SLGI Technology

The SLGI Trains and the SLGI Fleet are automated scheduled, while SLGI Taxis are roaming vehicles that use an unique technology.

## Overall

SLGI vehicles are automated convertable vehicles. There are two different types: SLGI Fleet (Nautilus, Corsica, Satori, Jeogeot, Gaeta 1, Gaeta 5 and Zindra) and SLGI Trains (Heterocera and Sansara).

### SLGI Trains

The SLGI Trains operate on Heterocera and Sansara.

They behave like trains on the railway and like plnens when the line ends. They are part of a project developed by SLGI team, to connect remote places and to offer touristic guides to visitors. They all depart at *House Of Freedom 1 - Achemon (22, 242, 80)*, Heterocera continent and move to a specific location. Unlike other automated vehicles the SLGI trains are rare (one at each 6 hours for each destination) and they follow a schedule. There are currently 12 destinations, each one with its own train. For a part of the distance, SLGI trains follow a common way, so they can be found more often near Achemon (at maximum one train every hour).

### SLGI Fleet

In past, they were copies of well known spaceships. Currently, they are built with the same model. They fly along the roads, waterways or high in the air, above Nautilus, Satori, Corsica, Jeogeot, Gaeta 1, Sharp Continent, Gaeta 5 and Zindra. They are part of an undergoing project developed by SLGI team, to connect remote places and to offer touristic guides to visitors. They were part of Nautilus Strait Project, later transformed in Project Atlantropa. For Nautilus, Corsica, Gaeta 5 and Satori, they depart from *SL Geography Institute - Valarian (182, 10, 200)*. For Jeogeot, they use *SLGI South - Mooter (139, 126, 95)*. For Sharp Continent, the base is *SLGI Sc - Derby (9, 88, 26)*. For Gaeta 1, the base is *SLGI G1 - Nebelung (131, 28, 27)*. For Zindra, the base is *SLGI Z - Distrel (171, 72, 21)*. Unlike other automated vehicles the SLGI spacecrafts are rare (one at each 6 hours for each destination) and they follow a schedule.

### SLGI Taxis

They are released from *House Of Freedom* and roam on Heterocera and Sansara. They are at the limit between automated and roaming vehicles. They are usually designed as chairs and are small. For them, the entire road and waterway network of Heterocera and Sansara has been divided into many small sectors connected through junctions. At each junction, they have the ability to chose on their own which sector they will travel next, at random, until, by chance, they will find the way back.

### Bases

* **SLGI West** - *Achemon (43, 236, 79)*, known as House Of Freedom, is used by the SLGI Trains and serves Heterocera and Sansara.
* **SLGI East** - *Valarian (182, 10, 200)*, serves Corsica, Nautilus, Satori and Gaeta 5.
* **SLGI South** - *Mooter (139, 126, 95)*, serves Jeogeot.
* **SLGI Sc** - *Derby (9, 88, 26)*, serves Sharp Continent.
* **SLGI G1** - *Nebelung (131, 28, 27)*, serves Gaeta 1.
* **SLGI Z** - *Distrel (171, 72, 21)*, serves Zindra.

There is no service on Bellisseria or the Premium Continents, as land there does not allow objects entry and a route can only be designed for a very short distance.

## Reason

Some residents wanted that scheduled trains to exist and move after a program, like trains on real railways. Also, some residents wanted connections to exist somehow between main railway network in Heterocera and remote rails in Sansara. And also, in East continents, people long wanted for an automated transport system to connect Corsica and Satori via Nautilus.

On the other hand, we all know the problems made by a high number of roaming vehicles on roads and railways. Creating a timetable for scheduled vehicles is a real hard job, to find the perfect solution between those who want more vehicles and those who want less vehicles (or want the railways, roads and waterways only for themselves). There are endless discussions on the forums about this subject. These vehicles are moving on Protected Land or on private-owned land (with permission). Our little team is opened for suggestions and wish the best for everybody. Roads, railways and other protected ways don't belong to a single person or a single transport company, but to all residents. Like in real world, vehicles must exist and protected ways (roads, railways, waterways and airlines) are made for transportation, however abusing of protected routes is not a good thing and must be avoided.

Other reasons were to stimulate other people's creativity and to show that Automated Transportation vehicles can be built by anybody and to show, from above, the beauty of our virtual world.

Operating these virtual trains is an honor for us and we treat it with big responsibility.

**IMPORTANT: These vehicles are NOT created for the pleasure of creating, but for the desire to make our world a better place. If you want to add, remove or modify these trains or even all trains, contact User:Ana Imfinity.**

## History

From the first days when the railway system in Heterocera was starting to take shape, people wanted a transportation service to exist. Many residents have tried this. Some of them ended in the wrong way (with punishment like a 3 days suspention), while the large majority of builders ceased their projects by their own will. In 2013, the Yava Script Pods were operating on parts of the railway (mainly in East), while Second Life Transport Authority had its cars roaming on all railway system. Roaming trains were also present.

From 2012, **World Explorer Railways Center** was almost finished in Achemon sim, but incidents from rl forced its owner to stop the project. It remained unfinished until January 2014, when it was incorporated in Achemon Railway. The purpose of World Explorer was to offer guided tours throughout the rail system of the atoll. In December 2013, SLGI (or Second Life Geography Institute) was formed, as an inworld place for Geographic articles and research. Then, after creation of Achemon Railway, the old transportation project was passed to the institute.

The first scheduled train was moving on route Achemon - Tuliptree, every 3 hours (January 2014) and the first flying train moved from Cecropia to Adelais (February 2014). Since then, new trains were inserted and schedules were changed often. First trains were not always returning home, so their scripts had to be improved many times. From all projects made by *Second Life Geography* team, this one was and is the hardest one.

Ana Imfinity and Aziv Aslan, creators of SLGI trains, are both of Circassian (North Caucasian) origin. This is the first project in Second Life developed by North Caucasian people.

The launch of SLGI Fleet started in December 2014, but for personal reasons, both Ana Imfinity and Aziv - Aslan had to put the project on a long halt. Project will be finished in June and July 2015.

In January 2016, because of the embargo after the war in Ukraine and the unrest in Northern Caucasus, Ana Imfinity was unable to login and to manage her account properly. As a result, she lost her land holdings and the project came to a halt. Beginning in July 2016, as she was able again to login, she managed to pay the tier from her online shop, but is still unable to use credit cards. So, SLGI land is now limited to two small parcels, for safety.

As for 2020, the system is finished, functional and with all vehicles released into service.

The SLGI taxis have been added in 2023 and are still being researched.

## Design

Unfortunately, there is a bug that sometimes makes vehicles not known to the system vanish or be auto-returned. Because of this reason, SLGI team decided to restrict models to only two designs, which are low-lag and are more safe to sim crossings.

### SLGI Trains

At this moment, we have one train model working on all lines: a modified version of the GSLR trolley (available anywhere as an opensource model). It has been modified by a good friend of us, who reduced prim count and painted it green. To make flying more realistic, wings have been added. We had also a modified version of the VRC opensource train, but we no longer use it. Initial trains had an extreme glowing effect and not a nice design. The trolley is more simple, low prim, low lag and complains well with space and prim restrictions found in some places.

Other types of trains had been released over time. For the moment, we will only use the modified GSLR trolley.

### SLGI Fleet

In past, all SLGI spaceships were replicas of historical space missions. Their design was simplified in order to keep lag low. Each spacecraft was small, in order to avoid any traffic problems and to keep lag low.

Currently, the SLGI fleet only uses one vehicle, a green shuttle.

### SLGI Taxis

Currently, the taxis are designed as small chairs.

### Make your own SLGI vehicle!

Second Life Geography team wanted to make a contest for vehicle builders. For financial reasons, this is not possible (except as an act of charity with symbolic prizes). If you wish your vehicle to be used, this is possible with the following conditions:

GENERAL FEATURES

1. Vehicles must not have more than 20 prims (to avoid problems with lag).
2. All vehicles must be copy-modify (can be no-transfer). This is essential to upload scripts, notecards and set features needed for each route.
3. All vehicles must make no noise and no smoke (although little smoke can be ok).
4. All vehicles must have certain rotations (at zero rotation, they must point East).
5. Dominant colour must be green. This does not mean that they must be entirely green or have a specific type of green.
6. No lights, no glowing parts, no special effects.
7. No complicated textures or hard to rezz scripted prims (this can affect lag). No excessive transparent features.
8. Unconventional models are appreciated.

SLGI TRAINS

1. All trains must have wings or space to add wings (the wings are visible only while flying).
2. All trains must not be longer then a trolley (to avoid entering nearby parcels in tight spaces) and not too wide.
3. Trains must work well with the opensource train script (this affects the angles).

SLGI FLEET

1. All spaceships must not be bigger than a car (to avoid entering nearby parcels while flying through narrow spaces).
2. All spaceships must allow avatars to sit properly.

SLGI TAXIS

1. All taxis must be about the size of a chair.

IMPORTANT: All vehicles must be green. Models with other colour will not be accepted by default. It is, however, not required to be glowing or to have a specific type of green (or to be completely green).

## SLGI Technology

All SLGI vehicles are nuclear powered. They have two engines (two scripts, used for different movements).

### Nuclearpunk

According to the legend, these vehicles use Soviet plutonium that was extracted from the ruins of Urban Degenerate's Chernobyl site in Calleta and later from their abandoned land holdings in Obscure. Also, plutonium can be found at the radioactive Plusia station, from time travelers that come from the cold war era.

Another legend says that these vehicles are a hazard to the environment and caused many trees to dry-up along the railway. Also, when a train crashed in the Gulf Of Lauren, close to Bay City, radiation from its leaking reactor caused some fish to suffer mutations and transform into dragons and fireflies.

Aziv - Aslan guaranteed that radiation level is set *only twice above lethal dose*, but despite this, SLGI team insists that riding these trains and ships is not dangerous, but only lethal for passengers.

### Train engine

The train engine is similar to a steam engine, only that instead of burning coal it uses energy from plutonium decay. Since this process generates far more heat, it allows us to produce a highly efficient type of engine, with steam reaching over 1000 degrees.

This engine was created in time after severe successive modifications of the classic VRC train engine. The current version is highly efficient and precise for high-detail movement, but slower then the standard

Currently, the train engine is used at sim crossings and at along narrow strips of land, where vehicles must squeeze with high precision.

### Plane & spacecraft engine

The plane engine is a modified version of a Fission Engine. This kind of locomotion was proposed by the Orion Project to push a spacecraft to the nearby stars. Small amounts of plutonium are exploding in every second, creating the needed thrust to push the vehicle forward. Every second, each vehicle creates 17 explosions. At a close examination, one can see that SLGI vehicles don't move in a smooth line and can see how vehicles are pushed by endless bursts. This kind of propulsion can generate more speed and is highly efficient. It is used almost anywhere, except for sim crossings or when a ship passes through narrow parcels.

Many thanks to **Aziv - Aslan** who suggested this kind of locomotion and helped to create it.

### Multiple stage rocket

As vehicles move forward, they tend to exhaust their fuel. This is just as rockets exhaust their own fuel and in order to send a spaceship to another planet you need to use a multiple-stage rocket. Once the first stage has finished its fuel, the next stage starts working. In the same way, SLGI vehicles, at some point, stop and detach used fuel. Then, they continue moving. When they return home, there is no fuel left, so that vehicles cannot start another journey.

### Taxi engine

The taxis use the same engines, but they can reuse the fuel. Each taxi has all possible routes stored in hundreds of notecards. At each junction, the taxi decides which way to go by random choice. This means that a taxi can either find its way back home within minutes or it can roam for days until a sim restart process finally destroys it.

## LSL Scripts

Now, let's talk about some real problems.

The script used by SLGI vehicles is the most low-lag of all scripts used on any vehicle. Multiple tests proved that it simply cannot affect sim performance, even if 100 vehicles are moving at the same time. Also, it is extremely efficient. Vehicles follow their paths with an error of only one meter.

### Launch mechanism

When launched, all SLGI vehicles carry only an initializing script which configures them. After they are being released, they are loaded with all they need: engine scripts (flying engine for speed, train engine for precision, safety scripts which delete the vehicle if it runs off-course and communication script which allows them to report their position to the base). All notecards needed for the route and the prim hosting them (SLGI Plutonium) are also loaded. The initializing script is destroyed after launch.

This technology allows a quick update to be installed without the need to modify the vehicles at all. It also sets vehicles so that additional scripts and notecards can be inserted while they are running. In case of emergency, as the vehicles are already initialized, a tracker can be sent fast to reach all vehicles and set them to self-destruct or change trajectory if needed.

For the taxis, the process is longer, as they need to upload hundreds of notecards with all possible routes they will encounter. Still, it does not take more than a minute.

### Engine principle

Both engines are used for non-physical vehicles. It was shown that physical vehicles are less reliable to follow their route and survive less sim crossings. The two engines use a completely different script principle. The plane engine is unique, not compatible with any other vehicle engine, while the train engine, by far, has a few common principles with the VRC opensource train engine.

### Memory and fuel change

In past, SLGI vehicles did not use notecards for memory. Data was stored inside the scripts. However, since scripts have limited memory, vehicles should use many scripts to hold all data. Many scripts will increase lag. So, the principle used was to store scripts inside a prim (named *SLGI Plutonium*), that was rezzed from time to time. After completing all data from one script, the plutonium was rezzed in a rezz zone. While the initial script was deleted, the prim sent to the vehicle a new script with instructions. The replacement of an engine script, with the rezz of SLGI Plutonium, is named a *fuel change*.

However, since 2019, we decided to make an update. Before this, train engines were searching for guides along the railway. We decided to store position of all guides in a database, to reduce lag. This proved to be too much for a script to handle, so we started using notecards for memory. Currently, the *fuel change* is only symbolical and represents the change of a notecard to the next one.

### Percent of errors

In normal conditions, measurements showed that about 90 to 98% of vehicles return home, depending on what route. Also, they keep following their schedules with an error of 5%. The most frequent problem the 'region logout process' that deletes all existing vehicles and passing through a sim and might send vehicles out of road.

To avoid problems, vehicles have a deleter. The self-destruct function is activated when:

1. a vehicle enters unwanted parcels and remains there more then 300 seconds
2. a vehicle is immobile for more then 200 seconds
3. a vehicle stays inside a sim for more then 20 minutes
4. a vehicle is over 30% late from schedule
5. emergency command is sent to them by trackers.

Since the beginning of SLGI Transport Systems, we encountered a lot of problems. Up to this date, for those 2% to 10% of vehicles that fail reaching their target or returning home, the reasons of their failure are as follows:

* Sim logout process: 40%
* Sim crossing problems: 40%
* Excessive lag in a sim: 10%
* Griefer attacks: less than 1%
* Technical problems: only to newly released vehicles.

Vehicles move from navpoint to navpoint along their routes. Depending on route, there can be up to 4000 navpoints. During a sim restart process or during massive lag events (like a griefer attack), vehicles might move shorter, further or sideways from a navpoint. To ensure safety, after one movement is completed, the vehicle checks how far it is from the navpoint. If it is more than 1 m away from target, it will attempt to teleport. If two teleporting attempts fail, the vehicle will self-destruct. This method ensures that the chances of entering nearby parcels are smaller.

## Monitoring

Unlike Second Life Transport Authority or Yava Script Pods, we don't have access to an external server. For a long time, the only way to know where these vehicles are was the use of their timetables and Heterocera railway interactive maps. These vehicles don't have contact with any external or internal server and so they are completely on their own on their schedules.

### Trackers

Main article: SLGI Trackers.

Trackers are glowing green spheres, that move extremely fast along the route, usually teleporting. They follow the route of a specified vehicle and search for it along the way. Trackers are the fastest moving vehicles existing in Second Life and can travel 20 km in two minutes (around 1000 km/h). In practice, they move slower, as they need some resources to scan for target vehicles. To avoid any problems, they fly at high altitude.

Trackers can be used to identify vehicles on the way, return and pinpoint their position on the map. Also, there is an emergency protocol, that can send trackers, to deploy deleter scripts into each train and remove them all from the grid.

Currently, trackers are used only in case of emergency, as, overall, they use more resources than the online maps.

### Online maps

Each SLGI base has an online map, showing the position of all vehicles. This is done using Object to object HTTP communication. This method generates more lag inside the sim the map is located, but can create less problems than a network of trackers. Vehicles report every 100 seconds their position to the map.

Each map displays last known position of a vehicle and the sim where the vehicle was last time.

There is some additional data that is not shown on the map: if the vehicle is running late or fast, if it is crossing a high lag area or if it is experiencing technical problems on the route.

On the maps, vehicles are usually shown as green dots, but can appear as yellow (if they have passengers), blue (if a self-destruct sequence was initiated) or red (trackers, used to measure sim crossing safety or lag).

### Memory sensors

Each base stores some data about vehicles, like the number of launched or returned vehicles, the last location from where they called home, if they had a malfunction, if they are following the schedule or if they follow the route. This data is partially available to all residents.

We carefully monitor the efficiency of these vehicles, the time spent with or without passengers, the safety of the route (and crash areas) and the effect vehicles have on the surrounding sims. No personal data is stored (no avatar names or keys, no parcel names or details). All data is stored inside Second Life, inside each SLGI base, in the green spheres located near each map.

### Lag Measurement

How much lag does a SLGI vehicle cause? Tests showed that even if 100 vehicles run altogether through the same sim, performances of the sim are not affected. The amount of resources consumed by a vehicle is about twice that of an opensource train that runs on the railways of Heterocera. The biggest resource consumer is not the engine itself, but the script used to report position to the map. Still, this happens only once every 100 seconds and it is still inworld. Nothing goes to an external server, all circles inside Second Life with an object-to-object communication method, which is at least 3 times less lag-generator than scripts which communicate outside of SL. Scripts have no listeners and communicate through editing the object's description, which is far less lag than a prim-to-prim link message.

Many of the items that we currently wear, like an animation AO or a scripted cigarette or a scripted phone with a HUD or clothes that have a HUD control for colour and resize, might actually consume more sim resources than a SLGI vehicle.

The only moment when a vehicle becomes high-lag is when it changes fuel. That lasts a few seconds. During that time, it becomes as lag as a railway switch stand. But even that is not high enough to cause trouble. If 20 vehicles change fuel in the same time and on the same parcel, the effect is still not significant to cause lag.

## Policy

On private-owned land, vehicles are moving with permission. However, since majority of private railways are group owned, it is impossible to talk with everybody. A notecard was released for the VRC group. If you are a member of a group that owns land on a railway and don't want trains to move on your land, please contact us.

It is possible that, caused of an error, these vehicles lose their way and enter nearby parcels. This happens at one in 600, in 80% of cases when a sim is behaving not normally (a bug, high lag, griefer attacks or sim logout process). More often, this is happening to experimental or new vehicles released into schedule. More often, it is possible that SLGI vehicles, while flying, enters with a part of its body (the edge of its wings) on private land. If you see any of these happening, please tell us, to correct the route.

On protected land, vehicles are allowed to move. Still, the point of view of nearby residents is important. It is important both the point of view of residents nearby the protected land and the residents moving on protected land, by foot or with other vehicles. So, if required, vehicles can become invisible in a specified area or they can fly at a higher altitude.

If residents from nearby parcels wish, vehicles might become partially invisible while passing nearby or can fly on other altitudes. And also, if you own a station or a parcel near the railway, road, water or in air and wish to, we can make vehicles to stop at your station or enter your parcel. If you wish, a complete time schedule for a specified station can be sent to you on a notecard. And also, if a group of residents wish, these vehicles will be removed from a schedule.

Since the beginning of the project, our team received many messages, 90% of them were appreciations for the project and 10% were against it.

It is almost impossible to always keep an eye on all vehicles. This is why each vehicle is equipped with a deleter, that activates when:

1. a vehicle enters unwanted parcels and remains there more than 300 seconds
2. a vehicle is immobile for more than 200 seconds
3. a vehicle stays inside a sim for more than 20 minutes
4. a vehicle is over 30% late from schedule
5. emergency command is sent to them by trackers.

However, if a vehicle gets stuck in a parcel that has *no scripts* and has *auto return* set to zero, that vehicle is unable to phone home and remains blocked there until someone removes it. We strongly apologize for this inconvenient, as there is nothing we can do about it. If you see a SLGI vehicle stuck on the way, please contact Anaimfinity.

## Schedule

To see the schedules, please go to the following addresses:

* SLGI Trains
* SLGI Fleet

## See Also

* Second Life Geography
* SLGI Transportation Systems
* List Of Railways

* SLGI Transportation Systems
* SLGI Vehicle Schedule
* SLGI Fleet
* SLGI Taxis
* SLGI Trains
* SLGI Transport Policy

* Achemon Railway
* Automated Transportation
* Roaming Continental Vehicles
* Second Life Transport Authority
* Yava Script Pods