|Description||A pneumatic tube system built from non-perforated (airtight) drainage pipe and vacuum cleaners. Being an Open Artwork, Seidenstrasse is a revision of the OCTO installation by the artist group Telekommunisten (http://telekommunisten.net/octo/, 2013). New features are: A decentralized mesh-style, push-preferred network with endpoints (no vacuum cleaners) and nodes (push-forward / pull on request). A new feature is the option to have onion routing to allow for anonymous transportation in the network.|
|Persons working on||Baruch, Bongo, Gonium, Hax404, Ker, Larsm, Mey, Spky, Tec, Wonko|
Seidenstraße ist ein Rohrpostsystem aus Drainagerohren und Staubsaugern, basierend auf der Installation OCTO der Künstlergruppe Telekommunisten (http://telekommunisten.net/octo/, 2013).
A pneumatic tube system built from non-perforated (airtight) drainage pipe and vacuum cleaners. Being an Open Artwork, Seidenstrasse is a revision of the OCTO installation by the artist group Telekommunisten (http://telekommunisten.net/octo/, 2013). New features are: A decentralized mesh-style, push-preferred network with endpoints (no vacuum cleaners) and nodes (push-forward / pull on request). A new feature is the option to have onion routing to allow for anonymous transportation in the network.
- IRC channel: #seidenstrasse on the hackint network
- Mailing List: http://lists.chaos-inkl.de/cgi-bin/mailman/listinfo/seidenstrasse
- 1 Basic Architecture:
- 2 Example network graph with adress scheme illustration
- 3 How to make your own capsule
- 4 Experimental Results
- 5 TODO
There are two types of nodes: switching nodes and endpoints.
Switching nodes are points where multiple pipes arrive and where people feel like performing the switching / routing functions. The switching nodes are preferably located at places where there are people around, such as POC, NOC, Assemblies, Heaven etc. If the switching nodes are using vacuum cleaners, noise is an important consideration. The node might be placed outside the door or so, to limit noise exposure. Todo: find out if we can use compressors or central vacuum cleaner units that can be placed in noise isolated rooms, at least for some nodes like the info-desk. (e.g. http://www.ebay.de/itm/Zentralstaubsauger-1-9-Schalldampfer-Filter-Beutel/281192395771)
Endpoints can be at any place in the building. What you need to be an endpoint: Just register at the nearest node to get your individual adress and lay a pipe between you and the node. Make sure the tube doesn't bend too much, so that your post will not get stuck. Put a padded laundry basket or similar at the tube end to collect the incoming capsules.
Each endpoint is adressed by its switching node designation plus its pipe number. Each switching node handles its pipe numbering as it sees fit. Re-numbering is strongly discouraged, if pipes fail or are shut down, just leave its number dormant.
Endstation naming convention:
The basic adressing scheme consists of the Switch Node Number followed by a : and the Endpoint Pipe Number at this node. e.g. 23: 42 (meaning: switching node No. 23, Endpoint No. 42). A barcode representation of the basic adressing scheme should be developed. Additionally, memorable naming is allowed, at least if the switching node is operated by humans. The adress then contains the name of the switching node, followed by the endpoint pipe, e.g. POC:5. Switching nodes are designated by their number or name with a following zero, e.g. POC:0
Example network graph with adress scheme illustration
X - switching node O - endpoint
[POC:0] [NOC] [8:1] [ 8:0 ] [6:0] [6:1] O–-–––––––––––––X–––––––––––––––––X–––––––––––––––O | | | O [6:2] / / | | [Hackcenter] [Heaven]X––––––X [ 4:0 ] [3:0] /| / | / | / | / | O O [4:1] [4:2]
Basic sending options (to be implemented at 30C3):
First, write the receiving address on the capsule (optional: return address) Then either a) bring the capsule to the nearest switching node to send it b) borrow a vacuum cleaner and push the capsule to the next node (may cause collisions). c) call your switching node on the DECT / VoIP or via the inband audio communication (talk through the tube) and convince them to pull the capsule by vacuuming your endpoint pipe where you placed the capsule.
Future sending options (to be implemented at 31C3 / next camp):
Automated switching nodes pull (suck) on each endpoint pipe in sequential order and keep vacuuming if there is resistance (from a capsule being in the pipe). If there is no resistance (measurably due to lower power consumption), it goes on to vacuum the next pipe round robin.
Advanced routing options:
How to send a capsule with onion routing Look up the route to the receiving address in the routing file. Write down the nodes on masking tape. Attach the masking tape layerwise onto the capsule, starting with the receiving address, then the last node, and so on. Make sure to have at least 3 nodes between you and the recipient. How to forward a capsule with onion routing: Peel off the first layer of the masking tape and forward the capsule to the address stated.
Preliminary network graph for CCH
What you need to be a switching node:
Preparation: Bring a vacuum cleaner with blower function (see list below). Bring a connector that fits the blower nozzle and the pipe (see 3D model below). Bring some laundry baskets or similar for the incoming capsules. Optional: Buy some drainage pipe and make test runs. Make your own capsules (see dimensions below). All capsules must have lighting!
At the Congress:
Lay pipes between you and the nearest nodes. Make sure that the tube is mounted correctly, and does not make any sharp bends. Note that the tube is not very sturdy. Think of ways to distribute the forces at fixing points over a wider surface area, like with a piece of cloth, a pipe with larger diameter, gaffa-tape constructions or similar. Just hanging the tube on one round of string will deform it within a day. Update the routing file with your name and the connections leading to you. When you receive a capsule, look up the address in the routing file and push (blow) the capsule to the next node in the route (or the endpoint, in case there is a direct connection). When a new endpoint registers, make sure to update the routing file. Optional: Connect the vacuuming nozzle to 'pull' capsules sent from the endpoints at regular intervals. In order to ensure reliable deliveries, a node should be (wo)manned permanently.
How to make your own capsule
Everyone who wants to participate should build their own capsules. Please post your pictures, drawings, instructions and experiences here as inspiration for others.
Important: Capsules without light will not be allowed in the system! Attach at least one LED to each capsule, so stuck capsules are visible. No exceptions!
Tube dimensions (verified by measurement): Outside diameter: 100 mm Inside diameter (the tube is corrugated): 90-92mm
Capsule properties (verified by experiment):
|Diameter||75mm||90mm||85mm||also depends on capsule's sides, if soft, thicker may be better|
|Length||100mm||220mm||180mm||too short might cause it to turn and get stuck, too long will not get around corners. (rounded and narrowed ends can be longer)|
|Weight||-10t||550g||250g||large weights need to be tested more on long tubes going up|
The ends of the capsule should be round or narrowed, so it can easily glide around bends. Take a look at how commercial capsules look like for inspiration: http://commons.wikimedia.org/wiki/File:Rohrpostbuechse.jpg
A capsule made by cutting a ring out of a 85mm 1.5l PET water bottle and putting the ends back together worked really well in experiments (see picture below).
At the largest diameter a ring of felt or the soft side of velcro should be applied to ease the gliding through the pipes and provide a better airtight seal between tube wall and capsule.
Capsule Ideas: Multicolor glowing capsules, capsules with e-paper displays, encrypted capsules (with puzzles or locks). A very good test capsule is a 500ml can of beer. It also has a 500g payload, good for testing inclines. Make sure you have something soft at the end to catch the beer, or else the can is likely to be damaged, requiring cleanup operations.
Suitable vacuum cleaners ("ShopVac" with Blower function) http://www.karcher.com/int/Products/Home__Garden/Vacuums/Wet_and_dry_vacuum_cleaners/16296000.htm http://www.shop-vac.eu/shop-vac-super-1300-inox_pid49.html?products_id=49&language=en
if you need to extend the tubes longer than 50m, you will need something like this http://www.bausep.de/Keller/Entwaesserung/Drainage/Opti-Drain-System/Verbindungsmuffe-Zubehoerteil-fuer-allgemeine-Draentechnik.html?variante=DN-100 I think this page features the standard tube we used at transmediale: http://www.bausep.de/Keller/Entwaesserung/Drainage/Drainageschlauch/Drainageschlauch-ungelocht-DN-100-gelb-50-m-Rolle.html
IMPORTANT "Halterungen" stable rings (rainwater gutter, a piece of fabric,…) to ensure the transport tubes stay round. Deckenpanele in den Foyers halten pro Panel 5 kg, bzw. 2 x 2.5kg Note that the tube is not very sturdy. Think of ways to distribute the forces at fixing points over a wider surface area, like with a piece of cloth, a pipe with larger diameter, gaffa-tape constructions or similar. Just hanging the tube on one round of string will deform it within a day.
We did some experiments at Raumfahrtagentur in Berlin. The main results are:
1. Fire safety
We tried to burn the tube and it turned out to be burn retardant. Test with a lighter revealed that the flame extinguishes itself when you remove the flame. This means that we can have connections between fire zones over the balconies and can route around the fire doors.
We tested two connected 10m pipe segments 3 floors high with more than one segment (10m) going directly up vertically. Our capsules traveled problem free through this test pipe.
3. Capsule construction and dimensions
A cylindrical capsule made from poster tube (180mm x 85mm) worked ok. Longer cylindrical capsules had problems on tight bends. Capsules made from 85mm PET bottles worked really well, as they have round edges / the narrow part of the bottle to guide it around bends.
Lighting the capsules is not an option but mandatory, as this really helps locating stuck capsules and watching performance and behaviour in the tube. Always have at least one bright LED on every capsule.
The vacuum cleaner is really noisy. We will evaluate other options like industrial blow / vacuum systems.
6. Connection to the tube
The connection to the tube is solved. We improvised something with a PET bottle and Gaffa, but that was not suitable for heavy use. A proper solution: We bought some rainpipe connectors and adaptors for Raumfahrtagentur, and sawed off a bit of the vacuum cleaner pipe. Items are called: "DN 110 / DN 50 45˚ Abzweigung", "Reduktion DN 50 DN 40", "Übergang Drän auf KG DN 100", "Drainagerohr-Verschlußstopfen".
Test run at Raumfahrtagentur: https://vimeo.com/79443700
- Get positive answers from potential nodes e.g. POC, NOC, Engel, …
- plan routes
- Publish a 3D model for a nozzle connector
- Make (longer-term) mounting tests because of known deformation problem
- solve noise problem (try out an electric leave-blower on a low setting)
- make capsule counters for network traffic analysis
- Find a text-only solution for the routing file (ASCII art?)
- make test runs
- (Raumfahrtagentur has ordered a vacuum cleaner and some tube) --> See above, Experimental results.
- entropia has tube + push vaccum cleaner
- get building plans from CCH which include *emergency fire doors* etc.
- find out about fire safety regulations at CCH e.g. *emergency fire doors* etc.
- Make a preliminary routing file
Camera in capsule: http://vimeo.com/58703548
Emergency fire doors
Experimental verification suggests that the tube is flame retardant. This means that we can route around the fire doors over the balconies.
(This paragraph needs to be verified by someone with good knowledge about this matter.)
For the non german natives, "Brandschutztüren" or emergency fire doors are doors that are <strike>normally open</strike> (see below) and must be able to close in case of a fire (to prevent spreading fire and smoke to other parts of the building.) These doors may never be blocked, assume that any CCH people will be rather anal about this, with good reason. This means no Seidenstrasse pipes can go through one of those doors.
Door types: some remain open until a fire alarm signal is triggered and some (the simple ones) are always retained in closed position by a door closer.
Now, there are multiple questions about this:
- where in the CCH are doors like this, how frequent are they?
- are there ways to pass pipes through some other hole next to the door?
- NB: along with one of the doors, there is usually a fire protective wall (the building is divided in 'Brandschutzabschnitte' / fire zones) which isn't allowed to have holes either. But maybe they have plugs that can be removed.
- Yes and no. In my experience most of the fixed cable ducts going trough a fire wall are filled with a fire resistant foam/material. If there is a hole big enough for this application i think it will be behind another fire proof door (back to start). Maybe they have special cable passings at CCH and regulations but stuff like this has to be discussed with the fire fighters in charge (at some events there are some) and/or the building/security manager. (This is my experience from helping/organizing at mid sized festivals.) I think it might be easier to run the system independently in the fore zones and have passing stations where volunteers or people passing by can transfer them.
- if nothing else, (wo)manned (or un(wo)manned, if you can build one) relay stations at these doors may be needed. Ideas?
Emergency fire door traversal by robot
Chaos inKL. is currently experimenting with a simple line-following robot that can semi-automatically transport a capsule through the fire door.
Our plan is to convert this little machine into a simple line-following robot. It loads a capsule at the start and follows a line through the fire door. At the destination it delivers the capsule and returns to the start. It will also be outfitted with LEDs and a buzzer for better visibility and interruption-free operation.