Driving epiphanies


(Lee Swindell) #1

I’ve been reading the experiences Warren shares at intuitivespeed.com. Check this out if you haven’t already. He writes with passion, clarity and honesty about the experiences that shaped him as a driver starting decades ago.

Which has me thinking that we should, if were inclined, all do the same.

What were the ‘ah ha!’ Moments that moved your game on as a driver?

Mine was learning about what, I guess, turned out to be slip angles.

There’s a sweeper at the end of a long downhill straight at my local track when I was a kid. No one in my class could get through it without lifting, but rumour had it that one or two of the fastest guys in the best gear had managed it by scrubbing speed. And that became my mission that day - to conquer the scary sweeper.

I reasoned that the kart (even though I had crappy gear under me) could probably do it, and the limitiaton was almost certainly me. Specifically, my reflex to lift and brake before turning in. If I could replace ‘lift and brake’ with ‘lift OR brake’ I’d be halfway there. So I spent half an hour hitting that curve with the throttle pinned and a firm press of the brake. Next lap, that firm press became a light press, light press became a tap, tap became brush, brush became breathe - until finally it was done: I was routinely doing what I’d heard no one else in the club could, which was driving the sweeper completely balls out.

As my speed increased during this exercise my line had to change with it. And this was the epiphany - in order to do this I had to stop aiming at the apex and aim instead a metre INSIDE the apex - in other words, on a collision course with the barrier had there been one there.

Im convinced that many top level drivers have never discovered this - they’ve made millions aiming AT the apex. I might be wrong of course - but I’d spent years trying to understand what seperates the good driver from the great. And all I’ve been able to come up with is what the driver does turning in. How was Nigel Mansell able to lap a second faster than Riccardo Patrese in the same car at the same track in the same conditions? My conclusion: by driving a suicidal line at a suicidal speed on the way in, knowing the slip angle will carry him through.

Any of the coaches out there care to comment on this?

So … that’s me. Who else?


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(Mike Clark) #2

I’m having trouble remembering an epiphany. Probably because of other things I did before cars. We rode lot of dirt bike. I rode a lot of bicycle. I also read everything I could get my hands on. so some things I was forewarned about.

One of the biggest things for me was learning about exponential results.
Corner radius being exponential to speed.
Braking distance being exponential to speed.
Aero Drag/HP being exponential to speed.
The first two relate to driving and help understand why ‘the line’ curves the way it does.

Next 2 are how much power you have with your feet (in a car) & how much you tire can scrub speed.

Next 2
At some point you start to focus on time vs speed
Start to see what over-driving is doing


(Warren Chamberlain) #3

Lee, thank you very much for the kind comment, but maybe the decades ago bit wasn’t necessary. :grinning:

Your post made me laugh because it reminded me of my first year of racing; there was a similar turn at Ontario Motor Speedway (T9 that lead onto the back straight). About my 3rd weekend of competition I decided I was going to do it flat, so I worked up to it as you described, and then came the moment of truth. I pinned it, turned in, and everything was going swimmingly, right up until I got a big twitch… and then spun.

The chief instructor, Jacques Couture, kept us on a short leash, and really gave us hell if we made a mistake in practice. So I was dreading having to report to the pits for a ‘discussion’ about my transgression. When he knelt down next to my car (my parents actually got a couple pictures of it),…

I said “Before you say anything, I didn’t just throw it in there; I was trying to do the turn flat, and worked up to it step-by-step.” He just gave me a look, so I continued “Would you rather have me try that while I’m leading a pack of your cars?” He gave me his version of a smile and nodded me back towards the track.

I learned that day the importance of mentally extrapolating out as many of the possible consequences of a driving input change as you can (along with corresponding recovery plans). Once you’ve thought things through, then visualize the various scenarios so that you are less likely to become overwhelmed (aka experiencing an elevated sensation of speed) if reality does not go the way of your ‘primary’ plan.

What you’re describing (the influence of slip angle on line) is what I call driving a trajectory on a line, which if the 5th (final) core skill on the Spiral to Speed, It’s prerequisites are having the sensitivity to really feel the slip angles (core skills 2 & 3), and the ability to use that knowledge to control where, when, and how quickly the car rotates into, and out of, a turn (core skill 4).

I don’t think a driver could get to F1 unless they at least empirically know these things (or Dad is REALLY rich), but, while fast drivers know or feel this stuff, I think the elite drivers at some level intellectually ‘understand’ driving a trajectory and the related skills. Put another way, you don’t have to know music theory to enjoy music, and maybe even to write a great song. But knowing music theory makes you a more complete musician, and gives you greater confidence to break the rules, explore different genres, etc.


(TJ Koyen) #4

I was consistently about 3-tenths off when I first moved up to X30/Leopard, and no matter what we did to the kart, it felt like it always handled the same. It was getting frustrating and I was completely at a loss as to how I could’ve won so many national races just a few years ago and now I was firmly in the mid-pack most weekends. During a track walk with Jamie Sieracki once about 7 years ago, he explained the driving style on sticky rubber/high-power to me and it was like the light bulb went off in my head and we coined the term “driving under the rubber”.

Essentially I was always turning in about 5 feet too late, late-apexing every corner, and as a result, I almost always needed more front grip from the kart because I was asking the kart to do a lot of turning all at once, outside of the primary race line. Jamie told me I needed to hit the same apex, but turn in sooner and slower. So I did, keeping the kart loaded more progressively and digging into the rubber on the track through the whole corner. The kart’s understeer went away. It was an instant .3 that day. From that day on it’s been the basis for all my driver coaching.


(Dom Callan) #5

So you are keeping the same late apex point but doing a long slower earlier turn in to the late apex?


(TJ Koyen) #6

For some corners yes. Obviously every corner requires a different apex, but in general one of the main mistakes I see from drivers is they don’t turn in progressively enough, and they try and force the kart to do a lot of work all at once, overloading it and causing handling issues.

Also, of course, every chassis requires a little different driving style. Since I’ve been running OTK mostly for the past 6 years, the kart is very front positive and requires some real patience on turn-in.


(Lee Swindell) #7

Mike:

This was valuable for me. I’ve long understood the inverse relationships in driving - increasing input on one control requires decreasing another - but you’ve reminded me that the relationship is inversely exponential. A small increase in v requires a much bigger increase of r than my simplistic mental model had suggested.

This will be front of mind during the enduro I’m running on Sunday.

Thanks for contributing.


(Dom Callan) #8

No AHA! moments yet. Nick and me are doing some video training with TJ and some of the stuff he’s saying makes a lot of sense and has gears turning in my head. He talks a lot about keeping the chassis loaded and I think I’m starting to get an idea of what he’s talking about. Warren discusses the same thing, in a different way. If I’m going to get an AHA moment, I’m pretty sure it’s going to be around what im doing with my feet and when I do it relative to the entry, apex and exit of a turn. Either that or it’ll be something totally out of the blue.


(Lee Swindell) #9

Warren:

Don’t feel bad about having a few decades under your belt. Us old guys learned the craft when karts had square wheels made of stone. I think it does much for our credibility.

Your comment about elite drivers dovetails with mikes comment above about exponential relationships. Maybe the best guys just are better at ‘exponential’ driving than lesser guys who think more ‘linear’, as I’ve been doing (I think).

Cool story about your driving coach BTW. Nothing like having your ass kicked by authority to slap you into shape.

Thanks for writing.


(Lee Swindell) #10

TJ:

Awesome revealation. My big moment was the slip angle one. It sounds like your ‘driving under the rubber’ is turning in inside the rubber and ‘slipping’ into it using the distortion of the tire?

What should the turn in look like on a graph of lateral force versus time? In theory I’d have thought it should be a straight line as near to vertical as possible, capped out by a horizontal straight line. In reality the abrupt angles on the graph would be curves that reflect the time it takes for the ‘elastic’ in the system to tension.

I guess the shape the driver makes in that curve is what separates the men from the boys (which again goes the mikes post about exponential relationships).

Love this. Thanks for sharing.


(Warren Chamberlain) #11

This topic is really interesting because the technique TJ described for taking advantage of built up rubber to get his kart to rotate into turns is exactly the same technique I used to keep my formula ford from rotating too quickly into high-speed turns.

Lee, I don’t know if it’s applicable to karts, but, since you are enduro racing this weekend, I’ve described my experience and the technique in that context below.

In Turn 1 at Thunderhill Raceway Park in Northern CA, My formula ford was excellent most places around the track, but in the fast (110MPH+) left hand T1 it was quite unsettled from turn-in to the clipping point (CP), which is common for low down-force “neutral handling” cars in high-speed turns. Anyway, the instability caused me to delay picking up the throttle after turning in, which was costing me a lot of time. So I tried turning in a little earlier than usual (a few feet), but I turned in slower, so I ended getting to my original CP, but on a more favorable (shallower) trajectory.

The early/slow turn in reduced/retarded the initial rotation into the turn, which induced a very slight push that really stabilized the car. This allowed me to go full throttle well before reaching the CP. (On the ‘standard’ line I had to wait until I was at, or even slightly past, the CP to pick up the throttle, and even then I had to be ginger about it). The push I had induced would continue until approximately 1/2 to 3/4 of the way to the track out point, at which point the car’s need to “rotate” around it’s center of mass to complete the turn would exert itself with a little twitch, which was very predictable & controllable.


(Mike Clark) #12

Lee,
I am very much like Warren “Speedcraft” in that I think the better understanding one has the more complete they will be. So sometimes in thing I get accused of “Thinking Too Much” and that type of thing. I have found it can be overwhelming at times to attempt to understand everything @ once. It almost takes on a cycle of understanding vs being confused by it all. I also like to fall back onto very simple premises when it all get confusing.
I compare things I have done and try to draw experience I can transfer. One thing I noticed in long range shooting is a lot of guy focus on range of a target. Fair enough we need to know drop and windage. Ultimately the thing that matters is time of flight - ToF. Range is only really needed to get ToF. Some guys don’t get why on different days the POI varies at the same range. Well atmospheric conditions changed so did ToF. Point being sometimes we make correlations that aren’t always direct. My daughter asked me one day if I rather shooting or racing. Very perceptive question for anyone that knows me. There are many similarities and I regard both as disciplines. Both have internal forces we can’t see and speeds making things hard to observe. Both reward restraint and aggression, and the better practitioner knows when to use which one. Both are threatened by next door neighbors . . . After talking with her and thinking about it more I found the restraint to be the hardest thing. In shooting a rifle I can only detract from it. I cannot make it do anything better once I am behind a given package. IE the less input the better. The epiphany there was to get out of the mindset that I was going to shoot that rifle better than another guy and realize the best I could do was hinder the rifle less. Then one day it hit me how bullet trajectories reminded me of “The Line” through a corner. Here is a hint - It make a difference if the graph uses distance or time on one axis. I should probably view driving a kart as the same.
When I am going well, I call it ‘Saving the G’. Think of keeping the friction circle rounded out. A mini epiphany is realizing friction circles are not necessarily round. So keeping the friction egg or friction blob filled out. How do you get from one direction to the other without spilling the energy into some place that doesn’t help. At Road Atlanta there is one section you could just add steering and creating more understeer, then unwind the wheel and feel it with little change in line. You could really feel it bog the car. In another corner you could really see how the throttle would change the yaw of the car and have it remain on line. Besides slip angle there is percent slip. While not generally talked about in road racing it does have some influence. With most karts only having rear brakes I would think the effect would be less than in a car. That could be counter-intuitive though.
With almost any equation I think looking at it backwards help understand it.


(Warren Chamberlain) #13

Mike, the way you think and your choice of words is really interesting to me!

This is why I think of learning racing as a progression up a learning spiral instead of a simple linear learning curve. The learning process folds back onto itself over and over. Like when you experience something new, and then extrapolate out what that experience means, and then realize that the new meaning you’ve discovered suddenly calls into doubt what you thought you knew about something else, so more evaluation is needed in that area, and then you discover that you might be able to push area farther than you thought… which impacts something else you thought you knew, and on it goes until you’re dead, or you think you know it all.:grin:

I actually use three interrelated and interdependent mental models to translate what I sense when driving into the information that I need to take my vehicle to the limit:

The Energy Cycle tm: Which represents both the time needed to build tire loads, traction, & forces acting on the car/kart, and, for each turn or ‘event,’ the time it takes all of the energy to cycle from driver input to energy/force equilibrium, and back to a neutral state where the energy is at rest (or relatively at rest) in the chassis.

The 3D Traction Circle tm: Which is a concept I created to understand/show the dynamic relationships between tire loads, traction potential, and slip angles. It’s essentially a variable size vessel that grows from nothing (no load) to maximum performance size defined by the width and height of optimum load/traction/slip angle/, to maximum diameter, defined by slip angles beyond optimum all the way to the tire scrubbing across the track sideways.

Speed as a Liquid tm; The perception of the movement of speed (kinetic energy) as a liquid: Which both ties the other two concepts together, and provides a visual metaphor for how I feel (or experience) driving. In my mind, I don’t ‘drive’, I:

  • Have in my mind the fastest trajectory on a line around the track for my current car/situation.

  • Have a tire loading plan for each turn that will allow me to drive the trajectory/line I want, while producing the most efficient use of my tires by controlling where, when and how quickly my car/kart rotates around its center of mass in each turn.

  • Execute the tire loading plan by pouring energy at the appropriate rate (in accordance with the 3D traction Circle and Energy Cycle) into my tires without spilling or wasting any of my energy/speed.

I realize this might sound horribly complex or confusing written out like that, but it’s really so easy; driving just becomes a game of energy management, and to make it easier, I only ‘drive’ one tire at any given time, which reduces mental noise and cognitive load, and allows me to have a very high level of sensitivity to the most important tire/Energy Cycle at any given point around the track.


(Timothy Strawkas) #14

I think EVERY driver has had that moment when they felt the very first “GOOD” 4 wheel drift as there number one moment. We all have the loose seems fast .it was free through the first part of corner, but till you “Really feel” that almost 4wheel drift, you’re left scratching your head what makes A kart go fast…


(Lee Swindell) #15

You guys are good

I’m going to need to reread these posts several times in order to do justice to what youve written here - but having scanned once and reread once, I’ll say this:

Mike, your replacing the reflex to ‘add value’ to your driving / shooting, with not ‘subtracting value’ from the exercise, dovetails with another epiphany from years ago - that the ideal state of motion for a race car is moving at its maximum speed in a straight line. Racing introduces turning and braking to make the exercise more interesting for us - but if a driver frames driving as the act of perturbing the race cars ideal state of motion to least possible extent, the driver is driving to not ‘subtract value’ rather than the reflexive-but-impractical ‘adding value’. So I agree - reverse engineering a solution from the theoretical ideal is a profound paradigm shift. I think it’s brilliant.

Warren: I was amazed to have your ‘driving as a liquid’ jump into my head as I was lapping yesterday! It’s a beautiful metaphor for this, the most analog of sports. I’ll be taking it into the enduro with me on Sunday.

It will take some time to properly understand the 3d friction circle (I find the interplay of the 3 axes challenging). Where can I read more about this?

I’ll come back with more when I’ve had time to digest more of what you guys have come up with. But this is already THE most interesting Karting thread I’ve ever read. Kudos, both.


(Lee Swindell) #16

Timothy: yep, none of us will forget the first time they felt their kart hooked up squarely on it’s 4 wheels in a fast turn, when the balance was perfect and the whole system momentarily maxed out. It’s an exquisite feeling, matched only by the 2 or 3 times I’ve ever managed to smack a gold ball perfectly off a tee.

It gives us reason to continue living.


(Lee Swindell) #17

Incidentally, I’m going to have a lot of time to think about stuff and observe stuff while I’m out there on the weekend.

What two simple things do you think I should focus my attention on in order to end this race a better driver than when I statrtrd it?

Thanks crew. strong text


(Warren Chamberlain) #18

Lee, I am (and have been for the last 6 months) working on the content for my web site’s Spiral to Speed CORE skill #2 - Optimizing Sensitivity entry. It has been a monumental, and exceedingly difficult task, and realistically still several months out because it has morphed into basically my manifesto of sensitivity.

However, I’ve thrown together a 10 page PDF file that, in very basic terms, shows/describes Speed as a Liquid, the Energy Cycle, and the 3D Traction cycle, along with their basic interactions. I don’t know if it will be clear enough to be of any use to you, but here is the link:

https://drive.google.com/file/d/1GqHaTgJ56MQArjHjbgSvckB1v224dWEX/view

I also created a GIF animation of the energy cycle/3D traction circle interaction process. I recommend looking over the PDF before viewing the animation. Also, I’m just learning the 3D software, so the timing of the GIF is flawed… if correct, the orange energy cycle and 3DTC would grow and shrink at the same rate. Anyway, here’s the GIF link

https://drive.google.com/file/d/1T69iiawj94YWRLRLedUVMRYZxtREEHK_/view?usp=sharing


(Warren Chamberlain) #19

Lee, I promise these are simple things; they just take some explaining.:wink:

Drive to a tire loading plan.
Try and approach each turn with the objectives (line, trajectory, and speed) in the background, and instead focus more on:

  1. Where, when and how you need to load the outside front tire to get the kart turned in and rotating at the location and rotation rate you need to be on trajectory.

  2. Where, when, and how you need to transfer the load to the outside rear tire to check the rotation so the kart is positioned on the desired trajectory to complete the turn with the power on.

In the Energy Cycle food chain, ‘load’ is above ‘traction’ and traction is above ‘forces’, so the more you drive based on being sensitive to, and controlling, loads, the more proactive your driving will be, which is a very good thing indeed.

Be lazy
By that I mean, trust the mental model of the track in your memory; don’t waste effort re-evaluating things you already know, or re-observing things that happen every lap. Only ‘think’ about things if there is a compelling reason to do so; otherwise just observer how well reality is matching what you already know/expect.

For example, many drivers use a myriad of reference points for every turn. If that works for them, cool, but to me that sounds like a paint-by-numbers way of getting around the track. I prefer to know the extent of my ‘canvas’, and then to get around the track by ‘painting’ what I feel.

What the hell is he talking about you may be asking yourself. Well, as it relates to the tire loading plan mentioned above, I would recommend using only a braking reference (if you feel you really need one) and a turn-in reference. Here is the reasoning:

  1. Decelerating for the turn begins the loading of the front tire
    (if you need a reference to be consistent with this then use one).

  2. The turning point is where you pouring the turning loads into the front tire.

  3. If you have done the first two correctly, there is nothing more to do other than be patient, let the energy cycle run it’s course and wait for the results of your loading to manifest. So, you can relax, and put your attention/awareness into just FEELING what’s happening.

  4. When your turn-entry tire loading plan eventually results in the kart rotating around it’s center of mass, then you initiate your exit tire loading plan (apply throttle & steering to transfer load), which should check the rotation so that the kart is oriented on the line/trajectory needed to complete the turn. At that point, you’re done again; just along for the lazy ride feeling what’s happening and waiting for the kart to complete the turn.

So, with a tire loading plan, instead of a plethora of reference points, you are trusting your knowledge of where you should be on the track, the speed you should be going, the trajectory you should be traveling, and the loads your tires should be carrying.

In my mind, all the extra reference points (for brakes off, or even-throttle, or throttle-on, or apex, or track out, or whatever) are just extra mental (intellectual) effort. But more importantly, they interrupt the ‘flow’ of sensitivity (the feel for what’s happening) you get when you’re not busy doing “driver stuff” at specific points all around the track.

Good luck this weekend!


(Lee Swindell) #20

Warren:

This is wonderful stuff - thanks for sharing. As with all your stuff I need to read and reread several times before commenting because it’s pretty deep. I love this stuff.

Makes me wonder whether you’ve already seen this - if not you should check it out. From New Scientist in 1993, the mathematics of the racing line. Ill send you the whole thing if you find it interesting.

I’ll be putting your mental models to work on Sunday. I’ll let you know how readily I was able to apply them.

Gracias.

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