Many automated station builders have run into the same problem. Tradeback devices don't work when your other station is beyond the chunk loading distance. In this thread I offer a solution. My design is based on the two way self-resetting booster design.
Instead of waiting until you reach your destination before sending a cart back to the departure station, multiple tradeback devices along the route send carts short distances from one tradeback device to the previous one. Every time a player rides a cart from station A to station B, a series of tradeback carts shifts such that one cart is taken from station B and one cart is given to station A.
The downside is that this mechanism is rather iron-intensive. This tradeback system more than doubles the iron needed for a simple long distance system with no tradeback device.
The reason to use this system over a non-tradeback system is ease of maintenance. Players don't need to bring their own minecarts with them nor do they need to worry about minecarts piling up at one station while another station is empty. The whole point of an automated system is ease of use. The Long Distance Tradeback Device brings the ease of use of a tradeback system to long distance minecart lines.
Below is a video demonstration and a link to download my test world.
Cool idea. Though, if I were to implement this I would put the tradeback stations much further apart. If I were to guess, I would do like half the distance at which chunks begin to unload. How well does this system handle multiple passengers, or people that rapidly follow each other down the railway?
Cool idea. Though, if I were to implement this I would put the tradeback stations much further apart. If I were to guess, I would do like half the distance at which chunks begin to unload. How well does this system handle multiple passengers, or people that rapidly follow each other down the railway?
The distance I have them apart is pretty close to the maximum as far as I can tell from what testing I've done. You're moving away from the empty cart at twice maximum velocity. By the time you get to the next tradeback device (and the empty cart gets to the previous device) it will be 20 chunks away from you. But that's not to say that it couldn't be optimized. You could probably have tradeback devices slightly farther apart than in this model.
In order to account for rapid succession of passengers departing one station, you would need additional empty slots. In my video I mention keeping the system one cart below capacity. The capacities of cart magazines at each station and the number of empty slots in the system depend on the number of tradeback devices, distance between devices, and number of expected users continuously departing one station. If I really wanted to exercise my mathematical abilities, I could write a differential equation that takes all that into account, but for that I would need a standardized, preferably optimized tradeback device. The span between each tradeback device would also need to be uniform, for simplicity.
Simply put, if you have empty slots in the system, users can depart about 15 seconds apart. Only every other user-occupied cart, in that case will trigger the tradeback devices. Alternatively, you can run a tighter system with fewer empty slots and have users depart about 30 seconds apart. For ridiculously long lines, the main cart might actually need the tradeback devices to provide additional boost. In that case, you would need to allow enough time for the second tradeback cart to leave the second tradeback device before the second occupied cart can leave the station. The second tradeback cart needs to get to the first tradeback device before the second occupied cart passes the first tradeback device.
This is all hypothetical at this point, because I have not tested it on a multiplayer server.
A more user-friendly system would have a timer built into the departure platform, rendering the pressure plate useless for a period of about 24 seconds after a cart leaves. The additional time is made up by the delay inherent in the station.
Also, a note to anyone who downloads my test world: All devices are presented as-is. They each demonstrate an advancement in Minecraft engineering. They are not optimized for up-time, ease of use, use of materials, ease of building, aesthetics, or any other desirable quality. They each worked several times for me. That is enough to demonstrate a concept, which is my only aim in this save. I present these advancements mostly for the benefit of fellow Minecraft engineers and tinkerers, that they may incorporate these ideas in their own creations.
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Interesting. Well, I think this is a step in the right direction towards solving the problems with cart magazines needing to be monitored on multiplayer servers. I think the next step would probably involve doing something similar, but in such a way as it isn't as iron intensive and can be more accommodating towards possibly heavily trafficked multiplayer stations. Brilliant solution, I must say.
Instead of waiting until you reach your destination before sending a cart back to the departure station, multiple tradeback devices along the route send carts short distances from one tradeback device to the previous one. Every time a player rides a cart from station A to station B, a series of tradeback carts shifts such that one cart is taken from station B and one cart is given to station A.
The downside is that this mechanism is rather iron-intensive. This tradeback system more than doubles the iron needed for a simple long distance system with no tradeback device.
The reason to use this system over a non-tradeback system is ease of maintenance. Players don't need to bring their own minecarts with them nor do they need to worry about minecarts piling up at one station while another station is empty. The whole point of an automated system is ease of use. The Long Distance Tradeback Device brings the ease of use of a tradeback system to long distance minecart lines.
Below is a video demonstration and a link to download my test world.
Download this world!
The distance I have them apart is pretty close to the maximum as far as I can tell from what testing I've done. You're moving away from the empty cart at twice maximum velocity. By the time you get to the next tradeback device (and the empty cart gets to the previous device) it will be 20 chunks away from you. But that's not to say that it couldn't be optimized. You could probably have tradeback devices slightly farther apart than in this model.
In order to account for rapid succession of passengers departing one station, you would need additional empty slots. In my video I mention keeping the system one cart below capacity. The capacities of cart magazines at each station and the number of empty slots in the system depend on the number of tradeback devices, distance between devices, and number of expected users continuously departing one station. If I really wanted to exercise my mathematical abilities, I could write a differential equation that takes all that into account, but for that I would need a standardized, preferably optimized tradeback device. The span between each tradeback device would also need to be uniform, for simplicity.
Simply put, if you have empty slots in the system, users can depart about 15 seconds apart. Only every other user-occupied cart, in that case will trigger the tradeback devices. Alternatively, you can run a tighter system with fewer empty slots and have users depart about 30 seconds apart. For ridiculously long lines, the main cart might actually need the tradeback devices to provide additional boost. In that case, you would need to allow enough time for the second tradeback cart to leave the second tradeback device before the second occupied cart can leave the station. The second tradeback cart needs to get to the first tradeback device before the second occupied cart passes the first tradeback device.
This is all hypothetical at this point, because I have not tested it on a multiplayer server.
A more user-friendly system would have a timer built into the departure platform, rendering the pressure plate useless for a period of about 24 seconds after a cart leaves. The additional time is made up by the delay inherent in the station.
Also, a note to anyone who downloads my test world: All devices are presented as-is. They each demonstrate an advancement in Minecraft engineering. They are not optimized for up-time, ease of use, use of materials, ease of building, aesthetics, or any other desirable quality. They each worked several times for me. That is enough to demonstrate a concept, which is my only aim in this save. I present these advancements mostly for the benefit of fellow Minecraft engineers and tinkerers, that they may incorporate these ideas in their own creations.