since you need very high item throughput on a short distance.

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. Also do not mix up logistic network with construction network or combinations of the two called Robotic network.

Items

Roboport	Centre of the Robotic network in which the Robots can move and with its coverage forming the logistic network.
File:Logistic-robot.png Logistic robot	Moves items between Logistic Chests. (*)
File:Provider-chest.png Active Provider chest	Logistic Chest: Supplies the contained items to the logistic network. (**)
File:Logistic-chest-passive-provider.png Passive Provider chest	Logistic Chest: Supplies the contained items to the logistic network. (**)
File:Storage-chest.png Storage chest	Logistic Chest: Stores Items currently not requested. Supplies the contained items to the Logistic network. (**)
File:Requester-chest.png Requester chest	Logistic Chest: Will be filled by Logistic robots until the configured amount is reached. (**)
Smart inserter	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 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

Logistic network 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 or railway network.

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.

Expand 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).

If only the construction zones touch or overlap, the roboports are not connected.

The inner zone covered by a Robotic network is identical to that of the Logistic network. All Logistic network/Chests inside the zone are connected and make up the Logistic network. Items in logistic chests are available for request by the Player or another chest within the logistic network.

There can be many separate logistic networks. Two roboports are in the same network only if they are connected, as described above. To prevent roboports from linking, the Player needs to build them far enough away from each other so that the orange zones don't touch.

Bots do normally not fly from one network into another (exception: when running out of charge).

Danger of losing bots

Logistics robots are a priority target of biters, and will prioritize attacking them over many objects in the vicinity of the robots.

With v0.10.0 the bots are not longer destroyed, when running out of energy, but have then only 20% of their speed, which gives them the chance to reload and a chance for the player to find the problem.

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 will be significantly slowed and as a result the logistics network will frequently slow down at this point.

Robots may run out of charge on longer journeys. When the charging-queue for the bots gets too long, the bots (and their loads) will slow down. Generally, a roboport can charge between 50 and 70 bots, but are not very efficient at charging large queues of bots and can quickly become overworked.

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!

The logistic network numbers report items in provider and storage chests, minus the amount of items scheduled to be picked up by robots.

This means, that the bots can transport more than available because of Logistic robot cargo:

• A chest orders a robot to pick up one item to bring it to another chest.
• But the robot is able to pick up two. And will also pick up two, if available then.
• So, the simple calculation is: One item available, minus 2 items, that are ordered to picked up is -1 items.

Realistically, it means "you are trying to use more of these than you're producing" - increase production rate if you want to get rid of a bottleneck.

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 requester 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.

The logistic network looks for orders by the chests in this order:

Source	Target
File:Provider-chest.png Active Provider chest	File:Character-logistic-slots.png Character logistic slots|-	File:Storage-chest.png Storage chest	File:Character-logistic-slots.png Character logistic slots|-	File:Logistic-chest-passive-provider.png Passive Provider chest	File:Character-logistic-slots.png Character logistic slots|-	File:Provider-chest.png Active Provider chest	File:Requester-chest.png Requester chest|-	File:Storage-chest.png Storage chest	File:Requester-chest.png Requester chest|-	File:Logistic-chest-passive-provider.png Passive Provider chest	File:Requester-chest.png Requester chest|-	File:Provider-chest.png Active Provider chest	File:Storage-chest.png Storage chest|} To read this: Requests are coming from the Character logistic slots, requester- and storage chests and are accessed in this above given order. A requested item is first looked up in the active provider chests, then in the storage chests, then the passive provider. So the active provider chests are emptied first, then the storage chests, then the passive provider chests. If robots are free and there is space left in storage chests, and there are unrequested items in an active provider chests, the items are moved from active provider to a storage chest. For the storage chests, the bots search for one storage, which has the same item already filled. Only if that can't be found, they "open up" a new storage chest. This should avoid having storage chests with different items inside. In other words: the storage chests are filled, when all requests are fulfilled, emptied before using the passive provider chests and try to store only the items they already have inside. 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. In reality it looks very often like, that far chests are less frequent delivered, than near chests. This is especially true, if you order small number of items. This is explained, if you look at the "delivery" status of a requester-chest (hover over the requester chest): There are not more items delivered, than needed at a time. So if some bots already on the way to a far away chest, and the number of delivered items to this chest is equal or higher than the needed, then there will be no more orders, until that number is again smaller. What you can do is to increase the number of items you request for the far away chest, raise the number of bots in your system, or increase the number of missing items in your network. The results are not optimal; for example it still happens, that the farthest next robot will be requested, even if there is a much closer. Because of this, it's recommended to not use the logistic network for long distances and/or high throughput. (For that are the Belt transport system or Railway is much more useful.) See also Transport/What Transport for which case?, that explains, which transport system is best useable for which case. See also Robotic network Robots Transport