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Work in progress needs some feedback.

I bought an Ardunio Mega ADK board with the idea that it would be my master controller for my EV project.

I was able to program the ardunio board to commutate the two brushless motors inside the Prius Transaxle via the Prius inverter. I haven't fully optimized my max torque per Amp control method yet but the motors are spinning nicely on the bench. I have some to learn about how to generate the optimal torque vector with these types of motors but good enough for now.

I also have the ardunio board timing pulses coming from my daisy chain of cell board circuits that I built representing each cell voltage for my planned battery management system. It is working but also in a bit of proof of concept state.

Now I want to get to work on my user interface. I am very unsure about the pitfalls or challenges this will have so I am soliciting some direction. It is my understanding that my Ardunio ADK board will act as the USB host (whatever that means) connected via usb cable to the Android tablet in accessory mode(?) . I assume that it will be able to power and charge my tablet when connected.

Which tablet to buy? What Android version is preferred or needed for this type of project? Any hardware exceptions? Good source for example code for Android graphical interface and Ardunio usb communications (specifically for this ADK model)? Basically where to start with my GUI development is my situation at this point. I am researching but I have quite a bit of learning curve ahead. I will start with "Hello World" and then build up but I would like to avoid building in limitations right from the start with poor hardware or firmware selections.

I am not an experienced software developer so it is overwhelming with where to start sometimes.

Any suggestions or guidance is appreciated.

Thanks
Jeff
 

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Hello Jeff,

You might want to check Pete's thread here on his Android EV app: http://www.diyelectriccar.com/forums/showthread.php/another-ev-dashboard-46241.html Perhaps he can give you a hand with that. Too bad there aren't many (any?) tables that run MS .Net framework because graphics processing is a lot easier with it. There are also lots of ready made controls you can just load and use.

Can you expand on the Arduino drive of your motor controller? Doesn't the Prius inverter already include the logic to drive the motor? Maybe you don't have the Prius controller but instead are building your own.

JR
 

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Discussion Starter #3
Can you expand on the Arduino drive of your motor controller? Doesn't the Prius inverter already include the logic to drive the motor? Maybe you don't have the Prius controller but instead are building your own.

JR
I do not have the Prius controller. I am building my own motor and battery management controller.

I am using the arduino board to generate the PWM signals for each motor phase. The Prius inverter is just a slave to these individual signals. The inverter houses all the high power electronics. I got the inverter on ebay for $100.

I am a little lost on how to develop the Android Tablet side of things. I want to use a tablet as my user interface for a complete monitor and control of all my systems. It is supposed to communicate to my arduino board via usb. I seem to be able to hack up the arduino code just fine. I hope the Android programming is also doable for me.

Jeff
 

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If you can hack out some code for arduino you'll be able to get your head around Android.

Sounds like your wanting to use the Android Open Accessories Dev Kit see here http://developer.android.com/guide/topics/usb/adk.html

It actually looks fairly easy to use. The ADK was introduced for 3.1 and has been backported to Android 2.3.4. So you'll need to make sure your tablet supports that version.

I might also support the ADK myself in my Android dashboard project because I'm planning to support a hardware board called IOIO which includes the ADK although its optional.

Good luck

Pete,
 

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you could have a look at "neo freerunner", an open source phone supporting android and a collection of other Linux based systems. A bit ugly but if integrated in the car the original appearance should not be relevant, you can probably remove the shell and just mount the screen wherever you want. It's obviously more of a phone than a tablet, but offers more flexibility.
 

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Discussion Starter #6
If you can hack out some code for arduino you'll be able to get your head around Android.

Sounds like your wanting to use the Android Open Accessories Dev Kit see here http://developer.android.com/guide/topics/usb/adk.html

It actually looks fairly easy to use. The ADK was introduced for 3.1 and has been backported to Android 2.3.4. So you'll need to make sure your tablet supports that version.

I might also support the ADK myself in my Android dashboard project because I'm planning to support a hardware board called IOIO which includes the ADK although its optional.

Good luck

Pete,
I bought a Nextbook Premium 7 for $130. It was advertised with android 2.3 but come to find out it is not the same as 2.3.4 (API 10) that I need for ADK.

I am now researching what my options are but things are clear as mud at the moment. I just want to be able to use the touch screen as my interface for everything I have running off my Arduino.
 

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I think there are lot of us that want the same thing and we're all going about it different ways.
I want a nice big LCD screen that displays all my data. And I want it to have a touch screen, and be easy to interface with. I'm using this:
http://shop.4dsystems.com.au/serial-display-modules/302-0004.html

I have 3 smaller versions of this, the two 2.8 and one 3.2 inch versions. I started playing with them a few months ago. They're really easy to program and communicate with. I'll post a picture of the display I've made and code if anyone wants to see it. I have it communicating with my modified Open Revolt controller and displaying data. They also have speakers and an SD card so it's easy to play wav files when a button is pressed or when any other event happens.
Their free IDE is nice, and with the Visi tool they've added making a nice display is easy.
The touch screen is easy to interface with as well. Only negative thing is floating point isn't supported, but I can work around that.
I plan on working it into the dash so it looks like it belongs. A nice finished look.
 

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Work in progress needs some feedback.

I bought an Ardunio Mega ADK board with the idea that it would be my master controller for my EV project.
are you familar with the IOIO for Android

I am not an experienced software developer so it is overwhelming with where to start sometimes.

Any suggestions or guidance is appreciated.

Thanks
Jeff
Android sits on top of linux. it also supports Java.
here is a Java graphic library I use
 
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