Tablet Carputer

A little while ago I bought a Samsung Galaxy Tab2 10.1" tablet. Around the house I use it for controlling the Music Server and control the whole house audio. I read many articles on using a tablet in the car, so I decided to give it a whirl. Boy, do I really like the results...see below for details.

For a Carputer, the primary use was to be able to play music. The second, and equally important was to have some form of GPS. Well, with the Samsung, I got more than I bargained for. To start, the Samsung tablet is running Androids OS 4.1.1, and they were generous to load the device with a plethora of apps to start.

Now in my 2012 RAV4, is the basic audio system. It consists of 6 speakers (tweeter/6.5" mids up front, 6.5" coax in the back doors), and connected to a Bluetooth enabled headunit. There is a USB streaming media port, as well as a 3.5mm stereo AUX port. The system has basic steering wheel controls. Issues with the system:

1. To make a phone call requires a slew of button pushing and knob turning at the head unit...cannot be done via steering wheel controls...this takes the drivers focus away from the road.

2. System can register multiple Bluetooth devices, but can only control one device at a time.

3. Speaker output is awefull...and I would love to just update the speakers to better sounding ones. But that has nothing to do with this project.

So, after reviewing lot's of setup on the web, I created my own "RAVputer". So without adieu, enjoy what I did below.

The basic view of the Carputer screen is:

The system has the abilities to not only be used for playing music, it also can perform navigation, be the vehicle management system, and integrate with my cell phone for dialing and accepting calls. Below is the breakdown of the various devices that this Carputer can run.

GPS Navigation

The top right corner icon is for bringing up the GPS Navigation app called NavFree. It is a free navigation service for both Android and Apple products. I tested it out along with my dated Magellan Maestro, and it fared pretty well with it.

Simple GPS view, no route selected, but the options are there.

Phone Dialer

The app icon right below the navigation icon opens the application called Tablet Talk. This app integrates the tablet to my cell phone via bluetooth, and allows the ability to dial out, and receive phone calls, as well as sending and receiving text messages. It is much more convenient to be able to type a text message on the larger screen, but of course, not while driving...that would just be silly. But never the less, to make phones calls is much easier using this than with the stock system. Chalk this up to issue 1 solved.

The view of Tablet Talk Dialer. You can use the dialer to search for a contact, or dial the number. Only problem is that it currently won't answer a call, or end a call...I have to do that from the phone.

Multi-Media Player

Pressing on this icon will open up aVia Media Player. This app is a UPnP/DLNA media player that can be used in conjunction with my SqueezePlug Raspberry Pi video server. This will allow for the streaming playback of video and music from the SqueezePlug harddrive. Also if sitting in my driveway, and connected to my home network, I can play media content right from my UnRAID server.

The start view for aVia Media. From here I'd select "My Sources" to verify that the system is connected to the SqueezePlug Pi. Then I can select audio or video.

Internet Radio

This icon will open the Tune-in streaming radio application and allow for the playback of internet streaming radio stations. This works provided I'm in a WIFI hotspot, such as home, or other recognized location, or free WIFI area like McDonald's or Tim Horton's.

Music Player

The icon in the lower right corner is the PowerAmp music player status. Clicking on the icon will open PowerAmp for configuring playback of music within the tablets memory. It is considered one of the best music players for the Android platform.

Awesome view of PowerAmp.

Engine Monitor/Management

This icon in the lower left will access the engine management app called Torque. This powerful application communicates to the vehicles ECU via a bluetooth dongle plugged into the vehicles OBDII socket. OBDII is a standard protocol across almost every major car manufacturer. This app gives feedback to the various system sensors, and gauges, such as RPM, speed, throttle, engine temps, ECU errors are just a few things this program can monitor and report on. There are plenty of settings, many which I don't have an understanding too at this time.

Torque view. System wasn't connected to vehicle ECU at the time of this screen capture. All of these gauges get live feedback from the ECU. Starting top left: RPM's, Speed, Instantaneous horse power, Throttle

bottom left: Engine Coolant temperature, Transmission Temperature, Intake Manifold Temperature, Boost

Along with the many apps, are the various widgets as indicated:

Clock

This is one of the pre-installed widgets from Samsung, which I think looks rather nice.

Weather Widget

This is another pre-installed Samsung widget, which allows for weather updates from Accuweather.com. It will update when the tablet is within a WIFI area.

Volume Control

Volume control of the tablet can be done by this free widget. I can also control the vehicle system volume on the steering column.

Additional

As indicated in the image above, some of the additional apps that are installed and running in the background are Desktop VisualizeR Widget and Tasker.

Desktop VisualizeR Widget was installed and allows for the creation of those cool image icons for selecting the different functions on this screen. This application will take an image, and integrate it with the selected app.

Tasker is an automation application. It will perform specific tasks when triggers are met. Currently it is used to pause media playback when a call is received or initiated. When the call is terminated, Tasker will toggle the pause, and resume playing. I've also created some task as to what the tablet should do when the 3.5mm stereo jack is connected/disconnected from the tablet.

I've also recently updated and created a new home screen. The background is the Audio Glow Live Wallpaper. This wallpaper appears as colorful EQ bars, that rise and fall with the music played from PowerAmp or Avia. It also shows the current artist and track being played (PowerAmp only). I've included on this home screen, the volume widget, described above and three Media Buttons widgets for play/pause toggling, next and previous track selection. I tried to keep this screen as minimal so not to take away from the background visual. Swiping your finger across the screen will then take you to the screen with the above choices. Tasker has been set up in such a way that when in PowerAmp, after 30 seconds, will jump to this home screen. I figure, 30 seconds should be enough time to select some music to listen to.

Mounting

The next step after getting all these great apps working, was to figure out how to mount the tablet in the car, without it serving as a blind spot since it is a pretty large screen. I had originally intended on purchasing a windshield mount from ebay, but being the cheap bastard that I am, I decided to look online for a DIY solution. Well, seems I'm not the only cheap bastard out there, and there are many plans and configurations for DIY mounting tablets.

After spending time looking at the many DIY solutions, I decided on a simple one of tying string around the air vents and let the tablet, in its case, hang there snug. Watch the video for what is the easiest/cheapest solution:

Well, I tried the string idea, and it did work. Problem was that my tablet sits over the radio, and with the string, there was enough play for the tablet to knock into the On/Off/Volume knob turning the system off when hitting the slightest bump. It also pressed against the knob enough to prevent me from being able to adjust the volume via the steering wheel controls. So I required something that pushed the weight of the tablet away from the console....well, I just so happened to have had a piece of 10AWG copper wire left over from my antenna building stage. I ended up looping hooks on the ends, to hook into the air vents, and bent the wire appropriately for the tablet cover to fold around. The wire is sturdy enough to hold the tablet away from the radio to boot.

The other nice thing is that I can easily remove my makeshift mount if required, and no one would know it even existed.

Now I had to integrate the tablet to the car audio. I was hoping that I would be able to connect the tablet to the car via bluetooth. On its own, this works fine. Problem is that the car can only have one Bluetooth device connected at a time. I can register multiple devices, but only one can be connected/communicated too. Meaning that when the tablet is connected, my cell phone can't be, and vise-versa when the phone is connected. To me, the phone is more important to make a wireless connection, so that took precedence.

I then attempted to connect the tablet via USB (car offers this sort of connection), but it wouldn't connect. I think it's either Samsung or Android not allowing this sort of streaming connection unless the other end is recognized as a computer (guess then it could be the car's firmware). So I can only charge from the USB dock...and even then, that is a hassle, because by default, the tablet wants to connect via USB as a media device, since the connection isn't just a dumb power connection, also the dock is limited to 500mA...just a trickle charge for the tablet.

The only other option is to connect the 3.5mm stereo jack to the cars AUX line-in. This works fine except for when a call is made, or comes in, the system only mutes, whereas when media devices are connected via Bluetooth, the player is actually paused until the end of the phone call. So in came Tasker to perform the simple task of pausing the media player while a call is made, then resume when the call ends.

Luckily the Android devices (both phone and tablet) can have multiple devices connected and communicating via Bluetooth at the same time. So I have the phone connected to the car stereo, the tablet connected to the OBDII Bluetooth module, communicating via Torquer, and both connected to each other and communicating via Tablet Talk.

The final chapter, which I don't foresee an issue is to bring the Raspberry PI video server/network into the fray, and have the tablet connect to it via WIFI. Concerning this last point, I have actually made this connection, and it too is working very well.

If only the "better half" would allow me to install some amps and subs (or just upgrade the existing speakers)...this RAV4 would just be a rock'in mobile.

So below is a quick video of my "RAVputer" as I'm going to call it.

First video showing how the tablet sits on the mount. I tried to show the SqueePlug Pi in the back, but my phone/camera stopped on me. Will show this in the SqueePlug Pi section later.

*NOV 12th, 2013 UPDATE*

Since the beginning of using the RAVputer, I have made a few changes. First I have dropped aVia and PowerAmp. As good as they are in their individual tasks, I was able to find the app BubbleuPNP, which basically combines both aVia and PowerAmp into one. It's not as pleasing to the eye as PowerAmp, but looks fine, includes an EQ, does cross-fading for gap-less audio. For replacing aVia, BubbleuPNP also will allow streaming from external sources...aka...my SqueezePlug server. Bubble has one huge advantage over aVia...it is capable of playing FLAC files, and other offshoot music file types.

So the aVia startup now starts BubbleuPNP, and the PowerAmp widget was replaced with a BubbleuPNP widget.

The downfall of BubbleuPNP was that I am not able to use the media button widgets anymore, so they were removed. Also as mentioned above, the live wallpaper does not show the artist/track information for BubbleuPNP...so that was turned off in the settings (if updated, I may turn back on in the future). I ended up shrinking the Torque start icon down, and moved a WIFI connection widget over the that page. So now everything is accessible from one screen, instead of flipping between two.

New Main screen

BubbleuPnP screen. Bubble replaces both PowerAmp and aVia

Audioglow visual screen. This screen is accessed anytime the HOME button is double pressed. I was also abke to figure out how to display Artist/Track information via scrobbling.