This project is something i was planning to finish for quite sometime , its not a carputer since it doesn`t have any connectivity witht the car`s CAN port or gps and other features a carputer must have , its just a media player running Kodi with some red skin
Its based on a raspberry pi 3 , a 5 inch waveshare lcd ,without using the touchscreen , an IR receiver and a simple IR remote , some passives for turning on and off a small cooling fan (its too hot in the car) and the sound comes out from an ancient usb soundbaster from creative that was laying in a drawer for years.
At the begining of this project i was trying to figure out where should i put the lcd. I knew from the begining that i dont like bright touchscreens on my face while driving so i needed to be placed somewhere lower than my face near the stereo and also i would need a remote to change the tracks . I cannot thing anything more dangerous and annoying than trying to change tracks using a chinese resistive lcd with tiny characters while driving..
So i ve started out by cutting out some cartboard and some balsa wood to create a temporary frame for the screen.I `ve found the ideal place to put the whole thing but as it turns out i SUCK big time taking measures and making templates from carboard.
Besides the bad template , it would be extremely difficult for me to build a final version that wasnt just garbage. I wanted to build the frame some kind of steel sheet so it would be strong and durable but after i made a whole version of the thing i`ve realised it wouldnt fit as good as i liked.
So i`ve ended up with a complete unit that didnt quite fit the space i had because of some funny angles on the dashboard the screen would be more upright that it should be in order to be readable , also i was worried about heating issues and i added a fan that made the unit larger and more upright
I had to ditch the whole idea of the solid device design and split it in two main parts..the screen and the main unit.
This was easier said than done…
The first and more obvious problem was the screen. This touchscreen was designed to be hooked directly on the raspberry pi gpio pins in order to be powered , sense the touchscreen and start the device , the video signal was from the hdmi. Finding the power pins was extremely easy but as it turns out the pi must first boot at a point and then turn the power to the screen on.
That sucked because for some time i couldnt decide what to do with this problem
I knew that there must be some hack i could do on the lcd directly but you know what? I had enough with the never ending search so ive just used a relay and a random salvaged transistor from my parts drawer witch was controled by a gpio command on rc.local to power the lcd
Another thing to control was the screaming fan. For this ive used another relay a transistor and found a simple script that measures the cpu temperature range to turn it on or off.
Ok everything was ok and ready to be placed in the box. Soldered directly the sound card , a small interface board that is connected on the gpio containing the relay that powers the lcd and some connectors , and finaly a small psu board that also has the relay for the cooling fan
cutting the boxes both for the main unit and the lcd was very messy and time wasting process , and once again , the final result was not to be presented in a beauty contest hehe
Placing it in the car was an easy task , just hooked it in the aux in of the car stereo . Using it is .. not as easy as i liked…and its not that it doesnt perform well..Everything runs smoothly , no lagging no stalling
Its the positioning and the quality of the screen that is not very bright , its small so you have to stop if you want to change album , but i just make a playlist beforehand and thats it.
Anywayz , it was a nice project that i use everyday for the last year