Saturday 12 February 2011

Steering methods

How to steer your vehicle? does steering have an effect on the ability of a motor-vehicle driver to control his car? While not being the most important chapter in car control, steering techniques do make a difference, and can save time, effort and even help maintain the direction of travel where it would otherwise be impossible. Most big institutions in the advanced driving and racing world tend to teach one steering style or the other, out of nearly two-dozens of styles that exist! A steering technique can help turn more steering faster and with more feel and finesse, while investing minimal effort into the movement. 

There is a vast variaty of styles, which we will not explain here. I wish to move directly into the explaining the technique I advocate and it's advantages. One could view it as one technique, a combination of some "tools" or a technique with several variations, and I explain:

First, the basic grip of the wheel. Having set the seating position, we now grip the wheel at 9 and 3, which are both edges of the wheel. The palms should be cupping the outside of the rim, and whenever driving on normal tarmac roads, the thumbs should be hooked lightly into the sockets created by the crossbrace of the wheel. The grip of the wheel is ought to be soft, just strong enough to keep the wheel controlled. There are various ways that help deal with the phenomenon of "squeezing" unto the wheel:

- A proper seating position
- When cornering or braking hard, applying support with your left foot, so that you do not need to lean over the wheel.
- Take deep breathes before a high G-force corner. Wiggle the fingers on straights, one hand at a time.
- Feel the wheel mainly through your fingertips, the most sensitive part of your body, save the lips. It's not that you cannot use the palms and thumbs too, it's just that the main sensory input should be the fingertips.

With many cars, adjusting the seating position right for 9 and 3 allows for a vigilant and comfortable posture. If we look as the steering grip apart and assume a driver might get his hands right without setting the seating position appropriately, or if we assume the car does not allow that person to reach an adjustment close enough to optimal, this position might become somewhat inconvenient over long periods of time, but it's nothing too bad and the hands can be momentarily moved to a higher position (the tradition 10 and 2). Move the hands one by-one and not both toghether.

This position is our "homebase" for car control and it should be maintained for as long as possible, and this is part of what a good steering habits seeks to achieve. This position allows us to, at will or when surprised, to turn the wheel up to 270 degrees with both hands, to each direction. While the crossing of the forearms appear odd to most drivers, there is nothing seriously wrong with it, when you need it, and it suffices greatly for when you need to avoid an obstacle or make steering corrections to your traejectory.

However, when we do encounter a corner, we see it and plan it, do we simply turn the wheel like this? Not nessecarily. If the steering input is relativelly small. I.E. a very slight curve, you simply move the wheel somewhat with both your hands, no need for any excerise of arm-acrobatics. But, when you turn the wheel to an amount of say 90 degrees -- when one of your hands reaches the topmost point of the wheel and your other reaches bottom, do you keep both hands turning like this?

Otherwise, what happens if, in exactly that corner, you slide your right hand (assuming it's a righthander) to the top of the wheel (12 O'Clock) and than pull it back down, untill the hand gets back to where it started in  (3 O'Clock, the right-end of the wheel). What happens than? You have the wheel turned to the same amount, but your hands are on both sides of the wheel: 9 and 3. So? Your hands are holding the wheel as if your were driving straight ahead, which allows you both to grip the wheel in a more vigilant and relaxed manner, but also be able to make little corrections easily or even make a large correction for a miscalculation, a tightening corner, a pit or stain of oil mid-corner, an obstacle, a skid, etc. And this amount of steering should suffice greatly.

Let's recap: You reach a righthander and you assume you need to turn the wheel one-quarter of a turn of lock, or 90 degrees. So you slide your right hand to the top of the wheel and pull back down to the right end of it, all while the wheel is sliding under the fingers of the left hand. You have turned the wheel 90 degrees and behold! your hands are again in the static posture, a magic! It can also be described like this: You see a corner, you assume you need to turn the wheel 90 degrees right, you move your right hand 90 degrees left so that when you pull back, your hand gets back to where it started.

What about tracking-out of the bend? Let the wheel straighten-up, maybe just turn it back by feel? No. We do the same thing we did going in, in reverse action. We relocated the right hand before the corner to the top of the wheel and pulled down. Now, we relocate the left hand to the top of the wheel and pull back down, and again, we find ourselves instantly at 9 and 3. With these two movements, going in and out, we kept the hands in 9 and 3 for a substantially larger time overall.

This might sound kind of complex, but in fact it becomes quite natural and simple once you get used to it. The main point here is to apply steering predictivelly. Instead of starting at 9 and 3 and than commencing the steering movements, so that in the corner your find yourself in an awkward hand position, you predict how much steering you need to turn, than you relocate your hands before the turn so that, we you turn, your hands return to 9 and 3. Than, you do the same going out, so that your hand movements mirror one another. Just like this:


You will quickely learn that wide-radius turns at intersections and junctions tend to require about this amount of steering rotation, but what happens if you need to turn the wheel more than that? Let's assume we are driving on the right (as opposed to places like the UK) and we need to turn right into a relativelly sharp corner in an urban area. This type of turn requires twice the amount of steering: a half-turn of lock (180 degrees). I have witnessed an interesting variation of this technique where you turn  the wheel just 90 degrees and than make the extra 90 with both hands, but I do not like this style. Here's the classic way of doing it: Pulling the wheel a full 180 degrees.

This might feel a bit odd at first, but it requires you to slide your hand (right hand in the case I stated above) and pull the wheel all the way across, and the left hand is just staying in place and letting the wheel slide under it's fingers with control. Like I said, this might feel a bit odd but it carries the great advantage of being able to perform a relativelly sharp turn with no more than one hand motion. A little tip of my own: When you cross the hand, hook the thumb under the spore of the wheel, just below the fingers of the other hand, so that you can pull a full 180 degrees.


But what if it gets tighter than that? Well, you will be surprised to learn it is no different. If the turn requires 90 degrees right you relocate the right hand 90 degrees left. If the turn requires 180 degrees left you relocate the left and 180 degrees right. If the turn requires 270 degrees left (3/4 of a turn of lock), you can actually relocate your (left) hand 270 degrees to the right, which means placing it on the bottom of the wheel. No, not with your palm, you actually grip the wheel with the hand upside-down (palm pointing up). This might feel really awkward but it becomes natural quickely, and enables you to turn an insanly large amount of steering in one "go", and than get back to 9 and 3, effective!

Remember though, that the opposite palm should always remain in position and let the rim slide under it with control. Also remember to mirror your hand movements: Turn-in by one hand that is relocated to pull the wheel as much as nessecary, and exit the turn by pulling back with the opposite hand -- and here's where a lot of  people go wrong.


The Steering Action
The steering action performed by turning the steering wheel, utilizes the steering mechanism to tilt the front wheels into a corner. Turning the front wheels gets them to roll towards the corner and direct the car into it. This discription is actually very simplistic. First, we must understand that the tire does not want to roll aside like this. The rubber wants to keep on going straight, and so does the whole car. The rubber in particular is elastic, which actually allows it to do that.

You turn the wheel, but the actuall patch of rubber on the road, twists aside in order to keep on going straight. Since rubber does not have an actuall will of it's own the actuall result is that the wheel is actually turning a bit less than the amount it is turned. This difference is measured in the angle between where the wheel is pointed and where the tire is actually going, and that's a "slip angle".

In fact, it becomes even more complex when talking about tire sidewall cramming, chassis twisting, rear-wheel slip angle, weight transfer and weight distribution, steering drag, body roll, longitudinal forces and speed, but what you need to know is that steering should be smooth and progressive but never slow. The more steering required, the faster it can be turned to result in a smooth output. "Sharp" steering movements might be required in times, but they are situations forced unto the driver due to the required driving line. They are not a desired input.

Other Techniques -- Extremities
Should we limit ourselves to one steering style, or should we use multiple techniques to serve different causes?  Is our very thought in terms of applying one method and/or the other is misintended? The short answer is yes and no. Yes, because no one technique can always work for all situations. No, because most "normal" situations can be negotiated very well by use of a one, uniform method.

It's not that there are no other techniques to learn, it's simply that the cases requiring their application should not be considered exceptional or, in the professional terminus technicus, an "extremity". With reference to steering styles, there are several extremities.

The first is where the car is old and has a heavy steering mechanism with no hydraulic support (i.e. no power-steering). In very low-speed manouvering, mainly parking, the steering tends to become very heavy. Here, we need to "shuffle" our hands, which carries some resembelence to the above technique: You relocate your one hand to the top of the wheel and pull down towards 7 O'Clock on the wheel, and than push up with the oppposite hand back towards 12O'Clock, reaching the required amount of steering rotation with such hand movements of about 120 degrees each. With practice, both hands mirror each other and it seems that the driver is "milking" the steering mechanism. This is only relevant to these types of cars in this particular situation.

The same situation (low-speed) parking, will in times be considered an extremity also in modern cars. When we are talking about a seriously slow steering manouver, or perhaps steering performed in a fully stop, we can let ourselves press the palm of the pulling hand against the wheel and turn it like this as much as we need. Still, we should keep our opposite hand in place to support the movement, and -- having turned the wheel to the required amount -- slide the hands to the right spots on the wheel. Rather than being another technique, this is simply a variation of the standard technique where you use the palm of the wheel and not the fingers.

Another extremity is when you turned the wheel with both hands to the point where your forearms became completly entangled and more steering cannot be applied, and you actually do not some extra extention of steering. For the sake of disscussion let's say you turned the wheel 270 degrees left with both hands to avoid an obstacle. Now, you need a bit more steering, but your hands are completly entangled, right hand on the bottom of the wheel (6 O'Clock), left hand ontop of it. So, you pull your right hand back and place it back ontop of the wheel, and than you open the right hand and press the palm against the wheel and turn the extra 90 degrees, and your hands return to 9 and 3 after turning a full 360 degrees.

A similar course of action is where you relocate the hand to pull the wheel to a certain quantity in one direction and, while pulling the wheel into the corner, you find it nessecary to turn the wheel away from the corner and all the way to the other direction. Say we relocate the right hand to the top of the wheel to pull 90 degrees right. Just as we start pulling, a car rolls into our direction, forcing us to steer sharply to the other direction. We push down with the hand that's doing the steering, under the stationary hand if required. It's range of motion is all the way down to the bottom of the wheel (6 O'Clock).

If it gets there and we actually need a bit more extention, we relocate our other hand to the top of the wheel and palm the wheel with our opposite palm and we have now returned to 9 and 3. To know how much we turned, we think about how much steering we initially wanted to apply. If I relocated my hand to pull 90 degrees right, pushed all the way down and than an extra 90 degrees, we do 360, minus the amount we wanted to turn, which is 90 degrees, which adds up to 270 degrees.

The last extremity is what I like to call "a situation where you need to turn as much steering as possible as quickely as possible". The normal steering technique normally suffices both for slow inputs and for large and quick inputs, but sometimes you need to turn the wheel an awfull a lot very very quickely (say, from lock to-lock), and this becomes more effective when a different style is adopted. Let's say I need to turn the wheel all the way right from lock to-lock. My hands are at 9 and 3. I push with the right hand all the way over (180 degrees) and than cross the other hand that pull the extra 180 degrees. A full 360, hands again in 9 and 3. Three sequences like this actually suffice in turning the wheel from one edge of the rack to the other!

Other Techniques -- Why not

The goal of this section is to specify the advantages of this technique over the others:

1. Range of Motion: This steering technique allows to turn the wheel 270 degrees in one hand motion, and a full 360 degrees by a more complex manouver, and than return to a hand position that allows to turn an extra 270 degrees, and further if nessecary. This also helps with turning the car, because you get a single hand movement, which is easier, smoother and yet decisive as nessecary. It is particularly effective during a set of successive corners.

2. Maintainence of the basic hand position for maximal amount of time: In this technique, you keep the hands in 9 and 3 for the maximal amount of time possible: Before the corner, in the corner, after the corner. In the timespawn in which the hands are not in 9 and 3, at least there is one hand in the right spot. This proves superior over the technique where both hands are relocated before the corner. In that technique, you have to perform the hand relocation ealier before the corner and place both hands in the wrong posture, just in order to have them in the right position somewhere within the corner, and unwind it and than finding yourself replacing the hands at track-out.

3. Maximal sensitivity: Pulling the wheel is done with greater sensitivity and ease than pushing, especially since the hand does not does not go below 9 or 3, and due to the extra sensory input of the opposite palm.

4. Symmetry:  One hand turns the wheel while the other is letting the wheel run under it, and than tracking-out by the opposite hand pulling back and the other in "supervision". This contributes to elegance, smoothness in turning-in and tracking-out and to the points mentioned above.

5. Sense of turning: With this technique, you are aware of how much you turned and where the wheels are pointing, making it easy to control the car on the limit.

6. Ability to steer one-handed: In rallying and road driving, this technique is friendly for one-handed steering, and hence allows to operate the gear lever and handbrake, and perform manouvers like double slides, handbrake turns and J-turns.

7. Two handed-steering: There are always two hands on the wheel and always at least one hand gripping and guiding the steering wheel.


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