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Author Topic: Can a self-guided vehicle navigate in a blizzard?  (Read 5259 times)

Offline Voxx

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Is there a vehicle that is self guided that can even navigate in blizzard like environments?

If so, how?  Which field spectrum does it operate at and what other functions does it have to help guide it?
« Last Edit: 29/07/2012 10:10:29 by chris »


 

Offline CliffordK

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #1 on: 15/07/2012 20:19:16 »
In a blizzard or "white-out", visible light is no longer useful for navigation. 
GPS may also be problematic.

What about radio waves?  Perhaps one could add radio emitters to the road pathway, as well as other vehicles on the road.

A train might also be less susceptible to weather limitations than other vehicles, as long as the tracks aren't too deeply buried.
 

Offline Voxx

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #2 on: 16/07/2012 03:40:32 »
Thank's Clifford punctual as usual.   ;)

Radio Waves, that's a very interesting theory and I like it.

What about Inferred?  Could you create a pathway of inferred lasers that would map out the terrain, a grid if you will?
 

Offline Geezer

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #3 on: 16/07/2012 04:03:56 »
 

Offline Voxx

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #4 on: 16/07/2012 05:41:11 »
Not quite self guided, but it could be quite easily.

http://www.govtech.com/e-government/Smart-Snowplows-Keep-the-Highway-to-Valdez-Alaska-Clear.html

Thank's Geezer, that was quite insightful.  Anyone have more thoughts?
 

Offline Mazurka

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #5 on: 16/07/2012 17:06:13 »
If you ignore Shanks Pony with its on board dataprocessing capabillity using such antiquated methods as map compass, altimeter and pacing and dead reckoning;

I would have though GPS would be your most reliable macro navigation tool coupled with radar (Geezers link)  or a laser scanner (lidar) (such as a Rigel VMX) for collision avoidance 
 
 

Offline Voxx

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #6 on: 18/07/2012 00:20:27 »
If you ignore Shanks Pony with its on board dataprocessing capabillity using such antiquated methods as map compass, altimeter and pacing and dead reckoning;

I would have though GPS would be your most reliable macro navigation tool coupled with radar (Geezers link)  or a laser scanner (lidar) (such as a Rigel VMX) for collision avoidance

I'm not saying I'm have adequate knowledge about guidance systems, but my concerns about the topic are these:

1: Can satellites pinpoint your exact location and send back "reliable" data even in a full scale blizzard?
2: How can satellites map pin point elevation, obstacles and wildlife.
3: What can be implemented to provide reliable trajectories with a rolling blizzard, unstable snowy terrain and still be in a timely manner.

These are just some of the thoughts I had at the top of my head.  I'm sure there are more that I'll think of eventually or someone may beat me to it.  I'm extremely thankful for the few that take time out of their schedule to help me understand the topics I ask.

Thanks, Voxx
 

Offline Mazurka

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #7 on: 18/07/2012 17:13:02 »
Ok, your thoughts raise some interesting points. 
Briefly
1 – yes (although see below)
2 – they cannot pin point obstacles and wildlife but can pin point elevation (if there is adequate number and spread of satellites) 
3 –  I am not sure I understand your point.

A vehicle that is designed to go from A to B has to know where A and B are relative to each other, so it has to be able to navigate according to some sort of map or chart programmed into it.  This could (in the case of the featureless plane such as the ocean) be fairly easy – simply two sets of co-ordinates, however, on land A to B as the crow flies might have any number of big fixed obstacles in the way – rivers, mountains, forestry, built development etc. so some sort of map is necessary – it does not matter whether this a survey map or a digital elevation model produced by one or more remote sensing techniques.  The actual method of navigation could be by any number (or combination) of ways compass, sextant, gps wheel revolutions etc. but sat nav is the most obvious choice to integrate into the electronic brain of a self guided vehicle.  In most circumstances sat nav coupled with some sort of dead reckoning would enable a vehicle to follow a road or similar feature.

To get from A to B safely – without damaging itself or wildlife – the vehicle needs to be able to avoid immediate hazards.  This has two elements – firstly imaging the immediate environment.  This could be (most simply?) achieved using electromagnetic radiation in either the radio part of the spectrum (radar) or the light (in the form of lasers) part of the spectrum (lidar).  The second element is determining what needs to be avoided – is that lump on the ground the sensors detected a stone that will be unaffected by a wheel rolling over it or a critter that will be squashed by a wheel rolling over it?  This would take considerable computing power and some very complex programming to deal with.  (The faster the vehicle travels and the more information it gathers the more computing power it is going to need.).  There may be other sensors such as passive infrared (a thermal camera) which could be useful to avoid wildlife or ultrasound which may be useful in imaging ice/ snow. 

To return to navigation it may help to understand how Sat Nav works
"GPS" (or more correctly) Global Navigation Satellite Systems (GNSS) work through an electronic receiver picking up a radio transmission from a satellite.  The transmission is a precise time code and position of the satellite, there is no other information transmitted (in either direction). 

If the receiver can get a signal from 3 or more satellites, it can triangulate its position.  The more satellites and the wider the spread of satellites gives a more accurate position.  A decent antenna (whcih could be deisgned into a vehicle) is also important for picking up the satellite's signal.    (Accuracy can be further enhanced by over sampling or by using a local ground based base station but that is probably not relevant to this question).  Weather does not really affect the signal although terrain and features such as trees(or even tall buildings) can, simply by blocking the signal and thus the number and spread of satellites from which the receiver gets the time & position information from. 

Elevation is harder to determine using sat nav (and from a mountian navigation perspective notoriously inaccurrate as compared to properly calibrated and frequent recallibration at known datums of a barometric system).  It is hard to see how this could be achieved automatically.

Simply because the human brain can do all of this really easily (or at least it can after a little training) it is easy to forget how complicated getting from A to B actually can be!  I am not certain that there is sufficient computing power and programme complexity (yet) to integrate all of the sensor inputs needed to design a functional self guided vehicle.
« Last Edit: 18/07/2012 17:19:41 by Mazurka »
 

Offline Voxx

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #8 on: 28/07/2012 00:30:41 »
Mazurka, that was very helpful!  Thank you very much for your input.

1: Thank you for confirming that question.
2: Alright so if they cannot pinpoint those obstacles I'll need another means like you said.

Radar: This could account for moving obstacles and give a rough picture of the area.
Inferred: This could be used as an overlay of the radar information giving a more accurate display of the area.
Ultrasound: I never even considered Ultrasound, thank you for that input.  Ultrasound could be used to calculate further information on stability in the environment.  What else can Ultrasound identify?
Elevation: I'll have to put up another thread on measuring elevation within real time on the fly.

3: This question was asking about ways of reading the environment.  This was partially answered with the Electromagnetic Spectrum, but can anyone think of any other ways of gathering information on environmental obstacles in real time?

Thank's for the input so far, this is as of now a theoretical transportation device.  I think there are currently projects of self guided cars though?  Still self guided snow mobiles seem slightly more complex as they are off road vehicles and have unpredictable obstacles that can cross paths.
 

Offline CliffordK

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #9 on: 28/07/2012 01:03:06 »
IR may not be as effective as you would like it to be.
The snow and ice would undoubtedly mask IR signals (with ice crystals looking uniformly cold).
If you saw a deer's IR signature, it might mean that you are VERY close.

I would think you might be better off with short wavelength signals.  For example UV, X-Ray, or even Gamma emitters placed on guard rails.  A passive weak gamma emitter might be the easiest to construct.

I don't know if you could use the short wavelength signals to detect obstacles though. 

I'm not sure about sonar guidance.  It is quite possible that heavy snow would also distort sonar signals.  For example, bubbles in water is supposed to be an excellent way to dissipate shock waves.  Is snow similar?
« Last Edit: 28/07/2012 01:07:01 by CliffordK »
 

Offline Voxx

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #10 on: 28/07/2012 09:13:09 »
IR may not be as effective as you would like it to be.
The snow and ice would undoubtedly mask IR signals (with ice crystals looking uniformly cold).
If you saw a deer's IR signature, it might mean that you are VERY close.

I would think you might be better off with short wavelength signals.  For example UV, X-Ray, or even Gamma emitters placed on guard rails.  A passive weak gamma emitter might be the easiest to construct.

I don't know if you could use the short wavelength signals to detect obstacles though. 

I'm not sure about sonar guidance.  It is quite possible that heavy snow would also distort sonar signals.  For example, bubbles in water is supposed to be an excellent way to dissipate shock waves.  Is snow similar?

Insightful as always Clifford, thank you for your input on the frequency.

Would there be any harmful effects on the environment or bio-cellular obstacles that get in front of the Gamma Emitter?

Can UV Light pass through Ice Crystals?

Is there any drawback to the interference with Gamma Emitter's as a guidance system platform?

Thank you for your continued input forum members!  :D
 

Offline CliffordK

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #11 on: 28/07/2012 11:15:38 »
I see notes that UV is reflected by snow (thus one gets sunburnt easily when skiing).  So, that is a bad idea.

Gamma is a type of radiation.  It is all dose dependent. 

Have you checked your radioactive gamma emitter in your house recently?  Yes, most people have a little chunk of radioactive americium in their homes.  Perhaps several as you may be required by law to have it in each of the bedrooms, as well as other rooms in your house.

The trick would be to get some with low enough activity to be visible as a beacon, without giving too great of a dose.  Thus, one could keep the risk for humans and animals minimal (hopefully less than having accidents).
 

Offline imatfaal

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #12 on: 28/07/2012 16:22:34 »
Couple of notes:

1.  Don't go searching for the Americium in your fire alarm - it is there but if you could get it out of its housing it is so small that you could ingest or inhale a bit, and that would be a problem.  No one has died from accidental americium exposure but alpha and gamma emitters are to be avoided - let's face it who wants to be the first?
2.  Americium is mainly used in fire alarms because it is an alpha-particle emitter - although some the stops on the  decay route to Neptunium are unstable and are gamma-ray emitters.  Americium is used for fire-alarms rather than Radium 226 as it is primarily an alpha emitter and its gamma emission is low
3.  All Americium used is synthetic
 

Offline Voxx

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Re: Self Guided Vehicle Even In A Blizzard?
« Reply #13 on: 28/07/2012 23:22:16 »
I see notes that UV is reflected by snow (thus one gets sunburnt easily when skiing).  So, that is a bad idea.

Gamma is a type of radiation.  It is all dose dependent. 

Have you checked your radioactive gamma emitter in your house recently?  Yes, most people have a little chunk of radioactive americium in their homes.  Perhaps several as you may be required by law to have it in each of the bedrooms, as well as other rooms in your house.

The trick would be to get some with low enough activity to be visible as a beacon, without giving too great of a dose.  Thus, one could keep the risk for humans and animals minimal (hopefully less than having accidents).

Alright, so the lower frequency range is out of the question for guidance within a snowy environment.

UV Lighting is reflective so it doesn't give an accurate guidance layout.

Gamma Ray's seem to be the best solution, I just need to have it carry high enough energy to pick up the environment, but low enough to cause little to no effect to organic life.

I'm still having a bit of trouble with the elevation, I'll give an example.

The machine is moving through a snowy night and according to the satellites the path in front of it is clear, but an avalanche a few hours previous has blocked off its desired route.  It will try and re-route a course of action, but how would it take into account lacking information from a satellite?

Also, how long of a sensory distance would the gamma rays be able to draw an accurate picture?  Like 5m, maybe 10?  Any input?

Would the image be 3D and would it be in 360 degrees?

Would X-Rays be a better solution than Gamma Rays?
« Last Edit: 29/07/2012 01:56:25 by Voxx »
 

Offline Mazurka

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Re: Can a self-guided vehicle navigate in a blizzard?
« Reply #14 on: 01/08/2012 12:26:21 »
I really cannot see any advantage in using gamma or xray over radio or light over the short ranges needed for collision avoidance.  Both radar and Lidar do suffer signal attenuation in snow, but as you can safely use a much stronger signal than gamma/ xray, this would be less of a problem & both are an off the shelf technology. 

As I said before, the actual imaging of the immediate environment is not very difficult, the trick for any system will be interpreting that information and then "acting" on that input (in the example you gave re routing itself) - in its simplest this could simply be backtracking and rerouting as a car based sat nav does - but this is not terribly efficient especially if the vehicle may be capable of crossing the obstacle (e.g. traversing avalanche debris) but would have to make a risk based decision as to whether to do so.

A stepping stone would be a machine that followed an asigned route using sat nav and fitted with collision avoidance sensors that stopped and radioed a human controller for instructions if those sensors were triggered by a fallen tree/ avalanche/ abandonded vehicle / enraged bear...
 

Offline richardtj

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Re: Can a self-guided vehicle navigate in a blizzard?
« Reply #15 on: 03/08/2012 09:05:42 »
Note that aircraft use radar to see and this penetrates water.  The issue here is that the speed through a mass such as water is different to that in air.  Similarly, GSM appears to work without any impact from weather.  An overlay of radar and something operating in the GSM (900 kHz) range may work.  The other issue is that many of these frequencies are already taken up/ sold, so theres no ground for using them commercially.
 

Offline Voxx

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Re: Can a self-guided vehicle navigate in a blizzard?
« Reply #16 on: 07/08/2012 18:51:42 »
Note that aircraft use radar to see and this penetrates water.  The issue here is that the speed through a mass such as water is different to that in air.  Similarly, GSM appears to work without any impact from weather.  An overlay of radar and something operating in the GSM (900 kHz) range may work.  The other issue is that many of these frequencies are already taken up/ sold, so theres no ground for using them commercially.

Yes, the vehicle would be able to figure out there was something in front of it with radar and it could plot out a course with GSM.  The main issue is how it will determine the obstacle in its way.  That's where IR or Gamma come in?
 

Offline imatfaal

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Re: Can a self-guided vehicle navigate in a blizzard?
« Reply #17 on: 08/08/2012 09:28:42 »
Voxx - you cannot use gamma radiation.  It tends to go straight through most things - ionizing a few things including important cellular components on its way.  Sonar?
 

Offline Mazurka

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Re: Can a self-guided vehicle navigate in a blizzard?
« Reply #18 on: 08/08/2012 11:32:38 »
Sorry to sound like a stuck record, but the video on this website is good example of what ground based laser scanenrs can do... http://www.land-scope.com/3d-scanning-and-modelling?gclid=CIud3N_o17ECFcVkfAod-38A1Q

This link http://www.riegl.com/nc/products/mobile-scanning/produktdetail/product/scannersystem/6/ shows the sort of kit that can be mounted on a vehicle (off the shelf)
There is quite a lot of research about the use of lidar for remote sensing the thickness of snow pack
 

Offline Voxx

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Re: Can a self-guided vehicle navigate in a blizzard?
« Reply #19 on: 21/08/2012 22:54:36 »
Voxx - you cannot use gamma radiation.  It tends to go straight through most things - ionizing a few things including important cellular components on its way.  Sonar?

Yeah, I started to think the same thing, so thank you for pointing that out.

The RIEGL VMX-250 eh...

An interesting show, but what spectrum do the lasers operate at and how does it measure altitude?
How quick is its recognition?
How far is its visual radius?
How quick can it re-route and what is its process for this?
What environments can it operate in?  An arctic like environment?

Also, thank you for the lidar comment I'll look into it.

I understand if you don't have the answers to all of these.  Thank you for the input.
 

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Re: Can a self-guided vehicle navigate in a blizzard?
« Reply #19 on: 21/08/2012 22:54:36 »

 

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