winders

My point, Peter, is that for that tool to be useful, drivers need to be able to get feedback from it at precisely the time they are least likely to be able to pay visual attention to it. A predictive lap timer, or even checking RPMs after corner exit, allow you to look at the feedback device after the high stress moment(s) has passed. You can't get the same kind of feedback from a lap timer or tach though.

This is why I suggested audible feedback since it needs to be realtime and not require a disruption of other senses needed for driving at the limit.

But hey, dismiss what I am saying if you want....

Veloce Raptor

To me, this tool isn't particularly useful for folks at the pointy end, for exactly the reasons Winders states.

RobertR1

https://www.linkedin.com/pulse/drivi...nd-willem-toet

"So Michael had his little remote speed display, he used it to help with his driving technique, but then he commented that he felt that it wasn’t quite as easy as he’d thought to read. He said: “In the middle of a corner, when I’m making the apex, it’s a bit hard to focus on the speed. Things are changing so quickly so you can’t really watch the speedo and be sure that you’ve seen the lowest speed. Then, if you want to watch your top speed at the end of the straight, it’s not so easy to watch there either because you’ve really got to be watching for your brake marker.” So what he said he would really like now was 3 speed displays. I suspect at this point we looked a bit puzzled so he explained what he wanted: “I’d like to keep the real-time speedo in the middle, where it is. Then on the left I would like a speed display that shows the minimum speed in a corner. It should hold that speed until I go for the brakes again. Then when I go for the brakes that can be reset to give me the new minimum speed. Then on the right I’d like another speed display to remember the maximum speed I reached until I’ve been flat on the throttle for a second or two so I can read the maximum speed from the previous straight”. Richard went back to work out how that could be done and gave Michael that arrangement. You can imagine that the displays themselves and the way they were configured went though some iterations. "

I always thought Schumacher had a very simple and brilliant plan. I'd love to see car manufacturers or data guys incorporate something like this into the newer digital dashboards.

ProCoach

I hear you, Scott. This tool is not for you. And I know few drivers relying on anything but their hands, their eyes (focused outside the car) and their butt, in "high stress" situations. But they can look at the result of their efforts after those times to determine their efficacy.

For decades, the Jim Russell School, the Skip Barber Racing School, Bondurant, Roos, you name it, used RPM reading at track out as the "golden carrot" of instantaneous validation of doing better (or not). Why, because it's simple and it works.

The thousands of intermediate to advanced DE driver (including instructors) drop time from inconsistent braking, and between the end of braking and the assumption of max cornering load. THIS is where this tool can help those drivers determine where and how (and most importantly IF) they are fixing this deficit. That's all.

And it's not designed for "gods of speed" (thanks, Bruce MacInnes). It's designed to provide real-time feedback a lot of drivers come to rely on from the right seat (or at least, the sensible people who I've ridden with) who are looking for validation and calibration of "how close am I?" As we both know, most beginning and intermediate drivers have moments of "flowing brilliance" but could (and do) use the information given from the right seat to know where to push, in an incremental way, more. This is just another tool that supplies better, vetted info and can shorten the learning curve for those lower on it.

GREAT post! Willem Toet is an awesome engineer.

But this technology DID and DOES exist, in some systems, and has since the mid-1990's (about the time Toet integrated this feature into the Marelli Digital Display Unit (DDU) in his F1 car.

It's called "latching" speed readings. Min cornering, max straight, compound corner min are all available, constantly refreshed for the driver to review (when they have time, Scott).

Pi Research pioneered this feature, but now most pro level, high end systems do this (MoTeC, Bosch, RD2, MM, Cosworth), even the Traqmate TraqDash does this.

Great tool and gives keen insight into driver (and car) performance. AiM has already been told it's an important feature to integrate in the future. As Matt would say, it's just math...

RobertR1

That's good to hear that current systems already have those features.

Outside of the commonly used predictive lap time, can't think of what else that would beneficial without being distracting.

zzyzx

"Give me a while to compose a more detailed response, but you butt is not lying to you. Entry point accuracy ALWAYS takes second fiddle to apex accuracy. Apex accuracy ALWAYS takes priority, period. Think about how long you're turning through a corner, think about how long it takes before you can go back to power (WOT power). "


Thanks for your response. The traditional way that line theory (or cornering theory or whatever you want to call it) has been taught is that the entry is just as important as every other part of the corner. However, it just doesn't feel that way.


I think the idea is that being 3 feet in from the edge of the track is just as bad as missing the apex by 3 feet because either way you are changing the radius of the corner by the same amount. I'm not sure if this is true though, and like you said, it just doesn't feel like it.


Maybe the apex has a bigger effect on the radius? I can't picture it in my head.


I often see pro drivers not always using all the track on the entry (and not just for bumps or other pavement issues), but seeing them missing an apex is clearly a mistake.

Manifold

If you miss the apex by X feet, that error will propagate and magnify through the rest of the corner, so you have to slow a lot in order to stay on track. That slows both the corner past the apex and the speed down the subsequent straight, and also has obvious safety implications.

OTOH, if your corner entry isn't quite optimal, you can usually adjust the entry to still get a decent apex and corner exit.

Because of the arrow of time, the two scenarios aren't symmetric.

zzyzx

I've been reading Adam Brouillard's "Perfect Control." He talks about the Euler spiral, which a physics concept that he applies to corner entry. I haven't totally understood what he means. Have any of you coaches read this book? Can you explain the concept?

Manifold

All three books in that series are outstanding, best driving books I know of. Fairly heavy reading though.

To optimize a corner, you'll typically be adding steering input all the way to the apex, which means a decreasing radius curve (spiral). If you're at or near the limit, you'll also be decelerating to the apex (depending on the corner, the deceleration might be initiated after turning in) if the corner requires deceleration, and may need corrections to manage the car.

ProCoach

That's correct. Perfect example is Rene Rast's Bathurst lap in the R8 LMS. This is what great Ams and good Pros have been doing for years.

One way to validate this is gSum colored map overlaid on GPS track of the car from end of braking to apex, cross checked with radius and speed at multiple points going in.

Once you DO it, it's an "a-HAH" moment and you can do it again and again.

Matt Romanowski

Great books! I think I first read the second one, then first, then third.

To expand a little, he is talking about a few things. The first is that the speed reduction in any corner is not just the brakes, but the additional friction from turning the car. Second, he talks about getting the proper angle of the car at the apex, not just being at that point (the heading / vector of the car at the apex is critical). Finally, he says to do this you have to do more than just turn the car at the turn in point. I think it takes a 2-3 reads to really understand what he is explaining.

In the end, I don't think he's saying anything really different than other driving books, but he does it in a bit of a different way. Once you understand his explanation, it's very good.

Gofishracing

This ? https://www.youtube.com/watch?v=OCs_i6FYV9o

ProCoach

Yes.

Would be better if it showed steered angle, corner radius or a view of the steering in-cockpit, but the "blending" of the tighter radius (steering added) as a spiral design, with brake pressure on but ebbing, down to the apex, then immediate progressive (not slow, either) power on is the execution of this idea.

Jorge Segers posted a good video with tracked radius on this circuit a few years ago. THAT is incredible. I'll see if I can find it. If not, I'm sure Matt will.

zzyzx

Regarding the video, it's really impressive how deep he brakes into the corners, and how, with left foot braking, he is at times simultaneously on the gas as well near the apex. I can only imagine that for someone who didn't grow up left-foot braking on karts, it has to be incredibly difficult to master this technique of simultaneously braking and also using the throttle.

zzyzx

I think I understand the concept of the Euler spiral a little better.
Basically, it's like a transition curve that you sometimes see with freeway off-ramps.
It makes sense that at the very moment that you turn into a corner, you wouldn't dial in a lot of steering since you are waiting for the load to transfer.
So in the sense the entry line (from the entry to apex) is a decreasing radius line, correct?