85 replies to this topic

[blinkin]

MuKen, on 23 May 2013 - 04:40 PM, said:

[/size]

Vibrations don't propagate with consistent speed, so you can't get as accurate a distance measure from a single vector. That's why you need a greater separation of input points to achieve accuracy at the same distance using vibrations as by viewing light.

And, eye-based detection of location gets a lot worse when the air between you and the target becomes highly inconsistent too. That's why we have phenomenon like heat haze and mirages when heat warps the consistency of the air. The ground is far less consistent than even that.

But sure, if all the maps were composed of consistently dense, flat surfaces, then yeah accurate seismic detection with close points would be believable.

actually we use these methods for monitoring earth quakes currently. with 2 off set sensors (one in each foot) you could easily triangulate the location of a target that is close to you. we can already pinpoint the epicenter of an earthquake that happened on the other side of the globe to within a few miles and we can even determine how deep it was in the crust.

we use these tools to monitor mild shifts in volcanic activity for SPECIFIC mountains.

this is not only something that can be done, but it is something that we currently do IRL.

the speed of sound does vary some but in this sort of tight proximity the margin for error would likely not be more than a few millimeters.

also any seismic activity creates 2 types of waves that travel differently through materials, and can be compared to clear up any inconsistency.

i was going to go through a big long explanation of how seismic waves travel, but then i realized having two separate sensors renders that completely unnecessary. the feet are not far enough apart for any major material changes and simply comparing the two readings would be more than enough to find a specific range and location.

Edited by blinkin, 23 May 2013 - 11:45 PM.

[OneEyed Jack]

Kitane, on 23 May 2013 - 05:39 PM, said:

I can imagine a next module to be introduced. Advanced vibration dampeners to reduce seismic detection range by 50-75%.

Level 1 is Bunny Slippers, but for 15,000 more GXP you can upgrade to Bear Paw Slippers.

[MustrumRidcully]

It might simply consist of 3 seperate sensors inside your mech.
The sensors are sensitive enough to pick milli-second or nano-second of the delay between each signal they get, and a computer calculates the position.

It's all a matter of how precise the fake sensors in your fictional sensors are.

[Dreacos]

Breeze, on 23 May 2013 - 03:37 PM, said:

It's been a while since I read the books, but I believe this was brought up in the Gray Death Legion trilogy (I think?). In the third book (?) it suggests that Grayson Carle tapped into the planetary network of seismic detection computers, zoomed into his immediate area, then overlaid the local geographical mapping over that, thereby giving him a sense of movement made by the enemy.

So in other words: science fiction.

I'd say that the seismic sensor in MWO is supposed to emulate that bit of lore. Perhaps we can explain it as a module that doesn't actually read seismic activity, but it tuned to an already existing planetary network to infer information from.

Again, I'm (quite) a bit fuzzy on which exact bit of lore is accurate, and what I've said it is from memory alone.

Also keeping in mind that every map features mining bases (i.e., every capture point), It's not a big stretch to imagine these areas have some sort of stationary sensor equipment, while the module itself, acting as an anchor point, reads both vibrations from around the mech and these stationary sensor data to translate them into meaningful data for the mech's standard sensor equipment.

By the way, a mech's sensors are incredibly powerful by themselves, considering how quickly they can scan a hostile to gather information on not just weight/type but armor/internals/weapons as well, on a real-time basis to boot. Even if there weren't any stationary sensors in the area, I'm fairly certain the sensors could combine seismic data with sound (way easier to triangulate) compare this data with known location of friendlies, and show the estimated location/direction/speed of a boogie.

[Noesis]

I'm going to be a devils advocate here purely to ask the people who work in the field or know about this topic first hand as practical applications on the next point of consideration from a RL perspective. (Assuming of course it doesn't break any official secrets act with technology limitations for things like military applications).

But how would interference patterns in wave dynamics (P and S waves) from multiple Seismic sources potentially cause problems with the detection process? Or is processing power and things like tri-axial accelerometers, geophones and other similar devices simply sensitive enough to distinguish between multiple sources easily? Does the relative spread of triangulation get affected here to be able to best distinguish the input signals with some accuracy? Would clever frequency behaviour patterns/ranges be needed to help filter footfall characteristics? Of course for any kind of futuristic concerns these things could be much improved, but just have an interest really on the relative capabilities of these kind of devices in the real world today.

Otherwise Funsics works for me in a futuristic stompy robots game.

Edited by Noesis, 24 May 2013 - 05:49 AM.

[Sheraf]

If you can figure out the distance of the wave source then eliminate multiple waves coming from the same source with slight different angels can be assume to be from the same mech.

Funsics will become real world stuff if we put enough effort into it

[Noesis]

Sheraf, on 24 May 2013 - 07:23 AM, said:

If you can figure out the distance of the wave source then eliminate multiple waves coming from the same source with slight different angels can be assume to be from the same mech.

Funsics will become real world stuff if we put enough effort into it

I was thinking more to do with wave interference behaviour with multiple Mechs as opposed to the idea of pinpointing wave sources. i.e. interference noise potentially confusing some interpretation as a result of multiple enemy sources.

[Stoicblitzer]

Here's how it works.

Quote

Seismic Sensor:



- 7,500 GXP
- 200 m range
- Detects enemy Mechs as they impact the ground during movement or falling
- Enemy Mechs that move or fall within the module's range leave behind "blips" on the minimap and battlegrid
- The heavier the Mech and/or the faster its speed, the larger and faster the blip

Advanced Seismic Sensor:

- 10,000 GXP
- Automatically upgrades all Seismic Sensors
- Increases the sensors' detection range to 400 m

Why does it detect enemies only? Uhh it knows your team has 7 other people and it filters out their waves? Who gives a **** how?

[MaddMaxx]

Noesis, on 24 May 2013 - 07:41 AM, said:

I was thinking more to do with wave interference behaviour with multiple Mechs as opposed to the idea of pinpointing wave sources. i.e. interference noise potentially confusing some interpretation as a result of multiple enemy sources.

Think of a calm pond. Throw a stone out, record the distance thrown, then watch the ripples come back. You may throw many test rocks if you like.

Now, if someone else threw another stone, the same distance and all you got to see were the ripples from that stone approach, could you figure out, to a pretty close proximity, how far out that rock landed.

Same with seismic waves and or frequencies. Once some samples are collected by the system it knows that certain ripple frequency spacings equal certain distances traveled.

As to the interference, again, throw one stone then another shortly after, the waves simply pass through each other as they proceed outwards. There is likely an effect, but our mechs Seismic gear is pretty well attuned.

Edited by MaddMaxx, 24 May 2013 - 08:03 AM.

[Ngamok]

Kraven Kor, on 23 May 2013 - 02:33 PM, said:

Then how do earthworms do it?

Many subterranean creatures can sense the presence and even location of predators or prey, without the need for triangulation.

Or, that is my understanding; I could be wrong.

You know the old put your ear on the train tracks trick to hear a train coming by the vibration along the rail.

[Sheraf]

Noesis, on 24 May 2013 - 07:41 AM, said:

I was thinking more to do with wave interference behaviour with multiple Mechs as opposed to the idea of pinpointing wave sources. i.e. interference noise potentially confusing some interpretation as a result of multiple enemy sources.

If we can pick up a wave fast enough before the next wave come, that could be reduce propably, but yes you right, I can't think of a way to get rid of interference all together to give pinpoint reading.

Stoicblitzer, on 24 May 2013 - 07:46 AM, said:

Here's how it works.



Why does it detect enemies only? Uhh it knows your team has 7 other people and it filters out their waves? Who gives a **** how?

They are already on your radar, just ignore that location, unless enemy mechs able to land on top of your allied head

Edited by Sheraf, 24 May 2013 - 08:40 AM.

[Ngamok]

Soy, on 23 May 2013 - 03:24 PM, said:

HOW DOES SEISMIC WORK WHEN YOU ARE IN THE MIDDLE OF JUMP JETTING AND COMPLETELY OFF THE GROUND.

* Seismic is Lord I don't question its ultimate authority, just... just sayin...

Space Magic Sesnors. But really, are you off the ground 100% of the time? No, once you land technically, you are getting data again.

[MuKen]

blinkin, on 23 May 2013 - 11:31 PM, said:

actually we use these methods for monitoring earth quakes currently. with 2 off set sensors (one in each foot) you could easily triangulate the location of a target that is close to you. we can already pinpoint the epicenter of an earthquake that happened on the other side of the globe to within a few miles and we can even determine how deep it was in the crust.

we use these tools to monitor mild shifts in volcanic activity for SPECIFIC mountains.

Key point highlighted. I am agreeing with this. But it does not apply to using sensors that are a few meters apart to locate mechs which are hundreds of meters away with pinpoint accuracy.

Yeah we can locate earthquakes really far away within a few miles. A mech is not an earthquake, and those points on your radar don't represent "within a few miles" level precision.

Quote

i was going to go through a big long explanation of how seismic waves travel, but then i realized having two separate sensors renders that completely unnecessary. the feet are not far enough apart for any major material changes and simply comparing the two readings would be more than enough to find a specific range and location.

It's not about material changes between the two feet, it's about the material changes everywhere else. The material between the two feet is not necessarily representative of the general consistency of the material between you and the target mech. This directly impacts the usefulness of your differential measurement.

Edited by MuKen, 24 May 2013 - 09:43 AM.

[Sam Slade]

Caleb Brightmore, on 23 May 2013 - 02:14 PM, said:

Thanks for anyone who can help me with this question which may be as silly as I think the module is

Math. Computer knows where your teammates are, cross checks with seismics, marks contact as friendly... now that ECM doesn't alter friendly radar it is fine to mix them..

BUT...hostile ECM should change all seismic contacts to red or neutral(no cross check, no way to know)

[blinkin]

MuKen, on 24 May 2013 - 09:36 AM, said:

Key point highlighted. I am agreeing with this. But it does not apply to using sensors that are a few meters apart to locate mechs which are hundreds of meters away with pinpoint accuracy.

Yeah we can locate earthquakes really far away within a few miles. A mech is not an earthquake, and those points on your radar don't represent "within a few miles" level precision.



It's not about material changes between the two feet, it's about the material changes everywhere else. The material between the two feet is not necessarily representative of the general consistency of the material between you and the target mech. This directly impacts the usefulness of your differential measurement.

http://en.wikipedia....iki/Seismometer :
Ancient era




Replica of Zhang Heng's seismoscope Houfeng Didong Yi
See also: List of Chinese inventions
In AD 132, Zhang Heng of China's Han dynasty invented the first seismoscope (by the definition above), which was called Houfeng Didong Yi (literally, "instrument for measuring the seasonal winds and the movements of the Earth"). The description we have, from the History of the Later Han Dynasty, says that it was a large bronze vessel, about 2 meters in diameter; at eight points around the top were dragon's heads holding bronze balls. When there was an earthquake, one of the mouths would open and drop its ball into a bronze toad at the base, making a sound and supposedly showing the direction of the earthquake. On at least one occasion, probably at the time of a large earthquake in Gansu in AD 143, the seismoscope indicated an earthquake even though one was not felt. The available text says that inside the vessel was a central column that could move along eight tracks; this is thought to refer to a pendulum, though it is not known exactly how this was linked to a mechanism that would open only one dragon's mouth. The first ever earthquake recorded by this seismograph was supposedly somewhere in the east. Days later, a rider from the east reported this earthquake.^[6][7]

this technology is incredibly old. all you need is a direction from 2 separate sources, then you check where they intersect and there you have the exact location. the speed of the waves is entirely irrelevant.

any machine that is over 20 tons will likely make a noticeable impact tremor that even humans can detect out to several hundred meters when the feet impact the ground. the whole weight of the machine is falling to impact the ground with every step.

[MuKen]

blinkin, on 24 May 2013 - 01:49 PM, said:

this technology is incredibly old. all you need is a direction from 2 separate sources, then you check where they intersect and there you have the exact location. the speed of the waves is entirely irrelevant.

Yes with two separate sources that indicate direction you can get a pinpoint location without a distance measure. And the further apart those two sources are, the more accurate your location will be, the closer they are the less accurate, that's the point I've been making.

Say you have directional accuracy of +/- 5 degrees. You have two points that are 100m apart, and you are trying to locate a third point that is somewhere in the general area of a regular triangle (i.e. 100m away from each of them). Then you draw the intersection of their measured directions (which comes out to two cones of error), and the intersection of those two cones is pretty small, meaning that we have a pretty accurate guess of where that third point is.

Now say that those two measurement points are only 5m apart, trying to find a third point 100m away. Draw two +/- 5 degree directional cones pointing at the third point. What is the intersection? It is by comparison HUGE because the two directional cones have a lot of overlap. These two points are not able to draw a very accurate picture of where the third point is, despite having the same individual accuracy as in the first example.



This image illustrates what I'm talking about. All four sensors are looking at a point at about the same distance with the same accuracy of directional measurement. The green area shows how accurate they are with far points; they are able to tell where the third point is with pretty tight accuracy.

The red area shows how accurate they are with nearby origin points. While they know what direction the third point is in, they have relatively no idea how far away it is. They cannot get an accurate location.

Edited by MuKen, 24 May 2013 - 02:13 PM.

[Sheraf]

Anyone up for making real working seismic sensor?

[LordBraxton]

it is just Radar from

Halo Combat Evolved

who asked for this feature?

[Sheraf]

LordBraxton, on 24 May 2013 - 02:02 PM, said:

it is just Radar from

Halo Combat Evolved

who asked for this feature?

Have you ever wonder how the radar from Halo works?

[blinkin]

MuKen, on 24 May 2013 - 01:54 PM, said:

Yes with two separate sources that indicate direction you can get a pinpoint location without a distance measure. And the further apart those two sources are, the more accurate your location will be, the closer they are the less accurate, that's the point I've been making.

Say you have directional accuracy of +/- 5 degrees. You have two points that are 100m apart, and you are trying to locate a third point that is somewhere in the general area of a regular triangle (i.e. 100m away from each of them). Then you draw the intersection of their measured directions (which comes out to two cones of error), and the intersection of those two cones is pretty small, meaning that we have a pretty accurate guess of where that third point is.

Now say that those two measurement points are only 5m apart, trying to find a third point 100m away. Draw two +/- 5 degree directional cones pointing at the third point. What is the intersection? It is by comparison HUGE because the two directional cones have a lot of overlap. These two points are not able to draw a very accurate picture of where the third point is, despite having the same individual accuracy as in the first example.

that is all a matter of how precise your calculations and sensors are. tighter angles do require more precise measurements and calculations for accuracy, but i am generally assuming that the technology allows for as much precision as we want. this is scifi so we get to use the answer, "because science".