The Whiteboard

user55340

10:01 PM

@Ampt Which one?

Ampt

algorithm.co.il/blogs/ascii-plotter

user55340

Ahh...

user55340

2

A: Python ASCII plots in terminal

As @Benjamin Barenblat pointed out, there is currently no way using matplotlib. If you really want to use a pure python library, you may check ASCII Plotter. However, as I commented above, I would use gnuplot as suggested e.g. in this question. To use gnuplot directly from python you could eithe...

Ampt

it's an older version but the algorithm should work

enderland

if it's supposed to be an absurd blizzard tomorrow (after like 9am) is it wrong to stay home and work from home?

hmm this is actually a good question in some sense, the more I think about it (originally was going to write this as a joke here LOL)

user55340

10:07 PM

@enderland Heard that too.

user55340

8-12" here.

Ampt

ugh what?

enderland

only 5-9" here. but apparently 35+ mph winds (up to 50)

user55340

Just trust that @Ampt does a good job of testing the plows.

Ampt

but it's so nice today :(

user55340

10:08 PM

wunderground.com/US/WI/028.html#WIN

enderland

I heard on teh radio they are doing some sort of pilot program with plows here and I was... scarreeed for life (has to do with using iphones as cameras to capture road conditions, I guess)

user41796

All we're getting is some rain from that system. W00t!

enderland

you get more snow @MichaelT, we get more wind:

> Winds/visibility: winds are expected to shift Northwest late Thursday morning and quickly strengthen during the afternoon hours to 25 to 35 mph with gusts to near 50 mph

user15026

We had rain today. I hope we dont get more snow.

Ampt

UUUUUUUUGGGGGGGGGGHHHHHHHHHHHHHHHHHHHHHHHHH

enderland

10:10 PM

@Ampt please don't wear those boots. srslys :((

user55340

@enderland Did you read about that magnetic thing in California for the plows?

user55340

path.berkeley.edu/PATH/Research/snowplow

user55340

(its been discontinued -- too expensive)

user55340

> The Caltrans ASP is applying PATH's magnetic guidance system to help operators drive the plow even in a total whiteout by providing a visual display inside the cab of the plow's position relative to the sides of the road and to potential obstacles.

user55340

(and this was for mountain conditions)

enderland

10:11 PM

oh yeah driving in a whiteout WHAT COULD POSSIBLY GO WRONG

user55340

@enderland Actually, rather neat.

enderland

until some other person is on the road and you plow through them

user55340

In the cab you've got this display:

user55340

user41796

@MichaelT dumb Q - why don't they use a different technology? Aren't there some frequencies that wouldn't get reflected to all get-out from the snow? Infrared probably wouldn't work, but something higher up in the band ought to.

enderland

10:12 PM

oh it makes sense, but the problem isn't the plow - it's all teh other cars and morons out there too

user55340

If there's a car there, they've got problems already.

Jimmy Hoffa

@MichaelT I like that they diagrammed the road section nickname in there.

enderland

they've got 99 problems, but a snow plow going through them on autopilot isn't 1 of them?

user55340

That said:

user55340

> a computer data acquisition and information processing unit
sensors for measuring steering angle and vehicle movements
sensors for measuring the field of magnetic markers installed in the roadway
**radar sensors for obstacle detection**
human-machine interface (HMI).

enderland

10:13 PM

guess that's the problem with GPS not being spot on accurate huh, otherwise you could just do this with GPS

user55340

This was also pre-gps. I wouldn't want to trust a gps for this either.

enderland

airplanes do this sort of thing all the time when flying IFR

user55340

Landing? or flying?

enderland

both

user55340

See, flying you've got "ok, we're off by 10 feet" not a big problem...

enderland

10:15 PM

until you try landing ;)

user55340

off by 10 feet on the pass means you're also off by about 500 feet vertically too - you went over a cliff.

enderland

but then they're flying and then the 10 feet doesn't matter amitire

also I wonder what the primary restriciton on using GPS for something like that is

Ampt

@MichaelT farmers use GPS that's accurate to the cm

enderland

we use GPS in some of our equipment to get on the level of inches, but I think that's supplemented

damnit @Ampt :P

Ampt

it's not impossible, it's just that the government is very, very, very cautious about people with accurate GPS systems

something something missiles

user55340

10:17 PM

@Ampt How big, how fast, does it work when you are in a valley in the mountains? Or in heavy snowfall?

enderland

@Ampt farming uses land based stuff too to supplement GPS

user55340

Precipitation confuses the gps signal. Not a big deal for farmers - not planting in a whiteout...

user55340

But if you're slightly off in the lane goo.gl/maps/9km2k you've got quite a few problems with a plow.

user55340

In other bit - something to hunt up:

user41796

@MichaelT That's why you put industrial grade cow catchers on the plows, right?

Ampt

10:19 PM

@MichaelT I'm not sure that's 100% accurate

user55340

> A. Steinfeld, H.-S. Tan and B. Bougler, "Naturalistic Findings for Assisted Snowplow Operation," Proceedings of Human Factors and Ergonomics Society 45th Annual Meeting, Minneapolis, Minnesota, USA, October 2001.

user55340

@Ampt mountain valleys are still an issue.

enderland

@Ampt yeah even if you lose signal for a few seconds could be.. problematic

course you can predict pretty well I susecpt

user55340

Granted, this is about urban canyons - but its applicable to canyons too:

user55340

>
In certain constrained environments, GPS and EGNOS signals may be difficult to acquire. For example, when a vehicle is driving along a road hemmed in by rows of tall buildings, the vehicle’s onboard receiver may have difficulty picking up the satellite signals. Positioning in these environments, which are known as ‘urban canyons’, is poor. The use of EDAS compensates for this EGNOS reception problem. This kind of environment also generates a lot of multipath errors, whose effects can only be dealt with using receiver-level techniques. Receiver Autonomous Integrity Monitoring (RAIM) is use…

Ampt

10:23 PM

Urban canyons and real canyons are different though. spacing between satellites is key here

user55340

I do know there are places where my GPS wouldn't work in Cali Devils Postpile - I couldn't get enough satellite locks in the valley.

user55340

You need 4x satellites to get a fix. When 180 degrees of the sky is rock, this is a problem.

enderland

keep in mind you need something else to get the level of GPS accuracy you'd need to plow roads with it (which is what farmers also use, almost positive)

Ampt

I'm gonna go out on a limb and say that the GPS units on these trucks may have a large antenna than a consumer model

user55340

(I'd also point out that airplains typically aren't landing in canyons - urban or otherwise)

Ampt

10:25 PM

especially if in our theoretical world we were granted permission to use Military grade units

enderland

might as well just do heated roads then, way easier

user55340

@enderland In Mammoth Lakes area... they do.

enderland

yeah I always wish they do that, we get so much ice being in iowa

right along the freezing line always in winter (excet this year when we've been solidly below it)

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