tablet powered car management system?

[ORANGEV8Z]

First off I'm glad to be back.  My car has been in pieces for years because I went through a time that I didn't have a place to work on it and to busy with other things.  I'm back and I have a welder now! and more skills and knowledge than I did before.  

 

I've started to do body work that I couldn't do before, shaving door handles and side markers etc.  I'm going to weld an aluminum dash and I had a thought(WARNING SOME PEOPLE INCLUDING I UNTIL YESTERDAY WOULD THINK THIS WAS A STUPID IDEA) 

 

It might be cool to have an android powered engine and car management system.  Now hear me out!

 

I was thinking a completely clean dash with no switches but a tablet mounted to the dash in such a way that it has a clean looking bezel around it so it looks as if it's molded into the dash(these things seem to be very reliable, maybe more reliable than a mechanical switch sometimes).  I'm talking complete control through the device.

 

-if I want to start the car I would enter an access code(the screen password) I could use a starter button on the screen.  Wipers, door poppers, headlights, everything could have a button on the android app.  

 

-would be very hard to steel because the docking wire could go anywhere, this is where the ignition wiring would go and the solenoid wire, and everything.  It could be made very secure.  

 

-the car door could be unlocked via bluetooth with a smart phone.

 

-maybe it would be possible to program things like dialing timing back with an electronic ignition?

 

-Custom emergency shut off settings could be made in the app.  A certain water temperature could be set or oil pressure where the car would shut off.  These could of course be over ridden in the app if a sensor stopped working.  

 

-maybe another lcd screen could be hooked up for the speedometer and tach gauges

 

-could control and easily adjust temperature fan kicks on

 

Another small computer would have to be mounted somewhere with a box containing the mechanical or solid state relays to turn the functions on.  Most of these functions are simple on off switching.  I really don't see why it would be any harder than controlling an rc car, and there are already cars that can be controlled by these devices. 

 

I'm usually against computers in cars(I like carbs) but in some ways this would actually make wiring and appearance cleaner and neater.  There are only 2 computers involved.  The android or apple tablet or smart phone and the one that decodes the micro usb signal and controls the relays.  Both should be easily replaceable should something go wrong, but computers seem to be very reliable.  It would actually make some things less complicated such as fan control, door popper switches, etc. because instead of having many little boxes around the car all would be controlled from one single point. 

 

I don't know maybe it's completely stupid?  I'm surprised but nothing like this seems to exist.  If it does please let me know!

[seattlejester]

I've actually thought about this a fair amount.

 

With an actual computer very plausible. Computers are used to control outputs all the time. Even with an arduino board, you could program it to do quite a few of the things desired. But with an android powered tablet controlling everything, you are going to have a problem. Program writing. Unless you know how to write an app, an app that would do external outputs using the android device, this is going to be extremely hard to pull off. You would have to take advantage of code that control an output, like the flashlight, blinking, camera, or sound output, and tap into that signal. There are not many apps with outputs using the data cable, some that receive data input via the cable, but not very many with outputs using the data cable. And in a data cable there are I think 4 wires? Doesn't leave much room to supply the tablet with all the sensor inputs it would need to manage an engine. Or enough outputs to actuate relays.

 

With that said, having an android as an interactive display already exists, you can start your car if it has bluetooth capabilities/cell capabilities with apps like the viper alarm systems. You can display all the important parameters that megasquirt outputs wirelessly with the shadow dash app (what I plan to do). With a computer or laptop running the outputs using a relay board as suggested, you could have the tablet run a display via a remote desktop app or something similar and control the outputs. 

 

There are a few people that have very integrated computers in their cars, if you search for carputers you can see what was involved. A lot involve putting in gps antennas for speed and gps signals, wireless receivers, a converter for the power supply, and that's only the hardware, from the few that I've seen the most integrated examples are done by programmers in their spare time. I met a guy that worked for microsoft that had a carputer, and tuned right off of it during a dyno session, very impressive.

Edited November 9, 2013 by seattlejester

[Jesse OBrien]

Bandwidth is the big problem with using a tablet. Megasquirt really is the right way to do this, with an Android interface that connects to it and offers your outputs. You could write a small Java application to manage the primary power relay that feeds megasquirt, and let megasquirt handle everything from there on out. Generally speaking, the ECU and Carputer are separate entities, for several reasons. ECU's are considered embedded devices, which are generally much more stable and reliable than machines that run several layers (operating system, driver layer, library layer, application layer). The Carputer should interface with the ECU, but should not run the ECU code.

 

You could reasonably easily make a 'body control unit' out of an Arduino, which wouldn't be a bad idea at all. It can process several inputs/outputs and control relays (with an output boost in voltage). I definitely wouldn't trust Android hardware (or operating systems) to directly an engine, though. As a tuning tool to write to an ECU, it's a great choice. As an ECU, there are far too many possible points of failure for me to have any faith whatsoever in that solution.

 

These are just my thoughts after 10 years of high-availability software development and systems administration. I'm no electrical engineer or ecu specialist, so someone else may be able to speak to that better than I can.

[zach90]

Isis power systems can be controlled via a iPad or other mobile device.

[BLOZ UP]

Bandwidth is the big problem with using a tablet. Megasquirt really is the right way to do this, with an Android interface that connects to it and offers your outputs. You could write a small Java application to manage the primary power relay that feeds megasquirt, and let megasquirt handle everything from there on out. Generally speaking, the ECU and Carputer are separate entities, for several reasons. ECU's are considered embedded devices, which are generally much more stable and reliable than machines that run several layers (operating system, driver layer, library layer, application layer). The Carputer should interface with the ECU, but should not run the ECU code.

 

You could reasonably easily make a 'body control unit' out of an Arduino, which wouldn't be a bad idea at all. It can process several inputs/outputs and control relays (with an output boost in voltage). I definitely wouldn't trust Android hardware (or operating systems) to directly an engine, though. As a tuning tool to write to an ECU, it's a great choice. As an ECU, there are far too many possible points of failure for me to have any faith whatsoever in that solution.

 

These are just my thoughts after 10 years of high-availability software development and systems administration. I'm no electrical engineer or ecu specialist, so someone else may be able to speak to that better than I can.

 

This. You do not want a critical process (running the car) running on a non-realtime, consumer OS.

[seattlejester]

^Especially if it can crash.