Tablet install to replace sat nav (Build thread)

[igeak691]

This thread is to document my journey as I replace the sat nav screen with a tablet, so that the user interface is up to date with the times.

I found a UI that I think I can use and fortunately, the original designer shared his files to be freely editable.

Here's what I have so far, although I've been tweaking it constantly and have about two weeks before the tablet arrives:

On the left, there will also be a widget for the time and date, as well as current temperature and weather conditions. To make this work, I will be using Nova Launcher and swipe gestures to pull up the app drawer, and another swipe gesture to get to the notifications bar.

In terms of hardware, there have been many installs where heat became an issue for the tablets, specifically for battery health. I have since decided to completely remove the battery and have the tablet hardwired into the car. The 12v cigarette plug remains live, and so will the tablet. At standby, the tablet draws a few watts which, for a convertible with a large battery to accommodate soft top lowering and raising, shouldn't be an issue. If I do run into issues, I will install the battery back into the tablet.

To help with the heat issue, I will also put a hose from the AC vent that will run into the sat nav housing. This should help a little bit, and is easy to implement so I figured why not.

The audio from the tablet will run into the aux in of the radio, and thus should be fine for any audio needs. Where I live, the tablet will be able to access wifi virtually anywhere I go, so 4g internet subscription won't be necessary. If needed, I can turn my phone into a wifi hotspot and the tablet can connect to it.

For those who are wondering why I'd do this, the sat nav offers little that the tablet cannot replace. Also the MK4 dvd based computer systems will more than offset the costs of this project. The size of the z4 also lends perfectly to have that screen be a touchscreen

Suggestions are welcome as this project is going to take roughly a month from now to finish. I'll try to document any hiccups along the way, and what solutions I come up with for problems that may arise.

 

[GreyZed]

To help with the heat issue, I will also put a hose from the AC vent that will run into the sat nav housing. This should help a little bit, and is easy to implement so I figured why not.

But what about in the winter when you need the heater on max? :?

 

[igeak691]

I've always been more of a fan of seat heaters in the winter. Plus if I do use the heat, it's only for a short bit to warm up the cabin.. that will only be a good thing so that the tablet isn't in subzero temperatures.

Keep in mind that this hose method probably won't work very well anyway.. I don't see it ever making it too cold to use the tablet in the summer, or too hot that it overheats in the winter.

 

[si-forks]

Looking forward to seeing the results would love a tablet in my Z4

sent by galaxy S4 on tapatalk

 

[Bradman]

Very cool idea!

I've been giving serious thought to using a Raspberry Pi coupled to the original Sat Nav screen... Raspberry Pi can be placed somewhere cool (cubby hole between the seats?), runs off a 5V USB lead (plenty of USB to cigarette lighter cables out there, but need to check if they drop the voltage) and can output to a composite video screen, with audio output into the aux of the BMW radio. The 'Pi also has something a tablet doesn't: GPIO ports! Use these to take feeds from various sender units (oil pressure / temperature, voltage, water etc) and you could have a screen full of extra dials, if that's your thing. You lose the touch screen, but you should be able to use a stock BMW joystick (like in the later BMWs) to navigate any menus, or even a mini Bluetooth keyboard and track pad... Software exists out there, or for those of you who can program and fancy writing your own interface, the Pi comes with Python BASIC which is a doddle to use...

http://www.raspberrypi.org/forums/viewtopic.php?f=41&t=70517

Raspberry Pi is very cheap to buy, but sadly for me I don't have a sat nav screen to play with, and they're not so cheap

 

[sk93]

hey dude!

Very interested in this... what tablet (and also what OS) are you using?

I'm running with a Hueweii Ascend Mate and Android.
Currently running car dashdroid, and whilst it's ok - it's not perfect, so am looking to replace.

I'm a developer by trade, but never developed on android, so starting a full homescreen/launcher from scratch seemed a bit daunting for me...

anyways.. very interested!

 

[Adamski]

Cracking idea, and whilst it's of little use for my zed, I'm really interested to see the results


Sent from my iPhone using Tapatalk

 

[adam1985]

Very cool idea!

I've been giving serious thought to using a Raspberry Pi coupled to the original Sat Nav screen... Raspberry Pi can be placed somewhere cool (cubby hole between the seats?), runs off a 5V USB lead (plenty of USB to cigarette lighter cables out there, but need to check if they drop the voltage) and can output to a composite video screen, with audio output into the aux of the BMW radio. The 'Pi also has something a tablet doesn't: GPIO ports! Use these to take feeds from various sender units (oil pressure / temperature, voltage, water etc) and you could have a screen full of extra dials, if that's your thing. You lose the touch screen, but you should be able to use a stock BMW joystick (like in the later BMWs) to navigate any menus, or even a mini Bluetooth keyboard and track pad... Software exists out there, or for those of you who can program and fancy writing your own interface, the Pi comes with Python BASIC which is a doddle to use...

http://www.raspberrypi.org/forums/viewtopic.php?f=41&t=70517

Raspberry Pi is very cheap to buy, but sadly for me I don't have a sat nav screen to play with, and they're not so cheap

Only issue i can see with a pi is boot time. I use one with xbmc as a media centre and it takes a good minute to boot fully. By this time you would likely be driving already.
If you wanted to test it you could get one of there http://www.amazon.co.uk/PiTFT-Mini-Kit-Touchscreen-Raspberry/dp/B00H9B1DTAto try and get the pi to display data from sender ports

 

[NeilP]

Interested to see where this goes. That UI is fantastic by the way!

 

[Bradman]

Only issue i can see with a pi is boot time. I use one with xbmc as a media centre and it takes a good minute to boot fully. By this time you would likely be driving already.
If you wanted to test it you could get one of there http://www.amazon.co.uk/PiTFT-Mini-Kit-Touchscreen-Raspberry/dp/B00H9B1DTAto try and get the pi to display data from sender ports

Yes, boot time is a problem - I don't boot into a gui on mine, but it still takes a good half minute... That little touch screen looks good though!

 

[sk93]

I use an arduino and a pi in my car.

arduino powers up the tablet and the pi on ignition.
boot times disappear that way

 

[igeak691]

The point of this exercise was to proof a concept that a tablet doesn't have to look like android system. The implementation won't be easy and will require much tinkering, but that's part of the fun for me. The UI is my favorite part, as I think doesn't take away from the value of the car if it doesn't look like a regular tablet was put into the dash. Right now, the tablet that is on its way is a clone of the galaxy note 2, it was the best I could find to fit the screen, and about $115 vs the cheapest I could find the ascend mate at $190.

sk93, do you have more videos of your implementation? I've watched a few vids of yours, but some of them need a direct link and don't show up on your youtube channel. Would love to see any more pictures/videos you may have made during the making of your screen. One thing that I admire about your build that I will not be able to replicate is using the arduino to automate the screen moving. I've always been interested in arduino based boards and using them for various things, but the learning curve is pretty steep for me. I would LOVE to know how much a board that automatically senses the car is on and turns up the screen costs.

Also sk93, if you have your phablet with the battery still in it, aren't you worried that the heat will kill the battery over time making it expand and possibly burst/bust something? That's the main reason I am removing the battery altogether. The car gets way too hot in the summer for me to comfortably leave any lithium based battery inside the car at those temperatures.

As for boot time, this tablet will be on 24/7.. it will go into deep sleep if in face down orientation so that it only consumes a few watts. Boot time ends up being a nonexistent 2 seconds. After the screen turns on, it will be set to automatically play from pandora, but open up the app torque (of course all these settings can be customized after the installation).

 

[robbansson]

what UI is that?

 

[danmiddle2]

UI looks good - will the shortcuts be customisable?

Seen this - http://www.z4-forum.com/forum/viewtopic.php?f=29&t=56746 ?

 

[dhobbs]

I've always thought that a tablet would be a great idea for the sat nav and music for a car.
Especially if there was an adaptor you can just plug your tablet into and remove it later.
Getting car information would be a bonus as would be integration with the steering wheel controls.

Best of luck.

 

[danmiddle2]

For anyone else interested, there are some details on a very similar user interface here (about half way down):
http://www.mp3car.com/show-off-your-project/152814-bmw-e46-android-install-includes-build-log-diy-2.html

It appears to be a wallpaper with transparent widgets / launcher icons. Just had a play and managed to re-create something not entirely dis-similar. For now I think I'll be sticking with Dashdroid, but very interested to see what you come up with igeak691

For me, something like Dashdroid with a BMW-looking skin would be ideal.

 

[NeilP]

Well that's a forum I haven't frequented in a long time!

I miss the good old days of a car pc running cetrafuse on top of windows xp. :?

 

[sk93]

Also sk93, if you have your phablet with the battery still in it, aren't you worried that the heat will kill the battery over time making it expand and possibly burst/bust something? That's the main reason I am removing the battery altogether. The car gets way too hot in the summer for me to comfortably leave any lithium based battery inside the car at those temperatures.

As for boot time, this tablet will be on 24/7.. it will go into deep sleep if in face down orientation so that it only consumes a few watts. Boot time ends up being a nonexistent 2 seconds. After the screen turns on, it will be set to automatically play from pandora, but open up the app torque (of course all these settings can be customized after the installation).

I am concerned about the heat, but not overly..
my question would be how long could you realistically leave the phablet on a "live" connection, with the car turned off, before the car battery would die?
I know it's not a question of hours, but it's often the case I can leave my car for a good couple of days (maybe even two weeks) without it starting.
what I'd hate to do is come back from a holiday to a dead car battery!


In regards to removing the battery entirely - what sort of voltage / current is required do you think?


next question is how are you going to get it to wake from deep sleep?
tasker and the like can do it, but only on certain triggers.
the movement sensors are disabled by android when in deep sleep, so tilting is out of the equation.
I also can't get it to turn on via bluetooth.


If you've got some tasker profiles I could steal, I'd be very, very happy!

 

[chriswoodward]

Just for those worried about battery life, this is quite a common mod for an RX8 and I had done it to mine using a Nexus 7 Tablet, I never had any problems with the battery.

This thread may have some useful info, obviously not the same car but handy for power info etc

http://www.rx8ownersclub.co.uk/forum/viewtopic.php?f=30&t=48360&hilit=nexus+7%23

 

[igeak691]

danmiddle2 yes that's where I got the UI from. I think it looks a lot better than dashdroid. It's definitely a workaround like I said and not just a different launcher. With some software tweaking it can be made to look like stock.

sk93 I am using a 12v to 5v convertor that handles up to 15w. That's more than enough juice that the tablet can be using at any moment. I've even seen people using 5v 2a with no issue but I figured overkill is better than under.

Waking up from deep sleep is easy with tasker. You can set it up so that it keeps certain sensors on even when android is asleep. For me, it'll be the proximity sensor that gets used so that the screen is off when the screen is down, but turns on when the screen is up. If it ever turns on while I have my hands touching the screen, I'll just have to use the accelerometer instead so the tilt axis will turn it on (I will see which one works better and report)

I can post up my tasker profiles after I work out all the tweaks. I've been playing with it for my nexus 5, and certain things are buggy so will have to see how it fares when the parts arrive.