Sim Racing - Handbrake v2 / Solid & Easy to build / Arduino

If you are Canadian you might have an old hockey stick & a skateboard in your garage haha.

The photo is actually my version 2 and it is what I'm using right now. I will print and upload V3 when time come. The print is solid and easy to assemble it doesn't take a lot of space it is about 60mm wide it is relatively slim. I'm providing the STL file so feel free to play with it.

I have done some failure test and i believe it is pretty solid. I crank the handbrake and let it go multiple time and nothing break.

***** Hardware *****

1. Old hockey stick.

2. 4x Skateboard bearing 22mm Dia. AMAZON

3. 2x M8x1.25 x 60mm long

4. 1x M8x1.25 x 80mm long

5. 2x M8 nuts

6. I use an old spring pedal for this print. You can also take a different kind ( Make sure it is at least 15mm of inside Dia. AMAZON

7. 1x 75mm Straight Slide Potentiometer A103 10K Ohm Exponential Double Potentiometers for Dimming Tuning AMAZON

8. I use a Raspberry Pie Pico 2W because it is what i had. But you can use an Arduino Pro ( A lot easier with Arduino. AMAZON

9. Soldering kit

10. Wires

11.  Drill

12. 5/16 drill bit or slightly bigger

13. Handsaw to cut the desire length of the hockey stick.

***** Software *****

1. Arduino IDE

To test your Handbrake and see the telemetry use Joy.cpl in your search bar at the bottom. 

***** Print Instruction & Assembly *****

1.  Wall loops - 7

2.  Top Shell layers - 5

3.  Bottom Shell layers - 5

4.  Sparse infill density - 45

5.  Sparse infill pattern - Gyroid

6. Use support

7. You will have to print 2x Bushing that goes at the bottom.
   

***** Arduino Code *****

Because I have a Raspberry Pie and an Exponential Potentiometers it was a little hard to code. If you can buy a Potentiometer that is not Exponential it will make your day a lot easier. Because I had an Exponential Potentiometer I had to remap the whole thing until I got it right. The issue you might encounter is when the handbrake is resting you will have the handbrake engage at 30% or it will only engaging mid way.

If you have an Elegoo Nano it won't work it doesn't support "Joystick".

#include "Adafruit_TinyUSB.h"
uint8_t const desc_hid_report[] = { TUD_HID_REPORT_DESC_GAMEPAD() };
Adafruit_USBD_HID usb_hid(desc_hid_report, sizeof(desc_hid_report), HID_ITF_PROTOCOL_NONE, 2, false);
hid_gamepad_report_t gp;
void setup() {
  Serial.begin(115200);
  analogReadResolution(12); //
  usb_hid.begin();
  pinMode(26, INPUT); 
}
void loop() {
  int rawValue = analogRead(26);
  // --- SHORT THROW CALIBRATION ---
  // 200: Your starting point (0% / Left Border)
  // 1800: Your new "Full Pull" point for 2.5cm travel
  // -127 to 127: The range Windows expects
  long tempValue = map(rawValue, 200, 1800, -127, 127); 
  int8_t finalValue = (int8_t)constrain(tempValue, -127, 127); //
  gp.x = finalValue; 
  if (usb_hid.ready()) {
    usb_hid.sendReport(0, &gp, sizeof(gp));
  }
  // Watch this: If Mapped stays below 127 when you pull fully, 
  // you must LOWER the 1800 in the code above.
  Serial.print("Raw:"); Serial.print(rawValue);
  Serial.print(" | Mapped:"); Serial.println(finalValue);
  delay(10); 
}