Belt Physics - Density
Posted: Wed May 13, 2015 1:34 pm
https://forums.factorio.com/wiki/index.ph ... ts/Physics - Wiki Page
https://www.youtube.com/watch?v=_pTsp2B ... be&t=4m39s - Youtube video with different interpretation and https://forums.factorio.com/forum/vie ... 21&p=56806 - related post regarding different interpretation
Factorio Version 0.11.22
Question - Is the throughput of material on transport belts still consistent with the results documented on the wiki page from version 0.6?
Hypothesis - The throughput for the STD, FAST and XPRESS belts remain approximately 12, 20 and 30. The throughput can be determined by multiplying density with velocity.
Test - (for density only) count the number of items that exist on a fully compressed moving belt for a given length. Note - result chests are to the right. Do not count the items from the chests to the left. errors - there is a small leak of items from both sets of inserters. Although they counter each other, the amount of leakage from each set may not be the same.
- the 2 fast belts are mostly compressed but are not fully compressed since I used direct insertion to fill them. Although not apparent, the test belt may have had some small gaps in the item count.
Results -
Straight Dynamic
STD - Test 1 = 192 items, Test 2 = 192 items - 3.2 items per tile per side
FAST - Test 1 = 160 items, Test 2 = 160 items = 2.7 items per tile per side
XPRESS - Test 1 = 160 items, Test 2 = 160 items = 2.7 items per tile per side
Curve Dynamic
STD - 129 items - 2.2 items per tile per side
FAST - 120 items - 2 items per tile per side
XPRESS - 118 items - 2.0 items per tile per side
Interpretation
Using previously determined velocities of STD = 1.875 tiles/sec, FAST = 3.75 tiles/sec and XPRESS = 5.625 tiles/sec, we get the following throughputs:
STD throughput = 3.2 items/tile x 1.875 tiles/sec = 6 items/sec (same as previous)
FAST throughput = 2.7 items/tile x 3.75 tiles/sec = 10.1 items/sec (about the same)
XPRESS throughput = 2.7 items/tile x 5.625 tiles/sec = 15.2 items/sec (about the same)
CONCLUSION - Throughputs remain the same
Further thoughts
Since we are talking about computer basics, I expect to find integers as the foundation for this information. Consider the following:
1 Tile = 32 Pixels (I use pixel loosely here but it makes the most sense)
1 Second = 60 Ticks
STD Density = 3.2 items/tile x 1 tile/32 pixels = 0.1 items/pixel or 10 pixels/item (15 pixels/item after inside curves)
FAST Density and XPRESS density = 2.7 items/tile x 1 tile/32 pixels = 0.084 or 12 pixels/item
STD Velocity = 1.875 tiles/sec x 32 pixels/1 tile x 1 second/60 ticks = 1 pixel/tick
FAST velocity = 2 pixels/tick
XPRESS velocity = 3 pixels/tick
Using these densities and velocities we get
STD throughput = 1/10 items/pixel x 1 pixel/tick = 1/10 items/tick = 6 items per second
FAST throughput = 1/12 items/pixel x 2 pixels/tick = 1/6 items/tick = 10 items per second
XPRESS throughput = 1/12 items/pixel x 3 pixels/tick = 1/4 items/tick = 15 items per second
The standing density for the STD and XPRESS belts is 1/9 items/pixel (for some reason the FAST belt's standing density is 1/10 ?? - probably for optimizing but I don't like it)
Further tests are needed to corroborate the above as well as tests for checking velocities.
https://www.youtube.com/watch?v=_pTsp2B ... be&t=4m39s - Youtube video with different interpretation and https://forums.factorio.com/forum/vie ... 21&p=56806 - related post regarding different interpretation
Factorio Version 0.11.22
Question - Is the throughput of material on transport belts still consistent with the results documented on the wiki page from version 0.6?
Hypothesis - The throughput for the STD, FAST and XPRESS belts remain approximately 12, 20 and 30. The throughput can be determined by multiplying density with velocity.
Test - (for density only) count the number of items that exist on a fully compressed moving belt for a given length. Note - result chests are to the right. Do not count the items from the chests to the left. errors - there is a small leak of items from both sets of inserters. Although they counter each other, the amount of leakage from each set may not be the same.
- the 2 fast belts are mostly compressed but are not fully compressed since I used direct insertion to fill them. Although not apparent, the test belt may have had some small gaps in the item count.
Results -
Straight Dynamic
STD - Test 1 = 192 items, Test 2 = 192 items - 3.2 items per tile per side
FAST - Test 1 = 160 items, Test 2 = 160 items = 2.7 items per tile per side
XPRESS - Test 1 = 160 items, Test 2 = 160 items = 2.7 items per tile per side
Curve Dynamic
STD - 129 items - 2.2 items per tile per side
FAST - 120 items - 2 items per tile per side
XPRESS - 118 items - 2.0 items per tile per side
Interpretation
Using previously determined velocities of STD = 1.875 tiles/sec, FAST = 3.75 tiles/sec and XPRESS = 5.625 tiles/sec, we get the following throughputs:
STD throughput = 3.2 items/tile x 1.875 tiles/sec = 6 items/sec (same as previous)
FAST throughput = 2.7 items/tile x 3.75 tiles/sec = 10.1 items/sec (about the same)
XPRESS throughput = 2.7 items/tile x 5.625 tiles/sec = 15.2 items/sec (about the same)
CONCLUSION - Throughputs remain the same
Further thoughts
Since we are talking about computer basics, I expect to find integers as the foundation for this information. Consider the following:
1 Tile = 32 Pixels (I use pixel loosely here but it makes the most sense)
1 Second = 60 Ticks
STD Density = 3.2 items/tile x 1 tile/32 pixels = 0.1 items/pixel or 10 pixels/item (15 pixels/item after inside curves)
FAST Density and XPRESS density = 2.7 items/tile x 1 tile/32 pixels = 0.084 or 12 pixels/item
STD Velocity = 1.875 tiles/sec x 32 pixels/1 tile x 1 second/60 ticks = 1 pixel/tick
FAST velocity = 2 pixels/tick
XPRESS velocity = 3 pixels/tick
Using these densities and velocities we get
STD throughput = 1/10 items/pixel x 1 pixel/tick = 1/10 items/tick = 6 items per second
FAST throughput = 1/12 items/pixel x 2 pixels/tick = 1/6 items/tick = 10 items per second
XPRESS throughput = 1/12 items/pixel x 3 pixels/tick = 1/4 items/tick = 15 items per second
The standing density for the STD and XPRESS belts is 1/9 items/pixel (for some reason the FAST belt's standing density is 1/10 ?? - probably for optimizing but I don't like it)
Further tests are needed to corroborate the above as well as tests for checking velocities.