Force Feedback & Physics

[pitkin]

Didn't really know where to put this, hopefully here is as good a place as any other.

I've been watching the Legends series on The Race channel on youtube recently and one thing interested me.
Some of the drivers have had interviews after the races. They've all been full of praise for the racing and enjoyment they've had, but any that I've seen commenting on the feeling of the sim (rF2 Brabham BT44B) have all said it feels nothing like driving a real car. This is largely because there's so much information from the car missing that just wouldn't be felt through the steering wheel.

I remember a story about Jackie Stewart having a go on the old king of sims, GPL. After his quick go, his comments were "if the cars actually drove like that, a lot more of us would be dead" People used to say "it's realistic because it's hard."

So my question is, why get so hung up on all this if its not giving us the whole picture?

Sure I'll agree that rF2 feels better than pCars 2 for example, but if those feels are such a tiny part of the picture, why worry? Seeing people slagging a sim because it's physics are simple seems quite trivial to me, because whatever they do, we can't feel cornering force on our bodies, we can't feel the rear of the car, traction loss, body roll, etc. Your only clue that subtle tap on the brakes has worked is visual, in the real world a lift on the accelerator is felt straight away because your body weight changes due to the forces. You can feel where the power is in the rev range, the biting point of the clutch, the brakes fighting against the momentum of the car. So much information is missing, what we end up getting is something falsified or exaggerated to try and relay some of that missing information.

My only real world comparisons would be owning Honda Pro Karts back in the 90's and a 125cc 2 stroke. I've not found anything sim wise that compares because it's seat of the pants stuff. Your own body weight transference makes a lot of difference to how well you corner, something that can't be translated into a sim.

The only other comparison is my kit car, a Dutton Phaeton (very poor mans caterham) with a 2 litre engine, about 140-150 bhp. It's cheap and cheerful, but it's light and fast and it grips the road like no other car I've driven. Because of this, I always jump into a similarly powered Caterham, if one is available in sim. Again, the information you're getting through a FFB wheel (okay, I only use a G29, so it's not gong to be as good as a DD wheel) is actually quite minimal.

I first felt good FFB in GPL, and I was amazed. I could feel understeer, the car going light, front brakes locking, bumps etc. It's all I look for really in a sim now as far as FFB goes, and most of them communicate that well enough.

As far as physics goes, I make setup changes, I can see a difference in lap times, but do I FEEL those changes? We talk of complex physics in sims, but I wonder how much is just a placebo? We're not fooling real drivers (unless they work for, or are sponsored by they sim maker.) So why not just have fun? It doesn't matter if it's rF2 or F12018, most of us will never have a real life experience to compare it to anyway.

Sorry that a bit longer than I intended, but I'd be interested to know if people think it's really that important in a home sim, when it's only giving such a small amount information in relation to whats actually going on in a real car.

 

[BrightCandle]

Ultimately the more accurate the physics of the cars are the better, if they handle more like real cars then that is what I want. The sim simplifications have so far often resulted in cliffs of grip and very unforgiving cars to drive and that clearly isn't the reality in real-world racing. I think most of us agree that the closer the simulation gets and the better data going into it is then the better. Niels Heusinkveld has been on a bit of quest recently to show us why it is currently difficult to near impossible to get it right from manufacturing data and presumably also from car telemetry. At some point, we have to go about getting more accurate data to drive the models for individual parts, we need better data collected in more sophisticated ways for the individual parts. Right now they are building simulated models of tires and using those at inputs but as we know that is also proving to be problematic in iRacing and its very hard to work out what is wrong and what to change from how it feels wrong.

Force feedback is a bit of a different challenge. Most sim racers are going to have a wheel and pedals and then mostly consumer-grade stuff, low-level Logitech and Thrustmaster kit. Since the lateral and longitudinal force on the body is important for driving the vehicle we have to find appropriate ways to allow it to come through the force feedback. I am of the opinion that the next stage in FFB is to by default use steering column physics inputs and then optionally allow people to add seat of their pants and enhancements for tire scrub, aero pull, ABS and other otherwise felt forces through pedals and the body into the wheel. These need to be more than just canned effects but rather dynamic FFB effects with lots of feel and variance to lean on. Some people choose to have them to varying degrees and that ought to be supported.

But one of the reasons you might not want to add that to the wheel is they can get in the way of other forces, so there is a priority to what appears in the wheel. Some of those forces on rigs with bass shakers and motion rigs are better sent out that way rather than through the FFB. Since the wheels have such different amounts of force, immediacy, fidelity and snappiness we also need to be able to adjust the forces to each other including within the steering column, hard to detect understeer is definitely a problem on weaker wheels as is finer detail on belt wheels. The project cars basic slider or custom is the wrong approach, the column only forces of ACC and iRacing are also the wrong approach. AC and RFactor are closer to what is better for users but I think we need an evolution of the idea to get good calibration of the settings based on the wheel or class of wheel selected.

A very real issue new sim racers often have is how to set the wheel up and what they are meant to feel. There are lots of different wheels out there and they are either faced with their control panel of relative simplicity or a lot of complexity (usually not easy to understand to begin with) and very simple or overly complex setup in a sim that they have to do as well. They find themselves trawling through forums taking random settings from people to try to improve FFB. AMS2 right now a lot of people are using a custom FFB found on the beta forums because it's better than the new default. This is clearly a big problem and it took me a year to settle on my AC settings and TM control panel settings, the defaults are just bad. This needs to change, we need to have people who know what these settings should be to produce the right defaults so that sims work well out of the box as they ought to feel. I think if we can't do that then we need better ways to export and import the settings so they can at least be shared, but I would rather a pro driver go about dialling it in to get the best out of a particular wheel for that sim. The situation clearly needs to change with force feedback, both in what forces various games support as well as how they are setup. Force feedback isn't really personal in the real world it just is and I am not suggesting we remove the ability to tweak but it ought to come as close as possible. those extra forces added in for consumer wheels need to be there by default and clear instructions for those not wanting those or those with motion and bass shakers to remove them. I don't think a lot of the new sims are getting this right at all.

 

[pitkin]

Hi BrightCandle, thanks for the detailed response.
I've previously watched Niels' video on tire data, it is indeed a complex issue.

I guess what I'm getting at, is no matter how good the physics claim to be, I've never felt that it's like driving a real car. Without the forces felt on my body, the biggest and best part of driving on the edge, for me at least, is missing. This is something that will probably never be solved outside of multi million dollar rigs used by manufacturers. Because of this, we can't 'feel' the complex physics at work, it will always be an incomplete representation. If it's incomplete, is it important which bits are missing?