Sim Brake Thoughts

[kikie]

*starts pondering if the next advancement is sim brake systems will be to rotate one (real car) brake disc according to game telemetry readouts, and use a (real car) brake caliber and hydraulic system to apply brake pressure on a real rotating disc. Though you might want to enclose the disc (due to dust) and add some ventilation.

Interesting read here though. Shame I didn't saw it before.

Yep, but the problem remains. It's the signal output (voltage) read by the sim that remains the same. Whether you use a complete brake system of a real car or not.

Using what you suggested or using a load cell/pressure transducer does not change the final result (signal read by the sim).

 

[Caz]

*starts pondering if the next advancement is sim brake systems will be to rotate one (real car) brake disc according to game telemetry readouts, and use a (real car) brake caliber and hydraulic system to apply brake pressure on a real rotating disc. Though you might want to enclose the disc (due to dust) and add some ventilation.

Interesting read here though. Shame I didn't saw it before.

I had toyed with this idea about a year ago. I was pulling brake parts off my old race kart to put together a hydrolic unit for the csp stand i was developing.

My thoughts were to have the disc run by an electric motor that was run by the games speedometer. But i am an electronic caveman.

 

[LogiForce]

Yep, but the problem remains. It's the signal output (voltage) read by the sim that remains the same. Whether you use a complete brake system of a real car or not.

Using what you suggested or using a load cell/pressure transducer does not change the final result (signal read by the sim).

How do you think a computer works? It can't be done differently for technical reasons. So the grinding about 'only voltage differences are read out and send to the game' is totally useless.
As noted the communication in between different computer components and sensory systems will simply never change. The only thing we could focus on is changing the resolution up from 12-bit to 64-bit (for an indiotic example). Cause what happens is that the increments from 0 to 5v will be smaller, which makes the rise and fall smoother (more analog) in feel.
For example:
When using a sensor system to determine the rotation of a steering wheel, you could go for 18-bit as this would give you almost 1000 steps per degree of rotation. Which means that you would never be able to feel the difference between such a system or a car (or even higher resolution).
I am sure this will be the same for pedals. So keep in mind that a higher solution is better, but beyond a point you wouldn't notice any difference anyway.

The rest of any build, wheel or pedals comes down to feel no matter how you look at it.

I had toyed with this idea about a year ago. I was pulling brake parts off my old race kart to put together a hydrolic unit for the csp stand i was developing.

My thoughts were to have the disc run by an electric motor that was run by the games speedometer. But i am an electronic caveman.

This was just a silly idea that never works, because...

The only issue with this system is that you can't get the lockup point right at all.
Cause you'd need to either calibrate brake pressure, motor torque to the car you're running at the time. And even then the weight differences would make it nearly impossible to get the correct lockup point right.
Also turning it around and send a lockup signal from a rotation sensor on the brake disc to the game won't help either. Again car weight transfer will determine the torque on a car's brake disc. So which wheel will you emulate?

Of course you could use 4 of these, but what motors to use? There are some very heavy cars out there with heavy brakes. Either you'd need to scale the torque figures and brake pressure from the calibers down, or use extremely big motors. Like something from an electric car like a Prius. Which would become a bit idiotic and would mean a painful rise in the electric bill.

So yeah, wild idea but impossible to properly implement.

 

[Mayaman]

Here's my .02 on the situation.

I currently have the following.

Clubsport V2 with CST super brake spring.
Clubsport V1 with stock load sensor.
G27 pedals stock.
G27 pedals with Century springs in the gas and clutch and a Perfect Pedal.

Firstly I have to say that Pilmat has hit it on the head about how the pedals transfer their signals, no arguing that. What I will say though is that depending on the person, you'll get a better feel for that travel and a better feel for braking depending on how you race, what type of person you are, and how important feedback is to you.

With my stock G27 pedals I can be quick, but I feel detached from the sim. I don't race in socks or bare feet, never have. With my racing moccasins from Sparco the stock G27 pedals really feel toy like, kills the immersion for me and give me zero "Feel" for braking. Nice set of pedals but definitely for socks or bare feet IMO.

My G27 with Century Spring springs in the gas and clutch and a Perfect Pedal are my second favorite set of pedals. I love the modded springs for feel with shoes on. While the clutch isn't realistic in its motion, with shoes it feel much better on actuation to have a much stiffer spring *non progressive of course for clutch* The perfect Pedal brake IMO is pretty brilliant. Really good feedback on travel with shoes on, and I can tell when I'm reaching the threshold right before lockup. Worth every penny IMO. I also have this set out of its plastic housing and mounted on a Sim Sport 80/20 pedal mount made just for these pedals. Also I have extended pedal arms. The set just feels robust, more realistic underfoot, and more suited to hard driving. YMMV.

Clubsports in their stock original setup are my least favorite pedals. I hate the original load cell, its just to weak feeling, the travel sucks, the gas pedal spring is horrible and the clutch is basically just a flappy tongue. Blah, don't like them at all. Never modded them and haven't used them in two years.

Now on to my favorite set of pedals ever. The Clubsport V2s. My set isn't a normal set though. I have replaced the stock springs with Century Springs custom springs on the clutch and gas. A little more resistance of the gas and clutch, non progressive. Feels great. But my biggest change was the the brake where I removed that garbage spring they had on it and replaced it with the super brake progressive spring from the CST F1 pedals. The braking is firm, progressive and great for when you're wearing shoes or moccasins. Definitely cannot use this set without shoes, your feet will cry. I find that with this set I tend to brake late less and take less chances. It gives me a better feel to the pedal and allows me to actually reduce lock up. This is key to braking well. Steady, smooth braking. The Clubsport V2 clutch is also BRILLIANT, and with the new spring even more so. Its powerful and feels real.

And to the point of my post. While the pedals all communicate in the same way, its the feeling you get from the pedals and the feedback from mechanical movement that IMO makes you a better driver. Its why we use Wheels with force feedback, to send us messages on what our car is doing on the track. At least for me, the evolution of my pedals has made me a better driver and everything more fun to boot. YMMV.

 

[kikie]

How do you think a computer works? It can't be done differently for technical reasons. So the grinding about 'only voltage differences are read out and send to the game' is totally useless.
As noted the communication in between different computer components and sensory systems will simply never change. The only thing we could focus on is changing the resolution up from 12-bit to 64-bit (for an indiotic example). Cause what happens is that the increments from 0 to 5v will be smaller, which makes the rise and fall smoother (more analog) in feel.
For example:
When using a sensor system to determine the rotation of a steering wheel, you could go for 18-bit as this would give you almost 1000 steps per degree of rotation. Which means that you would never be able to feel the difference between such a system or a car (or even higher resolution).
I am sure this will be the same for pedals. So keep in mind that a higher solution is better, but beyond a point you wouldn't notice any difference anyway.

The rest of any build, wheel or pedals comes down to feel no matter how you look at it.





*snip*

The whole point of this thread is that whatever brake system you use whether it's a hydraulic system, load cell, potmeters, the game (sim) will always read a voltage, even with your idea, untill the game programmers make a radical change and program the game in such a way that it (the sim) reads the pressure of the brake pedal system instead of a voltage signal. But you said that this probably can't be done due to technical reasons. Right?

So, putting a rotating brake disk between the caliper or a load cell doesn't matter, the signal read by the game is still the same. Eventough your brake system can read the data from the game, the information send by the brake system back to the game (sim) is still an electric signal.
It's all about the feel and muscle memory.

Unless I'm missing the point, that's how I see it but I can be completely and utterly wrong though.

If I'm wrong, I'll have to start reading this thread all over again because that means that I still don't get it.
So, in case that I'm wrong, explain it to me be because I'm intrigued.

 

[Jet Badger]

Yes, a computer can only read voltage. But that's where pressure transducers/loadcells/pots come in - they convert force/pressure/position into electronic signals that computers can compute. The creators and programmers of racing sims spend hundreds of hours to make sure the in-game car responds to the input just like a real car, and that is no problem for us.
The initial idea of this thread was not actually about how a computer sees the input, but what is the best way to make a brake pedal that would be easy and natural to modulate (focusing on the hardware part of sim racing, not the software). Pilmat put our attention on whether you use a hydro/loadcell/pot setup you can acheive similar feel under your foot and that the worshiped loadcells and hydraulics are not the only way to produce a quality realistic brake pedal.

- Hydraulic setup measures force using a linear sensor and has a realistic dampened feel. Worshiped on iRacing forums, costs around 26 fortunes.
Well, it's a good option but the cost is astronomical if you use other than refurbished/junkyard parts.

- Loadcell also measures force in a linear manner but setting it up to make the pedal feel realistic is a bit more hassle. Is kind of affordable.
IMO CSP V2 is the best design that's using a lc, though there's still things I'd do differently.

- Potmeters/hall sensors. If you want a realistic brake using these, you'll need some creativity and ingenuity. It's not impossible but is a bit more complicated than with a loadcell. Really cheap in comparison.
MrBasher's skateboard bushings mod to T500RS pedals is probably the best example of this to-date.

IMO Hydraulics' feel would probably be rated 9 (from 1 to 10) but the price is worth 3, so that's an overall of 6. If one would make a pedal using pots that would have the feel of 7-8 and the price of 10, it would be a pedal with 8.5-9 overall. That makes it a better pedal in my book.

Ofcourse for people who take the pricetag out of the equasion, the expensive set makes a better pedal.

Short version: The computer interface isn't the problem. Our focus is on the feel of the brake pedal.

 

[kikie]

The whole point of this thread is that whatever brake system you use whether it's a hydraulic system, load cell, potmeters, the game (sim) will always read a voltage, even with your idea, untill the game programmers make a radical change and program the game in such a way that it (the sim) reads the pressure of the brake pedal system instead of a voltage signal. But you said that this probably can't be done due to technical reasons. Right?

So, putting a rotating brake disk between the caliper or a load cell doesn't matter, the signal read by the game is still the same. Eventough your brake system can read the data from the game, the information send by the brake system back to the game (sim) is still an electric signal.
It's all about the feel and muscle memory.

Unless I'm missing the point, that's how I see it but I can be completely and utterly wrong though.

If I'm wrong, I'll have to start reading this thread all over again because that means that I still don't get it.
So, in case that I'm wrong, explain it to me be because I'm intrigued.

Yes, a computer can only read voltage. But that's where pressure transducers/loadcells/pots come in - they convert force/pressure/position into electronic signals that computers can compute. The creators and programmers of racing sims spend hundreds of hours to make sure the in-game car responds to the input just like a real car, and that is no problem for us.
The initial idea of this thread was not actually about how a computer sees the input, but what is the best way to make a brake pedal that would be easy and natural to modulate (focusing on the hardware part of sim racing, not the software). Pilmat put our attention on whether you use a hydro/loadcell/pot setup you can acheive similar feel under your foot and that the worshiped loadcells and hydraulics are not the only way to produce a quality realistic brake pedal.

- Hydraulic setup measures force using a linear sensor and has a realistic dampened feel. Worshiped on iRacing forums, costs around 26 fortunes.
Well, it's a good option but the cost is astronomical if you use other than refurbished/junkyard parts.

- Loadcell also measures force in a linear manner but setting it up to make the pedal feel realistic is a bit more hassle. Is kind of affordable.
IMO CSP V2 is the best design that's using a lc, though there's still things I'd do differently.

- Potmeters/hall sensors. If you want a realistic brake using these, you'll need some creativity and ingenuity. It's not impossible but is a bit more complicated than with a loadcell. Really cheap in comparison.
MrBasher's skateboard bushings mod to T500RS pedals is probably the best example of this to-date.

IMO Hydraulics' feel would probably be rated 9 (from 1 to 10) but the price is worth 3, so that's an overall of 6. If one would make a pedal using pots that would have the feel of 7-8 and the price of 10, it would be a pedal with 8.5-9 overall. That makes it a better pedal in my book.

Ofcourse for people who take the pricetag out of the equasion, the expensive set makes a better pedal.

Short version: The computer interface isn't the problem. Our focus is on the feel of the brake pedal.

I also said that!

The voltage input is part of the discussion. Putting a rotating brake disc in the caliper doesn't make the hydraulic brake any better, or worse for that matter. And that's what I was trying to say.

 

[fatkrakr]

The voltage input has nothing to do with how the pedal feels under foot. Thats what this discussion is about, brake feel not brake signal.

 

[kikie]

The voltage input has nothing to do with how the pedal feels under foot. Thats what this discussion is about, brake feel not brake signal.

For the second time that is what I said.

It's all about the feel and muscle memory. Whatever brake pedal system you use, if you can't properly modulate the braking and there is no muscle memory, than you don't have a realistic feel of the pedal.

 

[fatkrakr]

I also said that!

The voltage input is part of the discussion.

So then this is not part of the discussion.

 

[LogiForce]

The whole point of this thread is that whatever brake system you use whether it's a hydraulic system, load cell, potmeters, the game (sim) will always read a voltage, even with your idea, untill the game programmers make a radical change and program the game in such a way that it (the sim) reads the pressure of the brake pedal system instead of a voltage signal. But you said that this probably can't be done due to technical reasons. Right?

So, putting a rotating brake disk between the caliper or a load cell doesn't matter, the signal read by the game is still the same. Eventough your brake system can read the data from the game, the information send by the brake system back to the game (sim) is still an electric signal.
It's all about the feel and muscle memory.

Unless I'm missing the point, that's how I see it but I can be completely and utterly wrong though.

If I'm wrong, I'll have to start reading this thread all over again because that means that I still don't get it.
So, in case that I'm wrong, explain it to me be because I'm intrigued.

First of all If you looked at my post's part that you so conveniently ignored and snipped off in your quote, you will read that the use of real brakes is useless for use because of reasons stated. Besides, it was just an idea/random nonsense I spouted for sillyness' sake.

About the voltage read out and all. What idea do you have to read out the pressure without using electricity, yet hooking it up to a PC (thus electronic equipment)? It can not be done, but if you know how... enlighten us please.

I believe I also noted that the feel is the only thing that can be different (the last sentence in the quote).
Also braking is not only about the feel of the pedal, but also feel in the wheel as well as car/rig movement and tactile vibrations.

 

[mrbasher]

Also braking is not only about the feel of the pedal, but also feel in the wheel as well as car/rig movement and tactile vibrations.

iRacing does an excellent job with this in my opinion... I haven't noticed the effect much in other games.

 

[LogiForce]

iRacing does an excellent job with this in my opinion... I haven't noticed the effect much in other games.

I wouldn't know to be honest as I don't have a motion rig and just a single buttkicker with simvibe.
So yeah, I am talking about the physical need and influence of motion and tactile hardware upon braking performance.

Motion for the diving of the car and simulation of body roll (which is handy under trial braking), which would let you feel the balance of the car. This would in turn aid your body to recognize when to apply certain pressure on the pedals.
Than the tactile can be use for lockup and skidding of tyres. Letting you know where the limit of the tyre is.

I know some will now say "stop talking about motion and tactile, we are talking about pedal feel". But I want to stress that a car decelerating entails more than just the pressure of a brake pedal.

 

[mrbasher]

I don't have any of those things either... I'm talking about the sensations given through the wheel at/near tire lock-up. It's conveyed directly from the sim.

 

[LogiForce]

I don't have any of those things either... I'm talking about the sensations given through the wheel at/near tire lock-up. It's conveyed directly from the sim.

I am not such an iRacing fan. Especially since you need to adjust FFB on a per car basis.
The last time I ran iRacing for a test run was a few weeks ago with the Lotus 79. I wasn't impressed at all.
Actually lately I am not feeling slightly satisfied with any game FFB wise other than pCARS, which makes me feel like a fanboy because of this single preference. I tried every beta and released game to date except Assetto Corsa, and from this pCARS feels most natural. Though every car is still being tweaked too much to give a proper initial verdict during development.
I think iRacing would be second I think if properly adjusted per car. Though I wish they would tweak the cars so that the FFB forces or more equal in strength/feel through the wheel, so that no per car adjustment is mandatory.

 

[fatkrakr]

I am not such an iRacing fan. Especially since you need to adjust FFB on a per car basis.
The last time I ran iRacing for a test run was a few weeks ago with the Lotus 79. I wasn't impressed at all.
Actually lately I am not feeling slightly satisfied with any game FFB wise other than pCARS, which makes me feel like a fanboy because of this single preference. I tried every beta and released game to date except Assetto Corsa, and from this pCARS feels most natural. Though every car is still being tweaked too much to give a proper initial verdict during development.
I think iRacing would be second I think if properly adjusted per car. Though I wish they would tweak the cars so that the FFB forces or more equal in strength/feel through the wheel, so that no per car adjustment is mandatory.

You do know that in iracing you can check the save settings for this car box and set FF one time per car. Every time after that it will load your saved FF settings. Also all your button mapping will be saved.

 

[Cote Dazur]

Pilmat put our attention on whether you use a hydro/loadcell/pot setup you can acheive similar feel under your foot and that the worshiped loadcells and hydraulics are not the only way to produce a quality realistic brake pedal.

- Hydraulic setup measures force using a linear sensor and has a realistic dampened feel. Worshiped on iRacing forums, costs around 26 fortunes.
Well, it's a good option but the cost is astronomical if you use other than refurbished/junkyard parts.

- Loadcell also measures force in a linear manner but setting it up to make the pedal feel realistic is a bit more hassle. Is kind of affordable.
IMO CSP V2 is the best design that's using a lc, though there's still things I'd do differently.

- Potmeters/hall sensors. If you want a realistic brake using these, you'll need some creativity and ingenuity. It's not impossible but is a bit more complicated than with a loadcell. Really cheap in comparison.
MrBasher's skateboard bushings mod to T500RS pedals is probably the best example of this to-date.

IMO Hydraulics' feel would probably be rated 9 (from 1 to 10) but the price is worth 3, so that's an overall of 6. If one would make a pedal using pots that would have the feel of 7-8 and the price of 10, it would be a pedal with 8.5-9 overall. That makes it a better pedal in my book.

Ofcourse for people who take the pricetag out of the equasion, the expensive set makes a better pedal.

Short version: The computer interface isn't the problem. Our focus is on the feel of the brake pedal.

Jet, I love your post, as to me it resume the situation very well. that is why I am quoting it.
My question is primarely to Pilmat and of course everyone else.
After following first this thread and then the other on the Build, I am coming to the conclusion that the first statement about the possibility of a pot brake system being as good as load cell or Hydraulic is not valid, with load cell beeing the best if cost is an issue and Hydraulic the best if the money does not enter the criterium of evaluation.
Is that it?

 

[LogiForce]

You do know that in iracing you can check the save settings for this car box and set FF one time per car. Every time after that it will load your saved FF settings. Also all your button mapping will be saved.

Yeah, I just keep forgetting to do it.
Still, I think it might be better to try to equalize it a bit more though. *shrugs* Maybe I am just too lazy with weird things.

Now let's get back on topic... *points upward to Cote Dazur's post*

 

[Jet Badger]

Continuing the bang for the buck topic, I thought I'll put a loadcell in my DIY CSP(P standing for Plywood ) pedals. I had already had plenty of loadcells so it was just the matter of making it work in the pedals.

I used the one on the left

The bracket pivots on the steel rod (the rod will be locked in place someday...)

A loadcell is definitely a convenient small package for measuring pressure but it's not neccesserily an exotic thing. The whole pedalset set me back less than $20 so far

 

[Zathra5_]

This looks like exactly the wrong way to design a brake system: http://www.totalspanishsimulator.com/wp/en/blog/proximo-mod-freno-g25g27/

They've got a damper and spring system and are measuring distance (not force) with a Hall sensor. Most mods for G27s that still use the pots(distance), do it by increasing the spring stiffness. Therefore, distance will be proportional to force so your body can use a combination of force and distance as cues to how hard you are braking. With the above system, you are removing force as a cue to how hard you are braking because the damper will resist how fast you are pressing the brake, not how far. Additionally, the damper could affect brake response by making it harder to apply the brakes quickly or release the brakes quickly.

 

[Jet Badger]

I don't really think so. I think it's a great idea aslong as the spring resistance is much heavier than the shock resistance. The white rubber part seems to be invovlved into action aswell. It seems to work like a Nixim kind of mod plus a damper, IMO it should work well.

 

[pilmat]

This looks like exactly the wrong way to design a brake system: http://www.totalspanishsimulator.com/wp/en/blog/proximo-mod-freno-g25g27/

They've got a damper and spring system and are measuring distance (not force) with a Hall sensor. Most mods for G27s that still use the pots(distance), do it by increasing the spring stiffness. Therefore, distance will be proportional to force so your body can use a combination of force and distance as cues to how hard you are braking. With the above system, you are removing force as a cue to how hard you are braking because the damper will resist how fast you are pressing the brake, not how far. Additionally, the damper could affect brake response by making it harder to apply the brakes quickly or release the brakes quickly.

I saw this elsewhere and my first thoughts were that it would be a miss due to the spring being linear. It is my strong belief that a sim brake needs a non-linear force curve, the shape of which should be close to exponential. But if they have built some kind of "spring" into the body too, then it could be very interesting. We would need to see the force versus displacement curve to know what's going on there.

The damping is interesting. After playing with the hydraulic brake, I can see some strong benefits to having some damping in a brake system. This is especially true on the release side as it can help a lot with trail braking (where you need the release to be very smooth). It can hinder on a position based force application as you mention as you will quickly build to a "false" position. But this can be handled through the damper valving if it is complex enough (remember typical shocks can virtually decouple the bump and rebound). By making the compression side quite soft and getting the return tuned to the spring, this might work very well (this is what the CSP2 is trying to do).

I don't think that just making a brake stiffer is the solution, and it seems they have incorporated some thinking into their solution beyond a heavy spring. We'll need someone here in the community to do some testing with one

Edit: Here is where I first saw the TSS Brake: https://www.gtplanet.net/forum/showthread.php?t=273109

 

[PiRacingChamp]

Anyone have a link to Century Springs? I am going to order my Rseat and perfect pedal later this week, and want to look into the springs to even out the feel across the three pedals.

 

[Zathra5_]

That is a pretty hefty damper that they are using. about 30% of the spring. Consider that when you first jam on the brake, the first ~120N of force is going to be from the damper with no braking force. Once the damper starts to give then you will get braking force as the spring compresses. If you press the brake slowly, you won't get a lot of resistance from the damper and so the resistance will be mostly form the spring. That just doesn't sound like a recipe for consistent braking. Might not be incredibly huge but it's definitely not going to be a benefit. If they put the damper and spring in series, they could have measured deflection of the spring. Then braking force would be proportional to the force you put through the pedal. Or they could have used a load cell. Either would have worked better.

Edit rather than double post: Apparently it isn't really a damper, more like a progressive spring. Sounds like a much better solution. From iRacing:

"It's not a damper exactly.

Only is to avoid the rebound of spring when released it (to make it real)

If you push the brake slowly or quickly, you'll have to do the same force.

The spring is 6.5kg/cm (in 3,5 cm of route, 22,75 kg)

The "damper", 1,8 cm - 1 kg, 2,4cm - 2kg., 2,9cm - 4kg, 3,2cm - 10kg, 3,5cm - 20kg "

 

[zed300]

Great thread and a great read. All input from a number of views and some insite to a question we all ask, once we have used a set of pedals for a while.
Muscle memory is a large part of good braking, along with mental comfort.(being happy with what you've got) Another is, a high frame rate. Obviously this only relevant to pc users. The higher the fps the more feed back the game can send the wheel and pedals, give a better "feel."IMO

Btw, I have G27 pedals on a Leo Bodnar with a DFPwheel. My brake has a 2cm piece of spear gun rubber inside the standard spring. This gives me about 1.5 cm travel, 2/3 of this is deadzone and then about 1cm of compression till the pedal dead stops. Which is way past the load I like to apply.

If the digital curve could accelerate, the closer to get to the end of the stroke, this would help me I think.

 

[PiRacingChamp]

Any links for Century Spring?

 

[ravey1981]

The higher the fps the more feed back the game can send the wheel and pedals, give a better "feel."IMO

Is this actually true or just an opinion? I'm only getting around 50fps with my underpowered laptop at the moment...

 

[alex2000261]

I can't agree I must say that upgrading to a load cell has changed something, it has definitely changed how the brake feels.

Think about it... a game reads inputs in one form, CORRECT, but the pedals reads inputs from your foot, so if your using a pressure sensitive load cell it will read the amount of pressure you apply and then send that data to the game. A potentiometer will read how far you push in the pedals and send that to the game, or am I just missing something?

 

[PiRacingChamp]

Rseat and PerfPed ordered. Now if I could just find the Century Springs, I'd be there.

 

[Zathra5_]

I can't agree I must say that upgrading to a load cell has changed something, it has definitely changed how the brake feels.

Think about it... a game reads inputs in one form, CORRECT, but the pedals reads inputs from your foot, so if your using a pressure sensitive load cell it will read the amount of pressure you apply and then send that data to the game. A potentiometer will read how far you push in the pedals and send that to the game, or am I just missing something?

The load cell doesn't change how the brake feels. It has almost no contribution to the mechanical properties of the brake. It is way too stiff compared to the rest of the brake's mechanics.

From a theoretical perspective, it doesn't matter whether you measure how far you push or how hard you push if your sensors are accurate enough and how hard you push is directly related to how far you push (which it essentially is for most systems). If your brake measures how far you push, it can calculate how hard. If it measures how hard, it can calculate how far.