Looks like a solid plan.
Looking forward to seeing how it comes along.
Hey guys and gals,
I found a workblog here similiar to the project I'm planning to built in this forum so I decided to share my progress aswell.
My car is a 2010 Opel Corsa D.
Opel is a german manufacturer that belongs to General Motors, so the Corsa is built in different plants around the world and sold under different brands (In case you don't know Opel).
My particular car looks like this: (don't have a picture of my car at the moment)
The Car PC/Carputer I'm going to built is meant to replace the standard radio completely so it'll include an amp.
The Parts list (main components) is as follows: (Links will link to where I bought it, so it might be in german)
- Odroid U3 & 8GB eMMC Unit (Android) & 16GB Micro-SD Card
- Odroid UPS Battery-Pack
- 7" Resistive Touchscreen (no Multitouch, but it'll work with gloves in winter)
- GPS - Bluetooth Module
- 2 Channel Amp
- Active USB Hub
- 92mm Fan
- DC to DC Converter
- some switches, potentiometer and other stuff
Here is a rough layout of how I'm planning to built it:
I'm a bit uber-paranoid when it comes to safety, so I include a fuse box with a fuse for the constant+ and ignition+ (from the cigarette lighter) and also one fuse each for the major components. The ignition also just powers a relay to switch the constant 12V+ ... I don't want my car to burn down.
I use the Odroid Battery to power the unit when the ignition is off. Either for a short while (1 minute or so) or as long as it can (can't decide yet), so the unit is still on when I turn the key again, all the other components will be powered off regardless; I plan to use switches to power the Odroid and the Screen seperately when I don't want to turn the ignition on. (this feature will probably be removed later, but I want this at least for a few weeks, so I can check how the unit performs in the field (by turning the screen back on) without giving the battery power again. This way I can check if shutdown scripts work correctly or not.
Unfortunally I'm still missing some parts like the battery, the USB Hub (both should arrive this week), and the GPS module (3-4 weeks... ordered from China directly). So I can't show anything off yet, so see this as the introduction. (Also, the screen came cracked... already called the vendor, it takes about a week to get a free replacement)
However, I'm going to do a Vlog as well, so I made an Introduction Video (excuse my accent and the sniffing noises, I have a minor cold)
I'll post the next update in a few days (or maybe tomorrow), with an actual image of the actual car I own
Looks like a solid plan.
Looking forward to seeing how it comes along.
Take an advice from me: find a better voltage drop-down module. They ware good at beginning but after a couple of mouths of use they started to make jokes with me. This is my personal experience - hopefully you wont have such.
Good plan thou...
@VolvoCarPC: thanks aswell. Do you have a suggestion for a good DC Converter? I like this one because it's small, however if they are unreliable then it's better to sort them out as early as possible.
Let's continue, first with some real pics of my actual car I took during lunch break.
Also the middle console of my car.
The new Car PC will replace the middle section of it (where the JVC Radio and my cigs are)
Now to the real stuff.
Today I started to extend the size of the new frame with some mesh I had laying around,
I also put some tissue and duct tape on the sharp corners so they don't tear the cables.
I also dry-fitted the new 92mm fan in it and checked that looks kinda right.
Not really pressure optimized but it will be enough to let the air circulate through the unit.
After that I got my test-bench working. The switch is there to simulate the ignition.
Besides the new fan, I also got some other stuff today at a local hardware store.
Then I soldered most of the things around the fuse box and I also got the relay working.
The cables on the right of the fuse box are from top to bottom:
- A switch to switch from the relay to the constant 12V+ for the screen (I decided against a second switch for the Odroid as originally planned)
- Power for the USB Hub; still needs a 12V to 5V converter
- Power for the Screen
- Power for the Odroid; Converted to 5V
- Power for the Amp; Also includes an Ignition wire, because the Amp can switch on and off on it's own based on the Ignition.
- The Relay
The Blue thing on the bottom is a rail for the 0V/Neutral
I made some changes, so I need to update the layout plan. But I'm too lazy for that at the moment and probably do that tomorrow.
The next thing on the to-do list is to actually connect some things to the "power unit" I made today and see how it runs. And I wanna see how fast Android boots on this unit, so I'm going to make a video for the first boot and do a second time also when everything is configured correctly (since the first boot probably takes longer)
I hope the other post I made before, appears before this one... since these are moderated for new users, these seem to take some time to appear (Which is understandable to avoid spam, but slightly irritating)
Just a quick update.
The changed plan:
now only includes one switch for the screen instead of a second one for the odroid, and the Amp is powered differently.
(It also features bigger text ) The plan still does not include Neutral/0V wires.
And for the people that might be interested in the costs of this project, here is a little table. Prices are in Euro and include tax. (also note that these are the prices I paid for it, so they might differ depending on your location and your local dealers)
The "Complete" price includes the stuff I needed for the testbench (and possibly tools) but they are not a direct part of the unit... so probably not that interesting for you guys, but for me.
Another quick update
Got a few new parts like the USB Hub, another DC Converter and some small stuff.
I got the amp connected (found some old speakers to test it) and also the USB Hub and the fan. I'm still waiting for the replacement screen and because my TV broke,
I have no display I can use with an HDMI Port, so I can't test the Odroid yet.
Here are some pictures of the changes I made today:
Oh yeah, and since I did connect the amp, I tried to use this potentiometer I bought, which promised to have A LOT of features...
and features it has, unfortunally after I soldered the stereo volume, the balance control and even the switch that turns the amp off when you turn the poti all the way down...
only then, when I tested it, I realized that the volume control is linear, so it does almost nothing 2/3 the way up and then goes way too fast, way too loud. bummer, but oh well, it only did cost like 50 cents but over an hour of soldering and finding out what all of these pins do... just look at that beautiful waste of time:
I ordered a new one... Stereo 22 Ohm log - that should work, even though it doesn't have all those features, but that doesn't matter.
The next update should be a test boot next week; I can't wait to see how fast this boots up (since I'm using an eMMC unit).
Unless some other interesting parts come along, I have to wait. I'll accept feedback until then
I also did a new video for the vlog...
I later found this article:
And I decided to buy KIM-055L from ebay for like 4 bucks:
It works pretty work - I have been using it for a few months (for a raspberry pi based 3d printing server), and it's still working great. I can always get power efficiency over 97+%, which means there's extremely low heat dissipation. It also has two M2 mounting holes so that you can better mount it. Good value for money.
If you have like a prototyping PCB or something to solder your regulator, I would also recommend the 78SR 2 Amp Series from Murata:
It's a well know manufacturer and the temperature ratting (up to 70C) is good enough for automotive. I always feel reliability is the first priority for car cause the environment condition is harsh (humidity, vibration, etc.) and you don't want to fix things on the road. KIM-055L is a really great product but there's no datasheet or any guarantee. That's why I use 78SR-5/2-C for my own CarPC project.
Just my 2 cents.
Thank you ivanwyc.
I was just going to say that I'm still searching for a good regulator. With your post you helped both of us.
I'm also thankful to moderators ...
Last edited by VolvoCarPC; 10-31-2014 at 10:50 AM.
Thanks ivanwyc; I ordered some of the KIM-055L regulators from china, will take some time for them to arrive. Until them the cheap ones will suffice.
Quick update to let you guys know I'm still alive
I got most of the parts:
new switches, new potentiometer, the GPS-Bluetooth module already arrived from china, 4 pole 3,5mm jack for audio out and microphone in and some extra stuff.
however, I'm still waiting for the odroid battery, the microphone,...
... and the screen, which troubles me the most.
The first one I received cracked during transport, so I did send it back to the vendor. I was hoping to get a replacement soon enough and then my vendor called me. The screen isn't in stock anymore but they ordered new ones which will most likely take 2-3 weeks maybe longer.
I don't want to wait like a month or so, so I researched for a replacement screen which shouldn't be too expensive (if possible in the ballpark of the other one or up to about 100€). And the result was either inferior or WAY to expensive (200 bucks and more). I did however find something interesting... a screen of a Nexus 7 (and other tablet screens) which should fit nicely but I'm not sure how to connect said screens so I get it connected to the HDMI out and also get the Touchscreen working. Maybe some of you can help me, either some info how to connect a normal tablet screen or point out a different screen which would work and fit into the the frame I have. (I'm also fine with a resistive touchscreen because that work with gloves in winter) The complete screen should not be bigger than 189x111mm (the height is the most crucial part).
Until then, I can't do much.