Raspberry Pi - Carputer Build

Have a 2012 DCLB WT model and originally wanted to add a backup camera, nav, and hands-free. Things quickly snowballed. Searching shows that something like this hasn't been done on this forum so I'm letting you guys know of another HU option.

Disclaimer - way more work than it looks. Much easier to use a suction cup with your phone or tablet.

Open Dash (no longer Open Auto Pro) is a software for Raspberry Pi, not a new OS. You get all of the desired in-car features like Android Auto, BT, OBD-II, etc., but you still have a full-fledged Linux distro with a ton of GPIOs. The hardware and software side are really up to you and what you want to make of it.

Basic rundown of my setup:

• Gut interior of OEM double DIN and hack the hell out of the enclosure
• Print dash bezel to magnetically hold the 7" touchscreen
• Sheet steel to make a 'stack' which holds all of the hardware (timer relay, relay, buck converter, control circuit from protoboard, video grabber,
  $19 M.2 NVMe SSD Enclosure, USB 3.1 Gen 2 (10 Gbps) to NVMe PCI-E M.2 SSD Case Support UASP for NVMe SSD Size 2230/2242/2260/2280(up to 2TB)
  M.2 NVMe, powered USB hub, and some buss bars)
• Make a bunch of wiring harnesses
• Dash insert near gauge cluster with encoders (volume/mute and screen brightness/blanking) and latching pushbuttons for upcoming fogs and rear lights
• Latching pushbuttons below HVAC for backup camera, audio amp, night mode, and a 5V system interrupt

Since I was already this deep, I swapped the gauge cluster and HVAC LEDs to white and made the needles red. Nothing new there, but I'll echo everyone else, really gives ya the fizz.

There are a lot of specifics I could get into, so if you have any questions, just let me know.

 

Care to share the bulb size and difficulty of changing out the ugly orange dash bulbs?

 

The cluster and HVAC are easy. They are well designed snap-fit assemblies and the boards are big. These take SMD 3528s. Buy (100) packs on Amazon of whatever color(s) you want to go with. Using a chisel tip on the solder gun and a pair of tweezers, you heat up one side and pry it upwards. Heat the other side and lift off. I put a small dab of new solder onto the PCB pads and reapplied the new LEDs.

The 4WD knob takes SMD 3014 and those are a pain in the ass because they're so small. Same process as above, but I found that pre-applying solder to the LED before applying to the board worked better. You'll burn through a bunch of these learning the technique. Fortunately, they also come in (100) packs. I had some additional practice when making the encoder light pipes since I used the 3014s on those as well.

Haven't taken apart all of the other controls yet. From past posts it looks like they're 5mm diodes. Not currently planning on swapping those because they're mostly out of sight and I'm tired of working on this project for now.

All of the above assumes you have an actual solder station. The cheap, garbage guns won't cut it here.

 

Thanks for posting. This along with software like openpilot is exciting to see.

 

Hadn't heard of that project before and it looks great. Has me picturing encoded motors all over to overcome the lack of TSS.

 

You missed my favorite part: I love the mic location to just above the steering wheel...it feels like that would be a good spot somewhat insulated from a lot of the potential cabin noises (vents, windows, etc.). Did you print the housing for that? What kind of mic is it?

 

Geezus. And I was worried about installing my drivers side grab handle. Your setup looks badass.

 

That's exactly why I put it there, and the fact that there is a removable insert on top of the steering column shroud which gives a clean wire pass-through. It's a cheap lavalier mic from Amazon. Took a few iterations to get the print to function correctly. Here's a CAD shot to give you an idea:

 

Very nice. So, does the housing actually clip in place there with the tabs on the bottom? I'll have to take a look at mine later today, it might be something to consider.

What is the reasoning for the holes in the side of the housing?

 

If you take yours out you'll understand the clips and shroud base. This is now easy to squeeze and remove but stays locked in. Lavalier mics are omnidirectional. Side ports are for the radial mics. Not sure if they're necessary but my thought was if my wife was with we could both be talking even though she's in the passenger seat.

 

Ah...makes sense. I'll have to take a peek at my mic (Kenwood that came with the HU). I didn't notice anything other than the obvious input on the front...but I honestly haven't looked that closely!

 

Awesome project! Way more ambitious than I'd ever be for something like this, just wanted to give you props for figuring all of it out.

 

Should probably link to another post as the functionality is now incorporated into this project. Have done an in-line speed correction to account for larger tires. https://www.tundras.com/threads/hypertech-or-similar-speed-calibrator-operation.103804/

 

mad props john to your ambitious undertaking brother!

 

Wow! Amazing congratulations!

 

*All of this work makes you better appreciate the features of newer vehicles*

V02 is finally underway. The hand soldered proto-board couldn't quite survive in the cabin as a short eventually happened and the buttons'/encoders' illumination went down. Also, V01 was so big and clunky that it was nearly impossible to fit within the double DIN and dash 'pocket.' It served its purpose to show what was possible and how it needed to be improved. V02 will have a machined PCB with a miniaturized layout. This should make everything easy to access and way more robust. It'll still use the 7" touch screen and currently printed bezel. Couple things which are changing:

• Going to try Open Dash in hopes of ditching Open Auto Pro
• Make the backup cam automatic with reverse gear as well as the anytime button (this turned out to be extremely beneficial)
• Implement the option for software control of the eventual front and rear auxiliary lighting (for instance - turn the front aux on with highs and turn rear aux on with reverse gear)
• Make this board be a carrier for the dual channel CAN card with the four channel DPST relay built-in so wiring is easier

You can check out the CAD, mock of PCB, and schematic. Already planning V03, but assuming this one works well, it'll be quite a while before I get started on it.

 

Nice!

 

Made the board...and it didn't work. Learned an important lesson: hand soldered components NEED thermal relief around their pads. Redid the layout with some optimization and copper pours. Currently making this next rev.

 

Can you give more specifics on the cluster gauge swap.. not a fan of the orange myself

 

There's another thread here about putting in the Optitron gauges if that's what you're asking. I used my original cluster and swapped the LEDs. Post #3 was my summary on needed components and general how-to. Hope that helps.

 

Oof.

You'll get it man! Too damn cool.

 

Dang near artwork.

Another lesson learned: follow the instructions on the side of the bottle. Electroless tin plating really needs 7+mins. Had to take everything off of this board because the solder still wouldn't suck down. Super relieved to say this board is working exactly as it should. Next up is swapping software.

 

Is that a stick of RAM I see?

 

$19 M.2 NVMe SSD Enclosure, USB 3.1 Gen 2 (10 Gbps) to NVMe PCI-E M.2 SSD Case Support UASP for NVMe SSD Size 2230/2242/2260/2280(up to 2TB)

M.2 NVMe drive in a USB converter. Trying to get a bit of snap out of the OS by ditching the typical SD card. That Pi has 4GB of RAM and is enough for what it does. There are 8GB versions, too.

 

How much storage in that NVMe?

 

Smallest I could get - 128GB. Really just wanted those fast IO speeds. At that time I didn't have the quad DPST relay IC, so was a bit hellbent on improving boot time (it didn't improve it).

Also, I don't store anything locally on any device. All files/media live on the NAS. If out, I grab through VPN/Plex, or we'll just stream.

 

v3 is well underway. There were issues with v2 and I'm adding a lot more functionality, and modularity, into this go-round. I'll be overlaying a separate RS-485 network for my external stuff. This means I can add microcontroller modules wherever they're needed. The first module will be to interface with a TST TPMS system for our camper and grabbing rear diff temps.

Here is the main IO v3 board. Fused input, LM555 timer for 5V output, a separate relay for RPi power, plug for three expansion modules, plug for four camera feeds, two plugs for truck params and CAN interception, and some 12V and 5V power supplies. The output has the 24p plug for feeding the RPi and a 6p for the dash insert module.

 

Really stoked on how the new dash insert is looking. Put the screen at 5deg towards the driver and recessed it 15mm to hopefully minimize sun glare. Also offset the light pipes to the outside because it looks cool and will be a lot easier to setup the surface mount diodes on the PCB. This arrangement will remove all of the buttons which are next to the cluster and below the HVAC controls.

 

Learned a lesson: when messing with the CAN bus use OEM contacts. They're likely TE AMP 025/040.

DO NOT USE DUPONT

Have always had an intermittent CEL where I'd drop comm with the cluster for a fraction of a second. My assumption was the RPi couldn't keep up with the multi-threaded script while performing other tasks. When I removed the RPi and it happened again, I figured my "perfectly calibrated 120ohm wire pairs" (AKA just randomly twisted 24AWG stuck in loom) was the culprit as I had left that hanging out of the dash for a week. Was completely shocked when I removed everything, plugged the Dupont connectors back in, heat shrunk them, and got the CEL again.

Turns out Duponts can't support anything greater than a few hundred KHz. There are different baud rates for CAN but the one my truck runs at is 500KHz. Patched this point up and haven't had the CEL return.