Modification to replace the stock potentiometers in the G29/G27 pedals with hall sensors
There are two alternative designs in this repo
- modification using the original pot as part of the magnet holder assembly (as show in the above image)
- complete replacement of the original pot with a 3D printed design
Both designs require some additional parts to accompany the 3D model
- 2x 6mm diameter 3mm high magnets
- A1324 hall effect sensor
Over the 70 degrees rotation the pedal rotates the pot axis, the output of the A1324 is very linear. The chart below shows the output of the sensor compares to the output of the pot whilst both are connected in the same pedal:
The next chart shows an XY scatter of the pot vs the hall sensor readings for each sample taken:
The units of each plot are the 10 bit reading of the ADC in a Pro Micro Arduino
The A1324 is rated at 5V, but it was found during testing that it actually works at 3.3V, so it appears to be completely compatible with the G29. There is however another variant, the A1319, which is rated at 3.3V
This design engages with the stock potentiometer, using it as the base of the magnet holder.
There are two alternatives to this design:
- where the sensor leads exit the side of the assembly (mod/stl/side-exit-explode.stl)
- where the sensor leads exit inside the assembly and therefore inside the pedal base (mod/stl/inner-exit-explode.stl)
This completely replaces the stock potentiometer with a 3D printed replacement. The tolerances are pretty tight, but can be relaxed a little with some additional silicone grease or suitable alternative.
If you want to see how things took shape or throw in suggestions, you can find some of the musings on racedepartment: https://www.racedepartment.com/threads/g27-g29-hall-sensor-mod.190696/