Universal Steering Wheel to USB Controller + More
We've almost finished the Toyota/Scion Steering Wheel to USB controller, but along the way, I discovered many other makes use the same resistive ladder system.
Let's begin by summarizing the work done so far:
First, Version 1.0 of the controller is complete. The product looks like this, connected:
It emulates a HID keyboard and consumer control device. Therefore, no drivers are needed, and it runs on any operating system, and appears as a USB composite device:
It is controllable/reprogrammable via a user-interface, so the device will not become obsolete until the hardware does:
Okay, now onto version 2, which was in development until now. The goal was to reduce the layout size and improve reliability as well as reduce noise on the ADC lines. The design was completed with a LOT of help from blues:
The bill of materials w/o labor and shipping, as well as without the pcb comes out to around 9$ (this hasn't been updated to reflect some cheaper parts, and the mega is a TQFP)
The end cost is about $25 per completed board, shipped. Unfortunately, I would have to purchase about 140 of them, which is quite a bit of investment if there aren't going to be enough people to purchase them.
And that's why we're here. If we can get some help from owners of other car makes to measure the resistor ladders on their steering wheel controllers, we can probably gather more interest to make the controller across a wider array of cars. Not only that, if you ever decide to change makes, this controller would still be useful for you. It might involve a small increase in cost by no more than $5.
I'd like to note that this project is open source (i.e. i'll be releasing the firmware source soon). Also, the end product might actually have a few extra ADC/digital inputs, so it might be able to measure illumination voltage (to control brightness on your monitor) and maybe even give battery status to windows (like a UPS does when you plug it in).
Anyway, if about 50 people are willing to pay for the product as-is now, there'd be no problem in getting it done. Otherwise, we can try to get measurements for other makes. Anyway, that's what the poll is for, so vote =). Thanks!