Tutorial DIY 3D printed Sim Racing Hydraulic pedals SRT

It would be good if you modified this part of the lever. The bolt where the cylinder rod is held collides with that part of the pedal and shortens its travel. I tried to fix it with a dremel but I am afraid that the lever will lose consistency.



That part you would have to make it higher, longer.

I have already put the adapters to the pedal. they are perfect.

Normally, the rod touches it if your pedal is press down too much. Can you show me in which situation the rod touches the top ?
Please note that there is two adapters, one from the throttle pedal, one for the brake pedal.

I have the clutch and the accelerator with the same system and the same thing happens to both. I've had to eat a bit with the dremel but it keeps playing. I thought the top was marked by the master cylinder.

Ok I see.. It wasn't meant to go this far, but it's true that the clutch pedal goes further... I will update the design later.

I help you with the design but I have not touched any of the 3d programs. only skechup 8

@Lebois, there is a problem that I cannot solve. Soon after you press the brake pedal, the car brakes a lot. I have touched the minbrake and maxbrake rates but cannot reduce the sensitivity of the pedal. And if I hit the top 100% of the brake, the car stops braking.

You should try the debug mode. Please put :
#define VERBOSE_MODE //allow to tune min and max
instead of
//#define VERBOSE_MODE //allow to tune min and max
and open the arduino monitor, it will show you the raw values, and you will probably be able to find out the problem.

I show you video. Here you will see that I begin to press the brake progressively. When it is almost 100% pressure it stops sending signal. Then I start to release the brake little by little and the signal comes back. You can see it on the monitor.



In the second video I show the clutch but it shows a lower value but when pressing the pedal at 100% it continues to send a signal.

hm...it's really strange. Maybe you can show me the exact code you sent ?

Ok, I already found the problem. The problem was with the brake caliper and the pedal travel. The solution that I have put is to place a sergeant tightening the brake caliper so that the piston of the brake caliper has less travel. Now the brake pedal is somewhat softer and has less travel but when you press the brake at 100% it continues to send the signal.

Te estoy enviando el código que puse en el esquema del IDE de arduino. pero de todas formas ya está resuelto. El otro problema es que el freno es demasiado sensible. Voy a pedir un cilindro maestro nuevo y una pinza de 4 pistones. El sistema de frenos que tengo es motocicleta.

// V1.0: ajout du mode verbose
// V1.1: corrección
// ¡Desactive el modo detallado una vez que haya calibrado los pedales para que funcionen a toda velocidad!
// comenta para deshabilitar || Mettre en commentaire pour désactiver

#define USE_ACCEL
#define USE_BRAKE
#define USE_CLUTCH
// # define VERBOSE_MODE // permite sintonizar min y max

int AcceleratorPin = A0;
int BrakePin = A1;
int ClutchPin = A2;

int minAccelerator = 210;
int maxAccelerator = 595;
int minBrake = 200;
int maxBrake = 700;
int minClutch = 0;
int maxClutch = 400;

int lastAcceleratorState;
int lastBrakeState;
int lastClutchState;
int currentAcceleratorState;
int currentBrakeState;
int currentClutchState;

#include "Joystick.h"
Joystick_ Joystick (JOYSTICK_DEFAULT_REPORT_ID,
JOYSTICK_TYPE_MULTI_AXIS, 4, 0,
verdadero, falso, falso, falso, falso, falso,
falso, falso, verdadero, verdadero, falso);

configuración vacía () {
#ifdef VERBOSE_MODE
Serial.begin (9600);
Serial.println ("Modo detallado activado");
#terminara si

Joystick.setXAxisRange (minClutch, maxClutch);
Joystick.setAcceleratorRange (minAccelerator, maxAccelerator);
Joystick.setBrakeRange (minBrake, maxBrake);
Joystick.begin ();
lastAcceleratorState = analogRead (AcceleratorPin);
lastBrakeState = analogRead (BrakePin);
lastClutchState = analogRead (ClutchPin);
retraso (1000); // retardo de seguridad para flashear el código
}

bucle vacío () {






#ifdef USE_ACCEL

int currentAcceleratorState = analogRead (AcceleratorPin);

if (currentAcceleratorState! = lastAcceleratorState)
{
Joystick.setAccelerator (currentAcceleratorState);
lastAcceleratorState = currentAcceleratorState;
}
#ifdef VERBOSE_MODE
Serial.println ("aceleración");
Serial.println (currentAcceleratorState);
delay(500);
#endif
#endif

#ifdef USE_BRAKE
int currentBrakeState = analogRead(BrakePin);
if (currentBrakeState != lastBrakeState)
{
Joystick.setBrake(currentBrakeState);
lastBrakeState = currentBrakeState;
}
#ifdef VERBOSE_MODE
Serial.println("frein ");
Serial.println(currentBrakeState);
delay(500);
#endif
#endif

#ifdef USE_CLUTCH
int currentClutchState = analogRead(ClutchPin);
if (currentClutchState != lastClutchState)
{
Joystick.setXAxis(currentClutchState);
lastClutchState = currentClutchState;
}
#ifdef VERBOSE_MODE
Serial.println("embrayage ");
Serial.println(currentClutchState);
delay(500);
#endif
#endif

delay(10);

hm...quite strange...did you print the right part to put in the caliper ?

the truth is that the calppier is not correct.

I have placed the correct calppier but it continues to happen, I put the previous calppier with a sergeant and the problem is solved, but the pedal travel shortens and softens.

Hello Lebois! I found this project last night and it is excellent as is your engineering and printing.

I started printing the in ABS I hope that the shrinkage does not have too much of an effect.

Which size diameter master cylinder do you have? how much travel does your pedal have? I am looking for maybe 2-3cm of travel.

It sounds like you are over extending the brake caliper making the pressure drop back down. This is why the fake brake disk is needed (to stop the pistons extending more than designed) or in your case the clamp.

However this should be acompanied with the brake caliper leaking and not retracting well. Do you have any leaks? Liquid may be collecting in the piston dust seals.

Unless you are bottoming out the brake master cylinder before the pistons extend and become unseated. Then the pressure could drop to 0 as the seals "hold" the pistons out. The seals function aside from sealing is also to help retract the brake caliper pistons.

The travel of the pedal will be dependent on the ratio of master cylinder (brake pedal) piston area (diameter) to brake caliper piston area (the total of the caliper diameters). The smaller the ratio the more travel you will get.

It is also dependent on how far the brake caliper pistons can extend (the more they extend the more pedal travel).

To a lesser extent it is based on design (although the lever arm is important) and flex of parts, including the brake line and caliper.

Brake feel will depend on all of the flex in the system. This includes the pedal, pedal mounting, hydraulic fluid compresability, flex of the caliper, and lastly the hardness of the "brake disc".

A rubber "brake disc" will give a different pedal feel than a metal one.

You have been extended and explained in detail.

Now that you mention it, I have looked at the brake caliper and around the brake caliper piston if there is a slight brake fluid leak. Anyway I have ordered a 4 piston caliper.


With the relation to the pedal travel. Ask professionals and they have told me that a 0.625 or 0.75 master cylinder has the same stroke but in what is different is that the 0.75 is harder than the 0.625

BTW I am Spanish so if you want you can msg me in Spanish.

You will still need the fake brake disc with the 4 piston caliper to prevent the over extension. I would do this 1st to prevent any damage to the pistons/seals.

The pedal travel portion is wrong, for the same brake caliper a different diameter master cylinder will have a different stroke and hardness.

This is simple math/geometry. A .625 MC displaces 195.7cc per mm of piston displacement, a .75 MC 285.0cc per mm of piston displacement. This is almost 50% more displacement for the .75 MC which correspondingly should reduce the travel by almost 50%.

When creating the same braking pressure with both MCs the same amount of work (W=FxD) must be done.
The .75MC will travel a shorter distance (D) than the .625MC, using the work equation the force (F) required for the .75MC must necessarilly be higher. In other words the pedal becomes harder.

Whatever pro's you talked to are not engineers, when changing only the MC diameter it is impossible that the pedal becomes harder without a corresponding shortening of the travel.

MC piston diameter/area: Brake piston total diameter/area = MC travel:Brake piston travel = MC pressure:Brake piston pressure. When everything else stays the same.

This is the "simple" truth and ignores any dynamic conditions but I think the effects there are very small and insignificant.

hydraulic fluid compresability

How the heck the fluid can be compressible?)

Hi guys ! Sorry I don't have much time this times because a lot of work and personnal project + working on DIY projects (pedals, actuators gearboxes), so I will answer shortly :

The pedal travel should be quite short, but mostly depends on the quality of the bleeding.
The brake calipers don't impact the feeling that much (I tried the three of them, but the bleeding has more impact on the feeling than the caliper).
Finally, you can preload the system so that you control the travel.

Changing the piston diameter changes the stroke and hardness. I am using the 0.7" from aliexpress with no trouble so far.

About compression, I don't know if brake oil is not compressible at all, or just a little little bit. I guess that the brake hose does. But what is sure is that this system perfecty fakes a real system.

I am really glad to offer people the possibility to build their own unique hydraulic pedals, and I really appreciate to see that people are interested by it. Also, people gives me feedback that helps me to improve this project so much