3 ms·

Now can we use this to do smog checks on cars as they drive so I can avoid the biennial chore of taking the car in to a shop?

idontwantthis 2y ago
Do they still actually analyze the gas? When I did mine they just plugged into the computer and it was done in 10 seconds.
- PaulHoule 2y ago
  The point of https://en.wikipedia.org/wiki/On-board_diagnostics https://en.wikipedia.org/wiki/On-board_diagnostics is that the engine control unit in your car is monitoring the operation of the engine and thinks it is in spec. If the computer says it is OK, it is OK, at least in most states. For years there has been talk about an OBD-III that would use the cellular network or something so your car can narc on you if it is out of spec https://www.hotrod.com/features/obd-iii-the-proposed-future-of-on-board-biagnostics-982-1639-22-1/ https://www.hotrod.com/features/obd-iii-the-proposed-future-... This has been stuck in purgatory with all the other proposals for universal telematics not least because of privacy concerns plus cell phone carriers being uninterested in anything other than "what's convenient for us" coverage.
  - ziddoap 2y ago
    >If the computer says it is OK, it is OK, at least in most states. The downside of this method (or upside, I guess, depending on where you stand), over the sniffer method, is that this is trivially bypassed. My race car, which is by no means emissions compliant, can pass this check with the press of a button.
    - Aurornis 2y ago
      States are beginning to roll out systems that do deeper checks on the firmware. Those, too, can be bypassed especially on older systems. However a lot of people are getting caught at emissions time now with cars that have been passing for years.
    - PaulHoule 2y ago
      Notably the functional test (measuring exhaust) can be gamed too, see https://en.wikipedia.org/wiki/Volkswagen_emissions_scandal https://en.wikipedia.org/wiki/Volkswagen_emissions_scandal Emission control is a balance between emissions, fuel economy and performance. You can give up some fuel economy and or performance at test time and enjoy better performance at the rest of the time if the system knows it is being tested.
      - deleted 2y ago
        [deleted]
PaulHoule 2y ago
I remember people from Sandia National Labs using LIDAR to monitor pollution around Albuquerque circa 1990. Turns out this been a thing for a long time: https://ntrs.nasa.gov/citations/19720026861 https://ntrs.nasa.gov/citations/19720026861 and is still going on https://iopscience.iop.org/article/10.1088/1748-9326/ab9cfd https://iopscience.iop.org/article/10.1088/1748-9326/ab9cfd https://idstch.com/security/lidar-technology-revolutionizing-pollution-monitoring-gas-detection-and-biochemical-attack-prevention/ https://idstch.com/security/lidar-technology-revolutionizing... I think in those cases you know what the pollutant is that is in a gas that you know what it is and want to make a quantitative determination whereas the system described in that paper is supposed to make sense of some random gas.
- aerostable_slug 2y ago
  Sandia and other labs have indeed been working on this type of MASINT collection for a long while. Their primary use case is remote characterization of effluents to determine if a given facility is being clandestinely used for things like chemical weapons production or nuclear materials enrichment.
datadrivenangel 2y ago
In Virginia they do this! They have devices that they'll put near highway on/offramps and rotate them between locations every few weeks or so.
BobaFloutist 2y ago
No, I want to add headlight lumens/angle checks and window tint checks to the smog check. It's an annoying chore but it's the one time car owners have to (semi-regularly) get their car looked at, we should take advantage of that.
- genewitch 2y ago
  I'm sorry, what's the issue with window tint?
  - stevenwoo 2y ago
    Some states have annual inspections of motor vehicles and on the list of items checked is headlight aim and window translucency.
  - BobaFloutist 2y ago
    Tinted front windows cause several problems: 1. It's harder to communicate with drivers with tinted windows and to check for their attention. This especially affects pedestrians and bicyclists who have to take pains to make sure they have a driver's attention before making their move, even when they have right of way. 2. You can't prosecute someone for a moving violation if they weren't identified as driving the car (because if a car is stolen for a joyride you don't want the original owner losing their license). Overly tinted front windows make it harder to consistently ID a driver, and let people get away with reckless driving. 3. Frankly it's annoying to not be able to see through cars. It makes certain turns iffier (because you can't see through the parked cars to identify oncoming traffic) and it makes it harder to predict a slow down if you can't see through the back windshield of the huge SUV completely obstructing your line-of-site. Obviously you should be maintaining a sufficient stopping distance to safely slow down, but that doesn't make it nicer to be able to see the slowdown/stop coming a bit before it arrives.

idontwantthis 2y ago

Do they still actually analyze the gas? When I did mine they just plugged into the computer and it was done in 10 seconds.

PaulHoule 2y ago
The point of https://en.wikipedia.org/wiki/On-board_diagnostics https://en.wikipedia.org/wiki/On-board_diagnostics is that the engine control unit in your car is monitoring the operation of the engine and thinks it is in spec. If the computer says it is OK, it is OK, at least in most states. For years there has been talk about an OBD-III that would use the cellular network or something so your car can narc on you if it is out of spec https://www.hotrod.com/features/obd-iii-the-proposed-future-of-on-board-biagnostics-982-1639-22-1/ https://www.hotrod.com/features/obd-iii-the-proposed-future-... This has been stuck in purgatory with all the other proposals for universal telematics not least because of privacy concerns plus cell phone carriers being uninterested in anything other than "what's convenient for us" coverage.
- ziddoap 2y ago
  >If the computer says it is OK, it is OK, at least in most states. The downside of this method (or upside, I guess, depending on where you stand), over the sniffer method, is that this is trivially bypassed. My race car, which is by no means emissions compliant, can pass this check with the press of a button.
  - Aurornis 2y ago
    States are beginning to roll out systems that do deeper checks on the firmware. Those, too, can be bypassed especially on older systems. However a lot of people are getting caught at emissions time now with cars that have been passing for years.
  - PaulHoule 2y ago
    Notably the functional test (measuring exhaust) can be gamed too, see https://en.wikipedia.org/wiki/Volkswagen_emissions_scandal https://en.wikipedia.org/wiki/Volkswagen_emissions_scandal Emission control is a balance between emissions, fuel economy and performance. You can give up some fuel economy and or performance at test time and enjoy better performance at the rest of the time if the system knows it is being tested.
    - deleted 2y ago
      [deleted]

PaulHoule 2y ago

I remember people from Sandia National Labs using LIDAR to monitor pollution around Albuquerque circa 1990. Turns out this been a thing for a long time: https://ntrs.nasa.gov/citations/19720026861 https://ntrs.nasa.gov/citations/19720026861 and is still going on https://iopscience.iop.org/article/10.1088/1748-9326/ab9cfd https://iopscience.iop.org/article/10.1088/1748-9326/ab9cfd https://idstch.com/security/lidar-technology-revolutionizing-pollution-monitoring-gas-detection-and-biochemical-attack-prevention/ https://idstch.com/security/lidar-technology-revolutionizing... I think in those cases you know what the pollutant is that is in a gas that you know what it is and want to make a quantitative determination whereas the system described in that paper is supposed to make sense of some random gas.

aerostable_slug 2y ago
Sandia and other labs have indeed been working on this type of MASINT collection for a long while. Their primary use case is remote characterization of effluents to determine if a given facility is being clandestinely used for things like chemical weapons production or nuclear materials enrichment.

datadrivenangel 2y ago

In Virginia they do this! They have devices that they'll put near highway on/offramps and rotate them between locations every few weeks or so.

BobaFloutist 2y ago

No, I want to add headlight lumens/angle checks and window tint checks to the smog check. It's an annoying chore but it's the one time car owners have to (semi-regularly) get their car looked at, we should take advantage of that.

genewitch 2y ago
I'm sorry, what's the issue with window tint?
- stevenwoo 2y ago
  Some states have annual inspections of motor vehicles and on the list of items checked is headlight aim and window translucency.
- BobaFloutist 2y ago
  Tinted front windows cause several problems: 1. It's harder to communicate with drivers with tinted windows and to check for their attention. This especially affects pedestrians and bicyclists who have to take pains to make sure they have a driver's attention before making their move, even when they have right of way. 2. You can't prosecute someone for a moving violation if they weren't identified as driving the car (because if a car is stolen for a joyride you don't want the original owner losing their license). Overly tinted front windows make it harder to consistently ID a driver, and let people get away with reckless driving. 3. Frankly it's annoying to not be able to see through cars. It makes certain turns iffier (because you can't see through the parked cars to identify oncoming traffic) and it makes it harder to predict a slow down if you can't see through the back windshield of the huge SUV completely obstructing your line-of-site. Obviously you should be maintaining a sufficient stopping distance to safely slow down, but that doesn't make it nicer to be able to see the slowdown/stop coming a bit before it arrives.