Page 1 of 3 123 LastLast
Results 1 to 10 of 24

Thread: Standard set of CarPC sensors

  1. #1
    Moderator - CarPC News Penzance's Avatar
    Join Date
    Jan 2010
    Location
    Tennessee
    Posts
    159

    Standard set of CarPC sensors

    I would like to see a ‘minimum standard’ package of sensors developed for integration with a CarPC. I was thinking of naming it the OBE (On-board Environment) or OBS (On-board Sensor) board.

    As smartphones have evolved rapidly over the last few years, there has been some minimum expectations set as to standard hardware that comes with them. These have included things like GPS chips, electronic compasses, accelerometers, etc. If a developer can depend on these sensors being there, then it can lead to some cool things being developed - such as augmented reality apps, barcode scanners etc. In my opinion, the most interesting programming happening nowadays is the experimental/play software taking advantage of these new computer senses.

    In an automobile’s case, the sensors relating to the engine are already installed and accessible in a (somewhat) standard manner by using the car’s OBD port.

    But there are other sensors on the market that we should be able to bundle into a module (open source hardware?) to be bought and installed so that CarPC apps can take advantage of them. These could include:

    Temperature sensors, to include as a minimum:

    • a standard ambient (external) sensor
    • a cabin sensor
    • a computer case sensor (included in the computer hardware?)


    GPS

    3 axis accelerometer

    An Electronic compass

    Ambient light sensor

    Rain sensor (moisture?)

    Humidity sensor

    Car electrical system current sensor

    The spec for the package should also have the ability to accommodate multiples of any of these if required.

    If we can decide on a standard suite, it could be designed to be as simple as we now plug in a USB GPS. Instead of just getting our location from the USB connection, we can count on all of these other physical measurements as well.

    As an aside, on the software side Microsoft has a new ‘platform’ in Windows 7, which provides a standard way of accessing these kind of things : the Windows Sensor and Location Platform.
    I’m not sure if other OS’s have similar features. Regardless, we should be able to define a standard method of enumerating and interfacing with the board.

  2. #2
    Raw Wave
    Auto Apps:loading...
    justchat_1's Avatar
    Join Date
    Jul 2008
    Location
    Boston, Ma or NY,NY
    Posts
    2,359
    Quote Originally Posted by Penzance View Post
    Temperature sensors, to include as a minimum:

    • a standard ambient (external) sensor
    • a cabin sensor
    • a computer case sensor (included in the computer hardware?)
    Case sensor is included on the motherboard....external temp is standard on modern cars (OBDII) and a cabin sensor is accessible on most CAN buses in modern cars.

    Quote Originally Posted by Penzance View Post
    GPS
    Google GPS chip prices and compare them to your standard ebay gps

    Quote Originally Posted by Penzance View Post
    3 axis accelerometer

    An Electronic compass

    Ambient light sensor
    +1 could be very useful

    Quote Originally Posted by Penzance View Post
    Rain sensor (moisture?)
    again accessible via can bus...but could be cool in older cars (if you can find a standalone unit)

    Quote Originally Posted by Penzance View Post
    Humidity sensor
    for what?

    Quote Originally Posted by Penzance View Post
    Car electrical system current sensor
    Very expensive to measure the amount of current a modern car could be pushing

  3. #3
    Raw Wave
    Join Date
    Nov 2009
    Posts
    2,119
    Quote Originally Posted by Penzance View Post
    ....Car electrical system current sensor....
    Quote Originally Posted by justchat_1 View Post
    Very expensive to measure the amount of current a modern car could be pushing
    And I'd question WHY?
    Especially if not monitoring voltage(s).

  4. #4
    North of the land of Hey Huns
    Auto Apps:loading...

    Join Date
    Jun 2004
    Location
    Westminster, MD
    Posts
    2,144
    Quote Originally Posted by justchat_1 View Post
    Very expensive to measure the amount of current a modern car could be pushing

    You can get a 500amp shunt for around $30, which is plenty enough for even the most taxing electronic systems in a vehicle.
    "stop with the REINSTALLS, what do you think we got some lame-o installer!!!" - mitchjs
    RevFE
    My Shop

  5. #5
    Raw Wave
    Join Date
    Nov 2009
    Posts
    2,119
    You can get non-resistive DC Amp sensors even cheaper than that.

    The question still remains - WHY? What for? What use does it have?

  6. #6
    Raw Wave
    Auto Apps:loading...
    justchat_1's Avatar
    Join Date
    Jul 2008
    Location
    Boston, Ma or NY,NY
    Posts
    2,359
    Quote Originally Posted by malcom2073 View Post
    You can get a 500amp shunt for around $30, which is plenty enough for even the most taxing electronic systems in a vehicle.
    you would never want to use a shunt on a main battery cable...compare the gauge of those shunts to the gauge of the wire connected to it.

    +1 OldSpark....even cheaper its not useful information.

  7. #7
    Moderator - CarPC News Penzance's Avatar
    Join Date
    Jan 2010
    Location
    Tennessee
    Posts
    159
    Quote Originally Posted by justchat_1 View Post
    Case sensor is included on the motherboard....external temp is standard on modern cars (OBDII) and a cabin sensor is accessible on most CAN buses in modern cars.
    If the temps are accessible through the car's built in sensors, then I have no problems using them. I was thinking of the areas that might not have a way of measuring the temps. I was also going to recommend a 1-wire bus for this, so one could run just one pair of wires to wherever you need a sensor.

    Quote Originally Posted by justchat_1 View Post
    Google GPS chip prices and compare them to your standard ebay gps
    Yea, I see what you mean. Perhaps this could be optional on this board, and assumed to come in through the USB port, like the ODB connection.

    Quote Originally Posted by justchat_1 View Post
    again accessible via can bus...but could be cool in older cars (if you can find a standalone unit)
    As I said above, if it is available via the built in sensors, no problems. Most of the cars I see being worked on here are at least a few years old, however and it would be a useful sensor to have.

    Quote Originally Posted by justchat_1 View Post
    for what?
    I was thinking that it would be useful for input into an automated HVAC system.

    Quote Originally Posted by justchat_1 View Post
    Very expensive to measure the amount of current a modern car could be pushing
    I haven't looked at the costs right now - I'm looking for reasons why something like this would not be a good idea, and any other ideas on sensors to be added to the package.

    Quote Originally Posted by OldSpark View Post
    The question still remains - WHY? What for? What use does it have?
    Well, I'm looking for some way to display the health of the car's electrical system. I notice the Carnetix 2140 displays a lot of information about the electrics hooked up to it - perhaps that's where I got the idea from.

    Why do we do any of this? 'Cause it's cool , and 'cause we can.

  8. #8
    Raw Wave
    Join Date
    Nov 2009
    Posts
    2,119
    Current does NOT give any information about the health of a car's electrical system (hence why I asked).
    Voltage does. End of story.

    I'd rather not repeat yet again the Ys etc - I'd rather point out how often do you see ammeters in MODERN vehicles as opposed to voltmeters? (Even though that could be for other reasons including safety.)

    Or I could ask "so your ammeter shows 10A or 50A or 100A ot 200A - so what - how do you know if that is healthy or not?"
    Or how do you know if your alternator is overcharging (boiling) you battery?
    Or how do you know if it is undercharging?

    Ooops - I said I'd rather not repeat, yet there I go....
    Trust me, I'll beat you into submission....
    Resistance is Futile. (And in this case so is Amperage.)


    And for anyone that does want "shunts", I suggest Hall Sensors instead - eg under $20 - digikey Tamura 600A 5V.
    Similar devices are used for "zero-resistance" protection (fuse/circuit-breaker) circuits in hi-end hi-power audio systems (especially for plebs that have their audio PSU housed in their amps)

  9. #9
    Moderator - CarPC News Penzance's Avatar
    Join Date
    Jan 2010
    Location
    Tennessee
    Posts
    159
    Quote Originally Posted by OldSpark View Post
    ...Useful information...
    Thanks for that. What would you recommend as a sensor for this purpose?

  10. #10
    Raw Wave
    Join Date
    Nov 2009
    Posts
    2,119
    A voltmeter.

    If you have onboard intelligence (meaning uPC, PICAXE etc), they should have analog inputs.

    Analog inputs can be added to PCs if their soundcards (inputs) are unsuitable (ie, if they have capacitive coupling that blocks DC).

Page 1 of 3 123 LastLast

Similar Threads

  1. mplayer and videos
    By superman279 in forum LinuxICE
    Replies: 4
    Last Post: 05-13-2010, 10:57 PM
  2. How2 control CarPC from key fob....
    By NotchbackVW in forum Power Supplies
    Replies: 1
    Last Post: 09-21-2007, 05:27 PM
  3. Help with Mustang Carpc please
    By RickeyP21 in forum Newbie
    Replies: 6
    Last Post: 12-12-2006, 09:52 PM
  4. Replies: 33
    Last Post: 09-01-2005, 04:14 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •