Forums

Embedded Linux for automotive

Started by pozz May 20, 2015
I'm searching for an embedded hardware that should run Linux OS on a 
vehicle. I don't need special features:

- VDC in
- RS232 port (not USB adapter)
- Ethernet
- SSD or soldered Flash (just to avoid magnetic HDD)
- analog audio input and output

I prefer a board with ready connectors, such as a PC desktop 
motherboard. I don't want to develop and produce a baseboard.

It should be nice to have a suitable case too for installation in a vehicle.

Maybe someone can suggest a good automotive DC/DC power supply that 
regulates the 24Vdc battery voltage of the vehicle in, most probably, a 
12Vdc for supplying the embedded computer.

Thank you for your suggestions.
On 5/20/2015 2:26 PM, pozz wrote:
> I'm searching for an embedded hardware that should run Linux OS on a vehicle. I > don't need special features: > > - VDC in > - RS232 port (not USB adapter) > - Ethernet > - SSD or soldered Flash (just to avoid magnetic HDD) > - analog audio input and output
There's nothing *listed* here that places particular constraints on whether the board runs in a vehicle or on a desktop -- other than power (assuming you want to get that from the vehicle itself). Are you intending on *using* these I/O's in ways that are intimately involved with that automotive environment? (electrical noise, temperature extremes, etc.)
> I prefer a board with ready connectors, such as a PC desktop motherboard. I > don't want to develop and produce a baseboard.
If you have uses in mind for those I/O's that are intimately tied to that environment (e.g., under the hood), you may have to. If, OTOH, you just want to plug a "box" into the lighter socket (showing my age, here... I know they don't call it that anymore :< ) and be able to "listen to music" (audio in/out) or transfer data to a laptop on the passenger seat (ethernet), then you have lots more possibilities (the power connection being the only real issue to address). Many "development kits" would fit the bill if power was addressed (e.g., *in* the "power connector")
> It should be nice to have a suitable case too for installation in a vehicle.
Ah... that changes the mix, a bit.
> Maybe someone can suggest a good automotive DC/DC power supply that regulates > the 24Vdc battery voltage of the vehicle in, most probably, a 12Vdc for > supplying the embedded computer.
Huh? Here (US) most vehicles are 12VDC powered. Most of your stated requirements can be addressed with a 5V-powered board (e.g., derive power from the USB jack present in many newer vehicles -- even if you never transfer any *data* over that connection!)
> Thank you for your suggestions.
On 21/05/15 16:13, Don Y wrote:
> On 5/20/2015 2:26 PM, pozz wrote: > >> Maybe someone can suggest a good automotive DC/DC power supply that >> regulates >> the 24Vdc battery voltage of the vehicle in, most probably, a 12Vdc for >> supplying the embedded computer. > > Huh? Here (US) most vehicles are 12VDC powered. Most of your stated > requirements can be addressed with a 5V-powered board (e.g., derive power > from the USB jack present in many newer vehicles -- even if you never > transfer any *data* over that connection!) >
Perhaps his system is for larger vehicles (lorries, trucks, etc.), which are usually 24V rather than 12V? Anyway, if you are powering from a car or truck's electrical system, remember that the 12V or 24V supply varies substantially depending on the state of the battery, and the charge from the alternator. To be safe for use in a 24V truck system, you need to accept ranges from 18V to 36V, and be ready for a lot of high spikes (such as when using the starter motor).
On Wed, 20 May 2015 23:26:10 +0200, pozz <pozzugno@gmail.com> wrote:

>I'm searching for an embedded hardware that should run Linux OS on a >vehicle. I don't need special features:
For vehicle mounted system, you need to consider at least * Vibration, check for PCB and connector support * Dust * Temperature range, does the clock oscillator start at -40 C. How does it handle temperatures much above +50 C when the vehicle is parked in the sun ? * Condensation: do you need coated PCBs, how is moisture drained out of the box * Input voltage protection
> >- VDC in >- RS232 port (not USB adapter) >- Ethernet >- SSD or soldered Flash (just to avoid magnetic HDD) >- analog audio input and output > >I prefer a board with ready connectors, such as a PC desktop >motherboard. I don't want to develop and produce a baseboard. > >It should be nice to have a suitable case too for installation in a vehicle. > >Maybe someone can suggest a good automotive DC/DC power supply that >regulates the 24Vdc battery voltage of the vehicle in, most probably, a >12Vdc for supplying the embedded computer.
Starting a big cold diesel may cause a severe drop of the battery voltage. I would suggest after the input voltage filtration a series diode, a _big_ electrolytic capacitor rated at 35 V and specified for high temperatures. After that a DC/DC converter to 5 V or whatever the PCB needs. Check that the converter minimum voltage is low (say 8..12 V) so that it can fully utilize the energy stored in the capacitor. The smaller the PCB current consumption, the longer the capacitor charge will last or you can use a smaller capacitor. A small power consumption will also help in cooling the system at high temperatures. In addition to engine start voltage drops, this diode, capacitor, converter circuit also makes it easy to perform an orderly shutdown in case the main +24 V is lost. Of course, you need a direct, filtered feed from the 24 V supply line to start the shutdown sequence to save files etc.
pozz <pozzugno@gmail.com> wrote:

> I'm searching for an embedded hardware that should run Linux OS on a > vehicle. I don't need special features: > > - VDC in > - RS232 port (not USB adapter) > - Ethernet > - SSD or soldered Flash (just to avoid magnetic HDD) > - analog audio input and output > > I prefer a board with ready connectors, such as a PC desktop > motherboard. I don't want to develop and produce a baseboard. > > It should be nice to have a suitable case too for installation in a vehicle. > > Maybe someone can suggest a good automotive DC/DC power supply that > regulates the 24Vdc battery voltage of the vehicle in, most probably, a > 12Vdc for supplying the embedded computer. > > Thank you for your suggestions.
check the beagle board. Ciao Jack -- Yoda of Borg am I! Assimilated shall you be! Futile resistance is, hmm?
Il 22/05/2015 09:37, upsidedown@downunder.com ha scritto:
> On Wed, 20 May 2015 23:26:10 +0200, pozz <pozzugno@gmail.com> wrote: > >> I'm searching for an embedded hardware that should run Linux OS on a >> vehicle. I don't need special features: > > For vehicle mounted system, you need to consider at least > > * Vibration, check for PCB and connector support > > * Dust > > * Temperature range, does the clock oscillator start at -40 C. How > does it handle temperatures much above +50 C when the vehicle is > parked in the sun ? > > * Condensation: do you need coated PCBs, how is moisture drained out > of the box > > * Input voltage protection > >> >> - VDC in >> - RS232 port (not USB adapter) >> - Ethernet >> - SSD or soldered Flash (just to avoid magnetic HDD) >> - analog audio input and output >> >> I prefer a board with ready connectors, such as a PC desktop >> motherboard. I don't want to develop and produce a baseboard. >> >> It should be nice to have a suitable case too for installation in a vehicle. >> >> Maybe someone can suggest a good automotive DC/DC power supply that >> regulates the 24Vdc battery voltage of the vehicle in, most probably, a >> 12Vdc for supplying the embedded computer. > > Starting a big cold diesel may cause a severe drop of the battery > voltage. I would suggest after the input voltage filtration a series > diode, a _big_ electrolytic capacitor rated at 35 V and specified for > high temperatures. > > After that a DC/DC converter to 5 V or whatever the PCB needs. Check > that the converter minimum voltage is low (say 8..12 V) so that it can > fully utilize the energy stored in the capacitor. > > The smaller the PCB current consumption, the longer the capacitor > charge will last or you can use a smaller capacitor. A > small power consumption will also help in cooling the system at high > temperatures. > > In addition to engine start voltage drops, this diode, capacitor, > converter circuit also makes it easy to perform an orderly shutdown in > case the main +24 V is lost. Of course, you need a direct, filtered > feed from the 24 V supply line to start the shutdown sequence to save > files etc.
Infact, I need a ready-to-use solution. One that includes a suitable power supply, mainboard, connectors and so on.
Il 22/05/2015 08:41, David Brown ha scritto:
> On 21/05/15 16:13, Don Y wrote: >> On 5/20/2015 2:26 PM, pozz wrote: >> >>> Maybe someone can suggest a good automotive DC/DC power supply that >>> regulates >>> the 24Vdc battery voltage of the vehicle in, most probably, a 12Vdc for >>> supplying the embedded computer. >> >> Huh? Here (US) most vehicles are 12VDC powered. Most of your stated >> requirements can be addressed with a 5V-powered board (e.g., derive power >> from the USB jack present in many newer vehicles -- even if you never >> transfer any *data* over that connection!) >> > > Perhaps his system is for larger vehicles (lorries, trucks, etc.), which > are usually 24V rather than 12V? > > Anyway, if you are powering from a car or truck's electrical system, > remember that the 12V or 24V supply varies substantially depending on > the state of the battery, and the charge from the alternator. To be > safe for use in a 24V truck system, you need to accept ranges from 18V > to 36V, and be ready for a lot of high spikes (such as when using the > starter motor).
Yes, I have 24V battery and I need a ready-to-use DC/DC power supply for automotive application. Maybe one product that reads the ignition signal and automatically power-on/off the board.
On 5/22/2015 10:54 AM, pozz wrote:
> Il 22/05/2015 09:37, upsidedown@downunder.com ha scritto: >> On Wed, 20 May 2015 23:26:10 +0200, pozz <pozzugno@gmail.com> wrote: >> >>> I'm searching for an embedded hardware that should run Linux OS on a >>> vehicle. I don't need special features: >> >> For vehicle mounted system, you need to consider at least >> >> * Vibration, check for PCB and connector support >> >> * Dust >> >> * Temperature range, does the clock oscillator start at -40 C. How >> does it handle temperatures much above +50 C when the vehicle is >> parked in the sun ? >> >> * Condensation: do you need coated PCBs, how is moisture drained out >> of the box >> >> * Input voltage protection >> >>> >>> - VDC in >>> - RS232 port (not USB adapter) >>> - Ethernet >>> - SSD or soldered Flash (just to avoid magnetic HDD) >>> - analog audio input and output >>> >>> I prefer a board with ready connectors, such as a PC desktop >>> motherboard. I don't want to develop and produce a baseboard. >>> >>> It should be nice to have a suitable case too for installation in a >>> vehicle. >>> >>> Maybe someone can suggest a good automotive DC/DC power supply that >>> regulates the 24Vdc battery voltage of the vehicle in, most probably, a >>> 12Vdc for supplying the embedded computer. >> >> Starting a big cold diesel may cause a severe drop of the battery >> voltage. I would suggest after the input voltage filtration a series >> diode, a _big_ electrolytic capacitor rated at 35 V and specified for >> high temperatures. >> >> After that a DC/DC converter to 5 V or whatever the PCB needs. Check >> that the converter minimum voltage is low (say 8..12 V) so that it can >> fully utilize the energy stored in the capacitor. >> >> The smaller the PCB current consumption, the longer the capacitor >> charge will last or you can use a smaller capacitor. A >> small power consumption will also help in cooling the system at high >> temperatures. >> >> In addition to engine start voltage drops, this diode, capacitor, >> converter circuit also makes it easy to perform an orderly shutdown in >> case the main +24 V is lost. Of course, you need a direct, filtered >> feed from the 24 V supply line to start the shutdown sequence to save >> files etc. > > Infact, I need a ready-to-use solution. One that includes a suitable > power supply, mainboard, connectors and so on.
I think that is going to be hard to find. The power supply should not be a big deal. Finding one with a shutdown signal shouldn't be too hard. But finding all this bundled up in one unit will be a bit tough. I worked on a unit for military apps and the PSU requirement was mostly driven by the environment encountered in vehicles. The spec on the input voltage was up to 30 volts continuous (or thereabouts) but the surge was for 100 volts. When a starter is disengaged there is a huge spike of voltage produced by the coil which arcs across the contacts and travels throughout the power system. They call this "load dump". It should not be ignored. Even in a 12 volt system the load dump can be over 50 volts. What are your other requirements? Would you be happy with something like a Beagle board or a raspberry Pi? Or do you need something with more performance like a PC motherboard in an ITX form factor? -- Rick
Am 20.05.2015 um 23:26 schrieb pozz:
> I'm searching for an embedded hardware that should run Linux OS on a > vehicle. I don't need special features: > > - VDC in > - RS232 port (not USB adapter) > - Ethernet > - SSD or soldered Flash (just to avoid magnetic HDD) > - analog audio input and output > > I prefer a board with ready connectors, such as a PC desktop > motherboard.
So get one. Car PCs are available to all kinds of specifications.
pozz wrote:

> I'm searching for an embedded hardware that should run Linux OS on a > vehicle. I don't need special features: > > - VDC in > - RS232 port (not USB adapter) > - Ethernet > - SSD or soldered Flash (just to avoid magnetic HDD) > - analog audio input and output > > I prefer a board with ready connectors, such as a PC desktop > motherboard. I don't want to develop and produce a baseboard. > > It should be nice to have a suitable case too for installation in a vehicle. > > Maybe someone can suggest a good automotive DC/DC power supply that > regulates the 24Vdc battery voltage of the vehicle in, most probably, a > 12Vdc for supplying the embedded computer. > > Thank you for your suggestions.
What are you going to do with the embedded hardware? w..