Driving Technique
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"Corner entry is arguably the single most challenging aspect of competitive driving."


Vivek Goel has an excellent blog called Beyond Seat Time.  "I am an ardent student of racing, the underlying physics, psychology, and motivation," says Vivek.  "I have 13 years of competitive driving (autocross, pro solo, HPDE, time attacks, etc) experience, of which 9 years have been competing at national level with growing successes. I wasn't very good when I started, but I had great drivers, friends, and help around me, and leaned on a lot of books and videos."  Here is his contribution on braking.  

The Visuals of Braking

by Vivek Goel

visuals of braking 360pxCorner entry is arguably the single most challenging aspect of competitive driving. Braking, which is a major component of corner entry, is really challenging in its own regard. Our terminal speed on the preceding straight is determined by when we begin braking, our turn in is affected by how we release the brakes, our entry speed and the line we take around the corner is dictated by all of that and more. So today, let’s discuss how to optimize usage of visual cues when braking for a corner.

We make driving decisions based on various sensory inputs, or cues. Some of these cues are auditory (tire noise, engine rpm’s), some are kinesthetic (g-forces felt through the seat, steering feel). To a lesser extent we even use our olfactory senses, though usually only when something bad is happening (am I on fire?). But the most important cues are visual. All of the others certainly help paint a fuller picture, but visual cues are the one that we just cannot do without. Beyond just needing to see where we are going so that we don’t run off the track, we are all aware of the concept of looking ahead. We look ahead in order to give our brains the visual information it needs to draw the optimal arc from where we are to where we want to go.

Take a moment to honestly assess your own skills with looking ahead. Try to visualize yourself going through the various phases of a cornerturn in 2 (braking, entry, middle, exit). Pause your mental video during each of those phases and try to critically assess where you tend to look during that phase of a corner. Turns out that most of us have an easier time looking ahead during corner exit, but drivers of all skill levels report that looking ahead during braking and corner entry is really hard to do consistently. We need to take a closer look to understand why that is.

Let’s understand the problem so we can solve it

Lucky for us, the problem is literally right in front of our noses. Here’s what typically happens: As we come barreling down the preceding straight, our eyes scan ahead to pick up our braking point, turn in point, and maybe even the apex if we are really disciplined about looking ahead. So far so good! However, as we get closer to our braking point, our vision narrows and shortens to focus completely on the braking point. Of course, this focus on the braking point is well intentioned; less experienced drivers use it to ensure they don’t go sailing off the track, and more experienced drivers use it to really nail their marks. But either way, the unfortunate consequence is that our broader perspective gets broken, and we start looking from point-to-point.

With longer braking zones, our focus is first drawn to the braking point. Once we nail the brakes, our attention shifts to the turn in point. After we begin our turn in, our attention shifts to the apex… and so on. It becomes difficult to resume looking ahead because we start perceiving each of these points as individual events. We get focused on braking at the right point, turning in at the right point, and reaching the apex as if they are discrete events, instead of carrying maximum speed on the arc that connects those points. With shorter braking zones, the only difference is that we skip focusing on the braking point, and instead start by focusing on the turn in point, and continue the point-to-point vision thereafter. The same thing occurs with autocross, where it is easy for our vision to get completely locked on the entry cone in an effort to brake as late as possible and get as close to the cone as we can.

In all these cases, the issue is the same: Even if we are on the absolute limit going from one point to the next, we are doing so on a suboptimal line, likely at a suboptimal speed. This is not just an issue that newer drivers face; even very experienced drivers struggle with this. Now that we know why it is harder for us to look ahead when braking for a corner, let’s talk about how we can fix this!

1. The irrelevance of the turn-in point

turn in 400pxGetting on the brakes at the right time is obviously critical for a good lap time and safety. Let’s frame the braking point as the point where we hit the brake in order to put us on the most efficient path through the apex. There are two things to notice about this reframing: (1) We are not looking to get to the apex, our focus is on the path through the apex. This is an important distinction, as it pertains to the angle at which we pass by the apex, which is informed by our vision as we look through the corner. (2) There is no mention of a turn-in point! This is not an oversight; it is a realization that instead of being a marker we look for, the turn-in point is a consequence of the speed we are carrying and the path we wish to carve through the apex. Assuming you are at the limit of traction, if you turned in too soon, it means that you can brake later (or less) and carry more speed in; if you turned in too late and missed the apex, it means that you need to brake sooner (or harder). A turn-in point is thus a meaningless visual cue; our turn-in is informed by the arc we want to carve and the speed with which we want to do it.

For corners with longer braking zones, this implies that we can shorten our vision and pay attention to our braking point if we absolutely need to, but the moment we get on the brakes, we can skip focusing on the turn-in point, and use that time to lift our eyes up and resume looking ahead through the corner. Doing so will give our brain the information needed to draw an arc through the corner, which will automatically let us know when to turn in. This way, we maximize our chances of being on the limit of traction on the optimal line, rather than focusing on a sequence of points and relying on memory to keep us on an arc through the corner.

For corners with shorter braking zones (or every autocross corner), we don’t typically focus on a braking point anyway, and as we just established we can skip focusing on a turn-in point or entry cone as well. Thus, without any short range marker left to focus on, we are free to keep our eyes up through the apex and to the exit, which will give us the information we need to turn in at the right moment, with the right speed, to stay on the arc of our choosing. Remember, it can only be an arc of our choosing if we gave our brain the information needed to actually choose the arc.

The simple but important point is that by eliminating the need to look for a turn-in point, we make it easier for ourselves to keep our eyes up to look ahead through the corner.

2. The power of peripheral vision

While we’ve established that the turn-in point is irrelevant, the braking point and apex certainly remain vital. However, looking at these points doesturn in 3 400px not mean staring at them. Our eyes have a wide field of view, and we can utilize our peripheral vision to see things without having to focus on them. Instead of staring intently at the braking point, we can keep our focus up looking through the corner, while letting our peripheral vision pick up the braking point. Similarly, once we turn into the corner, instead of staring at the apex until we pass it, we can keep our eyes up through the exit and towards the next element while our peripheral vision picks up the apex/cone. In other words…

Look at the apex as early as possible. Look through the corner as early as possible. Let peripheral vision do the work of identifying what is right next to us.

Admittedly, while this sounds easy to do, training ourselves to rely on our peripheral vision is fairly challenging, and is the reason why driving/racing schools spend so much time emphasizing vision. This is something we can practice when we are driving, and taking an appropriate school is always a good idea, but the good news is that we can work on improving our peripheral vision (and our response to it) even when sitting on the couch.

When approaching your braking point, try to keep your eyes focused on the apex (green circle) and let your peripheral vision pick out the braking point (red circle)

As you approach the apex, try to keep your eyes looking through the next element (green circle) and let your peripheral vision pick out the current apex (red circle)

TAKE ACTION: Work on reacting to your peripheral vision. Practice while driving around every day, or at the track, and work on it at home too. There are a number of exercises and games to be found on Google for training and improving peripheral vision.

3. Let’s take it one step further…

One of the best pieces of advice I received was from a European Le Mans championship winning driver, who suggested not thinking about braking from the perspective of when I want to get ON the brakes; rather, to think about it from the perspective of when I want to get OFF them. We already do this every single day when approaching a stop light; we know where we want to finish our braking, and automatically figure out when to get on the brakes and how much pressure to use. With a little bit of effort, it is relatively easy to build the habit of doing this at the track. Just as we typically learn our braking points by choosing a conservative/early marker, and working our way forward/later depending on how much brake pressure we had to use, we can do the exact same thing, except instead of looking at a brake marker, we do this exercise while focusing on where we want to finish our braking. This works regardless of whether you trail brake deeply or get all your braking done in a straight line because you have the freedom to choose wherever you want your braking to end. The added benefit is that because you are focused on the end of braking, your brake release automatically improves significantly! Just remember not to stare at the brake release point; keep your eyes moving through the corner, and use your peripheral vision.

Once you get comfortable with this, you will have nothing interrupting your ability to look ahead on any part of the track. Between the improved track vision and better brake release, your corner entries will improve dramatically.

TAKE ACTION: Work on this consciously when driving around. When approaching a stop light, try to pick the appropriate pedal pressure such that you need to make minimal adjustments as you slow down. This will help improve your depth perception and pedal pressure control. Work on this at the track by consciously focusing on where you want to end your braking, and gradually develop the sensitivity necessary to do this with maximum efficiency.

A closing thought

We tend to only think of brakes as a device to slow the car down, but they are also a device to move weight, and thus, to change the level of grip. If braking transfers weight forward, then that gives us more front grip, which means that we can enter a corner with more speed, which means we can brake even less or later. 

Read more at http://www.beyondseattime.com/

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